Intra-system and/or inter-system reuse of feeder link frequencies including interference suppression systems and methods

• US 20060276129A1
• Filed: 03/14/2006
• Published: 12/07/2006
• Est. Priority Date: 03/15/2005
• Status: Active Grant

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: ATC Technology Corporation (FedEx Corporation)
• Inventors: Karabinis, Peter D.
• Granted Patent: US 7,634,229 B2
• Time in Patent Office: Days
• US Class Current: 455/13.300
• CPC Class Codes: H04B 7/1851 Systems using a satellite or space-based relay H04B7/18508, H04B7/18521 take precedence; providing specific services H04B7/18523 - H04B7/18576
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system

Abstract

Methods of reducing interference in a satellite communications system may include receiving a plurality of feeder link signals and time aligning the plurality of feeder link signals to provide time aligned feeder link signals. At least two of the time aligned feeder link signals may be combined to provide reduced interference of at least one of the feeder link signals. Related systems are also discussed.

Claims

1. A method of reducing interference in a satellite communications system, the method comprising:

receiving a plurality of feeder link signals; and

combining at least two of the plurality of feeder link signals to reduce interference in at least one of the feeder link signals.

2. A method according to claim 1 wherein receiving a plurality of feeder link signals comprises receiving a plurality of feeder link signals at a respective plurality of feeder link antenna elements of a Ground-Based Equipment (GBE).

3. A method according to claim 2 wherein receiving a plurality of feeder link signals comprises receiving a plurality of feeder link signals from a single source.

4. A method according to claim 2 wherein receiving a plurality of feeder link signals comprises receiving a plurality of feeder link signals from a plurality of sources.

5. A method according to claim 1 further comprising:

processing at least one first feeder link signal to time align the at least one first feeder link signal with at least one second feeder link signal.

6. A method according to claim 5 wherein processing at least one first feeder link signal comprises processing a first feeder link signal using a first delay circuit.

7. A method according to claim 6 wherein processing at least one first feeder link signal also comprises processing a second feeder link signal using a second delay circuit.

8. A method according to claim 7 wherein at least one of the first and second feeder link signals includes timing information, the method further comprising:

detecting the timing information and setting at least one delay value of the first and/or second delay circuits responsive to the detected timing information.

14. A method according to claim 1 wherein receiving a plurality of feeder link signals comprises receiving a plurality of feeder link signals at a respective plurality of feeder link antenna elements of a Space-Based Component (SBC).

9. A method of reducing interference in a satellite communications system, the method comprising:

determining an error of a received feeder link signal;

pre-distorting a signal responsive to the error; and

transmitting the pre-distorted signal.

10. A method according to claim 9 wherein pre-distorting a signal responsive to the error comprises combining a measure of the signal with a measure of at least one other signal that is correlated with the error.

11. A method according to claim 10 wherein the at least one other signal is a feeder link signal.

12. A method according to claim 11 wherein pre-distorting a signal responsive to the error comprises pre-distorting a feeder link signal, transmitting the pre-distorted signal comprises transmitting the pre-distorted signal to a Space-Based Component (SBC) and determining an error of a received feeder link signal comprises determining an error at the SBC.

15. A method according to claim 9 wherein the received feeder link signal includes an information component, and wherein determining an error of the received feeder link signal comprises comparing the information component with at least one value of the received feeder link signal.

16. A method according to claim 15 wherein the information component is compared with the at least one value at a Space-Based Component (SBC), and wherein a result of the comparison is transmitted from the SBC.

17. A method according to claim 15 wherein the information component is compared with the at least one value at a Ground-Based Equipment (GBE), and wherein a result of the comparison is transmitted from the GBE.

18. A method according to claim 15 wherein the information component comprises a-priori known information.

13. A method according to claim 111 wherein pre-distorting a signal responsive to the error comprises pre-distorting a feeder link signal, transmitting the pre-distorted signal comprises transmitting the pre-distorted signal to a Ground Based Equipment (GBE) and determining an error of a received feeder link signal comprises determining an error at the GBE.

19. A method of reducing interference in a satellite communications system, the method comprising:

providing first and second feeder link signals;

applying a weight to the second feeder link signal to provide a correction signal; and

combining the correction signal with the first feeder link signal to provide an interference reduced feeder link signal.

20. A method according to claim 19 further comprising:

applying a second weight to the first feeder link signal to provide a second correction signal; and

combining the second correction signal with the second feeder link signal to provide a second interference reduced feeder link signal.

