SYSTEMS AND METHODS FOR TERRESTRIAL REUSE OF CELLULAR SATELLITE FREQUENCY SPECTRUM IN A TIME-DIVISION DUPLEX AND/OR FREQUENCY-DIVISION DUPLEX MODE

• US 20100039967A1
• Filed: 10/23/2009
• Published: 02/18/2010
• Est. Priority Date: 09/14/2001
• Status: Active Grant

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: ATC Technology Corporation (FedEx Corporation)
• Inventors: Churan, Gary G., Karabinis, Peter D.
• Granted Patent: US 8,078,101 B2
• Time in Patent Office: Days
• US Class Current: 370/294
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• 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 7/18563 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: H04Q 2213/13098 Mobile subscriber
• CPC Class Codes: H04Q 2213/13196 Connection circuit/link/trunk/junction, bridge, router, gateway
• CPC Class Codes: H04Q 2213/13292 Time division multiplexing, TDM
• CPC Class Codes: H04Q 2213/13333 Earth satellites
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range

Abstract

A space-based component, such as a satellite, is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency, and to transmit wireless communications to the radiotelephones over a downlink radiotelephone frequency. An ancillary terrestrial network, that may include one or more ancillary terrestrial components, is configured to transmit wireless communications to, and receive wireless communications from, the radiotelephones over the uplink satellite radiotelephone frequency in a time-division duplex mode. An interference reducer is configured to reduce interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or from the ancillary terrestrial network over the uplink satellite radiotelephone frequency, using the wireless communications that are transmitted by the ancillary terrestrial to, and/or received by the ancillary terrestrial network from, the second radiotelephone over the uplink satellite radiotelephone frequency.

Claims

1. A satellite radiotelephone system comprising:

a space-based component that is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency and to transmit wireless communications to radiotelephones over a downlink satellite radiotelephone frequency; and

a wireless terrestrial network that is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode.

2. A satellite radiotelephone system according to claim 1 wherein the wireless terrestrial network also is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over a downlink satellite radiotelephone frequency in a time-division duplex mode.

3. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first portion is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency and wherein at least a second portion is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency.

4. A satellite radiotelephone system according to claim 1 wherein the uplink satellite radiotelephone frequency comprises an uplink satellite radiotelephone frequency band and wherein the wireless terrestrial network is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over an uplink satellite radiotelephone frequency band in a time-division duplex mode.

5. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame including a plurality of slots, wherein a first portion of the transmit/receive time interval and/or frame and/or a first number of the slots is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency and wherein a second portion of the transmit/receive time interval and/or frame and/or a second number of the slots is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency.

6. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first portion thereof is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency using OFDM and/or OFDMA and M-ary QAM modulation and/or protocol and wherein at least a second portion thereof is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency using OFDM and/or OFDMA and L-ary QAM modulation and/or protocol wherein L≦

M, and L and M are greater than or equal to one.

7. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first one portion thereof is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency using a first modulation and/or protocol and wherein at least a second one portion thereof is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency using a second modulation and/or protocol, wherein the first modulation and/or protocol is more spectrally efficient than the second modulation and/or protocol.

8. A satellite radiotelephone system according to claim 1:

wherein the space-based component is configured to receive wireless communications from a first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band and to transmit wireless communications to the first radiotelephone in the satellite footprint over a downlink satellite radiotelephone frequency band;

wherein the wireless terrestrial network is configured to transmit wireless communications to, and receive wireless communications from, a second radiotelephone over an uplink satellite radiotelephone frequency band, the space-based component also receiving the wireless communications from the second radiotelephone and/or the wireless terrestrial network over an uplink satellite radiotelephone frequency band as interference along with the wireless communications that are received from the first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band; and

wherein the satellite radiotelephone system further comprises an interference reducer that is responsive to the space-based component and to the wireless terrestrial network, and that is configured to reduce the interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or the wireless terrestrial network over an uplink satellite radiotelephone frequency band, using the wireless communications that are transmitted by the wireless terrestrial network to, and/or received by the wireless terrestrial network from, the second radiotelephone over an uplink satellite radiotelephone frequency band.

9. A satellite radiotelephone system according to claim 8 wherein the wireless terrestrial network is closer to the second radiotelephone than to the space-based component such that the wireless communications from the second radiotelephone are received by the wireless terrestrial network and the wireless communications from the wireless terrestrial network to the second radiotelephone are generated by the wireless terrestrial network prior to reception by the space-based component and wherein the interference reducer is configured to generate at least one delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications from the wireless terrestrial network to the second radiotelephone, and to subtract a measure of the delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications from the wireless terrestrial network to the second radiotelephone, from the wireless communications that are received from the space-based component.

