Satellite with different size service link antennas and radioterminal communication methods using same

• US 8,380,186 B2
• Filed: 01/14/2005
• Issued: 02/19/2013
• Est. Priority Date: 01/22/2004
• Status: Expired due to Fees

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: ATC Technology Corporation (FedEx Corporation)
• Inventors: Karabinis, Peter D.
• Primary Examiner(s): Karikari, Kwasi
• Application Number:
  US11/036,230
• Publication Number:
  US 20050164700A1
• Time in Patent Office: 2,958 Days
• Field of Search: 455/427, 455/430, 455/429, 455/12.1, 455/431, 455/16, 455/13.2, 455/13.3, 455/13.1
• US Class Current: 455/427
• CPC Class Codes: H04B 7/1853 Satellite systems for providing telephony service to a mobile station, i.e. mobile satellite service for selecting H04W
• CPC Class Codes: H04B 7/2041 Spot beam multiple access

Abstract

A space segment for a radioterminal communications system includes a satellite having service link antennas of different sizes that are configured to communicate with at least one radioterminal. The service link antennas of different size may serve different sized geographic areas, which may at least partially overlap. Analogous radioterminal communications methods also are provided.

Claims

1. A space segment for a radioterminal communications system comprising:

a satellite including service link antennas of different sizes, each of said service link antennas being configured to communicate with at least one radioterminal, at least one of the service link antennas being configured to receive both Left Hand Circularly Polarized (LHCP) radiation and Right Hand Circularly Polarized (RHCP) radiation,

wherein a gain-to-temperature ratio (G/T) of the at least one of the service link antennas that is configured to receive both LHCP radiation and RHCP radiation comprises a value of 21 dB/K.

2. The system according to claim 1 wherein the service link antennas of different sizes comprise:

a first service link antenna; and

a second service link antenna that is smaller than the first service link antenna;

wherein the G/T of the first service link antenna comprises a value of 21 dB/K and the G/T of the second service link antenna comprises a value of 9 dB/K.

3. The system according to claim 2 wherein the first service link antenna is configured to serve a first geographic area and wherein the second service link antenna is configured to serve a second geographic area that is larger than the first geographic area.

4. The system according to claim 3 wherein the first geographic area is geographically distinct from, geographically overlaps with, or is geographically contained within the second geographic area.

5. The system according to claim 3 wherein the first service link antenna is configured to form smaller, higher gain satellite beams than the second service link antenna.

6. The system according to claim 5 wherein the first service link antenna includes more radiators than the second service link antenna.

7. The system according to claim 2 wherein the first service link antenna is configured to receive both LHCP radiation and RHCP radiation and wherein the second service link antenna is configured to receive only LHCP or RHCP radiation.

8. The system according to claim 2 wherein the first and second service link antennas comprise reflectors.

9. The system according to claim 2 wherein the satellite further comprises a signal processing equipment for the second service link antenna and is free of the signal processing equipment for the first service link antenna.

10. The system according to claim 2 wherein the satellite further comprises a signal processing equipment for a forward link of the first and/or second service link antennas and is free of the signal processing equipment for a return link of the first and/or second service link antennas.

11. The system according to claim 9 wherein the signal processing equipment comprises beam forming and/or channelization equipment.

12. The system according to claim 10 wherein the signal processing equipment comprises beam forming and/or channelization equipment.

61. The system according to claim 1 wherein a beam forming processor that is associated with the at least one of the service link antennas is positioned remote from the satellite and is distributed between at least two gateways of the satellite.

13. A radioterminal communications method comprising:

communicating between a satellite and at least one radioterminal over a plurality of service links using a plurality of service link antennas of different sizes, wherein at least one of the service link antennas is configured to receive both Left Hand Circularly Polarized (LHCP) radiation and Right Hand Circularly Polarized (RHCP) radiation and wherein a gain-to-temperature ratio (G/T) of the at least one of the service link antennas that is configured to receive both LHCP radiation and RHCP radiation comprises a value of 21 dB/K.

14. The method according to claim 13 wherein the service link antennas of different sizes comprise:

a first service link antenna; and

a second service link antenna that is smaller than the first service link antenna;

wherein the G/T of the first service link antenna comprises a value of 21 dB/K and the G/T of the second service link antenna comprises a value of 9 dB/K.

15. The method according to claim 14 wherein communicating comprises:

communicating between the satellite and at least one radioterminal in a first geographic area using the first service link antenna; and

communicating between the satellite and at least one radioterminal in a second geographic area that is larger than the first geographic area, using the second service link antenna.

16. The method according to claim 15 wherein the first geographic area is geographically distinct from, geographically overlaps with, or is geographically contained within the second geographic area.

