Transformation in Wireless Connectivity: Guide to Prepare Airports (2023)

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7   C H A P T E R   1 1.1 Airport Uses of Wireless Technologies Understanding the applications that wireless technologies can unlock is part of the decision- making process for investments in wireless infrastructure. This chapter provides an overview of the current and potential uses of wireless technologies in an airport environment with respect to passenger experience, airport/airline operation, commercial services, safety and security, and travel health. In this guide, a wireless use case is a type of application that uses wireless access technology to provide value to the airport and its stakeholders. Some of the analyzed use cases are widely adopted (e.g., mobile communications for visitors and airport staff radio communications), although not necessarily leveraging all potential wireless technologies that support them. Others are common use cases in airports, but they use wireline communication infrastructure instead of wireless. Finally, some use cases are foreseen to be adopted in airports following trends in other industries. Table 2 outlines selected use cases under each category and their applicability to different types of airport facilities. These use cases were identified and selected in consultation with the ACRP Project 03-57 Airport Advisory Committee, which comprises all four categories of commercial service airports as well as general aviation airports. Appendix A details technical requirements and wireless technology enablers designated for each use case. 1.1.1 Passenger Experience and Commercial Services Figure 2 outlines the various activities and functions travelers experience at an airport before departure and after arrival that could be enhanced by wireless communications. Activities may include interactions of passengers with airport and airline infrastructure for transportation, checkpoint access, and travel processing, as well as on-site commercial services such as retail and food and beverages. In addition, access to information is essential for today’s passengers, both for journey updates and wayfinding and for entertainment and business tasks performed by passengers during dwell times at the airport. Wireless Parking and EV Charging Navigating to and finding available parking spots can be challenging, and the ensuing frustra- tion naturally leads to a negative passenger experience. Parking occupancy systems, consisting of wireless sensors indicating available parking spots, can alleviate frustration and improve the passenger experience. The data from these wireless sensors are transmitted into a central pro- cessing unit that then commands electric signs and lights at parking sites to guide drivers to available parking spots. Taxonomy of Wireless Technologies and Their Uses in Airports

8 Transformation in Wireless Connectivity: Guide to Prepare Airports Autonomous vehicles and robotics Autonomous surface vehicles ● ● ○ ○ ○ Mobile robots ○ ○ ○ ○ ○ Uncrewed aerial vehicles (UAVs) ○ ○ ○ ● ● Incident response and recovery Radio communications for first response teams ● ● ● ○ ○ First responder personal protection ● ● ● ○ ○ Wireless real-time surveillance for incident investigation ● ● ● ○ ○ Wireless use case Airport type Primary Non-primary Other Large hub/ medium hub Small hub/ non-hub General aviation/ reliever Cargo MRO Passenger experience and commercial service Wireless parking and electric vehicle charging ● ● ● Wireless HD screens and information kiosks ○ ○ Wireless self-service check-in kiosks ● ● Mobile passenger checkpoint ● ● ○ Contactless purchasing ● ○ ○ Mobile communications for visitors ● ● ● Enhanced in-building mobile carrier coverage ● ○ Location-based visitor information ● ● Mobile AR wayfinding ● ○ Airport/airline operations Wireless enterprise communications ● ● ● ○ ○ Wireless-based passenger flow monitoring ● ○ Wireless asset tracking, monitoring, and control ● ○ ○ ● ● Wireless advanced visual docking guidance system (A- VDGS) ○ Wireless cargo asset tracking ● Airport staff radio communications ● ● ○ ○ ○ Wireless baggage tracking ● ● Wireless taxiing guidance ● ○ ○ ○ Connectivity of electronic flight bag (EFB) and other aircrew devices ● ● ○ ○ Mobile AR for aircraft maintenance ○ ○ ○ ● Safety, security, and surveillance Wireless airfield sensors ● ● ● ● Wireless-based automated access control ● ● ● ● ● Wireless closed-circuit TV surveillance ○ ○ ○ ○ ○ Wireless-based airfield vehicle and aircraft surveillance ● ○ ○ ○ Wireless virtual ramp/ground traffic control system (VRCS) ○ ○ ○ Terminal environment sensing ● ● ○ Mobile AR surveillance ○ ○ ○ Table 2. Summary of use cases and applicability to airport facility types.

Taxonomy of Wireless Technologies and Their Uses in Airports 9   Travel health Wireless-based social distancing monitoring ● ○ ○ Wireless-based automatic passenger temperature screening ○ ○ ○ Touchless travel ● ● ○ Wireless-based staff contact tracing ○ ○ ○ ○ ○ Note: ● Applicable ○ Potentially applicable Abbreviations: AR = augmented reality; HD = high definition; MRO = maintenance, repair, and overhaul. Wireless use case Airport type Primary Non-primary Other Large hub/ medium hub Small hub/ non-hub General aviation/ reliever Cargo MRO Table 2. (Continued). Figure 2. Passenger experience and commercial service use cases.

10 Transformation in Wireless Connectivity: Guide to Prepare Airports With the number of electric vehicles (EVs) continuing to grow, more airports are installing EV chargers. These charging stations must connect to a network to process payments and relay information about the EV charging status, which can then be accessed through mobile devices. The range and availability of wireless internet signals or cellular services are identified in ACRP Synthesis 54: Electric Vehicle Charging Stations at Airport Parking Facilities as a significant con- sideration for the location of installation of the EV chargers (Richard 2014). This use case requires a wireless technology that covers relatively long distances and a large volume of stationary devices installed throughout the parking facilities, with minimum throughput. Cellular or unlicensed LPWAN or a mesh personal area network (PAN) would be a good candidate for such an application. Value Proposition: • Customer satisfaction. Smart parking and EV charging stations providing charging status, enabled by wireless sensor networks, improve customer experience and loyalty to the airport brand. Monitoring information on available parking spots and charging status can be made available through an airport mobile app, fostering new levels of engagement with travelers. Parking occupancy systems indicating available parking spaces increase certainty and effi- ciency for the passenger journey, reduce traveler stress, and enhance customer satisfaction. • Nonaeronautical revenue. Certainty about the availability of parking spots maximizes park- ing occupancy and revenue generated by parking facilities. In addition, integrating EV charg- ing stations in parking facilities will attract the EV user segment of the market to the airport. Although mostly offered as a free service, EV charging stations are used by some small airports as a magnet for customers who come to the airport to charge their vehicles and, while the vehi- cles charge, spend time at airport concessions. Wireless High-Definition (HD) Screens and Information Kiosks Smart screens and information kiosks are emerging as effective methods of providing timely assistance to travelers, especially when airport staff are unavailable. Smart screens and kiosks dis- play dynamic and real-time content about airport services, flight information, and advertising. Interactive information kiosks have smart search capabilities and mobile wayfinding integration and can remotely control information on touch screens using the content management system. Wireless smart screens and kiosks are connected to an airport’s intranet to retrieve real-time information, with multiple devices in the network being updated at the same time. Traditional information screens and kiosks are isolated (with preloaded media content) or connected to an airport’s wireline infrastructure, which may not be able to meet the volume of or be flexible enough for the dynamic and real-time information required by today’s travelers. High-capacity technologies such as cellular and Wi-Fi are better suited to provide timely assistance to travelers. Wireless technologies can now provide Mbps data throughput indoors at a latency of less than one minute, which should be sufficient to allay any concerns about the feasibility of transmitting real-time content over wireless networks. Value Proposition: • Customer satisfaction. Wireless HD screens and information kiosks save travelers time and alleviate stress caused by searching or waiting for assistance from airport personnel. They allow travelers to explore information about the airports and flights at their convenience, can incorporate tools for planning trips and mitigating travel disruptions, and can interact with passenger devices for better control of the trip by the traveler. • Nonaeronautical revenue. HD screens can generate advertising revenues and can also help increase terminal concession sales. Advertising revenues could come from in-terminal tenants

Taxonomy of Wireless Technologies and Their Uses in Airports 11   or other businesses placing advertisements on HD screens. Such advertising would likely stimulate additional sales for in-terminal tenants (e.g., retailers, food and beverages), which in turn would increase airports’ revenues. Flexibility in deployment enabled by wireless technologies can help airports optimize the location to maximize traveler attention span or customize content. • Reliability of operations. Wireless information screens and kiosks are flexible and portable. Therefore, they can be relocated easily and inexpensively to meet the needs of changing pas- senger flows in the terminal. Maintaining user-friendly information tools at optimal loca- tions will help enhance the overall predictability of airport operations, as travelers will reach their desired destinations on time. Wireless notifications using visual signage on screens pro- vide airports with redundancy and backup capabilities in the event the main infrastructure becomes unavailable. Accordingly, ACRP Research Report 170: Guidebook for Preparing Public Notification Programs at Airports recommends the use of wireless notification systems for public information in emergencies (de Rodriguez et al. 2017). • Efficiency and sustainability. Wireless HD screens and information kiosks reduce the costs of cabling infrastructure and the carbon footprint of construction and can enhance the volume and location of information points for travelers. This, in turn, reduces the number of airport personnel needed to assist travelers and increases operational efficiency. Wireless Self-Service Check-In Kiosks Self-service kiosks expedite passenger processes in airports by allowing travelers to check in, tag, and drop off their checked baggage themselves. Both self-service kiosks and bag-drop kiosks can incorporate biometric integration that enables fast and secure passenger identification. Radio- frequency identification (RFID) technology has been used to read passports and baggage tags. Wi-Fi or Bluetooth-enabled kiosks can support remote control by smartphone for a touchless experience. Traditionally, passenger-processing stations, including self-service kiosks, have been owned and operated by airlines connected to wireline networks which, in many cases, are independent of each airline. With the advent of Common Use Passenger-Processing Systems, counters and kiosks supporting multiple airline processing functions are increasingly available at airport ter- minals. More recently, cloud-hosted passenger servicing platforms provide airport facilities with airline applications via common service interfaces. Wireless connectivity enables service integration with “accessible anywhere” kiosks, which allows flexible deployment of fixed or mobile counters and kiosks. Mobile counters and kiosks are especially useful in situations where it is advisable to relocate the passenger-processing services within the terminal or offsite (such as hotels or rail stations) to comply with distance require- ments dictated by travel health regulations. Mobile kiosks can be enabled by Wi-Fi or cellular if they are relocated outside the airport. ACRP Report 136: Implementing Integrated Self-Service at Airports states that wireless connectivity for passengers and kiosks is necessary to advance airport self-service to the next stage, where physical assets are separated from the processing functions, allowing flexible, nonlinear passenger processes and new locations for these func- tions, including offsite (Barich, Inc. 2015). Value Proposition: • Customer satisfaction. Self-service kiosks enable travelers to check in quickly, preventing the potentially long wait times for service by an airline agent. This reduces traveler stress, and faster processing allows the traveler more time to reach their gate of departure. A faster check- in process will improve the traveler’s satisfaction with the operations at the airport. Wireless kiosks are more rapidly deployed or removed according to demand, at the appropriate loca- tions, to optimize their location for travelers.

12 Transformation in Wireless Connectivity: Guide to Prepare Airports • Aeronautical revenue. Wireless self-service kiosks can be an airport-owned asset for common airline use. This resource can provide added value to airlines as a service available anytime/ anywhere or deployed on demand. • Reliability of operations. The predictability of operations and passenger flow will be enhanced by the integration of wireless self-service kiosks. The average check-in time can be monitored and analyzed to determine the overall processing time of a passenger from check-in to security screening. The enhanced predictability of operations allows airports to achieve better utiliza- tion of the kiosks. Mobile Passenger Checkpoint Biometrics is an automated identity verification system, which uses facial recognition and finger- prints to verify travelers’ identities swiftly, accurately, and efficiently. An increasing number of airports, including Boston Logan International (BOS) and Orlando International (MCO), are rolling out full-scale biometric services for all identity checkpoints in the travelers’ journey pro- cess. Airlines are also gradually adopting biometric solutions to expedite their boarding process using the cloud-based Customs and Border Protection (CBP) identification database. For example, American Airlines has deployed biometric boarding at its largest hub, Dallas Fort Worth Inter- national (DFW). The Transportation Security Administration (TSA) is gradually integrating the portable Creden- tial Authentication Technology (CAT) system in airports across the country as a component of their checkpoint screening process. CAT enables TSA officers to verify a traveler’s identity and flight details and status in real time. Although deployed as fixed biometrics stations, wireless-enabled biometrics technology would allow airports to set up mobile and flexible passenger-processing stations to optimize the allocation of the available workforce to focus on travelers who need further assistance with their processing. Wireless biometric passenger identification can be applied to self-service kiosks, TSA screening stations, CBP for international traveler and immigration processing, and gate boarding. For example, CBP uses wireless biometrics devices for exit processes at Boston Logan International (BOS). Value Proposition: • Customer satisfaction. Identity verification at checkpoints takes a significant amount of time to process which leads to long waits for travelers. Using portable and mobile traveler verifica- tion checkpoints can expand and optimize the location for automated identity verification. A shorter wait time would increase traveler satisfaction. • Aeronautical revenue. Airlines are gradually adopting biometric solutions to expedite their boarding process using the cloud-based CBP identification database. Mobile passenger checkpoints can be an airport-owned asset for joint or common use by airlines. This resource can provide added value to airlines as a service available anytime/anywhere or deployed on demand. This value proposition can generate new aeronautical revenue streams in the form of service infrastructure for airlines. • Reliability of operations. Expedited traveler processing and boarding improve the predict- ability of traveler movement and reduce travelers’ journey time in the airport. Mobile check- point identification supports the quick deployment of checkpoint resources at any step of the passenger process. It can expand processing resources during high-demand peaks, thus enhancing the reliability of operations. • Efficiency and sustainability. The introduction of mobile passenger checkpoints reduces the costs of cabling infrastructure and the carbon footprint of construction and replaces the need to manually check paper travel documents by providing an automated identity verification

Taxonomy of Wireless Technologies and Their Uses in Airports 13   process everywhere across the stage in travelers’ movement through an airport. This, in turn, reduces the number of required airport personnel to assist travelers and increases labor oper- ational efficiency. Contactless Purchasing Airport concessions (e.g., retail stores, foods and beverages, car rental, and car parking) that traditionally rely on staff to process orders and payments from customers are now adopt- ing contactless methods like self-service kiosks or payment stations, as well as mobile apps and websites customized for mobile devices. Customers now can use self-check-out at pay- ment kiosks by scanning their products and swiping their credit or debit cards to complete the transaction. “Just walk out” technology takes this process a step further, by having the customer swipe their card first, pick up the items they wish to purchase, and simply walk out of the store eliminating the need to stand in line even for self-checkout. This technology is enabled using cameras and RFID sensors to detect which items customers take with them and automatically charge the card when they exit the store. Newark Liberty International Airport (EWR) has deployed this approach at several stores, and LaGuardia Airport (LGA) will soon follow. Hudson, a major air- port store chain, has reached an agreement to use Amazon Go technology in selected Hudson travel convenience stores. The first Hudson Nonstop cashierless store opened in March 2021 at Dallas Love Field. Although earlier payment ordering kiosks have traditionally been wireline stations, it is becom- ing more cost-effective to deploy and maintain them if they are running on portable devices such as tablets. Ordering applications on smartphone apps enable full contactless alternatives, includ- ing stores offering delivery throughout the terminal, where location-based services provided by mobile devices can help staff locate their customers throughout the terminal for faster delivery. For example, @AtYOURGate, an in-airport order and delivery service, is available at 17 U.S. airports as of October 2021. Passengers can access the services via websites, mobile devices, QR codes, and kiosks, and the deliveries are carried out by robots at selected airports. Mobile-based purchasing is complemented by the ability to share proximity-based marketing messages for passengers in the vicinity of a concession. Sensing for visitor tracking and charging is also best served by wireless IoT components. Value Proposition: • Customer satisfaction. With contactless payment solutions such as “just walk out,” customers will not have to wait in line to be checked out. In-airport on-demand delivery services pro- vide valued convenience and improve the overall airport experience for passengers, thus will increase customer satisfaction. • Nonaeronautical revenue. With shortened wait times during checkout, customers will be more likely to spend time in concessions. In addition, automated purchasing processes increase the capacity of concessions to serve customers, enabling the generation of higher sales volumes. In-airport delivery services that allow passengers to order food, drinks, or merchandise (e.g., toothpaste, books, and neck pillows) from anywhere in the airport and have them delivered to their departure gate are most likely to stimulate sales. • Efficiency and sustainability. Contactless payment solutions decrease the need to employ cashiers for concession stores. It also speeds up the checkout process, as customers will not have to wait for staff to manually operate cash registers, allowing travelers to reach their gates sooner. Additionally, with less staff required for concession stores, screening and badging needs would also decrease, thereby decreasing the paperwork and liabilities of non-airport operations-related workers employed at concessions.

14 Transformation in Wireless Connectivity: Guide to Prepare Airports Mobile Communications for Visitors Mobile devices have become an essential part of people’s lives, making the devices used by passengers and visitors a major consumer of wireless connectivity. These include cellular/Wi-Fi/ Bluetooth-enabled phones, tablets, computers, smart watches, smart glasses, and any other electronic device that visitors and passengers carry with them and use to stay connected for entertainment and business tasks. Specific mobile applications provided by airport authorities, airlines, or travel companies are also used by passengers for checking in before a flight, checking their flight status, tracking their luggage, obtaining weather updates, or finding out all the neces- sary information about their flight status or how to get around the airport. Airport visitors consume internet traffic at varying levels, depending on passenger volume and traffic distribution throughout the terminal, resulting in high and low traffic density areas. Appli- cations can also vary from light web surfing to heavy multimedia content streaming. In addition, a growing number of mobile applications use location tracking and unlocking location-based services (see corresponding use cases). Because visitor communications are traffic-demanding but not a critical service for airport operations, the de facto technology option to complement public cellular coverage is Wi-Fi, which offers high capacity but no guaranteed reliability of service. However, distributed antenna systems (DAS) infrastructure is now positioned as a complement to enhance public cellular coverage, using mobile carrier infrastructure, inside the terminal (see next use case). It is valu- able to allow multiple channels because high-speed wireless connectivity is expected by airport passengers nowadays. Value Proposition: • Customer satisfaction. Most of today’s travelers pass through airports carrying a smart- phone, laptop, or tablet, and expect wireless connectivity at the airport. They will most likely not be satisfied with their airport experience if good wireless connectivity is not available, par- ticularly those who are connecting with a long layover. Providing good wireless connectivity to travelers is essential for travelers’ positive experience at airports. • Nonaeronautical revenue. Access to updated information about flight status reduces traveler anxiety and uncertainty and helps travelers to relax, which may lead to more spending at air- port concessions (OAG 2019). A connected passenger will be satisfied and certain about their travel plans and will thus generate more revenue. In addition, geofence marketing can generate additional revenue from concessional tenants (see Location-based visitor information, below). Enhanced In-Building Mobile Carrier Coverage Emerging architectures and business models for wireless technologies are enabling venue managers to provide infrastructure capacity to mobile carriers. Using either DAS or network configurations based on the roaming federation Wi-Fi service OpenRoaming, mobile carrier subscribers can continue enjoying fast cellular service inside buildings, guaranteed by service level agreements (SLAs) between the mobile carrier and the in-building network provider. This new situation provides a similar mobile communications service as in the previous use case, but with a crucial difference: The visitor does not need to actively select the best access technology for their application; instead, this is performed automatically by the network. Thus, login and user management processes are transparent or nonexistent when entering an airport terminal, and as a result, the user does not need to search for signal coverage or log in through user portals. On the venue manager side, the airport network provider effectively manages the mobile carrier and is required to provide the same level of service, thus requiring high-capacity wireless technology (4G/5G DAS or Wi-Fi 6/6E).

Taxonomy of Wireless Technologies and Their Uses in Airports 15   Value Proposition: • Customer satisfaction. In-terminal mobile carrier coverage enables transparent, automatic selection of the network provider that best covers the user. This seamless wireless provision guarantees the best possible service and minimizes outages, minimizing dissatisfaction with the service quality. • Nonaeronautical revenue. Participating mobile carriers pay the venue manager to put their subscribers on the building wireless access network, using pre-negotiated prices or per traffic unit. This creates a revenue stream to which airports did not have access before. Depending on the agreement with the mobile carriers, revenue may vary based on foot traffic and net- work quality. Location-Based Visitor Information Information for a passenger or visitor over an airport application can be tailored depending on their current location, improving wayfinding information and creating marketing opportu- nities based on retail advertisement. The additional infrastructure required for this service is usually very cost-effective and requires little additional capacity in the network. Proximity marketing, using beacon technology, is enhancing passenger experience at airports by sending personalized messages to users’ smartphones about retail promotions and other information. These messages are tailored according to the location of the traveler in the termi- nal. BLE beacons also enable expedited access to fast-track security by allowing passengers to automatically use their frequent flier cards. Location-based visitor information enables a per- sonalized traveler experience and enhances the revenue generated from non-airline revenue streams. The Airport Delight Report (OAG 2019) identified in-airport turn-by-turn directions for navigating terminals and gates as the main advancement in efficiency and customer experi- ence. Miami International Airport (MIA), like many others, has also deployed a beacon-enabled application that is aware of its surroundings and tailors the traveler’s experience based on their real-time location at the terminal. Location-based services that identify the indoor passenger location in facilities provide an opportunity to improve the tracking of social media postings and correlate them to emergency events. ACRP Research Report 170 describes the use of geographically targeted, text-like wireless emergency alerts for mobile users (de Rodriguez et al. 2017). Value Proposition: • Customer satisfaction. Retail advertisements with high-value deals will give travelers a more informed and positive shopping experience while going through concessions. The visibility of shopping and entertainment options in the airport affects positively the customer experience of the airport. • Nonaeronautical revenue. Proximity marketing can generate revenue from the concessional tenants. If commercial tenants wish to offer advertisement pop-ups on travelers’ devices to attract more customers, this increased revenue generation for the tenant translates into increased revenue for the airport through fee or revenue-sharing formulas. This would pro- vide an additional stream of nonaeronautical revenue for airports. • Reliability of operations. Guest mobile communications also enhance effective responses in cooperation with airport visitors. ACRP Synthesis 82: Uses of Social Media to Inform Opera- tional Response and Recovery During an Airport Emergency introduces use cases for the use of social media to enhance response to emergency events at the airport (Smith and Kenville 2017). Most social media activity occurs using visitor mobile phones, which in turn have global positioning system (GPS)-enabled geolocation tags in the mobile application. Location-based

16 Transformation in Wireless Connectivity: Guide to Prepare Airports services, can improve the tracking of social media postings and correlate them to emergency events. Mobile Augmented Reality Wayfinding Augmented reality (AR) applications running on smartphones expand the quality of informa- tion accessible by passengers. In an AR application, the device camera shares its current image with a software service, generally running on the cloud. The service processes the image and returns contextual data in the form of textual or graphical information superposed on the camera image to increase awareness about the signage and surroundings, enhancing airport wayfinding. AR is often integrated with location-based services to use the device’s location to produce con- textual information. Some AR technology allows the images to be viewed in 3-D, thereby taking wayfinding to a higher level of use and ease for travelers. Typical applications of AR are language translation and directions to the gate. Location-based AR applications have debuted at San Jose International Airport, where users can use the AR app for wayfinding. Users can view AR digital billboards that show arrival and departure information. Value Proposition: • Customer satisfaction. Mobile AR wayfinding enhances customer experience as tailored information improves travel certainty and peace of mind. In addition, the perception of ser- vice personalization is greatly appreciated in the customer experience. AR can also improve information about commercial offerings at the airport and promote concessional sales and consumer experience. • Reliability of operations. Providing travelers with aids such as mobile AR wayfinding helps travelers to find their gates or other facilities easily and quickly. This use case also enhances the predictability of traveler movement as it ensures they reach their desired destinations in the airport as quickly as possible with as few delays as possible. 1.1.2 Airport/Airline Operations To conduct their businesses and operations, airport and airline staff rely on a diverse set of technologies to communicate with each other as well as with devices, machines, and assets. Auto- mated systems also require communication, sometimes with no human intervention. This category includes the use of wireless technologies supporting the aeronautical opera- tional flows not related to a passenger; namely, aircraft and cargo operations. These activities require coordination of tasks performed by airport and tenant staff, such as airlines and fixed- base operators (FBOs) providing aeronautical support, for continuity of flight operations with- out disruption. Figure 3 outlines the scope of airport operational functions that occur during the landing, turnaround, and departure of an aircraft. Wireless Enterprise Communications Enterprise applications comprise communication software established to support business processes. In the airport environment, several enterprise networks are running separately for airport operations and tenants, although they may share some connectivity infrastructure. These networks enable airport and tenant staff to exchange information, control devices, collaborate, and use operating systems exclusively available to authorized users. An enterprise network is composed of secure application servers providing authorized users with the data and services they need to run the business. Typical technologies to support wireless enterprise communica- tions are cellular, Wi-Fi, and AeroMACS.