10. A satellite radiotelephone system according to claim 8 wherein the interference reducer comprises an adaptive interference reducer.

11. A satellite radiotelephone system according to claim 8 further comprising a gateway that communicates with the space-based component and with the wireless terrestrial network and wherein the interference reducer is at least partially included in the gateway.

12. A satellite radiotelephone system according to claim 8 wherein the interference reducer is at least partially included in the wireless terrestrial network.

13. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode contains a sequence of transmit/receive intervals and wherein one first transmit/receive interval is different from one second transmit/receive interval.

14. A satellite radiotelephone system according to claim 13 wherein one first transmit/receive interval is different from one second transmit/receive interval in modulation, protocol and/or time duration.

15. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode contains a sequence of transmit/receive intervals and wherein one first transmit/receive interval is the same or substantially the same to one second transmit/receive interval in modulation, protocol, and/or time duration.

16. A satellite radiotelephone system according to claim 1 wherein the time-division duplex mode contains a sequence of identical or substantially identical transmit/receive intervals in modulation, protocol and/or time duration.

17. A wireless terrestrial component for a satellite radiotelephone system that includes a space-based component that is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency and to transmit wireless communications to radiotelephones over a downlink satellite radiotelephone frequency, the wireless terrestrial component comprising:

an electronics system that is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode.

18. A wireless terrestrial component according to claim 17 wherein the electronics system also is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over a downlink satellite radiotelephone frequency in a time-division duplex mode.

19. A wireless terrestrial component according to claim 17 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first one portion thereof is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency and wherein at least a second one portion thereof is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency.

20. A wireless terrestrial component according to claim 17 wherein the uplink satellite radiotelephone frequency comprises an uplink satellite radiotelephone frequency band and wherein the electronics system is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over an uplink satellite radiotelephone frequency band in a time-division duplex mode.

21. A wireless terrestrial component according to claim 17 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame including a plurality of slots, wherein a first portion of the transmit/receive time interval and/or frame and/or a first number of the slots is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency and wherein a second portion of the transmit/receive time interval and/or frame and/or a second number of the slots is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency.

22. A wireless terrestrial component according to claim 17 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first one portion thereof is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency using OFDM and/or OFDMA and M-ary QAM modulation and/or protocol and wherein at least a second one portion thereof is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency using OFDM and/or OFDMA and L-ary QAM modulation and/or protocol and wherein L≦

M, and M, L≧

1.

23. A wireless terrestrial component according to claim 17 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first one portion thereof is used to transmit wireless communications to radiotelephones over an uplink satellite radiotelephone frequency using a first modulation and/or protocol and wherein at least a second one portion thereof is used to receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency using a second modulation and/or protocol, wherein the first modulation and/or protocol is more spectrally efficient than the second modulation and/or protocol.

24. A wireless terrestrial component according to claim 17:

wherein the space-based component is configured to receive wireless communications from a first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band and to transmit wireless communications to the first radiotelephone in the satellite footprint over a downlink satellite radiotelephone frequency band;

wherein the wireless terrestrial component is configured to transmit wireless communications to, and/or receive wireless communications from, a second radiotelephone over an uplink satellite radiotelephone frequency band, the space-based component also receiving the wireless communications from the second radiotelephone and/or the wireless terrestrial component over an uplink satellite radiotelephone frequency band as interference along with the wireless communications that are received from the first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band.

25. A wireless terrestrial component according to claim 24:

wherein the wireless terrestrial component is further configured to transmit to a satellite gateway, a measure of the wireless communications that are transmitted to, and the wireless communications that are received from, the second radiotelephone.

26. A wireless terrestrial component according to claim 24:

wherein the wireless terrestrial component further comprises an interference reducer that is responsive to the space-based component, and that is configured to reduce the interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or the wireless terrestrial component over an uplink satellite radiotelephone frequency band, using the wireless communications that are transmitted by the wireless terrestrial component to, and/or received by the wireless terrestrial component from, the second radiotelephone over an uplink satellite radiotelephone frequency band.

