Spatial guardbands for terrestrial reuse of satellite frequencies

• US 20030054761A1
• Filed: 06/26/2002
• Published: 03/20/2003
• Est. Priority Date: 09/14/2001
• Status: Active Grant

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: ATC Technology Corporation (FedEx Corporation)
• Inventors: Karabinis, Peter D.
• Granted Patent: US 6,999,720 B2
• Time in Patent Office: Days
• US Class Current: 455/12.1
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18543 for adaptation of transmission parameters, e.g. power control for detecting or preventing errors in the information received H04L1/00
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning

Abstract

Satellite radiotelephone systems include a space-based component that is configured to provide wireless radiotelephone communications in a satellite footprint over a satellite radiotelephone frequency band. The satellite footprint is divided into a plurality of satellite cells, in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused. An ancillary terrestrial network is configured to terrestrially reuse at least one of the ancillary radiotelephone frequencies that is used in a satellite cell in the satellite footprint, outside the cell and in some embodiments separated therefrom by a spatial guardband. The spatial guardband may be sufficiently large to reduce or prevent interference between the at least one of the satellite radiotelephone frequencies that is used in the satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the satellite cell and separated therefrom by the spatial guardband. The spatial guardband may be about half a radius of a satellite cell in width.

Claims

1. A satellite radiotelephone system comprising:

a space-based component that is configured to provide wireless radiotelephone communications in a satellite footprint over a satellite radiotelephone frequency band, the satellite footprint being divided into a plurality of satellite cells in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused; and

an ancillary terrestrial network that is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell.

2. A satellite radiotelephone system according to claim 1 wherein the ancillary terrestrial network is further configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by a spatial guardband.

3. A satellite radiotelephone system according to claim 2 wherein the spatial guardband is sufficiently large to reduce interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

4. A satellite radiotelephone system according to claim 2 wherein the spatial guardband is sufficiently large to prevent interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

5. A satellite radiotelephone system according to claim 2 wherein the ancillary terrestrial network is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

6. A satellite radiotelephone system according to claim 2 wherein the ancillary terrestrial network is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separate therefrom by the spatial guardband.

7. A satellite radiotelephone system according to claim 2 wherein the ancillary terrestrial network is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

8. A satellite radiotelephone system according to claim 2 wherein the ancillary terrestrial network is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

9. A satellite radiotelephone system according to claim 2 wherein the spatial guardband is about half a radius of a satellite cell in width.

10. A satellite radiotelephone system according to claim 1 further comprising:

an interference reducer that is responsive to the space-based component and to the ancillary terrestrial network, and that is configured to reduce interference from wireless communications that are received by the space-based component from a first radiotelephone in the satellite footprint over the satellite radiotelephone frequency band, using wireless communications that are received by the ancillary terrestrial network from a second radiotelephone in the satellite footprint over the satellite radiotelephone frequency band.

11. A satellite radiotelephone system according to claim 2:

wherein the ancillary terrestrial network is divided into a plurality of ancillary terrestrial network cells in which frequencies of the satellite radiotelephone frequency band are spatially reused and is further configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, in ancillary terrestrial network cells that are outside the predetermined satellite cell and separated therefrom by the spatial guardband.

12. A satellite radiotelephone system according to claim 2:

wherein the ancillary terrestrial network is further configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, by not terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, within the predetermined satellite cell or within the spatial guardband.

13. A satellite radiotelephone system according to claim 2 wherein the ancillary terrestrial network comprises a plurality of ancillary terrestrial components, at least a first one of which is located in the predetermined satellite cell and is configured not to terrestrially reuse the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell for satellite communications, and at least a second one of which is located outside the predetermined satellite cell and separated therefrom by the spatial guardband and is configured to terrestrially reuse the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell for satellite communications.

14. A satellite radiotelephone system according to claim 1 in combination with a plurality of radiotelephones that are configured to wirelessly communicate with the space-based component and/or the ancillary terrestrial network.

15. A satellite radiotelephone system according to claim 2 wherein the ancillary terrestrial network is further configured to determine portions thereof that are located outside the predetermined satellite cell and separated therefrom by the spatial guardband.

16. A satellite radiotelephone system according to claim 15 wherein the ancillary terrestrial network is further configured to determine whether portions thereof are located outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving and/or processing at least one of the satellite radiotelephone frequencies of the satellite radiotelephone frequency band.