Taxonomy of Wireless Technologies and Their Uses in Airports 17   Examples of enterprise applications at the airport include communications for administrative tasks such as intranet and file sharing, human resource management, conferencing, or email. Applications for airport operation tasks include passenger-processing systems, departure con- trol systems, and GIS map sharing, in addition to applications for staff communication in the field. For staff communication in the field, FBO staff are equipped with mobile devices to per- form ground support during a turnaround at the apron and “follow-me” vehicles with updated runway activity and estimated flight traffic for safer and more efficient surface movement. For non-primary and general aviation airports, mobile snow desks are a cost-effective solution to monitor the airfield and submit NOTAM notifications during winter weather events, obviating the need for centralized snow desks. Enterprise airport applications can be hosted on business premises but, due to their manage- ment complexity and the lack of technical resources, they are increasingly being hosted in the cloud. This trend started with passenger-processing services but is expanding to airport opera- tions in general. This new paradigm brings opportunities for enterprises to reduce costs and increase the resiliency of their enterprise networks, assuming stable WAN/internet connectivity is maintained. The core network and WAN backbone access usually rely on wireline infrastruc- ture, but wireless communication to the end user increases the mobility and convenience of business staff, such as security and airfield personnel performing duties on the field. Figure 3. Airport/airline operations use cases.

18 Transformation in Wireless Connectivity: Guide to Prepare Airports Value Proposition: • Customer satisfaction. Wireless enterprise communications address the network needs of airport tenants. Providing reliable, secure network services to the tenants for their specific applications serves their business needs and therefore increases customer satisfaction. • Reliability of operations. Enterprise applications integrate with complementary tools and platforms to improve collaboration among stakeholders. These tools support the processes necessary for collaborative decision-making (CDM) in the airport, consistent with the guide- lines developed in ACRP Report 137: Guidebook for Advancing Collaborative Decision Making (CDM) at Airports and expanded by ACRP Research Report 229: Airport Collaborative Deci- sion Making (ACDM) to Manage Adverse Conditions (Vail et al. 2015; Le Bris et al. 2021). CDM improves the planning and management of surface traffic management for day-to-day operations and in adverse conditions, reducing delays in both the movement and non-movement areas and enhancing safety, efficiency, and situational awareness. • Efficiency and sustainability. Wireless communications for enterprise applications allows airport and tenants to decrease the marginal costs of connecting new users to the network. In addition, wireless coverage supports mobility in the terminal and airfield, allowing the execu- tion of operational tasks on the field while minimizing displacements. Wireless-Based Passenger Flow Monitoring Real-time tracking of the location and movement of passengers generates actionable infor- mation about crowds and bottlenecks. By means of post-processing large volumes of historical tracking data, statistics and heatmaps can be generated about the usage of a terminal. A com- bination of tracking information with flight, retail, and even local weather data creates a wealth of information regarding how passengers use the airport under diverse circumstances. As an example, with this technology, it could be revealed that at a certain moment of the day a particu- lar area of the terminal is underused while another is overstressed with passengers and that such situations are caused by a series of daily flights accommodated in a certain area of the terminal. Multiple technologies enable passenger flow monitoring such as video cameras equipped with AI, stereoscopic cameras, infrared sensors, or light detection and ranging (lidar, which may be wireline or wireless). However, smartphone signal tracking by the wireless network (cellular, Wi-Fi, and/or BLE beacons) is a cost-effective approach requiring less sophisticated infrastruc- ture. Often, a combination of different technologies is chosen to maximize the accuracy and coverage of crowd movement. Tracking technology captures anonymous location information; however, airport mobile apps allow volunteer users to opt for location-based services and record personalized passenger tracking aspects such as the path to the gate or consumer behaviors. The Port Authority of New York and New Jersey (PANYNJ) has been using smartphone tracking technology since 2019 throughout its airports. Schiphol Airport, Auckland, Dublin, and many others are also implementing it. Value Proposition: • Nonaeronautical revenue. Historical data on passenger movements in commercial areas of the terminal give valuable information on consumer behavior. This information can in turn be used to drive data-based optimization of commercial activity, such as value-based loca- tion pricing for concessions, or estimate the conversion rates at different locations and times of the day. These tools improve consumer activity and generate higher ancillary revenue for tenants and the airport. • Reliability of operations. This use case can help airport security managers identify potential security or travel health risks due to the formation of crowds. In addition, passenger flow monitoring can be used to measure waiting times and transit times in real time and inform passengers of the status of security or taxi queues, or estimated time to the gate.

Taxonomy of Wireless Technologies and Their Uses in Airports 19   • Efficiency and sustainability. Understanding the way passengers use the terminals can help managers locate concession stores more effectively, identify operational inefficiencies through bottlenecks, reassign gates to better distribute passengers within the terminal, or redesign the building to improve the overall passenger experience. Using the existing wireless network infrastructure, which is normally used for providing internet access to visitors, to track smart- phone signals is an efficient way to perform passenger flow monitoring anonymously. Wireless Asset Tracking, Monitoring, and Control When embedded with electronic sensors and connectivity, assets can receive and transmit information about their status, empowering airport authorities to monitor, control, and track them. The monitoring, control, and tracking data usually converge at a centralized system known as Supervisory Control and Data Acquisition (SCADA). Data flow from the assets to the central- ized system and back through point-to-point communications or, more commonly, through an enterprise network. Wireless technologies expand these capabilities to assets that can be easily deployed, are located remotely, or are mobile. Advancements and price reductions in portable electronics are enabling wireless connectivity on devices not originally designed to relay their data or be con- trolled remotely, further expanding the scope of assets that can be controlled or tracked. Large- scale volumes of battery-powered, connected assets able to send status and position reports, or to be controlled remotely, enable the IoT for smart buildings and operations, and require the scalability and flexibility provided by low-power wireless communications. Airport personnel and physical devices are both mobile assets that can be tracked in an airport. Physical devices that can be tracked at an airport include airport and ground operations vehicles, passenger boarding gates, belt loaders for loading and unloading baggage, baggage-handling system and vehicles, gate display systems, system-wide closed-circuit television (CCTV) systems, passenger coaches, and refueling trucks. With personnel tracking, an airport manager will be able to assign and track the location of their workforce. Theft prevention is another common use. Airlines also track their cabin inventory (oxygen generators, life vests, portable oxygen bottles, first-aid kits) and aircraft parts using RFID tags. This solution allows them to perform leaner warehouse management and reduce the probability of lost items. Remotely monitoring assets allows airport managers to increase their awareness of the usage of their resources, and better plan for the utilization and procurement of resources. IoT can be used to monitor airfield assets, for example, airside asphalt conditions, airport terminal build- ings, passenger information and communication systems, safety, security systems, baggage- handling system, and intra-airport transportation systems. Value Proposition: • Reliability of operations. The most common applications for wireless asset monitoring include preventive maintenance by anticipating any malfunctioning and increasing efficiency by using data to better use the assets. Understanding the exact real-time location and health status of assets can help airport managers respond more quickly to unexpected situations where these assets are needed. • Efficiency and sustainability. Airports can leverage the power of wireless IoT to remotely control assets. Devices such as escalators; lighting systems; heating, ventilation, and air con- ditioning (HVAC); passenger bridges; or baggage-handling equipment were all originally designed to be manually controlled directly by a person. Wireless IoT has enabled these and other assets to be controlled remotely from a control room saving time and resources. Auto- matically logging the use-hours and the paths traveled can help identify and optimize move- ment patterns.

20 Transformation in Wireless Connectivity: Guide to Prepare Airports Wireless Advanced Visual Docking Guidance System (A-VDGS) When an aircraft proceeds into its parking position, A-VDGS allows aircraft to dock and park within the apron using enhanced visual guides and alerts for pilots, which improves safety as well as accuracy. The system sends real-time visual guidance to the pilot such as distance and azimuth and triggers an alert when an obstruction is detected on the apron, thereby averting any potential collision or incident. A-VDGS automates the docking process at the gate, which otherwise is a highly labor-intensive procedure and prone to costly human errors. Dallas Fort Worth International Airport (DFW) has been operating A-VDGS to ensure safe and efficient automated aircraft docking during regular and irregular operations. Value Proposition: • Reliability of operations. Wireless A-VDGS incorporates new surveillance technology including sensors and visual display facilities to maximize situational awareness and forecast- ing accurate turns. Wireless networks allow the deployment of these devices in the best loca- tions without being limited by IT and building infrastructure, thus improving the accuracy and visibility of guidance information. • Efficiency and sustainability. Airports consulted as part of this project make general use of wireline connectivity to support this use case and expressed concern that real-time infor- mation is better to be transmitted through wireline infrastructure. However, providing this application via reliable wireless communications (cellular or AeroMACS) has advantages in terms of flexibility of deployment, maintenance, and coverage of remote areas like parking spaces outside the apron, where it is not viable to install a wireline infrastructure. Wireless Cargo Asset Tracking Cargo tracking has become a key component for the logistics and supply chain industry. Cargo tracking reduces expenses in theft, loss, or any other form of mismanagement. It also saves time finding lost packages and increases customer satisfaction by keeping them always updated about the location of their package. Although cargo is the responsibility of airlines and handling com- panies, airports providing cargo asset tracking systems to their tenants can incentivize higher quality and efficiency in this operation and attract cargo business. Unit load devices (ULDs) equipped with RFID and other wireless sensors like Bluetooth allow for real-time tracking and traceability, optimizing load usage within supply chains and helping reduce the impact of accidental inventory mishandling. Monitoring the location and status of cargo is especially relevant in major cargo hubs where storage facilities are vast and complex. In these airports, multiple stakeholders are involved in the handling and processing of cargo items, not only within the airport facilities but also in logistics or business centers in the vicinity. Temperature-sensitive products, such as pharmaceutical and perishable products, rely on tracking systems to ensure their internal refrigeration systems are maintaining the cargo at the temperatures required by its content and that the items are not erroneously moved to locations where their integrity could be compromised. MIA, being a global cargo hub, is working to adapt its infrastructure to deal with the upcoming rise in pharma and vaccine transportation. South- west Airlines Cargo uses RFID tags for shippers on its aircraft, which allow verification of the temperature of sensitive goods without the need to open the cargo container. Value Proposition: • Customer satisfaction. Cargo servicing tenants operating in storage and handling facilities benefit greatly from traceability, tracking and environment monitoring features enabled by

Taxonomy of Wireless Technologies and Their Uses in Airports 21   wireless sensor networks, which ensures accountability and quality of the cargo involved. The advantages of operating a modern cargo monitoring network in large cargo hubs are evident because information can be more easily captured and shared for items that require the par- ticipation of multiple stakeholders in their storage, processing, and shipping. • Aeronautical revenue. More efficient cargo handling and shipping increase the capacity of the airport, which translates into higher revenue to airlines from cargo operations, which translates into higher land lease revenue for the airport. Airlines that provide cargo services become airport customers using cargo monitoring systems, environmental sensors, and wire- less networks used to enable these services, increasing aeronautical revenue. • Reliability of operations. Tracking systems, which ensure the correct storage conditions for sensitive cargo, help ensure time reliability and the quality of delivery of the product. Wireless sensor networks are increasingly supported by blockchain to record transactions occurring in monitored items, thus enabling accounting and traceability of cargo when in storage, offload- ing, and loading to an aircraft or vehicle. • Efficiency and sustainability. An instantaneous location of mishandled ULDs improves efficiency by eliminating the time-consuming manual search for misplaced items. Further- more, the same technology used for ULD tracking can be used for constant monitoring of environmental conditions such as temperature and moisture, which could impact perishable assets, thus monitoring all aspects of logistics using the same technology. Airport Staff Radio Communications Airport personnel often use radio communication devices for point-to-point communication regarding time-sensitive coordination or notifications using voice or short messages. This includes airport operations, security, and emergency work anywhere in the terminal or the airfield. The same equipment can also be tuned to monitor ATC communications or incoming/outgoing traffic communications at non-towered airports. Portable radios in consoles at command centers, carried by personnel, or mounted on vehicles enable either one-to-one or one-to-many voice communications in a rapid and reliable method. The use of these professional radio devices requires initial and recurrent training. Radio communications for airport staff are very light and make efficient use of resources, but they require very high levels of reliability and security. Because of this, they usually make use of private land mobile radio (LMR) systems, although AeroMACS and cellular networks can also support this capability. Value Proposition: • Reliability of operations. Radio communications for airport staff make use of dedicated channels which can be authorized to use for commercial purposes, privately licensed to the airport, or shared with public-safety authorities for “mutual aid” coordination. Owing to the robustness of the wireless channel and the devices, the probability of communication failure is extremely low. In the event of an incident, radio communication allows personnel to con- nect with their colleagues at a moment’s notice for timely coordination of airport operations, without the fear of suffering a break in communications. • Efficiency and sustainability. Radio communication systems for airport staff ensure efficient and quick relay of time-critical communications. This is a resource-efficient system to ensure the basic exchange of information that guarantees the continuation of operations. Wireless Baggage Tracking Implemented in 2018, International Air Transport Association (IATA) Resolution 753 man- dates airlines to track baggage at multiple key points in the journey. Although several IoT

22 Transformation in Wireless Connectivity: Guide to Prepare Airports technologies could support this application, IATA recommends the use of RFID technology at airports due to its accuracy, simplicity, and low cost. RFID has a major advantage over barcode scanning: It can track tagged items with more accuracy and from a longer distance. In addition, RFID can contain more information than a barcode. Baggage-handling systems can leverage RFID scanners throughout the conveyor belt system that takes bags from the baggage drop areas into the hands of baggage handlers located airside. These scanners can be fixed RFID readers or portable devices carried by airline personnel. The use of handheld baggage screening devices, especially, would benefit from having wireless con- nectivity to provide greater flexibility. Handheld RFID devices with Wi-Fi or cellular connectivity support baggage handlers at the apron by providing real-time data from departure control systems to indicate the status of the luggage. This use case is supported by Miami International Airport for its airline and FBO tenants operating in the apron area. Value Proposition: • Customer satisfaction. The stress of not being sure if the luggage will arrive with its owners can deteriorate the traveler’s experience. A real-time baggage tracking system along multiple tag reading points facilitated by wireless reader devices, assures travelers that their belong- ings are proceeding as they should, and if in the event one piece of luggage does not arrive, they can expect to receive their luggage shortly as the tracking system would help to locate it sooner. • Aeronautical revenue. A centralized baggage tracking system, including wireless connec- tivity anywhere from the belt systems to the airside, is an added value that can be offered to airlines to help them comply with the IATA mandate. The fees for using the service provide an additional stream of aeronautical revenue for the airport. • Reliability of operations. Having a baggage tracking system allows personnel to predict where the baggage would be at any stage in a journey. Having a system that tracks baggage along multiple reading points ensures a smooth quality of operations without any disruptions caused by lost or misplaced baggage. • Efficiency and sustainability. Using wirelessly connected RFID readers is a cost-effective way to maximize exposure of reading points for baggage with minimal investment in infra- structure. Flexible placement of RFID readers and the availability of portable readers have the potential to save airports and airlines significant costs in baggage tracking and recovery efforts. Wireless Taxiing Guidance A taxiing guidance system is a stream of colored lights throughout the centerline of the taxi- way that automatically turns on and off to guide pilots: a path of green lights on the taxiway centerline to provide the flight crew clear guidance on the directional path it must follow. If the circumstances require the flight crew to stop, the green lights will switch off and red lights will illuminate instead. Taxiing guidance systems are intended to guide pilots through the taxiways automatically without the involvement of ATC. Heathrow International Airport (LHR) uses this taxiing guid- ance system, which reduces taxiing time and improves reliability, by making the procedure easier to interpret for non-English speakers, and by providing an alternative checking system against mistakes of the flight crew or ATC. Sensors and devices, including lighting systems, have increasing wireless communication capabilities either as point-to-multipoint or mesh networks. Using point-to-multipoint allows sparsely located lighting devices to communicate actions and status to the airport network from a distant location in the airfield. Mesh PAN technologies such as Zigbee and Bluetooth Low

Taxonomy of Wireless Technologies and Their Uses in Airports 23   Energy (BLE) can establish self-configurable networks to propagate action commands from a reference location throughout the entire lighting stream without the need for any communica- tion infrastructure. This self-configurable network can also be used to monitor the status of each lighting device in the mesh. Value Proposition: • Reliability of operations. Taxiing guidance systems alleviate the need for pilots to remember and recall taxiing instructions on a congested frequency during demanding landing activities. Thus, they reduce the workload of tower controllers as well as the risk of miscommunication with pilots and the probability of runway or taxiway incursions. With wireless technologies, this type of system can be controlled and maintained remotely, providing more timely and accurate guidance actions. • Efficiency and sustainability. Using integration with the system of radars and sensors deployed throughout the airfield, which keeps track of all vehicles on the ground and calculates the most appropriate path for the aircraft to follow, taxiway guidance systems are instructed to turn on and off as needed, increasing efficiency and automation. All these sensors and lights are connected to a network for status monitoring and updating of device configurations. Wire- less communications also have the benefit of saving cable infrastructure costs and associated construction and maintenance or as a complementary communication solution to wireline networks. Connectivity of the Electronic Flight Bag (EFB) or Other Aircrew Mobile Devices An EFB is a portable electronic device that allows flight crews to do without the traditional multiple paper-based documents and charts, thereby achieving a paperless flight deck. EFBs have become an important tool for flight crews to perform various critical functions, such as basic flight planning calculations, displaying navigational charts, operational manuals, and aircraft checklists. EFB software usually runs on one or multiple tablet devices in an aircraft, installed in the flight deck, and/or used by aircrew in the cabin. Advanced EFBs can be inte- grated with the Flight Management System (auto-pilot) as a part of the avionics system of an aircraft. EFBs usually have wireless (Wi-Fi or cellular) capability and can communicate with a ground wireless network for content updates such as flight plans and navigational charts and download- ing aircraft logs after a flight. This task is usually performed at the terminal gates during aircraft turnaround and especially in the pre-flight phase. However, there is general interest from the airport community to increase the coverage so that this task can also be executed at remote park- ing locations, at maintenance facilities, and during taxi operations. Wi-Fi systems installed at ramp areas and hangars have traditionally been installed and run by the airlines operating the aircraft EFB in their own terminals at airport hubs. However, as more aircraft are equipped with these devices, the need arises to operate common-usage wireless systems to cover multiple airlines, especially when they make use of common-use gates. MIA has wireless access points (APs) deployed airside for pilots requiring connectivity for their EFBs or other mobile devices when they are at their flight decks before or after a flight. Value Proposition: • Customer satisfaction. Customers for connected EFB are airlines and aircraft operators. A reli- able common-use wireless system allows aircraft operators to conduct their tasks on the EFB without any delays or need to wait for network coverage, thus optimizing turnaround times and reducing workload. Offering this feature to operating airlines enhances the satisfaction toward

24 Transformation in Wireless Connectivity: Guide to Prepare Airports EFBs and having onboard aircraft devices at the apron is a high-value service that can be offered for a fee to customer airlines. This would generate a new stream of aeronautical revenue. • Reliability of operations. EFBs depend on wireless connectivity to synchronize with and update the most recent data available to the pilots. The timely update of critical data for the EFB is necessary for the safe planning of a smooth flight. A reliable common wireless network connection can ensure that all data and processes on an EFB work seamlessly and therefore provides reliable predictive, projective plans which ensure the safety of the intended flight. • Efficiency and sustainability. A reliable common wireless network allows pilots to plan their flights quickly and as accurately as possible, reducing turnaround time at the gate. The more reliable the network, the faster all plans can be made on the EFB for the flight to depart as less time is wasted waiting for data to load. Mobile AR for Aircraft Maintenance AR technology can provide real-time information and enhances collaboration among the workforce by making them better engaged in their work. AR can now facilitate the support of on-site personnel by offering detailed data and guidance from specialized experts. This enables hidden risks to be detected by experts (made possible by live video streaming and automated image processing on the cloud) and offers a full view of the technician’s surroundings and the environment through mobile and wearable devices. The use of AR glasses is a feature that potentially improves performance and minimizes losses during different operational tasks. Boeing uses smartAR to simplify the complex task of wire installation, which has resulted in the production time decreasing by 25%, and it has also decreased the error rates to almost zero. Value Proposition: • Aeronautical revenue. Maintenance is a significant contributing factor to aircraft operating expenses. Airlines can use mobile AR services for a fee to enhance and automate maintenance tasks. This approach to maintenance also avoids operational disruptions, though at a lower cost. Incentivizing the location of maintenance facilities at an airport will also increase land lease revenues. • Reliability of operations. Mobile AR works as a surrogate, where personnel can use AR sur- veillance to assess an aircraft rather than open the aircraft and complete all checks manually. This makes working conditions safer for personnel, as they can be less physically involved with the aircraft when doing assessments. • Efficiency and sustainability. Maintenance contributes significantly to flight delays and can- cellations. Mobile AR takes away the need and time required for personnel to manually assess an aircraft. It simplifies the complex tasks of maintenance repair and overhaul. Personnel will gain the advantage of being more flexible in carrying out tasks by using smart glasses that enable the ability to perform different tasks hands-free without distractions. This helps to decrease errors concerning procedure violations, misinterpretation of information, or insuf- ficient training. 1.1.3 Safety, Security, and Surveillance Use cases associated with safety and security include the capture and display of timely infor- mation concerning the status of activities and operations in and around the terminal and airfield. Surveillance data are used to support operational efficiency and to protect and promote the safety and security of airport users, staff, and assets. Most airport surveillance and safety equipment are wired to support effective/efficient data transfer and operations. Figure 4 depicts the use cases of safety and security applications.

