Coordinated satellite-terrestrial frequency reuse

• US 7,149,526 B2
• Filed: 08/01/2001
• Issued: 12/12/2006
• Est. Priority Date: 08/02/2000
• Status: Expired due to Term

• Current Assignee: ATC Technology Corporation (FedEx Corporation), Telecom Satellite Ventures, Inc.
• Original Assignee: ATC Technology Corporation (FedEx Corporation)
• Inventors: Olexa, George R., Karabinis, Peter D., Singh, Rajendra, Badipour, Bahman
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US10/343,471
• Publication Number:
  US 20040023658A1
• Time in Patent Office: 1,959 Days
• Field of Search: 455/427, 455/429, 455/430, 455/431, 455/447, 455/448, 455/426.1, 455/12.1
• US Class Current: 455/447
• CPC Class Codes: H04B 7/18539 Arrangements for managing radio, resources, i.e. for establishing or releasing a connection
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00
• CPC Class Codes: H04B 7/2041 Spot beam multiple access
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks

Abstract

A system and method of operation for efficiently reusing and/or sharing at least a portion of the frequency spectrum between a first satellite spot beam and a second satellite spot beam, and/or an underlay terrestrial network associated with a second satellite spot beam. The spectrum is efficiently reused and/or shared between respective spot beams and/or associated underlay terrestrial systems in a manner minimizes interference between the respective satellite and terrestrial systems.

Claims

1. A method of operating a terrestrially-based wireless communications system having a terrestrial coverage area overlaid on a first satellite coverage area of a satellite-based wireless communications system having a plurality of satellite coverage areas, the method comprising:

reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas.

2. A method according to claim 1, wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas comprises preferentially reusing frequencies from those of the adjoining satellite coverage areas having greater geographical separation from the terrestrial coverage area in the terrestrial coverage area.

3. A method according to claim 1, wherein the terrestrial coverage area is confined to a central portion of the first satellite coverage area, and wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas comprises enabling reuse of all of the frequencies of the adjoining satellite coverage areas in the terrestrial coverage area.

4. A method according to claim 3, wherein the terrestrial coverage area comprises about 25% or less of the first satellite coverage area.

5. A method according to claim 1, wherein the terrestrial coverage area is nearest a first one of the adjoining satellite coverage areas, and wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas comprises preferentially reusing frequencies from the adjoining satellite coverage areas other than the first one of the adjoining satellite coverage areas.

6. A method according to claim 5, wherein the terrestrial coverage area comprises a first terrestrial coverage area disposed on a peripheral portion of the first satellite coverage area nearest the first one of the adjoining coverage areas and a second terrestrial coverage area confined to a central portion of the first satellite coverage area, and wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas comprises:

preferentially reusing frequencies from adjoining satellite coverage areas other than the first one of the adjoining satellite coverage areas in the first terrestrial coverage area; and

enabling reuse of all of the frequencies of the adjoining satellite coverage areas in the second terrestrial coverage area.

7. A method according to claim 6, wherein the second terrestrial coverage area comprises about 25% or less of the first satellite coverage area.

8. A method according to claim 6, wherein the first satellite coverage area comprises a plurality of peripheral areas adjoining respective ones of the adjoining satellite coverage areas and disposed around the central portion, wherein the first terrestrial coverage area is disposed in a first peripheral area of the plurality of peripheral areas, and wherein preferentially reusing frequencies from the adjoining satellite coverage other than the first one of the adjoining satellite coverage areas in the first terrestrial coverage area comprises preferentially reusing frequencies from the adjoining satellite coverage areas that do not adjoin the first peripheral area.

9. A method according to claim 1, wherein the first satellite coverage area comprises a plurality of sectors adjoining respective ones of the adjoining satellite coverage areas, wherein the terrestrial coverage area is located in a first sector of the plurality of sectors of the first satellite coverage area, and wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas comprises preferentially reusing frequencies from the adjoining satellite coverage areas that do not adjoin the first sector.

