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From page 1... ... The order authorizes Ligado to provide terrestrial base station to mobile earth station downlink transmissions in the 1526–1536 MHz band within the mobile satellite services (MSS) -allocated 1525–1559 MHz band and mobile earth station to terrestrial base station uplink transmissions in the 1627.5–1637.5 and 1646.5–1656.5 MHz bands of the 1626.5–1660.5 MHz band. Read the entire page →
From page 2... ... • Task 3: Assess the feasibility, practicality, and effectiveness of the measures in the FCC order to mitigate harmful interference effects on DoD devices, opera tions, and activities. In providing responses to these tasks, the committee stresses three important points: • Throughout this report, the term "Harmful Interference" -- when capitalized -- is a defined term used by the FCC and is specifically not the same thing as the general term "interference," which describes what happens in a receiver when some other signal affects the intended received signal in a way that 2 A N A LY S I S O F P OT E N T I A L I N T E R F E R E N C E I S S U E S R E L AT E D TO F C C O R D E R 2 0 - 4 8 Read the entire page →
From page 3... ... Radio Regulations" and "operating in accordance with this chapter." However, the committee proceeded under the assumption that it has been charged with determining whether existing radionavigation satellite services (RNSS) or MSS would be harmed by Ligado interference inde pendent of any legal ruling and concentrated on the physics and engineering questions of harmful interference. Read the entire page →
From page 4... ... As such, these approaches impede progress in making more efficient and effective use of the spectrum. A new ap plicant for emissions in a new adjacent channel will have great difficulty in determining the emitter power levels and stand-off distances that will be guaranteed not to cause Harmful Interference to the installed base of GPS receivers. Read the entire page →
From page 5... ... The committee also reached the following conclusion regarding the state of the art in GPS receivers: Conclusion 3: It is within the state-of-the-practice of current technology to build a receiver that is robust to Ligado signals for any GPS application, and all GPS receiver manufacturers could field new designs that could co-exist with the authorized Ligado signals and achieve good performance even if their existing designs cannot. Turning to impacts on MSS, the committee concluded that the Globalstar system is unlikely to experience harmful interference, because only its uplink is in the L-band and it uses code-division multiple access (CDMA) Read the entire page →

From page 1...

... The order authorizes Ligado to provide terrestrial base station to mobile earth station downlink transmissions in the 1526–1536 MHz band within the mobile satellite services (MSS) -allocated 1525–1559 MHz band and mobile earth station to terrestrial base station uplink transmissions in the 1627.5–1637.5 and 1646.5–1656.5 MHz bands of the 1626.5–1660.5 MHz band.

Read the entire page →

From page 2...

... • Task 3: Assess the feasibility, practicality, and effectiveness of the measures in the FCC order to mitigate harmful interference effects on DoD devices, opera tions, and activities. In providing responses to these tasks, the committee stresses three important points: • Throughout this report, the term "Harmful Interference" -- when capitalized -- is a defined term used by the FCC and is specifically not the same thing as the general term "interference," which describes what happens in a receiver when some other signal affects the intended received signal in a way that 2 A N A LY S I S O F P OT E N T I A L I N T E R F E R E N C E I S S U E S R E L AT E D TO F C C O R D E R 2 0 - 4 8

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From page 3...

... Radio Regulations" and "operating in accordance with this chapter." However, the committee proceeded under the assumption that it has been charged with determining whether existing radionavigation satellite services (RNSS) or MSS would be harmed by Ligado interference inde pendent of any legal ruling and concentrated on the physics and engineering questions of harmful interference.

Read the entire page →

From page 4...

... As such, these approaches impede progress in making more efficient and effective use of the spectrum. A new ap plicant for emissions in a new adjacent channel will have great difficulty in determining the emitter power levels and stand-off distances that will be guaranteed not to cause Harmful Interference to the installed base of GPS receivers.

Read the entire page →

From page 5...

... The committee also reached the following conclusion regarding the state of the art in GPS receivers: Conclusion 3: It is within the state-of-the-practice of current technology to build a receiver that is robust to Ligado signals for any GPS application, and all GPS receiver manufacturers could field new designs that could co-exist with the authorized Ligado signals and achieve good performance even if their existing designs cannot. Turning to impacts on MSS, the committee concluded that the Globalstar system is unlikely to experience harmful interference, because only its uplink is in the L-band and it uses code-division multiple access (CDMA)

Read the entire page →

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