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Analysis of Potential Interference Issues Related to FCC Order 20-48 (2023) / Chapter Skim
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Pages 60-64

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From page 60...
... Those GPS receivers selected must be tested under fair, realistic conditions. Metrics depend on what needs to be tested and how that metric relates to harmful interference.
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From page 61...
... GPS In-Band Interference Noise levels in the GPS band are approximately −174 dBm/Hz, so at a distance of 10 meters from a Ligado transmitter limited to −130 dBm/Hz in the GPS band (56.5 dB free space path loss at 1584.5 MHz) , the interference from the Ligado user or base station will be at least 12 dB below the noise floor.
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From page 62...
... Devices 80 GPS receivers were tested 14 in different categories such 27 devices of various receiver Tested simultaneously. Cellular, as general navigation, high- classes.
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From page 63...
... position errors. metric was not linked to harmful interference for Unclear if these receivers have Demonstrated mitigation strategies GPS.
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From page 64...
... In existing GPS receiver designs, aliasing of out-of-band signals into the GPS band is typically not a problem. However, the large power discrepancies between the Ligado base station/user and the GPS signal make it possible for aliased power to be folded into the GPS band and may adversely affect receivers not designed for that environment.
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Key Terms

  • harmful interference
  • gps receiver
  • fcc order
  • gps receivers
  • gps band

  • gps signal
  • position error
  • adjacent band
  • signal processing
  • base station

  • single ligado
  • base stations
  • path loss
  • receiver performance
  • free space

  • receiver design
  • ligado emissions
  • ligado signals
  • power levels
  • ligado signal

  • ligado downlink
  • existing gps
  • rnss band
  • power level
  • space path

  • satellite services
  • receiver operation
  • band interference
  • satellite service
  • radionavigation satellite


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