MIMO SATELLITE SYSTEM

• US 20090034448A1
• Filed: 01/09/2008
• Published: 02/05/2009
• Est. Priority Date: 01/09/2007
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Miller, Mark J., Das, Aniruddha, Eidenschink, Thomas
• Granted Patent: US 8,130,693 B2
• Time in Patent Office: Days
• US Class Current: 370/316
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/18508 with satellite system used as relay, i.e. aeronautical mobile satellite service
• CPC Class Codes: H04B 7/18534 for enhancing link reliablility, e.g. satellites diversity
• CPC Class Codes: H04B 7/1858 Arrangements for data transmission on the physical system, i.e. for data bit transmission between network components

Abstract

A satellite communication system is disclosed that utilizes multiple antenna for subscriber terminals to process streams. A first node relays a first stream between the ground station and the subscriber terminals. A second node relays the second lower information rate signal to the subscriber terminals. Spatial relationships are used to differentiate the first stream from the second stream. At least one of the first and second nodes includes a satellite, and the first and second nodes are separated by 50 miles or more. Optionally, frequency ranges for the first and second streams overlap in time. In some cases, the second stream can contain additional information where the second node is terrestrial.

Claims

1. A satellite communication system for bi-directional communication, the satellite communication system comprising:

a plurality of subscriber terminals, wherein;

each of the plurality of subscriber terminals uses a plurality of antenna,

the plurality of subscriber terminals utilize at least some spatial multiplexing, and

each of the plurality of subscriber terminals is configured to process a higher information rate signal constructed from at least a first lower information rate signal and a second lower information rate signal;

a first node to relay the first lower information rate signal between the ground station and the plurality of subscriber terminals; and

a second node to relay the second lower information rate signal to the plurality of subscriber terminals, wherein;

at least one of the first and second nodes comprises a satellite,

the first and second nodes are separated by 50 miles or more,

the first lower information rate signal uses a first frequency range for relaying information to the plurality of subscriber terminals,

the second lower information rate signal uses a second frequency range for relaying information to the plurality of subscriber terminals, and

use of the first and second frequency ranges at least partially overlap in frequency coincident in time.

2. The satellite communication system for bi-directional communication as recited in claim 1, wherein:

the first lower information rate signal relays first information for the plurality of subscriber terminals,

the second lower information rate signal relaying second information for the plurality of subscriber terminals, and

the second information comprises the first information and additional information.

3. The satellite communication system for bi-directional communication as recited in claim 1, wherein the satellite moves over time while operational.

4. The satellite communication system for bi-directional communication as recited in claim 1, wherein:

the first node comprises the satellite,

the second node comprises a second satellite, and

the satellite and the second satellite are in different orbital slots.

5. The satellite communication system for bi-directional communication as recited in claim 1, wherein:

the first node comprises the satellite,

the second node comprises a second satellite, and

the satellite and the second satellite are separated by at least 2 degrees.

6. The satellite communication system for bi-directional communication as recited in claim 1, wherein at least some of the plurality of subscriber terminals are mobile subscriber terminals.

7. The satellite communication system for bi-directional communication as recited in claim 1, wherein the plurality of subscriber terminals utilize spatial diversity.

8. The satellite communication system for bi-directional communication as recited in claim 1, wherein:

the first lower information rate signal uses a first coding and modulation,

the second lower information rate signal uses a second coding and modulation, and

the first coding and modulation is different from the second coding and modulation.

9. The satellite communication system for bi-directional communication as recited in claim 1, wherein the first node is a satellite and the second node is a terrestrial base station.

10. The satellite communication system for bi-directional communication as recited in claim 1, wherein the first and second lower information rate signals have at least partially overlapping information.

11. The satellite communication system for bi-directional communication as recited in claim 1, wherein the first node includes a plurality of transmit antennas that use directional beam forming.

12. The satellite communication system for bi-directional communication as recited in claim 1, wherein the first node uses polarization diversity when communicating with the plurality of subscriber terminals.

13. The satellite communication system for bi-directional communication as recited in claim 1, wherein:

the first node is nulled when processing a first time by one of the plurality of subscriber terminals, and

the second node is nulled when processing a second time by the one of the plurality of subscriber terminals.