10. A method according to claim 1, wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas comprises reusing downlink and uplink frequencies of frequency pairs used in one of the adjoining satellite coverage areas in respective first and second terrestrial coverage areas overlaid on the first satellite coverage area.

11. A method according to claim 1, wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the adjoining satellite coverage areas comprises reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas and on at least one of a loading and a capacity constraint of the adjoining satellite coverage areas.

12. A method according to claim 1, wherein reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on geographical separation between the terrestrial coverage area and the adjoining satellite coverage areas comprises reusing frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas and on at least one of a load balancing criterion, a frequency reserve criterion and a signal interference criterion.

13. A method according to claim 1, wherein the terrestrially-based wireless communications system comprises a terrestrial base station that serves the terrestrial coverage area.

14. A wireless communications system configured to implement the method of claim 1.

15. A communications system, comprising:

a satellite-based wireless communications system having a plurality of satellite coverage areas; and

a terrestrially-based wireless communications system having a terrestrial coverage area overlaid on a first satellite coverage area of the plurality of satellite coverage areas and that is configured to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas.

16. A system according to claim 15, wherein the terrestrially-based wireless communications system is configured to preferentially reuse frequencies from those of the adjoining satellite coverage areas having greater geographical separation from the terrestrial coverage area in the terrestrial coverage area.

17. A system according to claim 15, wherein the terrestrial coverage area is confined to a central portion of the first satellite coverage area, and wherein the terrestrially-based wireless communications system is configured to enable reuse of all of the frequencies of the adjoining satellite coverage areas in the terrestrial coverage area.

18. A system according to claim 17, wherein the terrestrial coverage area comprises about 25% or less of the first satellite coverage area.

19. A system according to claim 15, wherein the terrestrial coverage area is nearest a first one of the adjoining satellite coverage areas, and wherein the terrestrially-based wireless communications system is configured to preferentially reuse frequencies from the adjoining satellite coverage areas other than the first one of the adjoining satellite coverage areas.

20. A system according to claim 19, wherein the terrestrial coverage area comprises a first terrestrial coverage area disposed on a peripheral portion of the first satellite coverage area nearest the first one of the adjoining coverage areas and a second terrestrial coverage area confined to a central portion of the first satellite coverage area, and wherein the terrestrially-based wireless communications system is configured to preferentially reusing frequencies from adjoining satellite coverage areas other than the first one of the adjoining satellite coverage areas in the first terrestrial coverage area and to enable reuse of all of the frequencies of the adjoining satellite coverage areas in the second terrestrial coverage area.

21. A system according to claim 20, wherein the second terrestrial coverage area comprises about 25% or less of the first satellite coverage area.

22. A system according to claim 20, wherein the first satellite coverage area comprises a plurality of peripheral areas adjoining respective ones of the adjoining satellite coverage areas and disposed around the central portion, wherein the first terrestrial coverage area is disposed in a first peripheral area of the plurality of peripheral areas, and wherein the terrestrially-based wireless communications system is configured to preferentially reuse frequencies from the adjoining satellite coverage areas that do not adjoin the first peripheral area.

23. A system according to claim 15, wherein the first satellite coverage area comprises a plurality of sectors adjoining respective ones of the adjoining satellite coverage areas, wherein the terrestrial coverage area is located in a first sector of the plurality of sectors of the first satellite coverage area, and wherein the terrestrially-based wireless communications system is configured to preferentially reuse frequencies from the adjoining satellite coverage areas that do not adjoin the first sector.

24. A system according to claim 15, wherein the terrestrially-based wireless communications system is configured to reuse downlink and uplink frequencies of a frequency pair used in one of the adjoining satellite coverage areas in respective first and second terrestrial coverage areas overlaid on the first satellite coverage area.

25. A system according to claim 15, wherein the terrestrially-based wireless communications system is configured to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas on at least one of a loading and a capacity constraint of the adjoining satellite coverage areas.

26. A system according to claim 15, wherein the terrestrially-based wireless communications system is configured to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas and on at least one of a load balancing criterion, a frequency reserve criterion and a signal interference criterion.

27. A system according to claim 15, wherein the terrestrially-based wireless communications system comprises a terrestrial base station that serves the terrestrial coverage area.