27. A wireless terrestrial component according to claim 26 wherein the wireless terrestrial component is closer to the second radiotelephone than to the space-based component such that the wireless communications from the second radiotelephone are received by the wireless terrestrial component and the wireless communications from the wireless terrestrial component to the second radiotelephone are generated by the wireless terrestrial component prior to reception by the space-based component and wherein the interference reducer is configured to generate at least one delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial component and/or the wireless communications from the wireless terrestrial component to the second radiotelephone, and to subtract a measure of the delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial component and/or the wireless communications from the wireless terrestrial component to the second radiotelephone, from the wireless communications that are received from the space-based component.

28. A wireless terrestrial component according to claim 26 wherein the interference reducer comprises an adaptive interference reducer.

29. A radiotelephone comprising:

an electronics system that is configured to transmit wireless communications to, and receive wireless communications from, a wireless terrestrial component over an uplink satellite radiotelephone frequency in a time-division duplex mode.

30. A radiotelephone according to claim 29 wherein the electronics system also is configured to transmit wireless communications to, and receive wireless communications from, the wireless terrestrial component over a downlink satellite radiotelephone frequency in a time-division duplex mode.

31. A radiotelephone according to claim 29 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first portion is used to transmit wireless communications to the wireless terrestrial component over an uplink satellite radiotelephone frequency and wherein at least a second portion is used to receive wireless communications from the wireless terrestrial component over an uplink satellite radiotelephone frequency.

32. A radiotelephone according to claim 29 wherein the uplink satellite radiotelephone frequency comprises an uplink satellite radiotelephone frequency band and wherein the electronics system also is configured to transmit wireless communications to, and receive wireless communications from, the wireless terrestrial component over an uplink satellite radiotelephone frequency band in a time-division duplex mode.

33. A radiotelephone according to claim 29 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame including a plurality of slots, wherein a first portion of the transmit/receive time interval and/or frame and/or a first number of the slots is used to receive wireless communications at the radiotelephone over an uplink satellite radiotelephone frequency and wherein a second portion of the transmit/receive time interval and/or frame and/or a second number of the slots is used to transmit wireless communications by the radiotelephone over an uplink satellite radiotelephone frequency.

34. A radiotelephone according to claim 29 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first portion thereof is used to receive wireless communications at the radiotelephone over an uplink satellite radiotelephone frequency using OFDM and/or OFDMA and M-ary QAM modulation and/or protocol and wherein at least a second portion thereof is used to transmit wireless communications by the radiotelephone over an uplink satellite radiotelephone frequency using OFDM and/or OFDMA and L-ary QAM modulation and/or protocol, wherein L<

M, and L and M are greater than or equal to one.

35. A radiotelephone according to claim 29 wherein the time-division duplex mode includes a transmit/receive time interval and/or frame, wherein at least a first one portion thereof is used to receive wireless communications at the radiotelephone over an uplink satellite radiotelephone frequency using a first modulation and/or protocol and wherein at least a second one portion thereof is used to transmit wireless communications by the radiotelephone over an uplink satellite radiotelephone frequency using a second modulation and/or protocol, wherein the first modulation and/or protocol is more spectrally efficient than the second modulation and/or protocol.

36. A radiotelephone according to claim 29 wherein the electronics system is further configured to transmit wireless communications to a space-based component over an uplink satellite radiotelephone frequency and to receive wireless communications from the space-based component over a downlink satellite radiotelephone frequency.

37. A radiotelephone according to claim 30 wherein the electronics system is further configured to transmit wireless communications to a space-based component over an uplink satellite radiotelephone frequency and to receive wireless communications from the space-based component over a downlink satellite radiotelephone frequency.

38. A gateway for a satellite radiotelephone system that includes a space-based component that is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency and to transmit wireless communications to radiotelephones over a downlink satellite radiotelephone frequency, and a wireless terrestrial network that is configured to transmit wireless communications to, and receive wireless communications from radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode, the gateway comprising:

an electronics system that is configured to receive from the space-based component, the wireless communications that are received at the space-based component from radiotelephones over an uplink satellite radiotelephone frequency and is further configured to receive from the wireless terrestrial network, the wireless communications that are transmitted to and received from radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode.