17. A satellite radiotelephone system according to claim 15 wherein the satellite radiotelephone frequencies include a plurality of Broadcast Control CHannel (BCCH) frequencies and wherein the ancillary terrestrial network is further configured to determine portions thereof that are located outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving and/or processing signal strength and/or content of at least one of the BCCH frequencies.

18. A satellite radiotelephone system according to claim 15 wherein the ancillary terrestrial network comprises a plurality of ancillary terrestrial components, each of which is configured to determine whether it is located outside the predetermined satellite cell and separated therefrom by the spatial guardband.

19. A satellite radiotelephone system according to claim 15 wherein the ancillary terrestrial network comprises a plurality of ancillary terrestrial components, at least one of which is configured to determine whether it is located outside the predetermined satellite cell and separated therefrom by the spatial guardband and to transmit results of the determination to at least a second one of the plurality of ancillary terrestrial components.

20. An ancillary terrestrial component for a satellite radiotelephone system that includes a space-based component that is configured to provide wireless radiotelephone communications in a satellite footprint over a satellite radiotelephone frequency band, the satellite footprint being divided into a plurality of satellite cells in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused, the ancillary terrestrial component comprising:

an electronics system that is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in at least one predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located outside the at least one predetermined satellite cell and not to terrestrially reuse the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located within the predetermined satellite cell.

21. An ancillary terrestrial component according to claim 20 wherein the electronics system is further configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in at least one predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located outside the at least one predetermined satellite cell an separated therefrom by a spatial guardband and not to terrestrially reuse the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located within the predetermined satellite cell or within the spatial guardband.

22. An ancillary terrestrial component according to claim 21 wherein the spatial guardband is sufficiently large to reduce interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

23. An ancillary terrestrial component according to claim 21 wherein the spatial guardband is sufficiently large to prevent interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

24. An ancillary terrestrial component according to claim 21 wherein the ancillary terrestrial component is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

25. An ancillary terrestrial component according to claim 21 wherein the ancillary terrestrial component is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

26. An ancillary terrestrial component according to claim 21 wherein the ancillary terrestrial component is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

27. An ancillary terrestrial component according to claim 21 wherein the ancillary terrestrial component is configured to terrestrially reuse at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband by transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

28. An ancillary terrestrial component according to claim 21 wherein the spatial guardband is about half a radius of a satellite cell in width.

29. An ancillary terrestrial component according to claim 20 in combination with a plurality of radiotelephones that are configured to wirelessly communicate with the space-based component and/or the ancillary terrestrial component.

30. An ancillary terrestrial component according to claim 21 wherein the ancillary terrestrial component is further configured to determine whether the ancillary terrestrial component is located outside the predetermined satellite cell and separated therefrom by the spatial guardband.

31. An ancillary terrestrial component according to claim 30 wherein the ancillary terrestrial component is further configured to determine whether the ancillary terrestrial component is located outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving and/or processing at least one of the satellite radiotelephone frequencies of the satellite radiotelephone frequency band.

32. An ancillary terrestrial component according to claim 30 wherein the satellite radiotelephone frequencies include a plurality of Broadcast Control CHannel (BCCH) frequencies and wherein the ancillary terrestrial component is further configured to determine whether the ancillary terrestrial component is located outside the predetermined satellite cell and separated therefrom by the spatial guardband by receiving and/or processing signal strength and/or content of at least one of the BCCH frequencies.

33. An ancillary terrestrial component according to claim 30 wherein the ancillary terrestrial component is configured to determine whether it is located outside the predetermined satellite cell and separated therefrom by the spatial guardband and to transmit results of the determination to at least a second ancillary terrestrial component.

34. A satellite radiotelephone communications method comprising:

providing space-based wireless radiotelephone communications in a satellite footprint over a satellite radiotelephone frequency band, the satellite footprint being divided into a plurality of satellite cells in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused; and

terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell.

35. A satellite radiotelephone communications method according to claim 34 wherein the terrestrially reusing comprises:

terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by a spatial guardband.