21. A method according to claim 20 wherein the first and second feeder link signals are provided by at least one Space-Based Component (SBC).

22. A method according to claim 20 wherein the first and second feeder link signals are provided by at least one Ground-Based equipment (GBE).

23. A method according to claim 20 wherein the first and second feeder link signals are delay equalized therebetween.

24. A method according to claim 19 further comprising:

providing an error of a received feeder link signal;

wherein combining the correction signal with the first feeder link signal further comprises modifying the first and/or second feeder link signal(s) responsive to the error.

25. A method according to claim 24 wherein the received feeder link signal includes an information component, and wherein providing an error of a received feeder link signal comprises comparing the information component with at least one value of the received feeder link signal.

26. A method according to claim 25 wherein the information component is compared with the at least one value of the received feeder link signal at a Space-Based Component (SBC).

27. A method according to claim 25 wherein the information component is compared with the at least one value of the received feeder link signal at a Ground-Based Equipment (GBE).

28. A method according to claim 25 wherein the information component comprises a-priori known information.

29. A method of reducing interference in a satellite communications system, the method comprising:

providing an error of a received feeder link signal;

providing first and second feeder link signals;

calculating a weight based on the error;

applying the weight to the second feeder link signal to provide an error correction signal; and

combining the error correction signal with a component of the first feeder link signal to provide an interference reduced feeder link signal.

30. A method according to claim 29 wherein the received feeder link signal is received at a Space-Based Component (SBC) or at a Ground-Based Equipment (GBE).

31. A method according to claim 30 further comprising:

calculating a second weight;

applying the second weight to the first feeder link signal to provide a second error correction signal; and

combining the second error correction signal with a component of the second feeder link signal to provide a second interference reduced feeder link signal.

32. A method according to claim 31 wherein the first and second feeder link signals are provided by a Space-Based component (SBC) and/or by a Ground-Based equipment (GBE).

33. A method according to claim 31 wherein the interference reduced feeder link signal and/or the second interference reduced signal is/are transmitted to/by a Space-Based Component (SBC) or a Ground-Based Equipment (GBE).

34. A method according to claim 31 wherein the combining takes place at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE).

35. A method according to claim 30 wherein the received feeder link signal includes an information component, and wherein providing an error of a received feeder link signal comprises comparing the information component with at least one value of the received feeder link signal.

36. A method according to claim 35 wherein the comparing is performed at a Space-Based Component (SBC) and/or at a Ground-Based equipment (GBE).

37. A method according to claim 36 wherein a result of the comparing is transmitted to a Space-Based Component (SBC) and/or to a Ground-Based equipment (GBE).

38. A method according to claim 35 wherein the information component comprises a-priori known information.

39. A satellite communications system comprising:

a processor configured to combine at least two feeder link signals to provide at least one reduced interference feeder link signal.

40. A satellite communications system according to claim 39 wherein measures of the at least two feeder link signals are received at the processor from at least one Space-Based Component (SBC) and/or Ground-Based Equipment (GBE).

41. A satellite communications system according to claim 40 wherein the measures are received at the processor over spatially diverse paths and/or antenna patterns.

42. A satellite communications system according to claim 40 wherein the processor is at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE).

43. A satellite communications system according to claim 39 wherein the processor is further configured to time align the at least two feeder link signals prior to combining thereof.

44. A satellite communications system according to claim 43 wherein the processor is configured to time align the at least two feeder link signals by processing a first one of the at least two feeder link signals through a delay circuit.

45. A satellite communications system according to claim 44 wherein the processor is further configured to time align the at least two feeder link signals by processing a second one of the at least two feeder link signals through a second delay circuit.

46. A satellite communications system according to claim 45 wherein at least one of the at least two feeder link signals includes timing information, and wherein the processor is further configured to detect the timing information and to provide a time alignment responsive to the timing information.

47. A satellite communications system comprising:

a processor configured to provide an error of a feeder link signal; and

an interference reducer configured to reduce interference of the feeder link signal responsive to the error.

48. A satellite communications system according to claim 47 wherein the interference reducer is further configured to calculate a weight to be applied to a second feeder link signal to provide an error correction signal, and to combine the error correction signal with a measure of the feeder link signal.

49. A satellite communications system according to claim 48 wherein the feeder link signal and the second feeder link signal are received via spatially diverse paths and/or different antenna patterns.