39. A gateway according to claim 38:

wherein the space-based component is configured to receive wireless communications from a first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band and to transmit wireless communications to the first radiotelephone in the satellite footprint over a downlink satellite radiotelephone frequency band;

wherein the wireless terrestrial network is configured to transmit wireless communications to, and receive wireless communications from, a second radiotelephone over an uplink satellite radiotelephone frequency band, the space-based component also receiving the wireless communications from the second radiotelephone and/or the wireless terrestrial network over an uplink satellite radiotelephone frequency band as interference along with the wireless communications that are received from the first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band; and

wherein the gateway further comprises an interference reducer that is responsive to the space-based component and to the wireless terrestrial network, and that is configured to reduce the interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or the wireless terrestrial network over an uplink satellite radiotelephone frequency band, using the wireless communications that are transmitted by the wireless terrestrial network to, and/or received by the wireless terrestrial network from, the second radiotelephone over an uplink satellite radiotelephone frequency band.

40. A gateway according to claim 39 wherein the wireless terrestrial network is closer to the second radiotelephone than to the space-based component such that the wireless communications from the second radiotelephone are received by the wireless terrestrial network and the wireless communications from the wireless terrestrial network to the second radiotelephone are generated by the wireless terrestrial network prior to reception by the space-based component and wherein the interference reducer is configured to generate at least one delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications from the wireless terrestrial network to the second radiotelephone, and to subtract a measure of the delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications from the wireless terrestrial network to the second radiotelephone, from the wireless communications that are received from the space-based component.

41. A gateway according to claim 39 wherein the interference reducer comprises an adaptive interference reducer.

42. A satellite radiotelephone communication method comprising:

receiving wireless communications at a space-based component from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency;

transmitting wireless communications from the space-based component to radiotelephones over a downlink satellite radiotelephone frequency;

transmitting wireless communications from a wireless terrestrial network to radiotelephones and transmitting wireless communications from radiotelephones to the wireless terrestrial network over an uplink satellite radiotelephone frequency in a time-division duplex mode.

43. A method according to claim 42 further comprising:

transmitting wireless communications from the wireless terrestrial network to radiotelephones and transmitting wireless communications from radiotelephones to the wireless terrestrial network over a downlink satellite radiotelephone frequency in a time-division duplex mode.

44. A satellite radiotelephone method according to claim 42:

wherein receiving wireless communications at a space-based component comprises receiving wireless communications at the space-based component from a first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band;

wherein transmitting wireless communications from the space-based component comprises transmitting wireless communications from the space-based component to the first radiotelephone in the satellite footprint over a downlink satellite radiotelephone frequency band;

wherein transmitting wireless communications from a wireless terrestrial network to radiotelephones and transmitting wireless communications from radiotelephones to the wireless terrestrial network comprises transmitting wireless communications from the wireless terrestrial network to a second radiotelephone and transmitting wireless communications from the second radiotelephone to the wireless terrestrial network over an uplink satellite radiotelephone frequency band, the space-based component also receiving the wireless communications that are transmitted from the second radiotelephone and/or the wireless terrestrial network over an uplink satellite radiotelephone frequency band as interference along with the wireless communications that are received from the first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band; and

wherein the method further comprises reducing the interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or from the wireless terrestrial network over an uplink satellite radiotelephone frequency band, using the wireless communications that are transmitted from the wireless terrestrial network to, and/or received by the wireless terrestrial network from, the second radiotelephone over an uplink satellite radiotelephone frequency band.

45. A method according to claim 44 wherein the wireless terrestrial network is closer to the second radiotelephone than to the space-based component such that the wireless communications from the second radiotelephone are received by the wireless terrestrial network and the wireless communications from the wireless terrestrial network to the second radiotelephone are transmitted by the wireless terrestrial network prior to reception by the space-based component, and wherein reducing interference comprises:

generating at least one delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications that are transmitted from the wireless terrestrial network to the second radiotelephone; and

subtracting a measure of the delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications that are transmitted from the wireless terrestrial network to the second radiotelephone, from the wireless communications that are received from the space-based component.

46. A method of operating a wireless terrestrial component in a satellite radiotelephone system that includes a space-based component that is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency and to transmit wireless communications to radiotelephones over a downlink satellite radiotelephone frequency, the wireless terrestrial component operating method comprising:

transmitting wireless communications to, and receiving wireless communications from, radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode.

47. A method according to claim 46 further comprising:

transmitting wireless communications to, and receiving wireless communications from, radiotelephones over downlink satellite radiotelephone frequency in a time-division duplex mode.