Taxonomy of Wireless Technologies and Their Uses in Airports 25   Wireless Airfield Sensors Safe and secure airfield operations are supported by an airport’s ability to monitor the envi- ronment of its airfield, including air traffic (Automatic Terminal Information Service); wildlife; weather, including automated weather observing system (AWOS)/automated surface observing system (ASOS); noise; and emissions. On-site navigation and surveillance equipment, managed by the airport, the Federal Aviation Administration (FAA), or other entities (e.g., NOAA), pro- vide continuous monitoring and support of the airport airfield and surrounding airspace. Although some of these systems, such as AWOS and ASOS, broadcast automated voice mes- sages in RF for pilot information, the data gathered by many of these systems have traditionally been disseminated using wireline networks. However, long-range reliable wireless communica- tions such as cellular and AeroMACS can be deployed to enable the timely exchange of infor- mation gathered by these systems with authorized airport stakeholders and provide a common situational awareness of the airfield status. In addition, embedded LPWAN sensors can provide real-time information on the health status of the equipment from long distances. Value Proposition: • Reliability of operations. Wireless airfield sensors that provide timely information about the environment will help the airport prepare for any changes in the environment. This enhances the safety of operations occurring at the airport, as the operational procedures would account for the changes in the environment. Airport operations can be disrupted by weather condi- tions, wildlife, and hazardous events; early notifications will help the airport take corrective action to keep operations as continuous as possible. • Efficiency and sustainability. It is often perceived that airfields are too wide to adequately cover with wireless signals. However, the long-range wireless technologies described above Figure 4. Safety, security, and surveillance use cases.

26 Transformation in Wireless Connectivity: Guide to Prepare Airports are an adequate alternative to wireline infrastructure to reduce costs of construction and maintenance for connectivity with equipment in remote areas, or as a backup communica- tions link to improve reliability. In addition, deploying wireless, battery-powered sensors directly for simple monitoring tasks is a cost-efficient way to expand coverage of sensing sites in remote locations without direct access to power sources. Wireless-Based Automated Access Control The automation of access control increases security by providing a higher level of control over access to restricted areas. Automated access can also be used to secure laptops and other confi- dential or sensitive devices. Automated access to specific areas of the airport is usually supported by RFID security badges issued to permanent staff and temporary visitors. An electronic reader at the automated gate can scan the security badge and allow access based on the permissions granted to the badge. A growing trend for automated access is biometrics readers, including face, eyes, and finger- prints, among others. When a person attempts to enter a restricted area, biometrics sensors would identify the person and grant access based on their access profile. Readers can be connected to central security servers via wireless, enabling flexible deploy- ments such as access control to emergency security perimeters, or mobile controls. Police at some airports such as Los Angeles International (LAX) make use of badge validator mobile apps, to verify the validity of employee badges via random security checks in the terminal and airfield. However, due to the criticality of the security level in the information managed in these processes, only wireless technologies with strong end-to-end security such as cellular are recommended. Other access control systems work by receiving Bluetooth signals from mobile devices: a spe- cialized app installed in the mobile device may be configured to generate a Bluetooth signal that pairs with secured access devices such as door locks. Upon identification of the device, access is granted according to the permission policies for the user. Value Proposition: • Reliability of operations. Wireless-based automated access control allows airports to expand the coverage of security control points around the terminal and airfield, which enhances the scope of security activities. It also allows for better tracking of the access footprint of staff and visitors in the form of location-based reports on access history. • Efficiency and sustainability. Wireless is an alternative to wireline infrastructure, which enhances cost-efficiency and sustainability, especially for security control readers located in remote areas of the airport, or areas lacking proper communication infrastructure. Wireless Closed-Circuit Television Surveillance The use of closed-circuit television (CCTV) technology has been an integral tool in the sup- port of maintaining and enhancing security standards for decades in airports. CCTV systems consist of cameras covering the airport grounds to provide a video feed for the airport secu- rity team. CCTV has, to some degree, been implemented at virtually every public airport. This includes thermal security cameras (in use at five major Hawaiian airports), which sense activity in reduced visibility conditions. In recent years, AI applications embedded in cameras increas- ingly can interpret shapes and sounds from live video feeds and automatically report on them. Although wireless security cameras can transmit live video footage over Wi-Fi or cellular net- works, airport authorities consulted during this project expressed concern about the potential of a security breach by the introduction of a new attack vector. Airports with extensive property

Taxonomy of Wireless Technologies and Their Uses in Airports 27   and facilities also are concerned about the limitations of the existing wireless systems. In general, wireless communications are not considered the primary means to provide network coverage for cameras. However, they can be useful to cover the following use cases: backup communications link, facilitation of remote footage view, coverage for security cameras placed in locations not covered by wireline infrastructure (e.g., airfield perimeter surveillance), and quick deployment of video feeds (e.g., during incident response situations). Artificial intelligence (AI)-enabled cameras are more suitable for connection via wireless links because they do not require transmit- ting the entire footage (only alerts and associated images). Value Proposition: • Reliability of operations. Deploying wireless cameras in distant areas, especially with AI technology, has the potential to automatically perform surveillance functions around the air- port perimeter such as vehicle identification, foreign-object detection (FOD), and detection of weapons or security breaches, enhancing situational awareness and reducing time to respond. • Efficiency and sustainability. Wireless cameras avoid the deployment and maintenance of wireline infrastructure, which can be costly in distant areas of the airfield. Using wireless cameras is an incentive to find efficient solutions that reduce the number of required resources in the network. For example, if wireless thermal cameras are deployed, due to the high con- trast images extrapolated in both daytime and nighttime conditions, fewer cameras must be deployed to monitor the same region. Also, equipping cameras with AI technology has the potential of, at times, reducing the data transfer requirements. Wireless-Based Airfield Vehicle and Aircraft Surveillance Airport surface surveillance capabilities (ASSC) allow controllers to monitor ground vehicles as well as aircraft on airport surfaces, including aircraft which are on approach and departure a few miles out of the airport. ASSC is the new generation of the Airport Surface Detection Equip- ment (ASDE-X), and it is in deployment under a specific FAA program. The ASSC can combine flight plan data from surface radar, ADS-B, and multilateration sensors with position displays to produce an accurate situational awareness picture. The data extrapolated from the ASSC is disseminated to alternative FAA systems such as runway status lights and surveillance-broadcast services. The ASSC is integrated at eight U.S. airports. ASSC is supported by wireless information exchanges with installed equipment. Although ASSC and ASDE-X are specific FAA systems, they can technically share airfield sur- veillance information with the airport and other stakeholders such as airlines and FBOs operat- ing in the ramp and parking areas of the airfield, to achieve common situational awareness. The airport may also operate other aircraft and vehicle surveillance equipment on the apron, taxi, and runway areas using low-cost surveillance technologies such as GPS automatic vehicle locators, ADS-B, microwave motion sensors, and sensor loop technology (see ACRP Synthesis 12: Preventing Vehicle–Aircraft Incidents During Winter Operations and Periods of Low Visibility [Quilty 2008]). These sensors are battery-powered devices deployed in the airfield and mostly communicate via wireless technologies. Value Proposition: • Reliability of operations. The capabilities of the ASSC provide controllers with a visual indi- cator on a display of the location of all ground vehicles and aircraft on an airport’s surface. This provision of visual depictions keeps controllers better informed of the location of all vehicles within the detectable surface and therefore puts them in a position to make safer decisions. This enhances the safety of ground vehicles and aircraft, and it also allows the con- troller the ability to predict or estimate their potential positioning.

28 Transformation in Wireless Connectivity: Guide to Prepare Airports • Efficiency and sustainability. The added feature of a visual aid guidance system reduces the workload for controllers keeping track of all vehicles and their relation to each other. Wireless Virtual Ramp/Ground Traffic Control System (VRCS) FAA and ramp controllers have demanding duties for the control and management of aircraft and vehicle movement on the airfield. Virtual ramp control systems use a set of dedicated cam- eras that provide controllers with video feed coverage of any areas that may not be in their line of sight. Fort Lauderdale-Hollywood International Airport uses a wireless VRCS to enhance visibility; only 65% to 70% of the airfield could be viewed before the integration of this new system. The system combines different systems to create a graphical video stream of the airfield, terminals, gates, cargo facilities, and maintenance fields. It is a basic component for implement- ing remote ATC towers. This use case requires video cameras located in remote areas and connected via long-range wireless communications. The benefits of using wireless rather than wireline infrastructure are savings in construction and maintenance costs. However, because the VRCS is a safety-critical service, the wireless infrastructure should be very reliable and secure. Consultation with airports for this report confirms that the advantage is greater at large scales, and this application may have limited or no relevance for small hubs. Value Proposition: • Reliability of operations. VRCS offers clear viewing capabilities of all airfield areas of airports of air traffic controllers. This enhanced and on-demand capability enhances safety in ATC decision-making and the safety of airfield operations as the controller’s line of sight will be uncompromised with all blind spots being covered. • Efficiency and sustainability. Wireless-based VRCS enables cost-effective deployment and maintenance of visual awareness over challenging areas of the airfield. VRCS may also help ease the workload of controllers and enhance the quality of instructions and actions they carry out. In addition, wireless-based VRCS. Terminal Environment Sensing Sensing is critical to ensure timely surveillance of terminal facilities and early detection of emergencies. A diverse set of sensors allow controllers to monitor several terminal environment parameters such as air temperature, smoke, air quality, and sound levels. This information makes the airport security staff aware of the potential risks of emergency events such as a fire or a terror attack before they approach the area. Wireless communication enables the deployment of large-scale wireless sensor networks vir- tually anywhere in the terminal, flexibly and cost-effectively. Applying data analytics to the com- bined data variables captured by a large-scale network of wireless sensors creates the capability to detect patterns and predict occurrences of events based on big data. Furthermore, the combina- tion of many of these sensors with AI applications can help detect specific problems faster, such as the automatic detection of gunshots through sound recognition. Value Proposition: • Reliability of operations. Combined with CCTV systems, terminal environment sensors provide controllers with the terminal situational awareness they need to help them react faster to potential security and safety hazards. Terminal sensing capabilities such as gunshot detec- tion systems inform security personnel about the exact location of origin of a gunshot sound, this helps personnel to reach the correct destination fast and to resolve the situation as safely and swiftly as possible.

Taxonomy of Wireless Technologies and Their Uses in Airports 29   • Efficiency and sustainability. Using wireless connectivity for these sensors allows for a more flexible placement among the terminal building and reduces installation costs by eliminating the need for additional cabling. The flexible placement allows airports to select the optimal locations for sensors to maximize area coverage by minimizing the number of devices required. Mobile AR Surveillance Personnel in airport security offices have comprehensive location maps, but they are not integrated with the video streams captured on CCTVs. The user must look at the video and then search extensively on the map, contact the security personnel on site, and explain to them where they must go, making surveillance response procedures highly manual, which leads to misinter pretations and inefficiencies. The job is more difficult in large airports with many venues on various floors. To make the airport facilities more secure, on-site security personnel can use AR glasses to communicate the security environment of the surveilled location effectively in real time through textual and visual context information. Instead of having to rely on verbal information from their colleagues, security personnel can get actual developments as they are happening, enabling them to assess threats and respond faster. Additionally, AR tags can be attached to anything: a surveillance camera, an exit, a technical installation, or even a person. When viewing a tagged item through the AR glasses or a smart- phone, it shows all data attached to the tag. This can be text, images, or even a maintenance manual. Security personnel can use AR glasses to view relevant data about their tasks. AR could even eliminate the dependency on security rooms with lines of screens. Security personnel can instead be out on the field, entirely mobile and prepared to react. The information from an agent can be shared with any personnel, for example, security officers, operatives at a central security operations center, or law enforcement. Mobile AR surveillance can also help first responders to identify layouts of buildings, entrances, and exits, whether remotely from the operations room or locally via mobile devices, which could speed up evacuations or find people who may be trapped somewhere. Value Proposition: • Reliability of operations. Surveillance using mobile AR devices enables augmentation of the area covered, and more accuracy in the environmental awareness of events and incidents to be assessed and shared within the security team. This would allow security personnel and dispatchers to respond to threats more quickly and adequately. • Efficiency and sustainability. Mobile AR augments the capabilities and connectivity of the security agents in the field, reducing the dependency on central control rooms where all infor- mation gathered is processed. Security agents would be able to share, assess and respond to threats more effectively without the need for a centralized IT security infrastructure. 1.1.4 Autonomous Vehicles and Robotics Driverless vehicles, UAVs, and autonomous machines (robots) provide alternatives to enhance operational efficiency and increase personnel safety by automating tasks. Being mobile by design, these vehicles require wireless connectivity to receive instructions and transmit information. Autonomous vehicles and robots are equipped with cameras, sensors, and GPS to navigate with little to no human intervention. Figure 5 shows the main categories of use cases in this area.

30 Transformation in Wireless Connectivity: Guide to Prepare Airports Autonomous Surface Vehicles Autonomous transportation can be performed by different types of vehicles, including trains, buses, and trolleys. These vehicles move along predetermined paths and use a range of sen- sors including lidar, stereo cameras, inertial measurement units, radars, and GPS to navigate and detect and avert any obstacles in their path. Though the vehicle is driven autonomously, it is supervised and monitored remotely by a human controller or fleet management software through a wireless connection. 5G vehicle-to-anything connectivity capabilities are especially well-positioned for this wireless use case. In some cases, an airport staff member would be on board providing door opening/closing, troubleshooting, or guidance for passengers. Autonomous transportation for passengers, especially trains, is being tested by major airports worldwide. The innovation group at Dallas Fort Worth (DFW) contracted the EasyMile autono- mous shuttle to evaluate how this technology could transform daily operations. Denver Airport has also started trials using automated airside vehicles to shuttle airport staff across the airfield. Self-driving baggage tractors are operated via a touchscreen to select the destination and send it on its path. Likewise, driverless perimeter patrol vehicles are controlled remotely to detect humans and animals that breach the airport perimeter, as well as locate holes in the fence to alert the security team. Driverless aircraft pushback tugs allow personnel to stand by with remote control and afford more accurate maneuvering capabilities than a human driver. Other autonomous vehicles, like self-driving snowplows, follow pre-mapped routes to clear the snow in the landside parking areas as well as on airside pavement (e.g., taxiways, runways, and aprons). In this system, a fleet is led by a vehicle with a control panel and is connected through encrypted radio signals. Baggage, catering, and fuel trucks are also being considered for automation. Value Proposition: • Customer satisfaction. Autonomous transportation for passengers increases customer satis- faction as the transportation is more likely to be punctual with a reduced chance for travelers to be late. Autonomous surface vehicles RobotsUncrewed Aerial Vehicles (UAVs) Figure 5. Autonomous vehicles and robotics use cases.

Taxonomy of Wireless Technologies and Their Uses in Airports 31   • Reliability of operations. Autonomous vehicles eliminate the need for personnel to be actively involved in the manual operational activities of the airport and instead allows per- sonnel to monitor and control its activities, often from a remote post. This makes airport operations tasks safer for personnel. • Efficiency and sustainability. Autonomous surface vehicles automate operational tasks and perform them more accurately than personnel doing so manually. This reduces the need for personnel on site and out in the airfield, which increases labor efficiency. Mobile Robots Working at a faster pace and for longer periods, robots are known for improving efficiency and safety. Furthermore, the growing demand for social distancing has favored the adoption of robots, which keep airport staff separated from passengers. However, the initial investment needed to acquire them, the difficulties for some airports to find a solid return on investment on their purchase, and their immaturity in terms of dexterity, have slowed the adoption of robots by the airport community. Robots are natural users of wireless technologies. They communicate with their controllers, and in some cases with other robots, either directly through a dedicated wireless connection or through a widespread wireless network deployed within the airport. Robots can be deployed for cleaning and sanitizing airport terminals. Incheon International Airport (INC) has already begun implementing floor-polishing robots. Pittsburgh International Airport (PIT) and San Antonio International Airport (SAT) have become the first U.S. airports to use autonomous robots with ultraviolet (UV) cleaning technology. Robots can also be used to support an airport’s surveillance capabilities. Robots permanently communicate with controllers located in or outside the airport; controllers can move the robots to where they are needed to communicate with passengers and staff and contact authorities. San Diego International Airport (SAN) has been testing autonomous security robots, and LaGuardia Airport (LGA) has been employing robots to patrol Terminal B for detecting illegal parking on arrival. Finally, robots can also serve as automated mobile assistants that enhance the customer expe- rience as well as aid in terminal operations. Robots can interact with passengers and answer questions they might have about such activities as searching for a location within the airport or obtaining flight information. Automatic translation powered by AI can be of great help to tourists from different countries by processing multiple languages and addressing passengers’ queries. Robots can also serve as an entertainment source for children by interacting with them and playing videos and audio on request on attached screens. Assistant robots have already been deployed at several airports, such as Incheon International Airport (INC), Munich Airport (MUC), and Amsterdam-Schiphol Airport (AMS). Value Proposition: • Customer satisfaction. Robots expand the capabilities of a stationary information booth; they can proactively engage with passengers by approaching them instead of waiting for them to approach a stationary booth. • Reliability of operations. In contrast to traditional camera systems, which are stationary, a robot can provide more dynamic camera coverage by moving through the airport. AI technol- ogies enable these robots to automatically identify dangerous activities as well as identify faces and license plates, thereby providing their controllers with enhanced situational awareness. • Efficiency and sustainability. Apart from the standard efficiencies all robots provide, robots can automatically report the status of their processes and perform other automatic opera- tions, improving labor efficiency by reducing dependence on staff actions.

32 Transformation in Wireless Connectivity: Guide to Prepare Airports Uncrewed Aerial Vehicles (UAVs) The use of UAVs in both the commercial and defense sectors has been growing steadily. Between 2018 and 2019, small commercial UAVs, or drones, grew 40% over the previous year. Remote pilot demand is expected to require almost 350,000 remote pilots by the year 2024, which is more than a twofold increase from 2019. ACRP Research Report 212: Airports and Unmanned Aircraft Systems, Volume 2: Incorporating UAS into Airport Infrastructure—Planning Guidebook specifically addresses the integration of UAV activity in airports (Booz Allen Hamilton, Inc. 2020). Within an airport environment, UAVs can be used for carrying out inspections, providing aerial mapping, calibrating navigational aids (NAVAIDs), monitoring wildlife, or transporting assets (and potentially people in the future). Airports large and small use UAVs to support air- field construction and inspections, including Hartsfield-Jackson Atlanta International Airport (ATL), Sebring Regional Airport (SEF), and Golden Triangle Regional Airport (GTR). A more advanced application for UAVs is transportation. Airports are beginning to consider transporting goods within their grounds to speed up delivery time, safely transport hazardous elements, and reduce the inherent security risks of ground transportation. Memphis Inter- national Airport (MEM) has been conducting UAV transportation tests with the support of the U.S. DOT between 2017 and 2020 and has agreed to continue testing. In addition, the FAA is in the testing phase of regulating package delivery by UAVs through its Part 135 air carrier certification. UAVs could someday provide last-mile deliveries of packages from the airport. UAVs represent a major potential threat to airport operations. The FAA has strict proce- dures in place for UAV operators in the vicinity of airports and has implemented the Drone-ID Marking Rule requiring owners of small UAVs to display their unique FAA identifier on an external surface of the aircraft. Many UAVs have geofencing incorporated, which forbids the operation of UAVs in certain areas. Airports are actively considering the implementation of UAV countermeasures. Available commercial UAVs mostly use unlicensed wireless technology for point-to-point UAV command, control, and telemetry (Wi-Fi, BLE, and proprietary protocols) with handheld devices. Although this is acceptable for recreational UAVs, commercial UAVs, especially in an airport, should be controlled by highly reliable and secure long-range wireless communication systems. In addition, the use of unlicensed technology may interfere with the existing Wi-Fi and PAN systems in the airport and degrade their performance. The recommended technology is cellular, as it provides guaranteed latency for reliable command and control of UAVs using a dedicated frequency band. Value Proposition: • Reliability of operations. UAV inspections eliminate the need for inspectors to be physically present at dangerous heights or surrounded by aircraft and ground vehicles, thereby reducing risks to personnel. Using reliable cellular technologies maximizes control awareness of the vehicle and minimizes risks to airport operations. • Efficiency and sustainability. UAVs provide a more dynamic observation platform by sup- porting a diverse set of sensors (like cameras, lasers, and infrared) and allowing the inspector to move around the inspected target. UAVs also save time in inspection preparations and money on staff insurance. Cellular systems allow controllers to perform their duties from the operations room, located in the airport or beyond, using the private or mobile carrier cellular network, instead of requiring a radio line-of-sight (LOS) using a handheld device. 1.1.5 Incident Response and Recovery Integrated incident response is a critical process to address hazards in the airport landside or airside (e.g., aircraft accidents, fire, or terror attacks). Although hazard mitigation is addressed

Taxonomy of Wireless Technologies and Their Uses in Airports 33   by surveillance applications, this section consolidates different wireless applications that allow the competent authorities in the airport to react effectively when an incident occurs. Quick, dynamic, and effective incident response requires the presence of personnel in or near the area of the incident. This environment calls for wireless communication technologies, which allow rapid deployment of connectivity areas supporting situational awareness, tactical com- munications, and information recording. Figure 6 depicts the wireless use cases in this category. Radio Communications for First Response Teams During an incident, coordinated teams of first responders are deployed quickly on the ground for response and mitigation. These teams may be composed of individuals and/or vehicles and need to be equipped with highly reliable communication capabilities for coordination with the team and sharing of timely information about the incident status and rescue/recovery actions. First responder teams can communicate via direct voice or message channels or use network relays to cover the incident zone. Relays can include fast-deployment communication equipment or vehicle-mounted mobile command centers which create a communication coverage spot cov- ering the platoon members deployed in the area. At a minimum, voice capabilities are required for tactical communications. Often, higher bandwidth applications including medical assessments, or airport GIS updates (e.g., obstacles) are required to share awareness of the incident and victim status with other members of the team, or with a command center located in the airport or outside. In the latter case, the team needs to rely on a communication link with the backbone network to be able to disseminate this data and ingest real-time information updates from command centers such as mission dispatches and GIS maps, and coordinate safety agencies on the ground, or social media analysis applications. Figure 6. Incident response and recovery use cases.