50. A satellite communications system according to claim 48 wherein the processor is further configured to provide a second error of a second feeder link signal, and the interference reducer is further configured to calculate a second weight to be applied to the feeder link signal to provide a second error correction signal and to combine the second error correction signal with a measure of the second feeder link signal.

51. A satellite communications system according to claim 50 wherein the feeder link signal and the second feeder link signal are transmitted via spatially diverse paths and/or different antenna patterns.

52. A satellite communications system according to claim 50 wherein the processor and/or the interference reducer is/are at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE).

53. A satellite communications system according to claim 47 wherein the feeder link signal includes an information component, and wherein providing the error of the feeder link signal comprises comparing the information component with at least one value of the feeder link signal.

54. A satellite communications system according to claim 53 wherein the information component is compared with the at least one value at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE).

55. A satellite communications system according to claim 54 wherein a result of the comparison is transmitted to a Space-Based Component (SBC) and/or to a Ground-Based Equipment (GBE).

56. A satellite communications system according to claim 53 wherein the information component comprises a-priori known information.

57. A satellite communications system comprising:

a processor configured to apply a weight to a second feeder link signal to provide an error correction signal, and to combine the error correction signal with a first feeder link signal to provide an interference reduced feeder link signal.

58. A satellite communications system according to claim 57 wherein the processor is further configured to apply a second weight to the first feeder link signal to provide a second error correction signal, and to combine the second error correction signal with the second feeder link signal to provide a second interference reduced feeder link signal.

59. A satellite communications system according to claim 58 wherein the first and second feeder link signals are provided to the processor by spatially diverse paths and/or different antenna patterns.

60. A satellite communications system according to claim 58 wherein the interference reduced feeder link signal and/or the second interference reduced feeder link signal is/are provided at a system component that is spatially distant from and/or spatially proximate to the processor.

61. A satellite communications system according to claim 60 wherein the system component that is spatially distant from the processor is a Space-Based Component (SBC) and/or a Ground-Based Equipment (GBE) and/or wherein the system component that is spatially proximate to the processor is a SBC and/or a GBE.

62. A satellite communications system according to claim 57 wherein the processor is further configured to process an error of a feeder link signal and to provide at least one interference reduced feeder link signal responsive to the processing of the error.

63. A satellite communications system according to claim 62 wherein the feeder link signal includes an information component, wherein the information component is used to derive the error by comparing the information component with at least one value of the feeder link signal.

64. A satellite communications system according to claim 63 wherein the error is derived at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE) and/or is transmitted to the SBC and/or to the GBE.

65. A satellite communications system according to claim 63 wherein the error is derived at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE) and is used at the SBC and/or to the GBE.

66. A satellite communications system according to claim 63 wherein the information component comprises a-priori known information.

67. A satellite communications system comprising:

a processor configured to process an error of a feeder link signal, to process first and second feeder link signals, to calculate a weight to be applied to the second feeder link signal based on the error, to apply the weight to the second feeder link signal to provide an error correction signal, and to combine the error correction signal with a component of the first feeder link signal to provide a first interference reduced signal.

68. A satellite communications system according to claim 67 wherein the processor is at a Space-Based Component (SBC) and/or at a Ground-Based equipment (GBE).

69. A satellite communications system according to claim 68 wherein the processor is further configured to calculate a second weight to be applied to the first feeder link signal to provide a second error correction signal, and to combine the second error correction signal with a component of the second feeder link signal to provide a second interference reduced signal.

70. A satellite communications system according to claim 69 wherein the first and second feeder link signals are provided to the processor via spatially diverse paths and/or different antenna patterns.

71. A satellite communications system according to claim 69 wherein the first and second interference reduced signals are provided by the processor over spatially diverse paths and/or different antenna patterns.

72. A satellite communications system according to claim 69 wherein the first and/or second interference reduced signals are provided by the processor to a Space-Based Component (SBC) and/or to a Ground-Based equipment (GBE).

73. A satellite communications system according to claim 68 wherein the feeder link signal includes an information component that is used to derive the error by comparing the information component with at least one value of the feeder link signal.

74. A satellite communications system according to claim 73 wherein the comparing is performed at a Space-Based Component (SBC) and/or at a Ground-Based Equipment (GBE).

75. A satellite communications system according to claim 74 wherein a result of the comparing is transmitted to a Space-Based Component (SBC) and/or to a Ground-Based Equipment (GBE).

76. A satellite communications system according to claim 73 wherein the information component comprises a-priori known information.