17. The method according to claim 15 further comprising:

forming smaller, higher gain satellite beams by the first service link antenna than by the second service link antenna.

18. The method according to claim 17 wherein the first service link antenna includes more radiators than the second service link antenna.

19. The method according to claim 14 further comprising:

receiving both LHCP radiation and RHCP radiation at the first service link antenna; and

receiving only LHCP or RHCP radiation at the second service link antenna.

20. The method according to claim 14 wherein the first and second service link antennas comprise reflectors.

21. The method according to claim 14 further comprising:

processing signals associated with the second service link antenna on-board the satellite; and

processing signals associated with the first service link antenna external to the satellite.

22. The method according to claim 14 further comprising:

processing signals associated with a forward link for the first and/or second service link antennas on-board the satellite; and

processing signals associated with a return link for the first and/or second service link antennas external to the satellite.

23. The method according to claim 21 wherein processing signals comprises beam forming and/or channelizing.

24. The method according to claim 22 wherein processing signals comprises beam forming and/or channelizing.

62. The method according to claim 13 wherein a beam forming processor that is associated with the at least one of the service link antennas is positioned remote from the satellite and is distributed between at least two gateways of the satellite.

25. A space segment for a radioterminal communications system comprising:

a satellite comprising first and second service link antennas, wherein the first service link antenna is configured to receive both Left Hand Circularly Polarized (LHCP) radiation and Right Hand Circularly Polarized (RHCP) radiation and wherein the second service link antenna is configured to receive only LHCP or RHCP radiation, and

wherein a gain-to-temperature ratio (G/T) of said first service link antenna that is configured to receive both LHCP radiation and RHCP radiation comprises a value of 21 dB/K.

26. The system according to claim 25 wherein the first service link antenna is configured to form smaller, higher gain satellite beams than the second service link antenna, and wherein the G/T of the first service link antenna comprises a value of 21 dB/K and the G/T of the second service link antenna comprises a value of 9 dB/K.

27. The system according to claim 26 wherein the first service link antenna includes more radiators than the second service link antenna.

28. The system according to claim 25 wherein the satellite further comprises a signal processing equipment for the second service link antenna and is free of the signal processing equipment for the first service link antenna.

29. The system according to claim 25 wherein the satellite further comprises a signal processing equipment for a forward link of the first and/or second service link antennas and is free of the signal processing equipment for a return link of the first and/or second service link antennas.

30. The system according to claim 28 wherein the signal processing equipment comprises beam forming and/or channelization equipment.

31. The system according to claim 29 wherein the signal processing equipment comprises beam forming and/or channelization equipment.

63. The system according to claim 25 wherein a beam forming processor that is associated with the first service link antenna is positioned remote from the satellite and is distributed between at least two gateways of the satellite.

32. A radioterminal communications method comprising:

communicating between a satellite and at least one radioterminal over a plurality of service links using first and second service link antennas, wherein communicating comprises;

receiving both Left Hand Circularly Polarized (LHCP) radiation and Right Hand Circularly Polarized (RHCP) radiation at the first service link antenna; and

receiving only LHCP or RHCP radiation at the second service link antenna, and

wherein a gain-to-temperature ratio (G/T) of said first service link antenna that receives both LHCP radiation and RHCP radiation comprises a value of 21 dB/K.

33. The method according to claim 32 further comprising:

forming smaller, higher gain satellite beams by the first service link antenna than by the second service link antenna, wherein the G/T of the first service link antenna comprises a value of 21 dB/K and the G/T of the second service link antenna comprises a value of 9 dB/K.

34. The method according to claim 33 wherein the first service link antenna includes more radiators than the second service link antenna.

35. The method according to claim 32 further comprising:

processing signals associated with the second service link antenna on-board the satellite; and

processing signals associated with the first service link antenna external to the satellite.

36. The method according to claim 32 further comprising:

processing signals associated with a forward link for the first and/or second service link antennas on-board the satellite; and

processing signals associated with a return link for the first and/or second service link antennas external to the satellite.

37. The method according to claim 35 wherein processing signals comprises beam forming and/or channelizing.

38. The method according to claim 36 wherein processing signals comprises beam forming and/or channelizing.

64. The method according to claim 32 wherein a beam forming processor that is associated with the first service link antenna is positioned remote from the satellite and is distributed between at least two gateways of the satellite.