28. A system according to claim 15, further comprising a network operations center operative to assign frequencies to the satellite-based wireless communications system and the terrestrially-based wireless communications system such that the terrestrially-based wireless communications system is configured to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas.

29. A communications system, comprising:

at least one terrestrially-based station having a terrestrial coverage area overlaid on a first satellite coverage area of the plurality of satellite coverage areas served by a satellite-based wireless communications system; and

a controller configured to cause the at least one terrestrially-based station to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas.

30. A system according to claim 29, wherein the controller is configured to cause the at least one terrestrially-based station to preferentially reuse frequencies from those of the adjoining satellite coverage areas having greater geographical separation from the terrestrial coverage area in the terrestrial coverage area.

31. A system according to claim 30, wherein the terrestrial coverage area is confined to a central portion of the first satellite coverage area, and wherein the controller is configured to enable the at least one terrestrially-based station to reuse of all of the frequencies of the adjoining satellite coverage areas in the terrestrial coverage area.

32. A system according to claim 31, wherein the terrestrial coverage area comprises about 25% or less of the first satellite coverage area.

33. A system according to claim 29, wherein the terrestrial coverage area is nearest a first one of the adjoining satellite coverage areas, and wherein the controller is configured to cause the at least one terrestrially-based station to preferentially reuse frequencies from the adjoining satellite coverage areas other than the first one of the adjoining satellite coverage areas.

34. A system according to claim 33, wherein the terrestrial coverage area comprises a first terrestrial coverage area disposed on a peripheral portion of the first satellite coverage area nearest the first one of the adjoining coverage areas and a second terrestrial coverage area confined to a central portion of the first satellite coverage area, and wherein the controller is configured to cause the at least one terrestrially-based station to preferentially reuse frequencies from adjoining satellite coverage areas other than the first one of the adjoining satellite coverage areas in the first terrestrial coverage area and to enable the at least one terrestrially-based station to reuse of all of the frequencies of the adjoining satellite coverage areas in the second terrestrial coverage area.

35. A system according to claim 34, wherein the second terrestrial coverage area comprises about 25% or less of the first satellite coverage area.

36. A system according to claim 34, wherein the first satellite coverage area comprises a plurality of peripheral areas adjoining respective ones of the adjoining satellite coverage areas and disposed around the central portion, wherein the first terrestrial coverage area is disposed in a first peripheral area of the plurality of peripheral areas, and wherein the controller is configured to cause the at least one terrestrially-based station to preferentially reuse frequencies from the adjoining satellite coverage areas that do not adjoin the first peripheral area.

37. A system according to claim 29, wherein the first satellite coverage area comprises a plurality of sectors adjoining respective ones of the adjoining satellite coverage areas, wherein the terrestrial coverage area is located in a first sector of the plurality of sectors of the first satellite coverage area, and wherein the controller is configured to cause the at least one terrestrially-based station to preferentially reuse frequencies from the adjoining satellite coverage areas that do not adjoin the first sector.

38. A system according to claim 29, wherein the controller is configured to cause the at least one terrestrially-based station to reuse downlink and uplink frequencies of a frequency pair used in one of the adjoining satellite coverage areas in respective first and second terrestrial coverage areas overlaid on the first satellite coverage area.

39. A system according to claim 29, wherein the controller is configured to cause the at least one terrestrially-based station to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas on at least one of a loading and a capacity constraint of the adjoining satellite coverage areas.

40. A system according to claim 29, wherein the controller is configured to cause the at least one terrestrially-based station to reuse frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas and on at least one of a load balancing criterion, a frequency reserve criterion and a signal interference criterion.

41. A system according to claim 29, wherein the controller comprises a network operations center operative to assign frequencies to the satellite-based wireless communications system and the at least one terrestrially-based station such that the at least one terrestrially-based station reuses frequencies assigned to satellite coverage areas adjoining the first satellite coverage area in the terrestrial coverage area based on relative geographical separation between the terrestrial coverage area and the respective adjoining satellite coverage areas.