34 Transformation in Wireless Connectivity: Guide to Prepare Airports Value Proposition: • Reliability of operations. An enhanced means of communication allows for better coordi- nation of tasks in time-critical responses to incidents. This enhanced quality of coordination increases the capability to mitigate safety threats and reduce disruptions and makes working conditions safer for first responders. • Efficiency and sustainability. Enhanced communications allow for incidents to be mitigated and resolved faster than usual and even reduce the number of personnel on the ground. As a result, operations can resume sooner without disruptions. First Responder Personal Protection When an incident occurs, first responders are the primary personnel to move into the scene to mitigate any potential damages and rescue individuals. As such, first responders risk their lives to control the consequences of an incident. To enhance the safety of those risking their lives, wearable sensing technology can be leveraged to disseminate first responder sta- tus. Sensor technologies for first responder protection are a priority in the research promoted by the National Institute of Standards and Technology (NIST) Public Safety Communications Research Division. Wearable sensors monitor the first responder agent’s vital signs, such as heart rate, oxygen level, and more. The first responder location needs to be shared in real time for coordination and rescue operations if needed. In addition, environmental data including temperature and air quality are required to trigger a hazardous situation alert. This is a challenging environment where the only ideal candidate to provide wide range, high density, and low power for portable devices is cellular LPWAN and its protocols. Value Proposition: • Customer satisfaction. As airport stakeholders, first responder authorities highly value systems that ensure the safety of the lives of their personnel. The airport can then be perceived as an environment ideally equipped for safety agencies operating in the area. • Reliability of operations. This use case enhances the awareness of the conditions under which first responders work. This allows the first responders’ tasks to be more controlled by leaders from a remote location. As a result, the first responders can work to mitigate hazards under safer conditions. Wireless Real-Time Surveillance for Incident Investigation In an incident, the events taking place occur so quickly that recollecting and manually stream- ing through hours of video footage can be daunting tasks that require multiple personnel. These security surveillance challenges are being tackled with the help of data-driven technology and AI. One such new application is video content analytics (VCA) technology, which allows airports to expedite footage investigation and enhance situational awareness with the additional benefit of extrapolating operational intelligence from the footage. Data-driven incident investigation requires an effective process to capture and process large volumes of information for further investigation and forensics. This information may be extracted from video feeds and sensor feeds present in the incident area. However, there is the risk that these data are not accurate enough because the equipment does not specifically cover the affected area, or the infrastructure may be affected by the incident. On-demand surveillance (video and sensor) equipment, including body cameras carried by first responder agents, is often used in the field to augment the amount and quality of data captured about the incident. In addition, surveil- lance devices equipped with wireless communication capabilities may transmit the captured data in real time to avoid the risk of loss during the incident.

Taxonomy of Wireless Technologies and Their Uses in Airports 35   Value Proposition: • Reliability of operations. This use case provides enhanced awareness of the sequence of events during an incident or accident. Enhanced awareness of the events allows for more appropriate decisions to be made, which increases the overall safety of operations during an incident. In addition, this use case provides critical material for post-incident analysis to speed recovery and improve future responses. • Efficiency and sustainability. Enhanced awareness allows for mitigative decisions to be made accurately and on time. The appropriate resources in the incident area can be allocated effec- tively, maximizing positive results. 1.1.6 Travel Health The COVID-19 pandemic has put a spotlight on the need for various safety measures related to the health of passengers, employees, and general users. Wireless monitoring and temperature check systems could support some of these efforts. The following use cases have been considered (Figure 7). However, in the current changing environment, it is still not clear at this point to what extent they will become relevant in the long term. Wireless-Based Social Distance Monitoring Social distancing has become a major advisory around the globe as a means of mitigating the spread of COVID-19. Virtual queueing and passenger density management is a recent technol- ogy that tracks movement and uses machine learning to produce real-time and predictive den- sity insights that would help airports manage passenger traffic in terminals. Moreover, it enables travelers to pre-book slots at security checkpoints instead of waiting in line. Miami International Figure 7. Travel health use cases.

36 Transformation in Wireless Connectivity: Guide to Prepare Airports Airport is one of the airports using motion analytics technology called “safe distance” to monitor social distancing via the tracking of smartphone locations. Lidar and passenger flow analytics are also positioned as technologies that monitor crowds gathering in a particular area and compliance with social distancing requirements. Potentially, any of these technologies could share real-time monitoring information by wireless links with the network to facilitate quick and cost-effective deployment. They can be used to convey the safety of specific airport areas through dynamic signage for passengers, as is being tested in Orlando International Airport (MCO). Value Proposition: • Reliability of operations. This use case helps to increase the safety level of the traveling public. It ensures that a safe distance is kept among travelers to mitigate any chance of contracting COVID-19. Wireless-Based Automatic Passenger Temperature Screening One of the identified possible symptoms of people suffering from COVID-19 is high body temperature (fever). As a result, thermal screening technology has been considered for deploy- ment at airports to screen large volumes of travelers. The camera detection system in this tech- nology can monitor the temperature of multiple travelers moving along the terminal without any physical contact that may put employees at risk. Los Angeles International (LAX) and London Heathrow (LHR) are using thermal cameras to screen passengers for COVID-19. After analyzing this use case, considering that only a small percentage of people infected with COVID-19 develop high body temperatures, the industry seems unlikely to adopt this technol- ogy because it does not prevent the spread of the disease. Furthermore, as many other medical situations could cause fever, there is a high risk of false positives. Value Proposition: • Reliability of operations. This use case can increase the safety of passengers as well as airport staff. Prescreening travelers for symptoms of COVID-19 can help airports to recommend travelers for testing and to isolate them in case of a positive test. However, it does not provide a definitive barrier to the spread of diseases. • Efficiency and sustainability. Using wireless thermal cameras allows quick deployment in temperature control areas without the need for additional staff or cable infrastructure. Touchless Travel Touchless travel, or the aggregate capabilities to minimize the number of touchpoints of a passenger in airport facilities, a growing trend before COVID-19, has been accelerated by the pandemic. Touchless can apply to all activities that are part of the passenger experience in the airport, including self-service, item ordering, and payment as indicated above, but also others like smart restrooms. Two technologies will make touchless travel possible. Smartphone-centric applications using mobile Wi-Fi or cellular connectivity enable the execution of passenger-processing tasks such as check-in, bag-dropping, and checkpoint identification. Passive tasks are enabled by smart building actuators that facilitate passenger services without active participation on their part; examples include smart restrooms, elevators, and doors. Value Proposition: • Customer satisfaction. This use case will help bolster traveler confidence in air travel as it will show the travelers that they are at minimal risk of exposure to COVID-19 and other diseases.

Taxonomy of Wireless Technologies and Their Uses in Airports 37   • Efficiency and sustainability. This use case can help to reduce the number of airport staff required to interact with and assist travelers during their travel experience at the airport. These human resources can be reallocated for more critical or heavy workload tasks which need more human resource support. Wireless-Based Staff Contact Tracing Contact tracing is commonly accepted as one of the most effective ways to detect and miti- gate the spread of COVID-19. Basic contact tracing is now implemented by airlines in the form of passenger location forms and attestations. Mobile contact tracing, using Bluetooth-enabled smartphone communication, is still emerging and is not expected to reach the high levels of accuracy required to be effective in airport facilities. In addition, it is difficult if not impossible for airports to access personal data from visiting passengers, which makes the contact tracing virtually unfeasible. Airport organizations, including airport operators and tenants, can perform contact tracing among their employees. Being properly identified, and often carrying an enterprise-provided mobile device, it is possible to record historical data of the whereabouts of employees when working in the airport facilities. This information can greatly help perform some level of contact tracing inside the airport facilities. Value Proposition: • Customer satisfaction. Travelers highly value the fact that airports are actively monitoring the COVID-19 transmission in their working staff. This will help to increase travelers’ confi- dence in air travel concerning the safety of their health. • Reliability of operations. This use case will help to ensure the safety of the airport staff who work on site. Contact tracing will help to inform the airport on who has been exposed to the infected employee and this will also allow the airport to take mitigative steps. • Efficiency and sustainability. Contact tracing allows airport authorities and tenants to arrange for other staff to take over the shift of the infected employee to ensure continual operations with minimal disruptions. This can be all done automatically via tracking apps, which record the location history of staff, without the need for costly and inaccurate surveys. 1.2 Characterization of Wireless Technologies 1.2.1 Description of Wireless Technologies This section introduces the main types of wireless technologies available (Table 3) and com- pares their most relevant characteristics. It describes the background, history, level of maturity, main characteristics, and reference architectures for each technology. Appendix B provides a detailed taxonomy for wireless technologies that quantifies the characteristics and allows for quantitative comparison. Technology type Relevant technology standards Cellular 4G/Long-Term Evolution (LTE), 5G Wi-Fi Wi-Fi 4/5, Wi-Fi 6, Wi-Fi 6E, WiGig WiMAX AeroMACS Land mobile radio P25, TETRA, analog FM Low-power wide-area networks (LPWANs) in unlicensed spectrum LoRa, Sigfox, HaLow Personal area networks Bluetooth, Zigbee, Ultra-wideband (UWB) Radio-frequency identification (RFID) RFID, NFC Table 3. Summary of wireless technologies.

38 Transformation in Wireless Connectivity: Guide to Prepare Airports 1.2.1.1 Cellular Technologies Cellular communications are designed for wide-area networks (WANs) whose access commu- nication link is wireless and supports device mobility (Figure 8). They generally use frequency bands exclusively licensed to an operator for a specific coverage area and may have multiple operators with wireless service in the same area. The RAN provides network access to user equip- ment, which can be mobile devices or objects such as sensors. The RAN coverage area is served by base stations that typically have multiple sectors, or cells, transmitting in separate frequen- cies. The core network supports end-to-end services such as voice and data traffic transmission, subscriber management, network security, and traffic management. Cellular networks provide connectivity to the public internet or other enterprise networks. Cellular RAN can support the three architecture models described in Section 1.2.4. Public cellular networks are operated nationwide by mobile carriers for commercial purposes or public- safety communications (e.g., FirstNet). DAS, managed by neutral-host providers, enable high- capacity communications with mobile carrier services for users in dense indoor spaces, where public cellular signal shows degraded performance. Finally, private cellular networks are emerg- ing as an enterprise purpose-built solution for venue managers to enable reliable, secure com- munications for critical business operations. Cellular communication protocols and architectures are standardized by the 3rd Generation Partnership Project (3GPP), whose members include service operators and equipment vendors. 3GPP maintains multiple generations of cellular technologies: • 2G and 3G. These are legacy technologies that still provide wide-area coverage, used for voice calls and limited data rates (approximately 64 kbps and approximately 20 Mbps, maximum, respectively). Eventually, these networks will be phased out and replaced, but more advanced generations and spectrum will be re-farmed, which in the United States is expected to be Figure 8. Cellular network (4G/LTE and 5G) architecture.

Taxonomy of Wireless Technologies and Their Uses in Airports 39   completed at the end of 2022. As a result of the phase-out schedule, there will be less imple- mentation of 2G or 3G at this time. • 4G/LTE (Long-Term Evolution). This cellular technology carries most data traffic today and covers over 90% of the U.S. population. It is the first cellular generation to support mobile broadband (approximately 100 Mbps, maximum), including video, in a scalable and reliable way. • 5G. This is the latest commercially available generation being deployed by mobile carriers. In the future, enterprises and other service providers (e.g., cable operators) are likely to deploy 5G as a unified platform of mobile applications with customized requirements. 5G brings an expansion in the spectrum available to cellular technology, ultra-low latency, and massive IoT, and it will increase mobile network capacity (approximately 1 Gbps). • 6G. The future generation of wireless technology is under development to improve 5G per- formance, reliability, and security. It is expected to reach data rates of 100 Gbps and to be commercially available in 2030. This guide focuses on the transition from 4G to 5G, as both will be the most relevant cellular technologies in the short-to-medium timeframe. 4G will be the prevalent cellular technology for some years, although operators have started to roll out 5G mostly as a non-stand-alone (NSA) network—a 5G RAN that uses the existing 4G Core Network (Figure 9). New stand-alone (SA) 5G network deployments are growing and expected to surpass new NSA deployments by 2023 (Hines and Pringle 2020). To guarantee service continuity during the transition in the United States, and accommodate mobile subscribers (e.g., passengers) from countries slower in 5G adoption, coexistence is expected for a long time. 4G/5G coexistence is also supported in the same frequency band and space thanks to dynamic spectrum-sharing, as an intermediate step toward spectrum re-farming. By 2024, 63% of the smartphones in the U.S. market will be 5G capable (Ericsson 2019). According to Markets and Markets (2020), the drivers for evolving cellular infrastructure to 5G in airports will be the need for fast sharing of real-time data about baggage and gate opera- tions, the introduction of automated vehicles, the rising demand for good voice communication and high-speed internet connection by passengers, and the increase in smart connected air- ports. Importantly, 5G also supports low-data-rate applications executed by very high volumes of devices. These needs for bandwidth flexibility and network scalability are the foundation of the IoT, which is an emerging set of use cases both in the terminal and airfield. Because of these varying requirements, 5G performance is defined for three usage scenarios: • Enhanced mobile broadband (eMBB). High data rates for mobile applications that use video or have high data volume requirements, higher capacity, spectrum efficiency, and network energy efficiency. • Massive machine-type communications (mMTC). The ability to support massive connec- tivity to a high number and density of devices, with low costs, low-power consumption, and long range. Figure 9. Non–stand-alone (left) vs. stand-alone (right) 5G rollout.

40 Transformation in Wireless Connectivity: Guide to Prepare Airports • Ultra-reliable low-latency communications (URLLC). Lower latency and jitter, determin- istic behavior, higher reliability, and resiliency to support critical machine-type communica- tions in mobile environments, including mission-critical and safety applications, industrial automation, and autonomous vehicles. Cellular communications support two families of low-power wide-area networks (LPWANs) with built-in 5G for the IoT. These have been supported by LTE since Release 13. Both are scal- able, low-cost IoT options that can be supported over an existing cellular network providing coverage reliability and service continuity. The latest Release 16 supports forward integration of both options in future 5G: • The primary use for narrowband IoT (NB-IoT) is for massive IoT networks that require a long battery life of 10 or more years and large coverage areas. The long battery life is achieved through minimal data transfer and stationary applications. The data rate is in the kbps range. • eMTC (extended machine-type communications) is the initial version of 5G mMTC and provides higher capabilities in terms of data volume, latency, and security for mobile data and voice applications. Commercialization of the initial 5G new radio (5G NR) RAN, standardized in 3GPP Release 15, began in early 2019. Initial 5G NSA launches deliver only eMBB. Release 16 (2020) and Release 17 (2022) include better support for industrial applications and enterprise private networks (5G Americas 2020), including improved URLLC and time-sensitive networking, support for unlicensed spectrum, improved mMTC for massive IoT, location accuracy, and vehicle-to- everything communications. Future releases will expand the support for vertical use cases and new spectrum bands, and further improve latency, security, reliability, traffic capacity, spectrum efficiency, and location accuracy. The 5G core network redefines cellular architecture to take advantage of cloud-native con- cepts, software-defined networking (SDN), and virtualization. Network, computing, and storage functions interact adaptively as microservices in an automated and scalable manner, instead of being fixed functional entities. This enables an elastic environment where resources are software elements dynamically instantiated across the network, enabling cloud and edge native archi- tectures. Although these capabilities may be limited in NSA 5G deployments using 4G core networks, SA 5G deployments allow the full migration to a service-oriented architecture (SOA) and support advanced producer-consumer model features, especially network slicing. Network slicing partitions the physical 5G network infrastructure at the end-to-end level into independent, virtualized logical networks with different requirements and levels of pri- ority (Figure 10). Each network slice is a self-sufficient container with all the functions and resources required for independent service. This allows optimum configuration of all the net- work resources for traffic groups according to different business purposes. This network as a service (NaaS) model grants customers the power to configure their network slice to their needs, or create one on demand, without prior reprovisioning by the network operator, increasing cost- efficiency and deployment agility for mobile services. Integrated access and backhaul, introduced in Release 16, allows the use of 5G as a transport network to expand coverage instead of densifying the fiber transport network. This increases network flexibility and cost-efficiency, especially for very dense network deployments such as small cells, by reducing the need for fiber to each cell site to quickly expand coverage and capacity or bridge from outdoor to indoor. Cellular technologies are also appropriate to provide wideband communications for public- safety agencies. The FirstNet network provides such a reliable network for first responders and law enforcement agencies, leveraging incremental capabilities in LTE and soon, 5G. Releases 12 to 14 introduced cellular mission-critical capabilities, including one-to-one and one-to-many

Taxonomy of Wireless Technologies and Their Uses in Airports 41   mission-critical push-to-talk communications, mission-critical video, and mission-critical data with built-in prioritization over consumer applications. Isolated operations allow cell sites to continue oering services even with the loss of backhaul connectivity. Proximity-based services enable devices to communicate directly (sidelink), independent of the network, and to relay communications for out-of-coverage devices, such as those inside a building. Cellular networks can also use unlicensed frequency bands, shared with Wi-Fi networks. is allows core network integration of applications (e.g., Wi-Fi calling), smart load balance between both networks, and simultaneous cellular/Wi-Fi connection down to the user equip- ment. In 4G, cellular unlicensed access has been available mostly for mobile operators as an expansion of licensed spectrum, called License-Assisted Access (LAA). e use of both licensed and unlicensed spectrum allows for more exibility in coverage depending on the available oper- ator’s spectrum and real-time demand in the network. Strengths and Limitations. Cellular technologies have the strength of being supported by open, non-proprietary standards with increasing vendor interoperability, which drives a large- volume ecosystem and ample solutions. is facilitates virtualization and digital transforma- tion, giving operators the ability to use o-the-shelf hardware and SOA, increased exibility, and agility in deployments. With edge computing and network slicing, 5G enables operators and users to manage enterprise services and applications on the premises or in the cloud. Cel- lular technologies allow for dynamic network provisions to support a wide range of use cases, including IoT. Cellular radio stations have the exibility to be congured as macro cells, small cells, or DAS. Small cells are low-powered radio access nodes that oer certain benets, such as improved capacity in areas with high user densities. DAS allow sharing of a common small-cell infrastruc- ture among mobile operators in the same building. Cellular technology also provides exibility in high-throughput and LPWAN (IoT) applications on devices served by the same network. Security is built in, with improved cyber threat intelligence, enhanced authentication, and the ability to manage user and IoT devices within a network. Network slicing enables the isolation of users and services and the mitigation of risks because disruptions in one logical network do not aect other tenants in the physical infrastructure. Cellular deployments can use licensed or unli- censed bands. When using licensed bands, they have the benet of reliability. Cellular networks can also cooperate with Wi-Fi networks to harness capacity in unlicensed spectra. Figure 10. 5G network slicing.

