Telecommunications Research and Engineering at the Institute for Telecommunication Sciences of the Department of Commerce Meeting the Nation's Telecommunications Needs (2015) / Chapter Skim
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Appendix D: The Value and Use of Wireless Technology
Appendix D: The Value and Use of Wireless Technology
Pages 51-59
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From page 51... ...
The military buildup due to World War I caused wireless frequencies to be reserved primarily for government use. In the United States, the federal assignment of frequencies to commercial entities began in 1922, when 833 kHz was defined as the frequency to be used for "Entertainment" and 619 kHz as the frequency for "Market and Weather." These frequencies were in the kHz regime because wireless systems at that time could only operate at very low frequencies.
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From page 52... ...
, as well as standard frequency and time signals, discrete frequencies that require exclusivity for radio astronomy, and amateur radio. Through extensive negotiation, the entire radio spectrum has been divided into specific blocks of frequencies for each application; most often, several blocks at different carrier frequencies can service the same application.
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From page 53... ...
FirstNet will build, operate, and maintain the first high-speed, nationwide wireless broadband network dedicated to public safety. The spectrum license issued to FirstNet is for two 10 MHz channels of paired spectrum at 758-768 MHz and 788-798 MHz, plus guard bands at 768-769 MHz and 798-799 MHz to reduce interference from adjacent channels.
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From page 54... ...
Higher carrier frequencies designated with larger bandwidths can carry more information, but walls and other obstacles may block it. The highest frequencies -- millimeter waves (mmband)
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From page 55... ...
• Scientific applications. There is a multitude of scientific users of radio spectrum including radio astronomers and Earth scientists using remote sensing.
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From page 56... ...
A sharp heat boundary is created between the affected tissue and that surrounding it allowing for surgeons to operate with a high level of precision and control, without much sacrifice to the adjacent normal tissue. The lower operating temperatures of RF, as compared to traditional electrosurgical or laser surgery tools, enables surgeons to remove, shrink, or sculpt soft tissue while simultaneously sealing blood vessels.
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From page 57... ...
and WiMax mobile networks." 7 Similar to the WLAN unlicensed products moving from 1 to 5 GHs frequencies in early generation to 60 GHz today, the cellular industry is moving 4 United States CFR Title 47, Part 15 -- Radio Frequency Devices, Subpart E -- Unlicensed National Information Devices, Paragraph 15.407 -- General technical requirements. 5 European Telecommunications Standards Institute, "Millimetre Wave Transmission," Technology Leaflet, 2015, http://www.etsi.org/images/files/ETSITechnologyLeaflets/MillimetreWaveTransmission.pdf.
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From page 58... ...
Thus, it permits aggressive frequency reuse while simultaneously operating networks that do not hinder each other. 11 Highly directional antennas needed for path loss mitigation actually work to promote security as long as network protocols and front-end hardware enabled antenna arrays are flexibly steered.
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From page 59... ...
Murdock, Introduction to Millimeter Wave Wireless Communications, October 6, 2014, http://www.informit.com/articles/article.aspx?
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