48. A method according to claim 46:

wherein the space-based component is configured to receive wireless communications from a first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band and to transmit wireless communications to the first radiotelephone in the satellite footprint over a downlink satellite radiotelephone frequency band; and

wherein the wireless terrestrial component operating method further comprises transmitting wireless communications to, and/or receiving wireless communications from, a second radiotelephone over an uplink satellite radiotelephone frequency band, the space-based component also receiving the wireless communications from the second radiotelephone and/or from the wireless terrestrial component over an uplink satellite radiotelephone frequency band as interference along with the wireless communications that are received from the first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band.

49. A method according to claim 48 further comprising:

transmitting from the wireless terrestrial component to a satellite gateway, a measure of the wireless communications that are transmitted to, and the wireless communications that are received from, the second radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band.

50. A method according to claim 48 wherein the wireless terrestrial component operating method further comprises:

reducing the interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or from the wireless terrestrial component over an uplink satellite radiotelephone frequency band, using the wireless communications that are transmitted by the wireless terrestrial component to, and/or received by the wireless terrestrial component from, the second radiotelephone over an uplink satellite radiotelephone frequency band.

51. A method according to claim 50 wherein the wireless terrestrial component is closer to the second radiotelephone than to the space-based component such that the wireless communications from the second radiotelephone are received by the wireless terrestrial component and the wireless communications from the wireless terrestrial component to the second radiotelephone are generated by the wireless terrestrial component prior to reception by the space-based component, and wherein reducing interference comprises:

generating at least one delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial component and/or the wireless communications that are transmitted from the wireless terrestrial component to the second radiotelephone; and

subtracting a measure of the delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial component and/or the wireless communications that are transmitted from the wireless terrestrial component to the second radiotelephone, from the wireless communications that are received from the space-based component.

52. A radiotelephone operating method comprising:

transmitting wireless communications to, and receiving wireless communications from, a wireless terrestrial component over an uplink satellite radiotelephone frequency in a time-division duplex mode.

53. A method according to claim 52 further comprising:

transmitting wireless communications to a space-based component over an uplink satellite radiotelephone frequency; and

receiving wireless communications from the space-based component over a downlink satellite radiotelephone frequency.

54. A method according to claim 52 further comprising:

transmitting wireless communications to, and receiving wireless communications from, a wireless terrestrial component over a downlink satellite radiotelephone frequency in a time-division duplex mode.

55. A method of operating a gateway of a satellite radiotelephone system that includes a space-based component that is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency and to transmit wireless communications to radiotelephones over a downlink satellite radiotelephone frequency, and a wireless terrestrial network that is configured to transmit wireless communications to, and receive wireless communications from, radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode, the gateway operating method comprising:

receiving from the space-based component, the wireless communications that are received at the space-based component from radiotelephones over an uplink satellite radiotelephone frequency; and

receiving from the wireless terrestrial network, the wireless communications that are transmitted to and received from the radiotelephones over an uplink satellite radiotelephone frequency in a time-division duplex mode.

56. A method according to claim 55:

wherein the space-based component is configured to receive wireless communications from a first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band and to transmit wireless communications to the first radiotelephone in the satellite footprint over a downlink satellite radiotelephone frequency band;

wherein the wireless terrestrial network is configured to transmit wireless communications to, and receive wireless communications from, a second radiotelephone over an uplink satellite radiotelephone frequency band, the space-based component also receiving the wireless communications from the second radiotelephone and/or the wireless terrestrial network over an uplink satellite radiotelephone frequency band as interference along with the wireless communications that are received from the first radiotelephone in the satellite footprint over an uplink satellite radiotelephone frequency band; and

wherein the gateway operating method further comprises reducing the interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or from the wireless terrestrial network over an uplink satellite radiotelephone frequency band, using the wireless communications that are transmitted by the wireless terrestrial network to, and/or received by the wireless terrestrial network from, the second radiotelephone over an uplink satellite radiotelephone frequency band.

57. A method according to claim 56 wherein the wireless terrestrial network is closer to the second radiotelephone than to the space-based component such that the wireless communications from the second radiotelephone are received by the wireless terrestrial network and the wireless communications from the wireless terrestrial network are transmitted to the second radiotelephone prior to reception by the space-based component, and wherein reducing interference comprises:

generating at least one delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and/or the wireless communications that are transmitted from the wireless terrestrial network to the second radiotelephone; and

subtracting a measure of the delayed replica of the wireless communications from the second radiotelephone that are received by the wireless terrestrial network and the wireless communications that are transmitted from the wireless terrestrial network to the second radiotelephone, from the wireless communications that are received from the space-based component.