42 Transformation in Wireless Connectivity: Guide to Prepare Airports As a limitation, virtually all cellular communications are provided by mobile carriers with exclusive licenses to frequency bands; thus, using this technology creates a dependence on these carriers and their respective decisions on how to use this spectrum (e.g., see the discus- sion of 5G near airports in Section 1.2.3). Because of this limitation, some venue owners use mobile carrier networks directly as subscribers, though access may be expensive (especially for bandwidth-intensive applications), or on a best-effort basis (difficult to enforce service level agreements and to control performance). Also as a consequence, virtually all mobile devices and an increasing number of wearables support cellular devices; however, that is not the case for stationary devices such as laptops or workstations. IoT devices using a cellular LPWAN may only be supported on a specific carrier network and may not be interchangeable between opera- tors, and signal coverage may not be ensured over areas with extended surfaces or challenging propagation environments. New business models are evolving to support private networks over cellular technology. Mobile carriers offer deployment and management of private networks for venue owners. The emerging availability of an unlicensed and shared spectrum for mobile applications such as Citizens Broadband Radio Service (CBRS) affords larger organizations the option to deploy and manage the network by themselves. However, cellular networks are costly to deploy, complex, and difficult to scale compared with Wi-Fi, and the availability of products and expertise for enterprises is limited. Mobile carrier networks are not planned for indoor spaces, often leading to poor coverage quality inside large buildings, which operators may not improve if there is no business case. This is expected to be particularly the case for 5G, as it introduces new frequency bands in the higher end of the spectrum, which are more sensitive to building obstacles and materials that degrade the signal. New architectures are being considered by venue managers, including airports, to improve indoor signal coverage, including DAS and Wi-Fi roaming. 1.2.1.2 Wi-Fi Wi-Fi is a mature technology that has been used for more than 20 years. The Institute of Elec- trical and Electronics Engineers (IEEE) developed the IEEE 802.11 family of standards as a wire- less alternative to Ethernet for local area networks (LANs). The Wi-Fi Alliance defines product generations and capabilities based on IEEE 802.11 protocols, with the largest commercial version (Wi-Fi 6) based on IEEE 802.11ax. The Wi-Fi Alliance certifies Wi-Fi products for conformity to the standards and interoperability. The Wireless Broadband Alliance (WBA) is an industry organization that promotes interoperability initiatives to facilitate the adoption of Wi-Fi across different deployment architectures, business models, and use cases. Wi-Fi is a ubiquitous wireless access technology, with a huge ecosystem, economies of scale, solid interoperability, and good scalability to transport large amounts of traffic. Most of the deployed Wi-Fi infrastructure today uses Wi-Fi 4 and 5, but Wi-Fi 6 deployments are rapidly expanding. Wi-Fi 6 provides an increased data rate of 9.6 Gbps (although typically 2 Gbps is perceived by the end user in a normal environment), better performance in crowded environ- ments, and better power efficiency. Because Wi-Fi is backward-compatible and updates follow enterprise and home technology refresh cycles, adoption of Wi-Fi 6 will be gradual and will coexist with Wi-Fi 4/Wi-Fi 5 devices and infrastructure for years to come. It is estimated that by 2022, over 56% of Wi-Fi devices will support Wi-Fi 6 (Hetting 2018). As Wi-Fi 6 adoption continues to grow, work has started on Wi-Fi 7, which promises to provide higher data rates, lower latency, higher spectrum, cost and power efficiency, better interference mitigation, and higher density of networks and devices. IEEE plans to publish the amendment

Taxonomy of Wireless Technologies and Their Uses in Airports 43   by mid-2024, and certified products and commercial equipment should be available soon after- ward. In addition, two other technologies maintained by the Wi-Fi Alliance are emerging: • HaLow, based on IEEE 802.11ah, has recently been launched to use Wi-Fi technology to sup- port long-range, low-power, low-bandwidth IoT services. HaLow is based on Wi-Fi 4 and uses a sub-1 GHz spectrum. It uses narrow frequency channels to reach terminal devices at 1 km or more (10 times more than the reach of Wi-Fi in the 2.4-GHz band) for relatively high data rates, up to 1 Mbps, and a years-long battery life. These characteristics place it within the category of unlicensed LPWAN (see Section 1.2.1.5). • WiGig, launched in 2016, is based on IEEE 802.11ad and uses the 60-GHz band to provide short-range, high-throughput connectivity (7 Gbps up to 10 meters) at a very low cost, with low latency and power consumption. WiGig has the potential to expand with the next genera- tion based on IEEE 802.11ay, supporting up to 40 Gbps. Because of its simplicity of use, configurability, and scalability, Wi-Fi is the preferred solution to provide connectivity to LAN and internet access in public venues, both for enterprise services and guest access (Figure 11). Wi-Fi networks generally use unlicensed frequency bands, which makes them affordable to enterprise and home users alike. Wi-Fi APs provide network access to Wi-Fi devices through a managed wireless interface and support network connectivity through a wireline or wireless backhaul. Wi-Fi supports mechanisms to extend coverage without addi- tional wiring by relying on existing APs using either Wireless Distribution System (WDS) or Mesh. However, both significantly hinder the capacity of the air interface. Each AP can expose more than one service set identifier (SSID) that configures a network name, security, and traffic policy configurations for its connected users. Airports have limited influence on and perform limited monitoring of tenants using unlicensed bands. Thus, for spaces with high user density and performance, careful network planning is Figure 11. Wireless LAN (Wi-Fi) architecture.

44 Transformation in Wireless Connectivity: Guide to Prepare Airports necessary to ensure acceptable coverage and capacity for all users, configure appropriate traffic management policies, and mitigate interference among APs or with neighboring networks operat- ing at the same frequency. This specific topic is addressed in ACRP Report 127: A Guidebook for Mitigating Disruptive WiFi Interference at Airports (Carroll et al. 2015). Wi-Fi networks can be shared by enterprise users and visitors within the venue premises. This creates challenges for user management and makes access to the network less convenient; examples include providing seamless access to visitors while ensuring secure authentication or ensuring that enterprise users access trusted networks when outside the premises. OpenRoaming, a set of industry standards from the WBA, solves this problem through the Wi-Fi Alliance- certified Passpoint mechanism. Passpoint is an industry solution supported by most Wi-Fi AP and devices in the market, simplifying online signup of users and eliminating the need to dis- cover, select, and authenticate in a Wi-Fi network each time they visit. OpenRoaming establishes a roaming federation of Wi-Fi network operators (including enter- prises and venues) and identity providers (trusted entities that manage user credentials, such as mobile carriers), in which the WBA acts as the ecosystem policy authority. An enterprise may be an identity provider for its users or collaborate with an identity provider to give access to its users outside its network. By participating in the federation, different providers can share credentials. As a result, the enterprise can provide seamless connectivity for mobile subscribers when inside the building’s Wi-Fi coverage area and according to the enterprise security policy. OpenRoaming unlocks new business models for participating enterprises and venue managers. Leveraging this federated platform, venue managers can build Wi-Fi capacity, set up a fee policy, and sell this capacity back to carriers to provide access to subscribers who are on the premises. Strengths and Limitations. The main strength of Wi-Fi is that it is the wireless technology that enterprises and venue owners have most widely adopted in their private networks, used both for connectivity to their employees, tenants, and visitors and for IoT applications and devices. Wi-Fi is by far the most widely used wireless technology: It will account for 57% of global inter- net traffic and 72% of wireless traffic by 2022. Wi-Fi wins in terms of simplicity, scalability, and traffic density in confined spaces. With the transition to Wi-Fi 6, Wi-Fi capability and performance have improved, bringing them technologically closer to 3GPP technologies such as 5G while preserving Wi-Fi’s simple deployment and operation and its ability to operate in unlicensed bands. Therefore, 5G may complement Wi-Fi, but it is unlikely to challenge its role in providing connectivity in residential and business environments, especially in indoor locations. In addition, Wi-Fi networks can provide room to meter-level location accuracy with firmware upgrades, which most commercial APs support. The location accuracy depends on the AP den- sity, and the bandwidth available to use (i.e., 5 and 6 GHz frequencies allow wider bandwidth). However, Wi-Fi can only locate and track electronic devices, with tags not being a viable option for general asset tracking due to their cost. Wi-Fi has limitations. Spectrum utilization is high for Wi-Fi because everyone can use it on unlicensed frequencies in the 2.4- and 5-GHz bands, and it can be densely deployed with high spectrum reuse. This hinders Wi-Fi’s performance: When traffic demand is high, Wi-Fi networks may become congested and prone to interference, and enterprises or homeowners cannot block interference because they do not control the spectrum. With the addition of the 6-GHz band, the capacity of Wi-Fi will more than double and the lower contention in the band will make Wi-Fi better suited to applications that require tight time management, such as cloud-based AR. Wi-Fi is not optimal for all IoT applications. Although it is used to connect wireless sensor networks, it is designed for high-capacity communications, which inherently consume more

Taxonomy of Wireless Technologies and Their Uses in Airports 45   energy. Thus, Wi-Fi devices require continuous battery charging or power input. In addition, as IoT networks scale to thousands or millions of devices, Wi-Fi shows its limitations as it can only effectively manage a limited number of users. Wi-Fi coverage range limits its applicability to indoor or campus environments. Sharp drops in signal strength due to low transmit power levels make Wi-Fi unsuited for wide-area coverage because gaps over large areas are unavoidable. A specific example in airports is the challenge of coverage under aircraft wings for maintenance operations in apron or parking areas. Although Wi-Fi is scalable due to the relatively low cost to relocate or add APs to the network, Wi-Fi net- work planning requires specialized labor for siting and calibration, making the cost of a network modification non-negligible. Wi-Fi is also not designed for high mobility, as handover between APs does not reliably work when the device moves at near vehicular speed. In addition, Wi-Fi cannot compete in sensor network applications in terms of energy efficiency, range, and reliability with other IoT-specific technologies. Specifically, both HaLow and WiGig technologies have only been recently launched. There- fore, the performance and applicability of these technologies compared to competing options cannot be assessed yet and market risk is still high. 1.2.1.3 Aeronautical Mobile Airport Communications System (AeroMACS) AeroMACS is a technology specifically designed for the aviation industry. AeroMACS enhances communications on the airport surface by providing improved transmission of Air Traffic Control (ATC) and airline operations communications. AeroMACS is an aviation industry standard based on IEEE 802.16-2009, which supports mobility and wireless broadband standards for internet protocol connectivity in metropolitan area networks (MANs). The AeroMACS standard is maintained and certified by the WiMAX Forum, an industry orga- nization that also promotes IEEE 802.16 standards in other market verticals such as telecommu- nications and energy. AeroMACS is also a standard supported by the International Civil Aviation Organization (ICAO) and the Radio Technical Commission for Aeronautics (RTCA), which specify the communication profiles and performance requirements for the use of AeroMACS in support of aviation safety applications. The spectrum for AeroMACS in the 5-GHz band is glob- ally reserved by the International Telecommunication Union for aviation safety applications and governed by a specific aviation spectrum manager appointed by FAA. An AeroMACS RAN, called the Access Service Network (ASN), is composed of one or sev- eral base stations providing air interface access to mobile or fixed wireless subscribers operating within the airport perimeter (Figure 12). AeroMACS supports data exchange confidentiality and integrity and Public Key Infrastructure (PKI) user authentication. It also supports traffic prioritization and quality of service (QoS) for mission-critical applications. It is designed as a cost-effective flexible alternative to wireline infrastructure while providing very robust levels of security and reliability. FAA considers AeroMACS key to assisting airports in relieving airport surface traffic, conges- tion, and delays, and it is in the agency technology roadmap as the primary means of commu- nication for airport critical communications at least until 2036 (FAA/SESAR 2018). AeroMACS is an integral part of the FAA Telecommunications Infrastructure (FTI), being deployed for the FAA ASSC program, and is being considered as a solution to relieve congested very-high- frequency (VHF) spectrum for air traffic and airline communications at airports. Strengths and Limitations. The main strengths of AeroMACS are its reserved spectrum and certificate-based PKI credentials, which make it appropriate for mission-critical services. AeroMACS is a technology supported by global standards for interoperability, and dedicated to

46 Transformation in Wireless Connectivity: Guide to Prepare Airports safety use, using a dedicated spectrum not shared with consumer applications. The long coverage range and high bandwidth with QoS make it suitable for a range of applications over long dis- tances. AeroMACS can cover an entire airfield with a few base stations, servicing mobile and fixed devices with different levels of service depending on user and application (e.g., many IoT devices under long distances with low-data rate, high-resolution video cameras under short/ long distances, and mobile users requiring connectivity and streaming content at varying data rates). In addition, the technology is prepared to support AeroMACS-equipped aircraft when available, although long aircraft life cycles and costly avionics certification processes are delaying the adoption of this technology by airlines. Another strength of AeroMACS compared to Wi-Fi is that it performs well in high mobility scenarios—in this sense, AeroMACS performance is comparable to cellular. Handover within the ASN is managed by the base stations, not by the subscriber as in Wi-Fi, which ensures there is no session break in real-time applications in high mobility. On the other side, AeroMACS allows the creation of a cellular-performance level private network at a fraction of the cost (although cellular private networks in a shared spectrum may have a comparable cost). The limitation in terms of performance is that AeroMACS is not suitable for indoor applica- tions due to the high-frequency range and limited network density, although it does support some degree of non–line-of-sight (NLOS) propagation. This limitation makes it suboptimal for applications that require terminal coverage, although they are possible with additional planning or infrastructure. In terms of technology risk, the supplier ecosystem is small because it is a niche market and has not yet reached commercial maturity. Another downside is the cost of mobile devices, which is much higher than that of other technologies, mostly because these devices are sold as ruggedized units. 1.2.1.4 Land Mobile Radio (LMR) An LMR system is a person-to-person communication system consisting of two-way radio transceivers that can be stationary (base station units), mobile (installed in vehicles), or portable (handheld walkie-talkies). Most systems are half-duplex, with groups of radios sharing a single radio channel (Figure 13), which means only one radio can transmit at a time in a channel using Figure 12. AeroMACS architecture.

Taxonomy of Wireless Technologies and Their Uses in Airports 47   Push-To-Talk (PTT). ere are two LMR technologies available in the United States, both of which are open standards and digital: • Project 25 (P25 or APCO-25) is a suite of standards for digital mobile radio communications designed for use by public-safety organizations in the wake of 9/11. P25 radios are a direct replacement for analog radios but add the ability to transfer data as well as voice, allowing for more natural implementations of encryption and text messaging. P25 radios are commonly implemented by dispatch organizations, such as police, re, emergency medical service, and emergency rescue service, using vehicle-mounted radios combined with handheld walkie- talkie use, but have also been selected and deployed in other private systems. P25 is optimized for wider area coverage with low population density and supports simulcast. P25 has, how- ever, limited capacity for data transfer. • TETRA is an open-standard digital radio communications technology that oers fast and secure communication with a wide range of telephone-like voice and data services. TETRA is optimized for high population density areas due to the higher spectrum eciency. It can sup- port full-duplex voice communication, data, and messaging, but does not provide simulcast. Most P25 networks are based in Northern America, where they have the same coverage and frequency bandwidth as earlier analog systems. Both P25 and TETRA can oer varying degrees of functionality, depending on the available radio spectrum, terrain, and project budget. P25 may be used in the conventional talk-around mode without any intervening equipment between two radios (o-network), where the two radios communicate through a repeater or base station without trunking, or in a trunked mode where trac is automatically assigned to one or more voice channels by a repeater or base station. e latter is better for larger organizations (those with 300 employees or more). TETRA only supports trunked communications. Strengths and Limitations. Regarding strengths, LMR equipment has some of the best coverage of any wireless communications technology, with very large cell sizes, measured in tens of miles. is coverage can be extended using a network of tall, high-power towers so that radio systems can be created to cover cities, states, and even whole nations. LMR systems are Figure 13. LMR architecture.

48 Transformation in Wireless Connectivity: Guide to Prepare Airports designed to provide quick and secure transmission in a robust spectrum of environments. They have an outstanding reputation for reliability based on the ruggedness of equipment, military- grade encryption of voice and data transmissions, and the numerous failsafe options built into LMR radios and networks. Graceful degradation mechanisms are built-in LMR features to guarantee communications reliability in situations of failing infrastructure. This is done by local fallback options and, in the case of P25, direct off-network communication. This feature, enabling group communications for first responders in non-coverage areas, is a major advantage over cellular communications for safety applications, although 5G is expected to support a similar feature in the next years. The limitations of LMR become clear when compared with its cellular alternative: the heavy weight of high-power transceivers, inefficient use of scarce radio spectrum vs. total network capacity available per channel, and a nationwide channel assignment. Low-bandwidth commu- nications, designed primarily for audio, support basic data applications, and PTT voice is a basic level of interaction between users for tactical communications. LMR provides good in-building coverage, however, unless repeaters are deployed, reception gaps are frequently experienced at certain indoor spots. In addition, many P25 features present interoperability challenges. Switching or interoperating from an LMR system is challenging. Except for a few P25 trunked systems, most LMR systems do not have IP back-ends. The lack of standardized operating proce- dures, training, and interjurisdictional coordination usually makes P25 network interoperability with IP systems, and even across agencies, difficult and limits the availability of spectrum. To solve the latter problem, several states are implementing statewide LMR networks with shared chan- nels to improve spectrum rationalization. However, first responders are equipped with both LMR and cellular radios due to this lack of integrated options, and evolution from LMR is not feasible in the short term. Because of this, LMR networks are likely to remain in the short-to- medium terms. 1.2.1.5 Low-Power Wide-Area Networks (LPWANs) in Unlicensed Spectrum For IoT applications, conventional cellular options consume too much power, and in many scenarios, they do not fit well with applications where only a small amount of data is transmitted infrequently. Moreover, many IoT scenarios do not fit with short-range wireless technologies such as Bluetooth or RFID/near-field communications (NFC). Instead, LPWAN technologies are suitable for IoT applications that can transmit small amounts of data over a long range (i.e., 5 km in urban zones to 40 km in rural zones) for a long period (e.g., 10+ years of battery lifetime) with exceptionally low cost (i.e., with a radio chipset costing less than $2 and an operating cost less than $1 per device per year). In addition to cellular LPWAN (see cellular technology), other technologies offer similar characteristics in the unlicensed frequency band (below 1 GHz). Among these, LoRa, Sigfox, and HaLow are gaining the strongest traction in the market, although there are others such as Weightless, Ingenu RPMA, and Symphony Link: • Sigfox is a proprietary technology, but it has built an ecosystem of vendors worldwide. Sigfox maximizes coverage for wide-area sensor networks and has building penetration for indoor deployments. Its narrow band allows for spectral efficiency, as each message uses minimal channel bandwidth, which improves overall system capacity and scalability. Its very low data rate translates into long transmission cycles and a higher probability of interference, making it less useful in unlicensed spectra crowded by coexisting systems. In addition, it does not support mobility, and its nodes must be stationary. • LoRa is maintained by the LoRa Alliance and is deployed in 157 countries. LoRa targets slightly higher data rates than Sigfox, and it also supports device mobility up to approximately

Taxonomy of Wireless Technologies and Their Uses in Airports 49   40 km/h. LoRa uses Spread Spectrum, which results in high bandwidth, thus potentially increasing collision probability in larger networks and aecting scalability. is issue can be overcome using dierent spreading factors and bandwidth combinations. However, it requires dedicated radio planning expertise. • HaLow follows a dierent approach to IoT. Preparing for the potential rise of sensing and tracking applications that require the exchange of high trac, HaLow is positioned as a hybrid IoT–wideband system. As a result, HaLow supports a shorter range (about 1 km) but with a higher capacity (about 10 Mbps). is technology is still in the early commercial stage, but it is intended to support wireless IoT use cases with higher throughput requirements. Like cellular options, unlicensed LPWAN connects IoT nodes in a star topology over large coverage areas through a WAN. Base stations or gateways collect data from sensors, which are routed through the network server via Ethernet, Wi-Fi, or cellular backhaul (Figure 14). e dierence is that in unlicensed LPWAN, the radio communications between the device and the gateway are broadcast, meaning that more than one gateway can receive the same data transmit- ted by a node. is makes the radio link much lighter, as there is no subscriber management, and device mobility does not cause network overhead. Data duplications and consolidations are managed by a dedicated server present in the backbone network, usually deployed in the cloud Once data are in the cloud, they are disseminated to the customer for processing and visualiza- tion, or to other computing and sharing resources in the WAN. Strengths and Limitations. Regarding strengths, all LPWAN options are a good com- promise of reliability and battery life and make appropriate choices for IoT applications that should be implemented in dense locations and/or require long-term monitoring where the large data rate is unnecessary. Such applications include sensors installed in cities or large buildings that need to send small data across a wide area over a long period. And it is more useful for a long-range capability than mesh networks, such as Zigbee, which are only useful within a short or medium distance. ese technologies are free from mobile operator technology, frequency license issue, and the cost associated with them. Specically, for LoRa, open standards for IoT device suppliers facilitate integration and additional developments such as mobile gateways or proximity-based services. Regarding potential limitations, because these technologies use unlicensed bands, they are more likely to be aected by interference. In addition, both Sigfox and LoRa are essentially based on proprietary technology, although LoRa supports open standards for applications and interfaces by IoT device manufacturers. LoRa’s chip manufacturing is proprietary to a single semiconductor company. Sigfox has a more vertical integration driven by a single company. Both cases may create a technology risk eventually, as they are not supported by global standards orga- nizations. In addition, Sigfox uses the company’s proprietary WAN for radio communications, Figure 14. Unlicensed spectrum LPWAN architecture. Dashed colored lines show the connections between an object and one or several concentrators/gateways.

50 Transformation in Wireless Connectivity: Guide to Prepare Airports which makes the technology unusable if the service area is not covered. HaLow overcomes these issues because it is designed as a fully open standard; however, a commercial ecosystem has not developed yet. Because unlicensed LPWAN coverage is not widely available like cellular operators, gateways are required to connect the end devices to the network. This will require maintenance of both the network and devices. Although this is adding an extra network infrastructure, the location of the gateways can be catered to the specific airport propagation environment to ensure cover- age to all devices. 1.2.1.6 Personal Area Networks (PANs) PANs are wireless networks created and maintained by neighboring communication devices. The standard for PAN is based on IEEE 802.15 but its evolution is maintained by two different trade groups and traditionally targets different applications—Bluetooth and Zigbee. Bluetooth is maintained by the Bluetooth Special Interest Group (SIG). The traditional use cases for Bluetooth have been personal devices such as audio and wearables, which require ranges up to 30 meters. However, the effective distance between Bluetooth devices can be greater than a kilometer. Bluetooth has evolved into two strains: on one side, basic rate/enhanced data rate (BR/EDR), specified by Bluetooth specifications 1.0 to 3.0, and, on the other side, BLE, which includes versions 4.x and 5.0. BLE uses a different radio technology than BR/EDR, but BLE devices are backward-compatible with BR/EDR. BLE has now become the default Bluetooth protocol version as the technology is pivoting to the IoT market. BLE is targeted to both consumer and IoT devices, offering a much longer range, high speed, low energy consumption, cheap costs, and connection- less services. In addition to the traditional point-to-point communication between connected devices, BLE supports additional topologies (Figure 15), including mesh for large-scale IoT networks and point-to-point device communications, which supports connectionless broadcast messaging with groups of devices. There are three BLE modes: • Low energy 1M. Legacy, small amounts of data (1 Mbps), used occasionally, range of 350 m with LOS. • Low energy 2M. Higher throughputs (2 Mbps), low power, lower range (up to 280 m with LOS). Figure 15. PAN architecture options.