36. A satellite radiotelephone communications method according to claim 35 wherein the spatial guardband is sufficiently large to reduce interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

37. A satellite radiotelephone communications method according to claim 35 wherein the spatial guardband is sufficiently large to prevent interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

38. A satellite radiotelephone communications method according to claim 35 wherein the terrestrially reusing comprises receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

39. A satellite radiotelephone communications method according to claim 35 wherein the terrestrially reusing comprises receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

40. A satellite radiotelephone communications method according to claim 35 wherein the terrestrially reusing comprises transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

41. A satellite radiotelephone communications method according to claim 35 wherein the terrestrially reusing comprises transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

42. A satellite radiotelephone communications method according to claim 35 wherein the spatial guardband is about half a radius of a satellite cell in width.

43. A satellite radiotelephone communications method according to claim 34 further comprising:

reducing interference from space-based wireless communications that are received from a first radiotelephone in the satellite footprint over the satellite radiotelephone frequency band, using wireless communications that are received terrestrially from a second radiotelephone in the satellite footprint over the satellite radiotelephone frequency band.

44. A satellite radiotelephone communications method according to claim 35 further comprising:

refraining from terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, within the predetermined satellite cell or within the spatial guardband.

45. A satellite radiotelephone communications method according to claim 35 further comprising determining where to terrestrially reuse the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint.

46. A satellite radiotelephone communications method according to claim 45 wherein the determining comprises receiving and/or processing at least one of the satellite radiotelephone frequencies of the satellite radiotelephone frequency band.

47. A satellite radiotelephone communications method according to claim 45 wherein the satellite radiotelephone frequencies include a plurality of Broadcast Control CHannel (BCCH) frequencies and wherein the determining comprises receiving and/or processing signal strength and/or content of at least one of the BCCH frequencies.

48. A satellite radiotelephone system according to claim 45 further comprising transmitting results of the determining.

49. A satellite radiotelephone system comprising:

means for providing space-based wireless radiotelephone communications in a satellite footprint over a satellite radiotelephone frequency band, the satellite footprint being divided into a plurality of satellite cells in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused; and

means for terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell.

50. A satellite radiotelephone system according to claim 49 wherein the means for terrestrially reusing comprises:

means for terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by a spatial guardband.

51. A satellite radiotelephone system according to claim 50 wherein the spatial guardband is sufficiently large to reduce interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

52. A satellite radiotelephone system according to claim 50 wherein the spatial guardband is sufficiently large to prevent interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

53. A satellite radiotelephone system according to claim 50 wherein the means for terrestrially reusing comprises means for receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

54. A satellite radiotelephone system according to claim 50 wherein the means for terrestrially reusing comprises means for receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the means for providing in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

55. A satellite radiotelephone system according to claim 50 wherein the means for terrestrially reusing comprises means for transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

56. A satellite radiotelephone system according to claim 50 wherein the means for terrestrially reusing comprises means for transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the means for providing in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

57. A satellite radiotelephone system according to claim 50 wherein the spatial guardband is about half a radius of a satellite cell in width.

58. A satellite radiotelephone system according to claim 49 further comprising:

means for reducing interference from space-based wireless communications that are received from a first radiotelephone in the satellite footprint over the satellite radiotelephone frequency band, using wireless communications that are received terrestrially from a second radiotelephone in the satellite footprint over the satellite radiotelephone frequency band.

59. A satellite radiotelephone system according to claim 50:

wherein the means for terrestrially reusing comprises;

a plurality of ancillary terrestrial network cells in which frequencies of the satellite radiotelephone frequency band are spatially reused; and

means for terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint, in ancillary terrestrial network cells that are outside the predetermined satellite cell and separated therefrom by the spatial guardband.

60. A satellite radiotelephone system according to claim 50:

wherein the means for terrestrially reusing further comprises means for refraining from terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint for satellite communications, within the predetermined satellite cell or within the spatial guardband.

61. A satellite radiotelephone system according to claim 50 wherein the means for terrestrially reusing comprises a plurality of ancillary terrestrial components, at least a first one of which is located in the predetermined satellite cell and comprises means for refraining from terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell for satellite communications, and at least a second one of which is located outside the predetermined satellite cell and separated therefrom by the spatial guardband and comprises means for terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell for satellite communications.