39. A space segment for a radioterminal communications system comprising:

a satellite comprising a first service link antenna configured to provide a first return service link and a first forward service link for communicating with at least one radioterminal and a second service link antenna that is smaller than the first service link antenna and configured to provide a second return service link and a second forward service link for communicating with at least one radioterminal;

wherein the satellite further comprises a signal processing equipment for at least one of the first return service link, the first forward service link, the second return service link and/or the second forward service link and is free of the signal processing equipment for at least another one of the first return service link, the first forward service link, the second return service link and/or the second forward service link, and

wherein a gain-to-temperature ratio (G/T) of said first service link antenna configured to provide a first return service link comprises a value of 21 dB/K.

40. The system according to claim 39 wherein the first service link antenna is configured to serve a first geographic area and wherein the second service link antenna is configured to serve a second geographic area that is larger than the first geographic area.

41. The system according to claim 40 wherein the first geographic area is geographically distinct from, geographically overlaps with, or is geographically contained within the second geographic area.

42. The system according to claim 40 wherein the first service link antenna is configured to form smaller, higher gain satellite beams than the second service link antenna, and wherein the G/T of the first service link antenna comprises a value of 21 dB/K and the G/T of the second service link antenna comprises a value of 9 dB/K.

43. The system according to claim 42 wherein the first service link antenna includes more radiators than the second service link antenna.

44. The system according to claim 39 wherein the first service link antenna is configured to receive both Left Hand Circularly Polarized (LHCP) radiation and Right Hand Circularly Polarized (RHCP) radiation and wherein the second service link antenna is configured to receive only LHCP or RHCP radiation.

45. The system according to claim 39 wherein the first and second service link antennas comprise reflectors.

46. The system according to claim 39 wherein the satellite further comprises a signal processing equipment for the second service link antenna and is free of the signal processing equipment for the first service link antenna.

47. The system according to claim 39 wherein the satellite further comprises a signal processing equipment for the first and/or second forward service links and is free of the signal processing equipment for the first and/or second return service links.

48. The system according to claim 46 wherein the signal processing equipment comprises beam forming and/or channelization equipment.

49. The system according to claim 47 wherein the signal processing equipment comprises beam forming and/or channelization equipment.

65. The system according to claim 39 wherein a beam forming processor that is associated with the first service link antenna is positioned remote from the satellite and is distributed between at least two gateways of the satellite.

50. A radioterminal communications method comprising:

communicating between a satellite and at least one radioterminal using a first service link antenna configured to provide a first return service link and a first forward service link and a second service link antenna that is smaller than the first service link antenna and configured to provide a second return service link and a second forward service link;

processing on-board the satellite, signals associated with at least one of the first return service link, the first forward service link, the second return service link and/or the second forward service link; and

processing external to the satellite, signals associated with at least another one of the first return service link, the first forward service link, the second return service link and/or the second forward service link, and

wherein a gain-to-temperature ratio (G/T) of said first service link antenna configured to provide a first return service link comprises a value of 21 dB/K.

51. The method according to claim 50 wherein communicating comprises:

communicating between the satellite and at least one radioterminal in a first geographic area using the first service link antenna; and

communicating between the satellite and at least one radioterminal in a second geographic area that is larger than the first geographic area, using the second service link antenna.

52. The method according to claim 51 wherein the first geographic area is geographically distinct from, geographically overlaps with, or is geographically contained within the second geographic area.

53. The method according to claim 50 further comprising:

forming smaller, higher gain satellite beams by the first service link antenna than by the second service link antenna.

54. The method according to claim 53 wherein the first service link antenna includes more radiators than the second service link antenna, and wherein the G/T of the first service link antenna comprises a value of 21 dB/K and the G/T of the second service link antenna comprises a value of 9 dB/K.

55. The method according to claim 50 further comprising:

receiving both Left Hand Circularly Polarized (LHCP) radiation and Right Hand Circularly Polarized (RHCP) radiation at the first service link antenna; and

receiving only LHCP or RHCP radiation at the second service link antenna.

56. The method according to claim 50 wherein the first and second service link antennas comprise reflectors.

57. The method according to claim 50:

wherein processing on-board the satellite comprises processing signals associated with the second service link antenna on-board the satellite; and

wherein processing external to the satellite comprises processing signals associated with the first service link antenna external to the satellite.

58. The method according to claim 50:

wherein processing on-board the satellite comprises processing signals associated with the first and/or second forward service links on-board the satellite; and

wherein processing external to the satellite comprises processing signals associated with the first and/or second return service links external to the satellite.

59. The method according to claim 57 wherein processing comprises beam forming and/or channelizing.

60. The method according to claim 58 wherein processing comprises beam forming and/or channelizing.

66. The method according to claim 50 wherein a beam forming processor that is associated with the first service link antenna is positioned remote from the satellite and is distributed between at least two gateways of the satellite.