Taxonomy of Wireless Technologies and Their Uses in Airports 51   • Low energy coded. Lower throughputs (125 or 500 kbps) but quadruple the range (up to 1 km with LOS). Zigbee is based on the IEEE 802.15.4 specification for PAN, promoted and certified by the Zigbee Alliance. Version 1.0 was released in 2005, and the current version is Zigbee Pro from 2007. The network stack Dotdot was released in 2017 and is the default application layer for Zigbee devices, adding native support to IP. Zigbee products work with every Zigbee-certified connected home or business platform using interoperable application profiles (e.g., Smart Energy), which tend to operate in a mesh topology. Zigbee products are backward-compatible with exist- ing Zigbee products and legacy profiles. They can connect and communicate with millions of Zigbee products already deployed in smart homes and buildings. Zigbee is typically used in low-data rate applications that require long battery life and secure networking, including smart building and industrial domains. It is best suited for intermittent low-latency data transmissions from a sensor or input device. There are many other PAN tech- nologies based on IEEE 802.15 specifications for specific verticals such as industrial process auto- mation (WirelessHART, ISA-100.11a) and smart homes (Z-Wave). Ultra-wideband (UWB) is another 802.15-based PAN family starting to gain commercial traction, focused on precision location in frequency-sensitive indoor environments, such as manufacturing and hospitals. Strengths and Limitations. A strength of PAN technologies is the mature market of manu- facturers offering chipsets and middleware/protocol development kits for the wider electronic industry. Both BLE and Zigbee can cover about 100 to 1,000 m for IoT applications in outdoor environments, and thanks to their mesh capability, devices can organize themselves in a distrib- uted communications platform that covers larger building spaces. Ubiquitous support of low-cost, low-power BLE transceivers in mobile devices, combined with their ability to support point-to-multipoint communications (beacons), and most recently, centimeter-level location accuracy with the introduction of Bluetooth 5.1, is enabling BLE to be increasingly leveraged between consumer devices and smart buildings for interactive applica- tions such as indoor location-based services or access control. Zigbee and BLE are both designed to be simpler to deploy and less expensive than Wi-Fi, but they can connect many more devices in a mesh network (65,000 Zigbee, 32,000 BLE). This volume capability and simplicity of planning and installation make PANs fully scalable technolo- gies. Targeted at battery-powered devices in wireless control and monitoring applications, one of the big advantages of Zigbee is low-latency communication. Its network join time is approxi- mately 30 ms, much faster than Wi-Fi (approximately 3 seconds) and Bluetooth (approximately 10 seconds). A limitation of PAN technologies is that they work well in simple applications where devices connect securely with minimal configuration but are not ideally suited for network access where high speeds or user management is required. The use of unlicensed bands makes these tech- nologies prone to interference. However, their protocols are specifically designed for robustness in crowded environments. The range is another limiting factor, especially for Zigbee (100 m). However, this can become a strength by contributing to robustness against interference. 1.2.1.7 Radio-Frequency Identification (RFID) RFID is a technology used for wireless readings of digital data encoded in identification tags. ISO/IEC 18000 describes an RFID technology, including air interface communication at dif- ferent frequencies. RFID communication takes the form of a tag (transponder)–reader link. Since its first patent in 1983, RFID has become widely used in the form of tags attached to all types of inventories (clothes, key fobs, electronic equipment, documents, or even live animals).

52 Transformation in Wireless Connectivity: Guide to Prepare Airports NFC protocols and data exchange formats are based on existing RFID standards as outlined in ISO/IEC 18092, and specic for 13.56 MHz RFID tags and contactless smart cards. NFC allow the same RFID device to act both as a reader and as a tag and is usually integrated within electronic devices such as smartphones. RFID supports dierent communication modes between interrogators and targets of identi- cation. ere are two types of target tags or devices (Figure 16): • Active tags contain a power source (self-powered or battery-assisted in the case of an NFC- capable device) and transmit a signal to an active or passive reader. e range can be up to 100 meters, except NFC use very low-power transmission to stay within 4 cm. • Passive tags receive power from an active transmitter, then send a signal back using a small portion of this energy. e range is usually within centimeters. Strengths and Limitations. Its main strength is that, by denition, RFID is the method of uniquely identifying items using radio waves. Electronic data collection with RFID avoids data transcription errors and avoids “missed items” when used to collect data on large numbers of items at once. is makes RFID appropriate for high-integrity applications of dierent security levels, such as inventory tracking, access control, or credit card payment. In addition, RFID and NFC are extremely cheap and energy-ecient and do not even require battery powering for pas- sive tags, which can then be installed on large volumes of assets. ISO/EIC standard maintenance, revised every 5 years, ensure interoperability between tags that are compliant and a thriving ecosystem of interoperable tag and reader components for a myriad of applications and markets. It can also provide room-level location accuracy without the need for any other communication infrastructure, although the accuracy increases with the number of readers (and thus with cost). In addition, RFID is very easy and exible to deploy, with no specialized labor or infrastruc- ture planning required. RFID is highly scalable, making extensions and modications of RFID infrastructure simple and cost-eective. Regarding limitations, compared to the barcode alternative, RFID is somewhat more expen- sive and complex (especially active tags), which makes it less cost-eective for disposable items (e.g., baggage tags, although IATA Resolution promotes its use). RFID has strict range limitations (although some active tags can reach 100 m) and low bandwidth, although this is a require- ment for secure applications. RFID performance is largely dependent on the environment. Figure 16. RFID/NFC communication modes.

Taxonomy of Wireless Technologies and Their Uses in Airports 53   For instance, reading accuracy decreases when working near metal objects due to RF signal reections. In general, the requirement of having tags attached to the object being tracked could, soon, make RFID less convenient and more expensive than emerging solutions based on com- puter vision for LOS environments (e.g., baggage tracking). 1.2.2 Technology Performance and Applications Each of the wireless technologies discussed in the previous section has strengths and weak- nesses that make it more appropriate for certain applications and services. is section provides an overview of how well technologies support dierent applications and services. Deploying, maintaining, upgrading, and repairing cables are both capital and labor-intensive. Consequently, wireline infrastructures constrain the number of connected users and their loca- tions. Wireless communications are needed when mobility, cost-eciency, exibility, and scal- ability are required. With recent advancements in the capacity, security, and reliability of wireless technologies, they can become comparable in some respects to wireline alternatives. However, performance is oen a tradeo that depends on technology selection and network design (including the amount of spectrum and coverage range). e comparison between maximum data capacity (throughput) and maximum range is largely technology-dependent and constitutes the most straightforward metric to compare wireless technology performance and suitability to applications. Figure 17 depicts this tradeo for the wireless technologies of study. Figure 17. Comparison of range and throughput among wireless technologies.

54 Transformation in Wireless Connectivity: Guide to Prepare Airports In addition to throughput and range, key metrics such as security, reliability, mobility, and device density determine the suitability of access technology to support specific applications or services. This section examines this aspect. Two broad application domains are defined sepa- rately, which address two different markets and applications: mobile user communications, auto- mation, and the IoT. Technology may support both types of applications. 1.2.2.1 Mobile User Communications Mobile user communications are services intended for the wireless transmission of payload information between users in the network. User devices are usually mobile but may be nomadic or fixed, and applications are usually conveyed visually to a human user. Consequently, the data throughput required by mobile communications may vary from light to very heavy. Figure 18 depicts the comparative performance of the wireless technologies in this category. Table 4 summarizes the suitability of wireless technologies for mobile user communication applications. The versatility of cellular technologies makes them capable of supporting virtually any use case, as they can be designed to maximize user data rate, device density, or reliability in a com- mon air interface. The same cellular infrastructure can be configured for all types of applications with dynamically varying needs and scales. Increasingly lower costs and vendor dependency and the upcoming availability of private cellular networks, make cellular technologies an equivalent, if not better-performing, solution to Wi-Fi for many applications. Cellular technologies provide better support for mobility, voice services, deterministic performance, and safety services. They also provide more advanced QoS and traffic management capabilities and can meet stricter SLAs. However, simplicity, cost-efficiency, and spectrum availability make Wi-Fi more attractive for enterprises and venue owners, most of whom already operate Wi-Fi networks for employees, tenants, and visitors. Wi-Fi is the preferred solution for enterprise-specific use cases (e.g., remote control or assistance, training, and customer services) and video-based applications (e.g., sur- veillance and analytics). In addition, the ecosystem of network components and devices for enterprises is enormous. Therefore, cellular technology is perceived as a complement to Wi-Fi to ensure coverage, increase capacity, or serve specific applications with more stringent requirements. Integration between both networks can provide significant benefits, such as: • Load balancing. Offloading traffic from a congested or coverage-degraded network increases service levels for users and optimizes spectrum use. This also allows network segmentation of services of different criticality. Throughput Coverage Low latency MobilityLocationaccuracy Battery life Scalability Wi-Fi Cellular LMR AeroMACS Reliability and security Figure 18. Comparison of technologies for mobile user communications.

Taxonomy of Wireless Technologies and Their Uses in Airports 55   • Subscriber management. Automatic, seamless Wi-Fi network discovery and signup for cel- lular users via roaming agreements greatly improve the customer experience for venue visitors and allows for better management of the subscriber. Different wireless technologies are also designed for specific physical environments. Wi-Fi targets high device density and capacity in small coverage cells and is optimized for indoor or campus-size coverage. WiGig takes this limitation to the extreme, providing very high capacity for extremely short distances, and is limited to use cases such as the proximity-based provision of heavy multimedia content, virtual reality, and haptic/tactile communications. In contrast, AeroMACS is specifically designed for reliable coverage of the entire airport surface, but it is specifically suited for outdoor applications. Cellular networks are, in principle, designed for wide-area coverage; however, coverage of indoor spaces with higher user density is also an option through the deploy- ment of small cells or DAS in venues. A relatively recent feature supported by wireless technologies is the high-accuracy location of mobile device users in an indoor environment. This capability enables proximity and location- based services such as wayfinding and proximity marketing, which provide high value for visitors and tenants in a venue. Bluetooth, and more specifically, BLE beacons, is the most accurate (cm-level) location technology. However, it usually has low utilization rates and requires a dedicated app running on the consumer side. In comparison, Wi-Fi provides an accuracy of tens of meters, which is only appropriate for proximity services. Cellular 5G shows promise in this domain, with the latest Release 16 targeting 3-m location accuracy, but it requires the deployment of mmWave small cells in the indoor space. Application Wi-Fi Public Cellular Private Cellular LMR AeroMACS Wireless HD screens & information kiosks Wireless self-service kiosk Mobile passenger checkpoint Contactless purchasing Mobile communications for visitors Enhanced in-building mobile carrier coverage Mobile AR wayfinding Wireless enterprise communications Airport staff radio communications Connectivity of electronic flight bag (EFB) Mobile AR for aircraft maintenance Wireless closed-circuit TV surveillance Virtual ramp/ground traffic control system (VRCS) Mobile AR surveillance Radio communications for first response teams Wireless real-time surveillance for incident investigation Table 4. Applicability of technologies for mobile user communications.

56 Transformation in Wireless Connectivity: Guide to Prepare Airports Security and reliability are key requirements for enterprise networks and mission-critical communications. Enterprise communications give secure access to staff for applications includ- ing intranet, resource sharing, teleconference, and collaborative decision-making, and require high capacity only achievable by cellular, Wi-Fi, or AeroMACS technologies. Because Wi-Fi makes use of an unlicensed spectrum, it does not provide the carrier-grade reliability that may be required for highly critical services. Tactical communications, or real-time exchange of critical data/voice information, paging, and radiolocation between agents in the field carrying portable radios, for day-to-day and inci- dent response operations, have traditionally been the domain of LMR. These systems have been operated by public-safety agencies (e.g., firefighting, ambulance, law enforcement, TSA/CBP) for critical communications, and by private entities for commercial use. Trunked infrastruc- ture LMR networks are usually operated by public-safety agencies or large venues that require tower or booster amplifiers for appropriate area coverage; smaller entities tend to rely on direct (off-network) communication mode. LMR operators, especially in trunked infrastructure, are licensed specific radio channels in their coverage area. For incident response collaboration, it is a regular practice that trunked infrastructure owners share access to certain “mutual aid” radio channels with other entities (e.g., local/county safety agencies with an airport, or vice versa). Cellular technology has become a contender in recent years to provide both mission-critical communications and wideband enterprise applications (including AR and mobile surveillance sites) for public-safety and commercial entities. In the United States, a nationwide public-private partnership called FirstNet has made 20 MHz of spectrum available for high-power cellular equip- ment. The FirstNet mandate is to provide a common cellular system across the nation for real- time, always-on, prioritized, encrypted first responder communication during multi-jurisdictional incidents. Spectrum fragmentation is a major LMR problem being addressed by several states inde- pendently. However, FirstNet has the ambition to solve the problem nationally, and a coexistence of both LMR and FirstNet is likely, with no clear winner in the longer term. Two major limitations of cellular technology for disaster recovery scenarios compared to LMR are: • Current cellular implementations like FirstNet do not offer graceful degradation including fallback and off-network communications, although 5G can incorporate direct communication (sidelink) features. • In-building coverage is not guaranteed even for high-power devices. Indoor cellular deploy- ments may be a solution for this, but there are no solutions for this at this time. AeroMACS is another option for reliable communications on an airport surface. It can com- pete with LMR for incident response applications and, like cellular, can support high-data-rate information feeds for high-volume planned-event and disaster scenarios, such as deployable cells on vehicles for mobile command centers and video streaming. However, AeroMACS is primarily focused on air operations within the airport perimeter, and this may reduce its appli- cability to inter-agency coordination scenarios. As a private airport infrastructure like Wi-Fi or private cellular networks, AeroMACS can give the wideband service access to different types of devices: • Aircraft integrated devices (avionics). Aircrew communications for ground operations and emergency coordination. • Fixed devices. Data backhaul for airfield sensors, radars, and lighting and surveillance func- tions such as perimeter surveillance, aircraft positioning, runway incursion prevention, and FOD. AeroMACS units provide access to multiple users behind the unit, either creating local Wi-Fi APs or accessed by Ethernet LAN. • Mobile devices. Communication with ground staff and vehicles, tracking of mobile assets, and coordination of apron operations. AeroMACS units are either vehicle-mounted or handheld and provide multi-band communications supporting also cellular, LMR, Wi-Fi, and/or bar- code readers.

Taxonomy of Wireless Technologies and Their Uses in Airports 57   Because AeroMACS is the only wireless technology standard certified for aviation safety on the airport surface, including flight deck communications, FAA supports it. FAA uses AeroMACS in eight U.S. airports as part of the FTI. FAA AeroMACS networks are not acces- sible to non-federal users. However, deployments co-located with FAA are possible where the airport, or a service provider, secures the frequency license to provide connectivity to the airport or its tenants. AeroMACS infrastructure is sufficiently flexible to be scaled up and reconfigured for different applications, including edge use cases such as parking management and IoT. 1.2.2.2 Automation and Internet of Things (IoT) Automation and IoT refer to networks of physical objects that can autonomously commu- nicate information about their status and surroundings, can actuate over physical assets, and can automate tasks such as industrial processes and transportation. IoT applications support strategic and tactical decision-making processes such as asset maintenance, automated control, and personnel safety. Table 5 summarizes the suitability of wireless technologies for automation and IoT applications. Application Wi-Fi Public Cellular Private Cellular AeroMACS PAN U- LPWAN RFID Wireless parking and electric vehicle charging Location-based visitor information Wireless-based passenger flow monitoring Wireless asset tracking, monitoring, and control Wireless advanced visual docking guidance systems Wireless cargo pallet tracking Wireless baggage tracking Wireless taxing guidance Wireless airfield sensors Wireless-based automated access control Wireless-based airfield vehicle & aircraft surveillance Autonomous surface vehicles Mobile robots Uncrewed aerial vehicles (UAVs) First responder personal protection Wireless-based social distance monitoring Wireless-based automatic passenger temperature screening Touchless travel Wireless-based staff contact tracing Wireless terminal sensing Table 5. Applicability of technologies for automation and IoT.

58 Transformation in Wireless Connectivity: Guide to Prepare Airports Throughput Coverage Low latency Mobility Reliability and… Location accuracy Battery life Scalability PAN U-LPWAN RFID Figure 19. Comparison of technologies specific to automation and IoT reliability and security. Pervasive wireless connectivity is a major driving force behind the IoT revolution and a fun- damental building block in its architecture. The use of connectivity is not just about getting a message to its destination; it is about doing so in a scalable, secure, and cost-effective fashion. In IoT deployments, it is typical to have multiple technologies operating in devices in the same area and frequency band, thus robustness is also critical. Figure 19 depicts the comparison of relevant aspects of wireless technologies in this category. Cellular technology is increasingly attractive to deploy machine communications and IoT. 5G introduces significant improvements by supporting two different usage scenarios for these applications: • Ultra-reliable low-latency communications (URLLC) specifically target use cases like moni- toring and control of connected vehicles and other mobile assets (e.g., robotics). • Massive machine-type communications (mMTC) target massive, high-density IoT networks of low-cost, battery-powered sensors working together (also called LPWAN). In the path to mMTC, LTE has been supporting two LPWAN protocols supporting km coverage range and years of device battery life for small-footprint, cheap sensor devices. Both have been used in industrial IoT applications in private network settings using licensed fre- quency bands. • NB-IoT is good for simple, low-power applications requiring a small amount of data trans- mission. It can only transmit data in a half-duplex mode and cannot support voice applica- tions, so it is intended to provide a specific set of data for massive sensor-type applications. It supports a longer range compared to eMTC/mMTC due to its narrow bandwidth. It is envisioned for stationary applications instead of mobile devices. Some applications where it has been successfully used is for metering applications such as parking, utility, environmental sensors, waste management, lighting, and tracking applications for retail. • eMTC/mMTC can provide a larger amount of data throughput compared to NB-IoT and includes Voice over Long-Term Evolution (VoLTE), which can enable additional applica- tions. Unlike NB-IoT, it can be used for mobile devices that do not require a significant amount of data, such as transportation tracking, asset tracking, and health/body monitoring. With the VoLTE feature enabled, it can also be used for emergency and security situations allowing for both data and voice to be transmitted from the network or device. It has been used in agriculture applications where various sensor systems are working together, such as irrigation, environmental monitoring, and high-cost asset tracking. Both eMTC/mMTC and NB-IoT are intended for massive, latency-tolerant sensors in indus- trial IoT, smart buildings, and smart city applications. The slightly different features allow

Taxonomy of Wireless Technologies and Their Uses in Airports 59   flexibility of design, and they can work together to allow for a range of data transmission mobility and battery life requirements. They can both operate in private enterprise environments, or leverage carrier cellular infrastructure. The latter guarantees reliable coverage; however, it comes at the cost of power efficiency due to frequent synchronizations with the network. Like carrier-based eMTC/mMTC and NB-IoT, unlicensed LPWAN like Sigfox and LoRa are intended for wide-range, low-data applications such as smart parking sensors, smart water meters, waste container control, and smart building (e.g., smoke detection, asset tracking, and room usage). Both LoRa and Sigfox have enabled geolocation functionalities with no dedicated cost for GPS hardware. Although Sigfox targets high scalability and reliable coverage for very low-data rate, stationary devices, LoRa is focused on mobile sensors and a slightly higher data capacity. Compared to its unlicensed counterparts, cellular LPWAN provides relatively higher peak data, which further increases power budget requirements. Available as managed connectivity services from mobile carriers, service availability depends on carrier network coverage. In gen- eral, cellular LPWAN options are most suitable for higher data rate IoT use cases in environments where mobile carrier infrastructure is mature. However, they are not optimal for applications where ultra-low power is a high priority, and for remote locations. Given the high energy requirements and limited range, Wi-Fi is a less feasible solution for large networks of battery-powered IoT sensors. Instead, it is more suitable for devices that can be easily connected to a power outlet like digital signs or security cameras. Interference is also a challenge in Wi-Fi, given that an increase in the number of end devices can quickly degrade connection quality. The novel Wi-Fi HaLow technology is intended for a wide range of IoT use cases with different needs in terms of data rate and range. Its main characteristic, inherited from Wi-Fi, is versatility, supporting a wide range of bandwidth values, coverages of up to 1 km, and Mbps data rates while maintaining a battery life of years. Consequently, HaLow could be configured to support large sensor networks for varying applications that include climate, building, goods, and healthcare monitoring and control. BLE is widely used in large-scale industrial IoT environments, smart buildings (thermo- stat, lighting control), and in-vehicle communication and control. Due to its ubiquity in con- sumer devices and its capability to support high-speed communications, Bluetooth is widely used for wireless control and content streaming of peripheral devices (e.g., headsets, smart- phones, GPS, and sensors). BLE-enabled devices such as sensors can be used in conjunction with electronic devices such as routers or smartphones that transfer data to an enterprise network. Unlike Wi-Fi, BLE applications are usually simple and allow two or more devices to connect with a minimal configuration like a button press. This makes BLE a good candidate for access control applications using consumer electronics (e.g., smartphones). A downside of BLE is that it uses the 2.4 GHz unlicensed spectrum which is prone to interference issues. However, the limited utilization range, for example, 10 to 50 m, becomes protective mitiga- tion against these issues. BLE networks are usually combinations of self-managed BLE mesh networks (e.g., beacons) with IoT applications, which also interoperate with user networks through consumer electronics, which are also connected to other wireless networks. BLE-based location capability with high accuracy makes it ideal for proximity and position-based services for public-owned consumer electronics and asset tracking. Consequently, it is a widely used solution to provide location services for indoor navigation and visitor analytics, and in factories and offices, though usually combined with Wi-Fi to expand the sample volume.

60 Transformation in Wireless Connectivity: Guide to Prepare Airports Zigbee use cases are focused on home automation, medical device data collection, and other low-power, low-bandwidth needs to be designed for small-scale projects using low-cost digital radios with low mobility. Some examples include smart city lighting, specialized utility solu- tions, embedded sensing, smoke and intruder warning, and smart building (connected lighting, building automation, remote configuration, efficient energy control, climate and HVAC control, daylight and window blind systems, room assignment and access control, and safety). In managed venues, Zigbee networks are usually managed by the enterprise as complements to Wi-Fi networks and are self-configurable in scalable mesh topologies. However, a mesh is not power-efficient and network management can become complex. Mesh solutions are best suited for medium-range applications where nodes are evenly distributed in the space. RFID use cases vary with the type of tag, which is related to the frequency range of operation, and consequently, to the read range and tag cost: • Low-frequency (30–300 kHz) tags have a maximum range of 10 cm and work well near liquids and metals, although the data rate is limited. Examples: Animal tracking, access control, and car key-fobs. • High-frequency (13.56 MHz) tags have a maximum range of 30 cm and have a low-data trans- mission rate and memory. Examples: Library books, personal ID cards, and NFC applications. • Ultra-high-frequency (300–3000 MHz) tags can be active or passive. – Active RFID tags have a maximum range of 100 m and show high memory and data trans- mission rates. However, they have a high price per tag (up to $50) and related software and suffer from high interference from metal and liquids. Examples: Vehicle tracking, manu- facturing, mining, construction, and asset tracking. – Passive RFID tags have a maximum range of 25 m and show medium memory capacity and data transmission rate. Examples: Supply chain tracking, manufacturing, pharmaceuticals, electronic tolling, inventory tracking, and asset tracking. RFID suppliers serve a high-volume market with the objective that every asset (e.g., sensor, display, inventory, and smartphone) can become uniquely identifiable by a tag to be read by a questioner. This includes RFID tags for asset management applications configurable by the user, specialized devices with embedded RFID/NFC tags such as credit cards, and NFC chipsets inte- grated into consumer electronics for user identification and payment. Because NFC devices must be close to each other, usually no more than a few centimeters, it has become a popular choice for secure communication between consumer devices such as smartphones. NFC enable simple and safe two-way (point-to-point) interactions between elec- tronic devices by typically bringing them within a few millimeters of each other. This unique ability has made NFC a popular choice for contactless payment. Also, NFC devices can read passive NFC tags, and some NFC devices can read passive HF RFID tags that are compliant with ISO 15693. The data on these tags can contain advertisements, signs, or commands for the device such as opening a specific mobile application. For travel, NFC are widely used in passport reading. It has been a promise for years as embedded in airline boarding passes, but this use case has never been widely deployed. 1.2.3 Spectrum Usage To provide a common reference to analyze available choices of frequency bands and study interference risk, this section discusses the use of the frequency spectrum by different wireless technologies. Frequency bands have varying characteristics that can make them either more or less suitable for different applications. Table 6 summarizes the most relevant characteristics of different frequency bands used by wireless technologies.

