Overlaying an air to ground communication system on spectrum assigned to satellite systems

Patent metadata

Field	Value
Publication number	US-9882630-B2
Application number	US-201113210628-A
Country	US
Kind code	B2
Filing date	Aug 16, 2011
Priority date	Aug 16, 2011
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

An air to ground communication system provides internet access to aircraft from ground based stations. The air to ground system shares spectrum with uplink portions of a satellite communication spectrum. Interference mitigation techniques are employed to avoid interference between the ground based communications and satellite communications. Fade mitigation techniques are employed to provide communication to aircraft at low angles of elevation in the presence of rain.

First claim

What is claimed is:

1. A system for wireless communication comprising:
a ground base station configured to transmit and receive signals on a satellite uplink band with an aircraft transceiver, the ground base station further configured:
to handoff the aircraft transceiver to another ground base station for reducing interference to satellite communications on the satellite uplink band, when the ground base station and the aircraft transceiver are aligned with a non-geostationary satellite and when the other ground base station is available for handoff; and
to temporarily reduce a data rate or discontinue transmission to the aircraft transceiver until the ground base station and the aircraft transceiver are no longer aligned with the non-geostationary satellite when the other ground base station is not available.

2. The system of claim 1 , in which the ground base station is further configured to spread transmit power across a frequency band to reduce power spectral density of transmissions.

3. The system of claim 1 , in which the ground base station is further configured to direct transmissions away from a geostationary arc of Earth.

4. The system of claim 3 , further comprising:
transmit antennas of the ground base station directed away from the geostationary arc.

5. The system of claim 4 , further comprising:
receiving antennas of the ground base station directed toward the geostationary arc.

6. The system of claim 5 , in which the receiving antennas and transmit antennas are configured as separate antennas.

7. The system of claim 5 , in which the receiving antennas and transmit antennas are configured separately by beam forming on a single antenna.

8. The system of claim 1 , in which the ground base station is further configured for reducing interference to satellite communications by reducing a transmit power on a communication link between the ground base station and the aircraft transceiver until the ground base station and the aircraft transceiver are no longer aligned with the non-geostationary satellite, the transmit power reduced when no other ground base station is available for handoff.

9. The system of claim 1 , in which the ground base station is further configured for reducing interference to satellite communications by directing ground base station antennas away from the equator.

10. A system for wireless communication comprising:
an aircraft transceiver in communication with a ground base station, configured to transmit and receive signals on a satellite uplink band, the aircraft transceiver further configured:
to handoff to another ground base station for reducing interference to satellite communications on the satellite uplink band, when the ground base station and the aircraft transceiver are aligned with a non-geostationary satellite and when the other ground base station is available for handoff; and
to temporarily reduce a data rate or discontinue transmission until the ground base station and the aircraft transceiver are no longer aligned with the non-geostationary satellite when the other ground base station is not available.

11. The system of claim 10 , in which the aircraft transceiver is further configured to spread transmit power across a frequency band to reduce power spectral density of transmissions.

12. The system of claim 10 , in which the aircraft transceiver is further configured to direct transmissions away from a geostationary arc of Earth.

13. The system of claim 12 , further comprising:
transmit antennas of the aircraft transceiver directed away from the geostationary arc.

14. The system of claim 13 , further comprising:
receiving antennas of the aircraft transceiver directed toward the geostationary arc.

15. The system of claim 14 , in which the receiving antennas and transmit antennas are configured as separate antennas.

16. The system of claim 14 , in which the receiving antennas and transmit antennas are configured separately by beam forming on a single antenna.

17. The system of claim 10 , in which the aircraft transceiver is further configured for reducing interference to satellite communications by reducing a transmit power on a communication link between the ground base station and the aircraft transceiver until the ground base station and the aircraft transceiver are no longer aligned with the non-geostationary satellite, the transmit power reduced when no other ground base station is available for handoff.

18. The system of claim 10 , in which the aircraft transceiver is further configured for reducing interference to satellite communications by directing transmissions towards the equator.

19. A method for wireless communication comprising:
transmitting and receiving signals by a ground base station on a satellite uplink band with an aircraft transceiver;
handing off the aircraft transceiver to another ground base station for reducing interference to satellite communications on the satellite uplink band, when the ground base station and the aircraft transceiver are aligned with a non-geostationary satellite and when the other ground base station is available for handoff; and
temporarily reducing a data rate or discontinuing transmission to the aircraft transceiver until the ground base station and the aircraft transceiver are no longer aligned with the non-geostationary satellite when the other ground base station is not available.

20. The method of claim 19 , further comprising:
spreading transmit power across a frequency band to reduce power spectral density of transmissions.

21. The method of claim 19 , further comprising:
directing transmissions away from a geostationary arc of Earth.

22. The method of claim 21 , further comprising:
directing receiving antennas of the ground base station toward the geostationary arc.

23. The method of claim 22 , further comprising:
configuring the receiving antennas and transmit antennas as separate antennas.

24. The method of claim 22 , further comprising:
configuring the receiving antennas and transmit antennas separately by beam forming on a single antenna.

25. The method of claim 19 , in which the ground base station is further configured for reducing interference to satellite communications by reducing a transmit power on a communication link between the ground base station and the aircraft transceiver until the ground base station and the aircraft transceiver are no longer aligned with the non-geostationary satellite, the transmit power reduced when no other ground base station is available for handoff.

26. The method of claim 19 , in which the ground base station is further configured for reducing interference to satellite communications by directing ground base station antennas away from the equator.

27. An apparatus for wireless communication comprising:
means for transmitting and receiving signals by a ground base station on a satellite uplink band with an aircraft transceiver;
means for handing off the aircraft transceiver to another ground base station for reducing interference to satellite communications on the satellite uplink band, when the ground base station and the aircraft transceiver are aligned with a non-geostationary satellite and when the other ground base station is available for handoff; and
means for temporarily reducing a data rate or discontinuing transmission to the aircraft transceiver until the ground base station and the aircraft

Assignees

• Jalali Ahmad
• Schiff Leonard N
• Ames William G
• Qualcomm Inc

Inventors

• Jalali Ahmad
• Schiff Leonard N
• Ames William G

Classifications

• H04B7/18502

  Airborne stations · CPC title

• H04B7/18508 Primary

  with satellite system used as relay, i.e. aeronautical mobile satellite service · CPC title

• H04W36/20

  for optimising the interference level · CPC title

• H04W16/14

  Spectrum sharing arrangements {between different networks} · CPC title

• H04W36/30

  by measured or perceived connection quality data · CPC title