62. A satellite radiotelephone system according to claim 49 in combination with a plurality of radiotelephones that are configured to wirelessly communicate therewith in space-based and/or the terrestrial modes.

63. A satellite radiotelephone system according to claim 49 wherein the means for terrestrially reusing comprises means for determining where to terrestrially reuse the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint.

64. A satellite radiotelephone system according to claim 63 wherein the means for determining comprises means for receiving and/or processing at least one of the satellite radiotelephone frequencies of the satellite radiotelephone frequency band.

65. A satellite radiotelephone system according to claim 63 wherein the satellite radiotelephone frequencies include a plurality of Broadcast Control CHannel (BCCH) frequencies and wherein the means for determining comprises means for receiving and/or processing signal strength and/or content of at least one of the BCCH frequencies.

66. A satellite radiotelephone system according to claim 63 wherein the means for terrestrially reusing comprises a plurality of ancillary terrestrial components, each of which comprises means for determining whether it is located outside the predetermined satellite cell and separated therefrom by the spatial guardband.

67. A satellite radiotelephone system according to claim 63 wherein the means for terrestrially reusing comprises a plurality of ancillary terrestrial components, at least one of which comprises means for determining whether it is located outside the predetermined satellite cell and separated therefrom by the spatial guardband and means for transmitting results of the means for determining to at least a second one of the plurality of ancillary terrestrial components.

68. An ancillary terrestrial component for a satellite radiotelephone system that includes a space-based component that is configured to provide wireless radiotelephone communications in a satellite footprint over a satellite radiotelephone frequency band, the satellite footprint being divided into a plurality of satellite cells in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused, the ancillary terrestrial component comprising:

means for terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located outside the predetermined satellite cell; and

means for refraining from terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located within the predetermined satellite cell.

69. An ancillary terrestrial component according to claim 68:

wherein the means for terrestrially reusing comprises means for terrestrially reusing at least one of the satellite radiotelephone frequencies that is used in a predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located outside the predetermined satellite cell and separated from therefrom by a spatial guardband; and

wherein the means for refraining from terrestrially reusing comprises means for refraining from terrestrially reusing the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint when the ancillary terrestrial component is located within the predetermined satellite cell or within the spatial guardband.

70. An ancillary terrestrial component according to claim 69 wherein the spatial guardband is sufficiently large to reduce interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

71. An ancillary terrestrial component according to claim 69 wherein the spatial guardband is sufficiently large to prevent interference between the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, and the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the predetermined satellite cell and separated therefrom by the spatial guardband.

72. An ancillary terrestrial component according to claim 69 wherein the means for terrestrially reusing comprises means for receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

73. An ancillary terrestrial component according to claim 69 wherein the means for terrestrially reusing comprises means for receiving the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

74. An ancillary terrestrial component according to claim 69 wherein the means for terrestrially reusing comprises means for transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

75. An ancillary terrestrial component according to claim 69 wherein the means for terrestrially reusing comprises means for transmitting the at least one of the satellite radiotelephone frequencies that is used in the predetermined satellite cell in the satellite footprint and at least one other frequency that is used by the space-based component in the satellite footprint, outside the predetermined satellite cell and separated therefrom by the spatial guardband.

76. An ancillary terrestrial component according to claim 69 wherein the spatial guardband is about half a radius of a satellite cell in width.

77. An ancillary terrestrial component according to claim 68 in combination with a plurality of radiotelephones that are configured to wirelessly communicate with the space-based component and/or the ancillary terrestrial component.

78. An ancillary terrestrial component according to claim 69 wherein the ancillary terrestrial component further comprises means for determining whether the ancillary terrestrial component is located outside the predetermined satellite cell and separated therefrom by the spatial guardband.

79. An ancillary terrestrial component according to claim 78 wherein the means for determining comprises means for receiving and/or processing of at least one of the satellite radiotelephone frequencies of the satellite radiotelephone frequency band.

80. An ancillary terrestrial component according to claim 78 wherein the satellite radiotelephone frequencies include a plurality of Broadcast Control CHannel (BCCH) frequencies and wherein the means for determining comprises means for receiving and/or processing signal strength and/or content of at least one of the BCCH frequencies.

81. An ancillary terrestrial component according to claim 78 further comprising means for transmitting results of the means for determining to at least a second ancillary terrestrial component.