Taxonomy of Wireless Technologies and Their Uses in Airports 61   Table 7 shows the spectrum bands usable by the analyzed wireless technologies in the United States. According to utilization rules and license requirements, there are three major types of spectra: • Licensed. Most of the radio spectrum is licensed by the Federal Communications Commis- sion (FCC), or an FAA-assigned frequency manager in the case of AeroMACS, to certain users such as mobile carriers or public-safety agencies. Individual companies pay a licensing fee for the exclusive right to transmit on an assigned frequency within a certain geographical area. In exchange, those users can be assured that nothing will interfere with their transmission. • Unlicensed. In an unlicensed radio spectrum, any user is free to transmit. However, manag- ing interference between adjacent users is more difficult in an unlicensed than licensed spec- trum. This can be done by wireless network planning, and/or by control of users authorized to transmit in the space. • Shared. A shared radio spectrum allows for unlicensed access to users under the condition that they respect coordinated sharing mechanisms to protect incumbents in the same band. Frequency band Characteristics >24 GHz (mmWave) Very short ranges, very high capacity. Appropriate for very dense indoor environments. 1–6 GHz Compromise between capacity and range. Used for indoor and campus environments. Unlicensed ISM bands 2.4 and 5 GHz are crowded in dense environments. New frequencies in 3.5 GHz and 6 GHz allow new, non-crowded bands for unlicensed and shared spectrum. <1 GHz Best for long-range connectivity and penetration through walls. Energy-efficient, thus more appropriate for low- power IoT. Table 6. Summary of frequency band characteristics. Technologies 0–300 MHz (VLF/ LF/MF/HF/VHF) 300 MHz–3 GHz (UHF) 3–30 GHz (SHF) 30–300 GHz (EHF) Cellular (5G 4G LTE CAT1+) 600, 700, 750 (FirstNet), 800, 850, 1900, 1700/2100 (AWS), 2300 (WCS), 2500, 2600 MHza 3100–3550 MHzd 3550–3750 MHz (CBRS)c 3750–4200 MHz (5G)d 5150–5835b 5925–7125 MHzc 24 GHz, 28 GHz (5G)a 39 GHz (5G)a 60 GHz (5G)d Wi-Fi 2400–2483 MHzb 902–928 MHz (HaLow)b 5150–5835 MHzb 5925–7125 MHz (Wi-Fi 6E)c 57–70 GHz (WiGig)b AeroMACS 5000–5030 MHza 5091–5150 MHza LoRaWAN Sigfox 915 MHzb Bluetooth BLE 2402–2480 MHzb Zigbee 915 MHz, 2402–2480 MHzb RFID NFC 125–135 kHzb 13.56 MHzb 868–930 MHz, 2.45 GHzb 5.8 GHzb P25 TETRA 30–50 MHz, 150–172 MHza 450–512 MHz, 700–900 MHza Notes: aLicensed bUnlicensed cShared (tiered) dExpected future Table 7. Spectrum usage by wireless technologies in the United States.

62 Transformation in Wireless Connectivity: Guide to Prepare Airports This type is being applied to frequency bands recently opened to a wider range of users: 3.5 GHz (CBRS) and 6 GHz. Some frequency bands are under assignment and are expected to be released soon. Cellular technologies can use a wide selection of frequency bands in the licensed spectrum, whose availability in the United States depends on FCC regulation and spectrum license auctions. Mobile carriers have secured exclusive licenses for these frequency bands. Certain devices like a passenger’s phone may be locked to a specific carrier and only operate on that car- rier’s specific bands. A mobile carrier with a frequency band license can cover very wide cover- age areas and ensure the quality of service for its traffic in a deterministic way within the band, without risk of interference. With the evolution of wireless access technologies, cellular networks increasingly use higher frequencies, which have more limited reach, but typically wider channels, thus increasing the overall capacity of cellular networks. Higher frequencies are particularly well suited for use inside buildings and in dense networks, where there is a high concentration of traffic. With 4G, operators have started to deploy in sub-3-GHz and sub-6-GHz bands. 4G includes eMTC and NB-IoT devices, which operate on the same licensed frequency bands, as these devices require cellular network coverage from a mobile operator. For public-safety applications, the U.S. government has made 20 MHz of spectrum available at 700 MHz in Band 14, managed by the FirstNet authority. 5G is a major change: Although most of the deployments worldwide are in the mid-band (2.5–3.7 GHz), it can also be deployed in low-frequency bands (and use spectrum previously used by 2G and 3G) and in the mmWave bands. In the United States, the limited availability of mid-band spectrum has encouraged operators to use mmWave spectrum more intensely than in other countries. Because most cellular frequency licenses are assigned to mobile carriers, enterprises and venue owners usually can only be subscribers of the operators (e.g., for 5G LPWAN sensor networks) or let the operators directly provide the service to consumers (e.g., mobile passenger communica- tions). Both scenarios have the risk associated with the lack of control of the spectrum. Venue owners find it difficult to use these bands to support their services and applications. They can do so if they have agreements in place with the mobile operators with the spectrum licenses, enabling carrier-operated private networks. Venue managers can also install small cells or DAS, typically used as an extension of carrier networks, with the traffic and services managed by the mobile carrier. Another technology that uses a licensed spectrum is AeroMACS. FCC issued a Notice of Proposed Rulemaking (NPRM), pending publication, confirming AeroMACS operators have the priority of use in the 5000 to 5030 and 5091 to 5150 MHz for both FAA and non-federal users, including priority over other aviation telemetry and satellite communication systems. This license will be administered by a nationwide spectrum manager on behalf of the FAA to be assigned in 2022. This centralized approach is intended to ensure fairness, secure spectrum protection, and improve the governance of channels. For LMR, licensed entities are required to use spectrum as allocated by FCC to the organiza- tion over a limited geographic scope. This is usually the 800-MHz band and, for older networks, the 450-MHz band. Because the agencies lack interoperability, frequency channels are not opti- mally allocated or shared across agencies, which greatly limits the availability of the spectrum. Congress mandated improvements to public-safety communications in 2012 (2012 Public Safety Spectrum and Wireless Innovation Act), and several states are consolidating the channels for shared use across the state.

Taxonomy of Wireless Technologies and Their Uses in Airports 63   Unlicensed spectrum is open for use to any user if they comply with FCC power limitations for the specific band. Networks in unlicensed frequencies use a Listen-Before-Talk mecha- nism to select channels previously measured to ensure no interference with other networks. Equipment operating in the unlicensed spectrum is mostly easy and quick to deploy. On the downside, because it is open, any other entity in the vicinity can use the same frequency and cause interference. Wireless cells tend to have a limited range, and it is difficult to provide wide-scale coverage. The Industrial, Scientific, and Medical (ISM) bands, defined by the International Telecom- munication Union with the region and nation specifics, were originally designed for non- telecommunication RF applications but are now commonly used by wireless LAN and PAN Wi-Fi (2.4 GHz and 5.8 GHz) and Bluetooth (2.4 GHz). These portions of the spectrum are now considerably crowded, especially in dense population environments. The opening of the 6-GHz band (5.925–7.125 GHz) to unlicensed access in April 2020 promises to be a major change for Wi-Fi (so-called Wi-Fi 6E). Because the band is mostly unused and there is no overhead to manage legacy devices, channel throughput performance will be better and congestion interfer- ence will be lower than in the 2.4-GHz and 5-GHz bands. But most significantly, it is an unprec- edented allocation of new spectrum for unlicensed use. The new spectrum band has almost twice as much bandwidth as the combined 2.4-GHz and 5.8-GHz bands that Wi-Fi uses today. Wi-Fi 6E will increase the capacity of Wi-Fi, and some enterprises may need Wi-Fi 6E simply to address congestion in the ISM bands, where traffic levels continue to rise. Another popular unlicensed frequency band is 915 MHz, used by HaLow, Zigbee, Sigfox, and LoRa, and for UAV command and control. This band has ideal characteristics for long- range IoT communications and suffers little interference due to the short message size used by these technologies, which reduces the probability of conflict. However, there have been cases reported of technologies in this band having interference with public-safety radio transmissions in the band. Spectrum-sharing mechanisms intend to combine the freedom of unlicensed access with the guarantees of licensed access, in a technology-neutral framework that can be shared by multiple technologies at each location. Mandatory mechanisms are imposed on band users to ensure coordinated sharing, such as power limitations, contention control protocols, and mobility restrictions. This is the case for the 6-GHz spectrum, where FCC is defining the sharing rules based on Automated Frequency Coordination (AFC) mechanisms. AFC mechanisms are pro- cesses to request daily allocation of channels to an AFC coordinator within a geographical scope. A different shared spectrum scheme is defined for the CBRS, allocated in mid-band frequencies (3.5–3.7 GHz). A spectrum manager known as the CBRS Spectrum Access System (CBRS SAS) mediates access to spectrum by licensees in three priorities: • Incumbent users like federal users and fixed satellite services are protected against harmful interference from priority access licensees and General Authorized Access (GAA) users. • Priority access license (PAL) users have licensed a 10-year renewable 10 MHz portion through competitive bidding on a county-by-county basis (up to seven per county). PAL users have reliable access to their allocated channels, except for exclusion zones where the use of the 3.5-GHz band is reserved for incumbents. • GAA users share the remaining spectrum using mechanisms for fair coexistence. Using GAA is like using an unlicensed spectrum, with the additional constraint to avoid transmission in PAL and incumbent bands. PAL users mostly will drive deployments of public and safety-critical networks, while GAA will encourage the deployment of private networks in the enterprise. Although this authorization

64 Transformation in Wireless Connectivity: Guide to Prepare Airports framework implies additional complexity, CBRS offers an alternative to footprint-wide macro-cell networks and supports sustainable, scalable business models for indoor small-cell deployments funded and owned by enterprises and venue owners, which have so far eluded the U.S. market. Federal agencies operate wireless systems across the nation for governmental and National Security purposes. The U.S. government, and especially FAA, operates myriad systems for com- munications, navigation, and surveillance (CNS) supporting the safe management of the National Airspace. Many of these CNS systems are deployed in airports, mainly to support take- off and landing operations (Table 8). Ensuring non-interference with these systems is critical for stakeholders operating wireless systems in the airport domain. Thus, appropriate frequency planning and restrictions need to be applied when designing and operating the system. At the time of the writing of this report, the issue of 5G C-band interference with radio altimeters was at the center of a discussion involving FAA and FCC regulators, airlines, and avionics manufacturers. This has led to FAA regulations prohibiting takeoff and landing operations in low visibility conditions for some airframe types if 5G coverage is present. After several delays in rolling out 5G ser- vice in this band, involved mobile carriers have accepted a further postponement of turning on 5G service near airports, and FAA has defined “exclusion zones” to avoid reception of this type of cellular signal in high-risk airport runways. As this matter is mainly in the hand of regulators, airlines, and the telecommuni- cation and avionics industries, airport operators do not have much influence on this other than taking positions on strict safety regulations versus high-capacity 5G service in airport premises. Regulators and industry are working to determine whether there is a safety hazard and to set up protections if needed. However, airports must anticipate the potential outcomes of this issue, which may lead to the following scenarios: • No impact on the 5G coverage on airport premises. • Imposing restrictions on power levels, tower locations, or antenna directions, or prohibiting the usage of C-band in airport premises. It is important to note that 5G would still be provided, although in other bands that do not have as much available bandwidth. This would lead to a degraded 5G service in airport premises, in the form of reduced capacity. In airports having 5G capacity constraints, some alternatives for offering high- capacity wireless service to passengers and tenants in the terminal could be DAS (only 4G is mature, but mmWave could be used in the future) or Wi-Fi (including an OpenRoaming agreement for seamless handover of mobile services when in the terminal). For airport operations and safety, private cellular networks (including 5G) can be deployed, instead of using a mobile carrier, as they are intended for use in a different frequency (CBRS or 6-GHZ) that is not affected by this issue. AeroMACS, with a protected aviation spectrum, is also an alternative. For sensors and maintenance applications, cellular IoT is not really impacted by this issue. IoT devices have lower bandwidth requirements; thus, they are better suited for lower frequency bands. Other wireless sensor technologies working in the ISM or lower bands are also not affected.

Taxonomy of Wireless Technologies and Their Uses in Airports 65   CNS system Description Spectrum Potentially affected technology Narrowband FM Analog radio systems before LMR but still in operation in some environments for local police, fire, and emergency medical services. 0.3–3.4 kHz Non-directional beacon (NDB) Radio navigation aid used by aircraft to help obtain a fix of their geographic location, commonly used as “locators” in the instrument landing system (ILS) approach. 190–535 kHz RFID VHF omnidirectional range (VOR) Short-range radio navigation aid for aircraft, under decommissioning in the transition to performance-based navigation. FAA plans to retain a Minimum Operational Network (MON) supporting MON airports at suitable destinations within 100 nautical miles of any location within CONUS. 108–107.95 MHz ILS and local area augmentation system (LAAS) Provides an approach path for the exact alignment and descent of an aircraft on the final approach to a runway. 108.1–111.95 MHz VHF for aviation ATC, emergency search and rescue, FSS, EFAS, airport utility, UNICOM (uncontrolled airport), flight test, AWOS. 118–136.975 MHz Maritime VHF Communication systems for maritime safety operations at airports near water. 156–174 MHz LMR Distance measuring equipment (DME) Radio navigation aid that measures the distance between an aircraft and a ground station. Terminal transponders (often installed at an airport) typically provide service to a minimum height above ground of 12,000 feet. 960–1215 MHz Aircraft transponder Position signal broadcasted by GPS-equipped aircraft to allow ground surveillance through ADS-B or multilateration. 978 MHz, 1090 MHz Global positioning system (GPS) Satellite-based positioning system widely used on electronic devices and aircraft. 1227 MHz, 1575 MHz Airport surveillance radar (ASR) Surveillance system to detect aircraft approaching and departing busy airports, supports TRACON. 1.03–1.09 GHz, 2.7–2.9 GHz Radar altimeter Aircraft-equipped radar measuring clearance height over terrain or obstacles on takeoff and landing. 4.2–4.4 GHz A recent RTCA report estimates that contiguous 5G base stations in the C-band (3.75–4.2 GHz) could cause harmful interference, which can lead to catastrophic safety hazards (see text box). Cellular (5G) AMS(R)S Access to remote sites without sufficient (or cost-effective) wireline infrastructure 5.00–5.01 GHz AeroMACS FAA AeroMACS Provision of services on existing infrastructure. Envisioned supporting MAN-like services in a localized environment. Typically used for a distributed system within a metropolitan area that requires local IP services across a campus-like environment. 5.00–5.03 GHz and 5.091–5.15 GHz AeroMACS (airport-operated) UAV command and control Command-and-control functions for uncrewed aerial vehicles (UAVs) flying in controlled airspace. 5.03–5.09 GHz AeroMACS FAA microwave Access to remote sites without sufficient (or cost-effective) wireline infrastructure. New terrestrial microwave network that will provide assured communications services in areas where it is difficult or nearly impossible to use traditional telecommunications lines. 7 GHz, 8 GHz, and 15 GHz Surface movement radar (SMR) Radar used to detect aircraft and vehicles on the surface of an airport. 9 GHz, 15–17 GHz Table 8. CNS systems at airports.

66 Transformation in Wireless Connectivity: Guide to Prepare Airports 1.2.4 Deployment Models Enterprises and venue managers such as airports, which have control over the real estate where they operate, have different options for deploying and managing wireless technology on the premises. This section discusses three models for the deployment and operation of wireless technologies (Figure 20): • Public network. A mobile operator or other service provider operates the wireless network to provide access to its subscribers. • Neutral-host network. A delegated entity deploys and runs the network on behalf of the airport. • Private network. The airport pays for, installs, manages, and runs the network. Hybrid models are also possible, for example, mobile operators or neutral hosts deploying and running a private network for the exclusive use of venue manager services. Public Network Public networks are intended for a wide-area footprint and serve the subscribers of the ser- vice providers. The primary examples are mobile carriers (cellular, including cellular LPWAN for IoT) and public-safety (LMR) networks. The mobile operator funds, deploys, and operates the network and, in most cases, uses a licensed spectrum. The operator guarantees coverage, performance, and maintenance. Mobile carriers secure spectrum licenses and plan for coverage according to their business goals. Venue managers can facilitate appropriate coverage within their premises, including in the building, via arrangements with the operator. These are usually real-estate and connectivity agreements for tower sites and small cells, or via a neutral-host-operated DAS. In DAS, the mobile carrier is responsible for delivering the signal source to the building, while the neutral host is responsible for the DAS infrastructure and delivery to the end user. Mobile carriers can also dedicate specific channels to the venue manager or tenants to operate their private network. DAS are considered a cost-effective option for large venue surfaces, as cellular indoor coverage is usually a concern due to signal degradation. Small surfaces do not have this requirement, and the investment scale of DAS is not proportional. Figure 20. Wireless deployment models.

Taxonomy of Wireless Technologies and Their Uses in Airports 67   In addition to consumer applications, public networks can support public-safety services. Operator entities, being mobile carriers or public-safety organizations, distribute channel assign- ments among agencies in the coverage area and include some shared channels for mutual aid. Venue managers can then operate licensed channels or contract public-safety agencies for incident management and response on their premises. Public networks have the advantage of eliminating capital expenditures, and usually allow cheaper access to end-user devices due to economies of scale. On the downside, operational expenditures (OPEX) depend on service agreements with the operator, and a lack of control over network capacity and reliability can become a problem, because events in the covered venue (e.g., blockage, planned downtime, and construction) may create network outages or degradations out of the control of the customer. In addition, technology cycles are controlled by the operator, forcing customers into upgrades and/or causing disruptions in the service. Neutral Host Enterprises or venue owners may select an entity called a neutral host to own, deploy, and run the enterprise network. Most neutral-host networks today are used for the extension of mobile carrier public networks in indoor spaces for visitors, obtaining the source signal in a licensed spectrum from the operator, and distributing it via DAS to mobile subscribers. Neutral hosts fund DAS by charging a regular fee to the participating mobile carriers for running this RAN expansion on their behalf, and the airport improves indoor cellular connectivity at a very low cost. Roaming relationships with service providers are managed by the neutral host. Neutral hosts are now starting to expand their offerings and operate private networks in the unlicensed or shared spectrum for enterprises, venue owners, tenants, and visitors. This model targets network convergence by making the access technology and spectrum band agnostic to different types of users (Figure 21). There are multiple agreement options between the venue manager and the neutral host. Financial contributions for capital and operating expenses, revenue share, and operator exclusivity are negotiated between both parties. For instance, a venue manager may prefer to avoid investment in the network in exchange for the neutral host taking revenue and profits from network services. Other venues may choose a joint investment and revenue-sharing agreement. The benefits of a neutral host are network optimization, such as consolidated wireless planning, and load balancing. This model accelerates network densification and allows venue managers Figure 21. Neutral host operating DAS shared between mobile carriers and private cellular networks.

68 Transformation in Wireless Connectivity: Guide to Prepare Airports to reduce the costs of deployment and operation. A main limitation of the model is the com- plexity of agreements required for the customer to ensure the performance of the system, upgrades, and enhancements. Another limitation is that mobile carriers invited to provide service in a neutral-host network may face heavy fees or mark-up costs, which can slow down the adoption of this model. Private Network Private networks are built for a specific enterprise environment, where the enterprise has control over the users, applications, and access policies to the network. Most Wi-Fi networks today, PAN, and unlicensed LPWAN are operated as private networks. Airports sometimes operate private LMR systems on airport-licensed channels for tactical communications between airport staff. AeroMACS is expected to become a private network technology also for wideband safety applications. In the United States, there will be a growth of cellular pri- vate networks, especially for low-latency, highly reliable, and secure services. This is mainly driven by the expansion of the cellular spectrum in unlicensed and shared bands (6-GHz, mid-band CBRS). Venue managers may choose to operate private networks in the same way they manage struc- tured cabling, network equipment, or security. In this case, the venue manager has control over the network performance, timing, and funding, in addition to the responsibility to con- nect to the backbone infrastructure for internet access. The venue manager can share access with venue tenants and visitors according to configured access policies, for which appropriate service agreements need to be established. This option is usually more appealing to large orga- nizations with a strong IT or telecommunications internal group, and for safety-critical applica- tions like incident response or flight deck communications. In many cases, the actual operation of the network is outsourced to an IT supplier. The venue manager is responsible for obtaining spectrum use licenses or taking the appropriate interference mitigation measures if using unli- censed bands. Another option is to have a neutral host that owns, deploys, and operates the private networks in the venue. This is usually an option for venues that target network convergence and intend to commit limited financial and technical resources to the operation of the network. In this case, the neutral host has all the functions and responsibilities outlined above. In addition, neutral hosts can share the radio access infrastructure used for private networks with mobile operators via DAS. Mobile carriers can also provide private networks in venues using a dedicated portion of the licensed spectrum. In this case, the carrier owns, funds, and operates the infrastructure and charges the customer (the venue manager or a tenant) for connectivity and services. This option is best for venues that do not want to commit financial and technical resources to the operation of the network. 1.3 Operational Concept of the Wireless-Connected Airport This section describes the overall concept of operations for wireless technology usage in air- ports. A discussion follows on the actors involved and the relationship between them (“who”) and the wireless deployment architectures that can provide these capabilities (“how”). These aspects build a framework for airport operators to guide investment decision-making according to their characteristics and priorities.

Taxonomy of Wireless Technologies and Their Uses in Airports 69   1.3.1 Actors Involved in the Provision and Consumption of Wireless Services in the Airport As with any other service, wireless connectivity is defined by the relationship between the provider (supplier) and the consumer (customer) of wireless service. This relationship is defined in terms of the technical provisions and contractual agreements in place to govern the service. Figure 22 shows the actors involved in wireless connectivity services at an airport and the pos- sible relationship models available. The different relationship options depend on the deployment architecture implemented, which is described in detail in the next section. 1.3.1.1 Service Consumers (End Users) Wireless end users are the users of devices running a software application requiring informa- tion sharing over wireless media. This also includes machines that communicate automatically with the network (e.g., sensors, cameras, control devices, and wearables). There are three types of end users from the perspective of the service provider, as shown in Table 9. End users do not always require a service provider to support wireless connectivity unless access to a backbone network is required for internet connectivity. In some cases, they can operate in distributed networks fully deployed and operated by the end users, without the involvement of a third-party service provider. This is done in direct tactical communications for the staff or first responders, mesh sensor networks, or personal hotspots. Figure 22. Relationship options for wireless connectivity among airport stakeholders.

70 Transformation in Wireless Connectivity: Guide to Prepare Airports 1.3.1.2 Service Providers Wireless service providers are entities responsible for wireless connectivity. The service pro- vider can engage in the provision of wireless connectivity services at three different levels: • Own. It owns the network infrastructure, funds the equipment purchase and installation, and decides which technologies to deploy and upgrade. • Plan. It performs the network design and planning, decides the performance levels to offer, including cybersecurity planning, and is responsible for building, testing, and activating the network. It may be contractually liable in the form of SLAs. • Operate. It runs the network and subscribers, monitors its performance, provides visibility in the form of key performance indicators (KPIs), and is responsible for maintenance and repair including cybersecurity issues. It is contractually liable in the form of SLAs. Service providers can perform one or several of these functional roles in a non-exclusive manner. They can also perform a function only to a certain extent, for example, operating the network subscribers but not the connectivity. Internet service providers (ISPs) are WAN providers that supply the backbone infrastructure for global internet access. ISPs may operate a fiber backbone network or microwave link to the premises or may be mobile carriers covering the facilities. Airport operators may have a role in facilitating backbone connectivity to the premises through commercial agreements or political influence, but they do not usually fund the infrastructure. Connectivity is provided by ISPs to subscribers, which may include: • The airport operator or delegated entity, sometimes exclusively, for internet access from the premises. Mobile carriers can provide a dedicated private network to the airport operator. • Tenants, when they are directly responsible for internet connectivity access. • End users directly, when mobile carriers provide service to their subscribers in an airport facility directly or via DAS. Airport operators can manage wireless network infrastructure, either directly or via del- egated entities, to provide enterprise/consumer private networks or critical private networks dedicated to airport operations. Airport operators or delegated entities can also manage private networks provided by mobile carriers. The role of the airport operator in the provision of wireless services (i.e., whether it owns, plans, and/or runs the network) depends on the level of engagement desired. Airports can be broadly categorized according to three levels of engagement: • In a provider role, airport operators are responsible for providing connectivity to their guests and tenants. This includes building and planning the network infrastructure, even if the task Wireless end user Can access wireless service via Airport operator staff Public mobile carrier network Private network offered by a mobile carrier to the airport operator Private airport enterprise network Private airport critical network Tenant staff Public mobile carrier network Private network offered by a mobile carrier to the tenant or the airport operator Private airport/tenant enterprise network Passengers and other visitors or staff using personal devices Public mobile carrier network Private airport/tenant consumer network (limited to guest services) Table 9. Wireless end users.

Taxonomy of Wireless Technologies and Their Uses in Airports 71   is outsourced to a delegated entity, if the ownership and liability of the network infrastruc- ture fall within the purview of the airport operator. The connectivity and quality of service required by tenants also fall under the contractual responsibility of the airport operator as included in terms of lease or tenant service agreements. The day-to-day network operation may be outsourced to a delegated entity under the supervision and responsibility of the air- port operator. This is the case for airport operators that aim to rationalize infrastructure, have high-level technical resources to operate it, and can afford the financial investment. In this model, airport operators support the costs of the network and are responsible for technology upgrades and engineering cycles, but also receive all the value from wireless services in their facilities. • In a facilitator role, airport operators may be owners of the network infrastructure and/or responsible for planning the network coverage and performance but are not responsible for operating the network. Instead, a delegated entity (e.g., an IT operator or a neutral host) is responsible for running and maintaining the network and the quality of service for the airport staff and tenants. Typically, formulas of collaboration are established between the airport operator and the delegated entity. Examples of this are revenue-sharing agreements and centralized procurement processes at the airport to achieve purchase discounts or shared subscriptions for data or higher-priority services. In this case, the airport operator acts as a facilitator to support passenger satisfaction and tenant objectives and translates them into technical requirements for the delegated entity. Airport operators in this scenario do not need to have a large IT department managing network infrastructure, but rather drive innovation and strategy. In this scenario, airport operator staff may become users of the wireless network under special service agreements with the delegated entity. • In a “hands-off” role, airport operators are not involved in the provision of wireless con- nectivity. Instead, they rely on a mobile carrier or a delegated entity that owns, plans, and runs the networks. Tenants and visitors connect directly to the available networks without direct involvement by or contractual responsibility of the airport operator. This may require agreements between the airport operator and the ISP, mobile carrier, or delegated entity in the form of exclusivity contracts, financial support, or limited cost and revenue-sharing formulas. The airport operator’s role is limited to ensuring space and power via easement and utility provisions. It supports none or a few of the costs of deployment and operation and receives no direct revenue but can still benefit from non-monetary value generation. Also, because airports cannot regulate the use of spectrum by their tenants, cooperative arrangements are established to mitigate disruptive interference, as explored in ACRP Report 127. In this sce- nario, airport operator staff may become users of the wireless network under special service agreements with the ISP, mobile carrier, or delegated entity. Table 10 depicts the different levels of engagement and the associated roles of the airport operator. Tenants, in addition to operating the end-user devices for tenant-related activity, can be pro- viders of managed wireless networks for enterprise and customer applications. This can happen when tenants offer sophisticated services not supported by the airport network, or they prefer to have their own network for security or commercial reasons. In this case, the internet access required by the tenant network is provided by the following: • An ISP available in the facilities and usually requiring an agreement by the airport operator to install wire infrastructure and power through easement and utility provisions. • A mobile carrier offering a dedicated private network for enterprise applications. • A private network, provided by the airport operator or a delegated entity, offers access to an ISP through its integrated communication infrastructure as a service. This can be bundled into comprehensive service offerings together with rental and utility services as a tenant ser- vices agreement.

72 Transformation in Wireless Connectivity: Guide to Prepare Airports 1.3.2 Wireless Deployment Architectures in Airports This section describes the implementation models for the wireless network connectivity services which provide value from suppliers to consumers within an application environment. A deployment architecture is a logical definition of a network topology in terms of which users are connected and how. This, in turn, determines what use cases can be serviced, and what sup- porting technologies can be deployed. Figure 23 depicts the four deployment architecture models identified. They can be split into sub-models for specific use cases and business relationships. Note that an airport operator will commonly follow a combination of deployment architectures running simultaneously in the same environment to provide wireless services for different users and applications with varying performance requirements. 1.3.2.1 Public Network Infrastructure This architecture relies on a WAN mobile operator for the provision of both wireless connec- tivity to the end user and global access/internet access through the operator’s backbone infra- structure (Figure 24). Each airport may have multiple mobile operators providing coverage in the area. End users in this architecture are ultimately serviced by the mobile operator, either directly as subscribers, or in the case of cellular networks, via a neutral host. Management of the network and the spectrum is assured by the mobile operator. The mobile carrier, in most cases, operates in an exclusively licensed spectrum, which sup- ports the provision of reliable services. It is possible, however, that the operator could use an unlicensed or shared spectrum. This is the case for LTE-U and 5G NR-U specifications and unlicensed LPWAN (Sigfox) networks. There are four sub-models of this deployment architecture: • Using direct radio access to a mobile carrier, end users are cellular subscribers of the mobile carrier (e.g., passengers carrying their subscriber smartphones). This architecture has value in Level of engagement Recommended if the airport operator/sponsor Deployment models Provider Intends to be a service and infrastructure integrator. Has resources to fund, plan and operate the network. Intends to acquire the contractual responsibility for the provision of wireless services. Intends to centralize the generation of value. Can delegate planning and operation of specific wireless networks to other entities. Private network owned by airport operator (operation may be outsourced). Public network service. Facilitator Intends to share costs, risks, and value of wireless networks with service providers. Can direct the strategy of service provision and performance and translate it into requirements. Is in a position to facilitate the generation of value of wireless services for stakeholders. Agrees on cost and revenue-sharing formulas with service providers. Private network owned by airport operator (operation may be outsourced). Private networks provided by neutral hosts. Public network service. Mobile carrier service provided by neutral-host DAS. Hands-off Does not intend to acquire responsibility over the provision of wireless services. Is willing to give up control of the wireless network to a third party. Intends to minimize its costs but does not expect to generate relevant revenue from wireless. Neutral host-owned infrastructure. Private networks provided by neutral hosts or tenants. Public network service. Private network provided by a mobile carrier. Mobile carrier service provided by neutral-host DAS. Table 10. Levels of engagement of an airport operator in the provision of wireless connectivity.

Taxonomy of Wireless Technologies and Their Uses in Airports 73   Figure 23. Deployment architectures for wireless services at the airport. Figure 24. Public mobile network.

74 Transformation in Wireless Connectivity: Guide to Prepare Airports providing customer experience through ubiquitous connectivity on the premises. However, the service and subscriber are controlled by the mobile carrier without any involvement of the airport operator. Through roaming agreements, it is possible to hand over the subscriber to the airport’s private network, enabling the possibility to manage the subscriber. The airport environment is covered by cellular towers owned by the operator, although in some cases the airport operator negotiates the placement of additional towers in or near the property to improve cellular coverage. This is especially the case for small cells cover- ing indoor spaces, where the carrier owns and operates the cells and the airport operator provides cell site space rental, cable and equipment easement, power, or other commercial agreements. • DAS is a variation of the mobile carrier access, where the access network in the indoor space is provided by a neutral host operating at the airport, which shares the radio access among participating mobile carriers. The core network and subscriber management still belong to the mobile carrier. However, this enables radio infrastructure consolidation and potential revenue-sharing formulas between the neutral host (and potentially the airport operator) with the mobile carrier. DAS architectures make sense for large surfaces, while smaller air- ports can improve coverage by other means (e.g., signal boosting or small-cell installation by the carrier). • In the case of direct radio access to public-safety networks, users are LMR or cellular (FirstNet) devices operating on an assigned channel (e.g., first responders carrying a radio registered to use the assigned frequency). This can be used to provide first responders with tactical com- munications on the airport premises for incident response, dependent on the coverage and criticality supported by the mobile operator. • This architecture also allows for private cellular networks operated by mobile carriers. This design supports enterprise networks seeking disaggregation of services, where traffic and sub- scribers are managed by airport operators or tenants, to operate in a dedicated frequency band licensed to the mobile carrier. Private cellular networks can serve as a backbone to enterprise Wi-Fi networks. This model can support use cases for business operations such as enterprise services, sensing and automation, and reliable communications. Radio access can be provided through large, small, or DAS cells, while the core network is operated by the mobile carrier. This may be a cost-effective solution for airport operators and tenants operating sensor networks (5G, 4G LTE CAT-M or NB-IoT, LoRa, and Sigfox), although the performance depends on the appropriate cellular coverage of the sensor locations. 1.3.2.2 Private Enterprise/Consumer Network Infrastructure Under this deployment architecture, the airport operator manages (either directly or through a delegated entity) connectivity services for enterprise and/or consumer applications in its LAN (Figure 25). A tenant can also create a private enterprise network independently. This model gives the wireless service provider a high degree of control over the users and the traffic operat- ing on the network while enabling a wide range of use cases from internet access and enterprise networks, to monitoring, sensing, and automation. The provider can also configure customized service access and security policies. This model allows airports to build wireless capacity and sell it to network users. For airport operators seeking targeted tenant services and revenue genera- tion, wireless services can be commercialized as part of lease term agreements or tenant services agreements. In most cases, a wireless network of this type will use unlicensed bands or GAA in the shared CBRS spectrum to avoid dependence on spectrum owned by third parties. However, this limits the reliability of the applications provided, due to potential performance degradations inherent to the use of these bands. This can be mitigated by securing a PAL in shared CBRS spectrum,

Taxonomy of Wireless Technologies and Their Uses in Airports 75   by network planning and spectrum governance, or by enforcing broadcasting rights to control emissions in unlicensed bands within the airport spaces. Private networks in unlicensed spectrum are prevalent at airports today as demonstrated by Wi-Fi networks oered for guest internet access and airport/tenant enterprise applications. In addition, roaming agreements with mobile carriers based on WBA OpenRoaming standards enable the ooading of subscribers to a private network. is creates nonaeronautical revenue generation opportunities based on managing the subscriber trac on behalf of the mobile carrier for a price, enabling a framework for airport operators or delegated entities to market their wire- less capacity. is business model is applied by neutral hosts, which typically operate both private Wi-Fi and mobile carrier DAS in managed venues. In addition, emerging private sensor networks for smart building, monitoring, and control make use of BLE, Zigbee, and LoRa networks connected to a Wi-Fi enterprise network. In the future, the use of 5G and HaLow in the unlicensed spectrum will open options for mobile com- munication and IoT applications using more versatile radio interfaces. Private networks in the shared CBRS spectrum are an emerging opportunity to provide private cellular enterprise networks in a less crowded spectrum, thus increasing service reli- ability. is approach allows airports to ooad application trac that requires reliability and security (e.g., airport operations or surveillance) from the guest access Wi-Fi network. is is further increased by securing a PAL covering the airport grounds, which has an additional cost compared to using free unlicensed or GAA-shared spectrum. CBRS is a shared spectrum, which allows the deployment of private cellular networks without the need for a mobile carrier. A cellu- lar CBRS private network can provide wireless service to end-user devices supporting this band, or as backhaul to Wi-Fi APs in the unlicensed spectrum. Network design for CBRS is like that of other cellular networks, with the responsibility of appropriate planning for coverage and capacity falling on the owner of the network. Access to private CBRS networks can also be oered in an existing DAS infrastructure sharing radio access with mobile carriers in the same spaces. Figure 25. Private/enterprise consumer network.

76 Transformation in Wireless Connectivity: Guide to Prepare Airports 1.3.2.3 Private Critical Network Infrastructure is architecture is like that of the private enterprise/consumer network in that the airport operator or delegated entity is responsible for connectivity. However, this is a specic network created for highly secure, critical services specic to airport personnel ensuring reliable opera- tions, such as tactical communications, perimeter surveillance, UAV command and control, and ight deck communications (Figure 26). In addition, this network architecture requires an exclusive license to ensure the spectrum is allocated solely for critical network services. In this case, spectrum regulations need to be governed by the airport operator, sometimes in coordina- tion with government entities (e.g., FCC, FAA, other government agencies such as TSA/CBP, or public-safety entities in the area). Typical technologies deployed in this architecture are cellular, AeroMACS, and LMR. A licensed frequency should be secured through a PAL if this network is supported by cellular LTE/5G technology making use of the shared CBRS spectrum. In this case, wireless connec- tivity should be provided directly to a CBRS end-user device to ensure end-to-end critical com- munications. IoT applications with end-to-end reliability can only be supported in this scenario using 5G. 1.3.2.4 Distributed Infrastructure is architecture does not need a service provider infrastructure to operate, as it relies on ad hoc, self-congurable wireless networks managed directly by the user (Figure 27). us, the end user is ultimately responsible for the performance of the network. ese networks are characterized by a relatively short range of communications and operate in an unlicensed spectrum. However, the end user is also responsible for any interference that it may cause with licensed spectrum systems operating in the environment. Direct-mode communications are typical in LMR (P25) networks operating in unassigned channels. ese can be direct PTT communications for day-to-day tactical operations by airport or tenant sta, or for rst responder communications in situations of degraded infrastructure Figure 26. Private critical network.

Taxonomy of Wireless Technologies and Their Uses in Airports 77   or ad hoc need for communications (e.g., in an incident area). In the future, the 5G sidelink feature is expected to also support this functionality over cellular devices. In this sense, direct- mode communications provide the highest reliability in degraded situations. Other direct communications involve RFID/NFC for tag reading and tracking, and drone communications (command and control, payload, and telemetry) over Wi-Fi, Bluetooth, or dedicated radio technology. Mesh network topologies are supported by PAN technologies (BLE and Zigbee) for self- configurable, ad hoc sensor networks covering large spaces without the need for a relay infra- structure. These networks are usually connected to a private enterprise network to share data with the user and provide a dashboard or cloud management. 1.3.3 A Framework for the Wireless-Connected Airport This section consolidates the value propositions, airport operator roles, and deployment archi- tectures likely to be used to create business models for providing wireless services at an airport. Table 11 summarizes some of the potential business models that airport operators can follow to provide wireless connectivity on their premises for their users and to generate monetary and non-monetary values through these services. Table 11 also provides examples of applications and value-added services that can be offered by airport operators or associated stakeholders under each business model. As wireless technologies become more pervasive and are increasingly considered an inte- grated asset in the business strategy of airport operators, the business models previously indi- cated, and potentially new ones, will be implemented. This will require an evolution in terms of technical, organizational, and commercial maturity for the industry to leverage the capabilities of wireless more effectively. This topic was discussed extensively as part of this project, including at a virtual round table with airport and technology stakeholders. As a result, a framework for the evolution of wireless connectivity and business models has been created. It outlines a model for the stages of incremental capabilities in the provision of wireless services in the airport environment Figure 27. Distributed network.

78 Transformation in Wireless Connectivity: Guide to Prepare Airports Business model Airport wireless service offering Real-estate rental Minimizes network operation costs and targets nonaeronautical revenue from service providers and tenants via cell tower space rental, integrated cabling and utilities, and easement agreements. Managed services Targets control of generation of the value proposition from wireless networks (customer satisfaction, revenue and cost savings, and reliability) by setting and ensuring performance levels for network users. Focuses on integration of data services and infrastructure (in a typical scenario, airport tenants and the airport share a common wireless access system). The network is owned and planned by the airport operator; it may be run by a delegated entity. Managed services are bundled as utilities as part of lease term agreements. Shared services Similar to the above but property owner provides a common set of sophisticated technical services dedicated to tenants. Cost and revenue-sharing agreements are in place. Shared tenant services can be implemented either as a new revenue stream or as a method to recover costs and improve customer service. Each new service provided for a tenant is added to the existing infrastructure (procurement, installation, maintenance, administration). Thus, pricing for the additional wireless services reflects at least the recovery of the additional costs, along with any margin. Network as a service (NaaS) Optimizes network resources by managing them as a whole. Has a high level of virtualization, cloud, and edge applications. Customizes wireless connectivity services to each client to maximize revenue/reliability and minimize cost. Service brokerage Does not own or operate the network but contributes to the value chain as a facilitator. Serves as an intermediary between service providers and consumers, external parties such as advertising agencies, and government authorities for promoting innovation and accessing funds. Targets customer satisfaction and revenue generation. Freemium Can be applied to managed/shared services or NaaS models. Targets nonaeronautical revenue generation. Offers basic wireless connectivity services for free to tenants and visitors and enhanced services (e.g., security, dedicated capacity) for a fee. Fractionalization The airport, as the network owner, commercializes dedicated resources for specific customers. Targets aeronautical and nonaeronautical revenue. May include revenue-sharing formulas if the network is planned and operated by a neutral host. Standardization Targets cost-efficiency and reliability by building economies of scale across the airport industry using the same technologies and deployment architectures. Automation Targets cost-efficiency and reliability by minimizing the participation of humans in airport processes. Targets economies of scale within the airport. Table 11. Business models for airport wireless connectivity. and is intended to provide a high-level timeline of what steps need to be taken to achieve subsequent maturity levels. Table 12 shows a summary of the wireless connectivity maturity framework. The wireless connectivity maturity framework can be mapped directly to the airport digital maturity framework (Amadeus/Little 2018) widely used in the airport industry. According to the digital maturity model, airports reach the initial digitalization levels (Airport 3.0) focused on the enhancement of passenger experience and flow processing. Airport 4.0 extends digitaliza- tion to all airport stakeholders and focuses on a culture of efficiency and the generation of new revenue streams. Note that the incremental steps are a generalization of what is possible for different types and sizes of airports. However, the actual evolution may be affected by specific events that accelerate or slow the adoption of wireless capabilities. These events can be defined by characteristics of the airport or by exogenous events such as market forces or, more recently, the COVID-19 pandemic.

Taxonomy of Wireless Technologies and Their Uses in Airports 79   Wireless maturity level Main capabilities Corresponds to airport digital maturity level 0.0 Initial Still improving wideband internet access at the facility. Airport limited to managing operations and real estate, not concerned with connectivity. Users connect to ISPs and mobile carriers directly; set up their own wireless infrastructure at offices and key locations (e.g., MRO). Heterogeneous coverage and capacity across facilities. 1.0/2.0 Operations mostly analog, with some process improvements in specific airport areas (e.g., kiosks). 1.0 Essential High-speed, secure access via the airport's private network for guests and staff across the terminal. Cellular coverage with at least low capacity in the entire area. Basic tactical communications for staff and first responders in the airfield. Low-volume sensor networks for smart building and health tracking. Airport operator has some IT resources, performs limited spectrum management, and has commercial agreements with wireless providers. 3.0 Initial digitalization focused on the enhancement of passenger experience and airport operations; the target is the improvement of performance and reduction of response times for processes. 2.0 Enhanced Improved capacity and reduced latency for more stringent wireless applications; increased reliability at critical locations. Agreements with mobile carriers for high-capacity cellular coverage in the entire area. Limited cellular/Wi-Fi roaming with specific mobile carriers; dedicated planning for dual network optimization depending on zone usage. Airport offers managed wireless services and initial IoT for the reliability of operations. 3.0 Mature Centralized wireless platform, auto-adjusting for variable capacity and security. Comprehensive cybersecurity planning. Decreasing wireless cost improves financial flexibility. Offers tailored wireless service and scaled-up capacity. Federated roaming, user interoperability between networks, and integrated authentication. Most airport and tenant applications moved to the cloud. Expanded IoT for reliability and smart building efficiency, cloud-based management. 4.0 Full digitalization involving all stakeholders; targets cross-platform implementations to host common applications; targets efficiency and revenue generation by centralization of resources and consolidation of digital service offerings. 4.0 Visionary Large-scale IoT, big data management, and airport-wide AI. Cloud and edge applications for varying data and safety requirements. Edge data centers in the airport for high-capacity, low-latency safety applications. With full network interoperability, the user has a completely seamless experience and expects total ubiquity and performance. Network includes a high variety of users, including automated mobile things (robots, vehicles). Novel revenue streams allow airports to commercialize wireless capacity as an asset in numerous ways, become a communications hub orchestrating data (smart city), and seek new commercial formulas and legal agreements. Table 12. Summary of wireless connectivity maturity framework.