14. A satellite communication system for wireless communication, comprising:

a plurality of subscriber terminals, wherein;

each of the plurality of subscriber terminals uses a plurality of antenna, and

each of the plurality of subscriber terminals is configured to process signals from the plurality of antenna using spatial relationships to differentiate streams;

a first node to relay a first stream between the ground station and the plurality of subscriber terminals; and

a second node to relay a second stream to the plurality of subscriber terminals, wherein;

at least one of the first and second nodes comprises a satellite,

the first and second nodes are separated by 100 miles or more,

the first stream uses a first frequency range for relaying information to the plurality of subscriber terminals,

the second stream uses a second frequency range for relaying information to the plurality of subscriber terminals, and

use of the first and second frequency ranges at least partially overlap in frequency coincident in time.

15. The satellite communication system for wireless communication as recited in claim 14, wherein the plurality of subscriber terminals use spatial multiplexing to decode unique information on the streams.

16. The satellite communication system for wireless communication as recited in claim 14, wherein:

the first node comprises the satellite,

the second node comprises a second satellite, and

the satellite and the second satellite are in different orbital slots

17. A method for communicating with orbital satellite links, the method comprising steps of:

receiving with a first antenna at a subscriber terminal the first stream and the second stream, wherein;

the first stream is generated by a first node,

the second stream is generated by a second node, and

the first and second nodes are separated by at least 200 miles,

at least one of the first and second nodes comprises a satellite;

receiving with a second antenna at a subscriber terminal the first stream and the second stream, wherein;

the first stream uses a first frequency range for relaying information,

the second stream uses a second frequency range for relaying 14 information, and

the first and second frequency ranges at least partially overlap and are used coincident in time;

processing signals from the first and second antennas to determine the first and second streams, wherein the processing step comprises a sub-step of analyzing a relationship between the first node, the second node and the first and second antenna to spatially differentiate the first stream from the second stream.

18. The method for communicating with orbital satellite links as recited in claim 17, wherein:

the first stream comprises first information,

the second stream comprises second information, and

the second information comprises the first information and additional information.

19. The method for communicating with orbital satellite links as recited in claim 17, wherein:

the first lower information rate signal uses a first coding and modulation,

the second lower information rate signal uses a second coding and modulation, and

the first coding and modulation is different from the second coding and modulation.

20. The method for communicating with orbital satellite links as recited in claim 17, wherein the first and second stream encapsulate overlapping information.

21. The method for communicating with orbital satellite links as recited in claim 17, wherein the first and second stream encapsulate different information.

22. The method for communicating with orbital satellite links as recited in claim 17, wherein the first node is a satellite and the second node is a terrestrial base station.

23. The method for communicating with orbital satellite links as recited in claim 17, wherein the first and second nodes are separated by miles.

24. The method for communicating with orbital satellite links as recited in claim 17, wherein the processing step comprises a sub-step of performing MMSE estimation to choose one of the first or second stream.

25. A satellite communication system for wireless communication, the satellite communication system comprising:

a plurality of subscriber terminals, wherein each of the plurality of subscriber terminals uses a plurality of antenna to receive a first stream and a second stream;

a first node to relay the first stream between the ground station and the plurality of subscriber terminals;

a second node to relay the second stream to the plurality of subscriber terminals, wherein;

at least one of the first and second nodes comprises a satellite,

the first stream uses a first frequency range for relaying information to the plurality of subscriber terminals,

the second stream uses a second frequency range for relaying information to the plurality of subscriber terminals,

use of the first and second frequency ranges at least partially overlap in time,

the first stream relays first information for the plurality of subscriber terminals,

the second stream relays second information for the plurality of subscriber terminals, and

the second information comprises;

at least some of the first information and

additional information.

26. The satellite communication system for wireless communication as recited in claim 25, wherein the second node is a terrestrial base station.

27. The satellite communication system for wireless communication as recited in claim 25, wherein the second stream carries more information than the first stream.

28. The satellite communication system for wireless communication as recited in claim 25, wherein the second information is localized for various geographic regions associated with the plurality of subscriber terminals.

29. The satellite communication system for wireless communication as recited in claim 25, wherein:

a location is known for one of the plurality of subscriber terminals, and

the second information is customized according to the location.

30. The satellite communication system for wireless communication as recited in claim 25, wherein:

the second information is determined to be low latency traffic, and

the second node is a terrestrial node.

31. The satellite communication system for wireless communication as recited in claim 25, wherein the additional information is sent with higher-order signaling.

32. The satellite communication system for wireless communication as recited in claim 25, wherein the second node receives the first stream from a satellite and the second stream from a terrestrial network.

33. The satellite communication system for wireless communication as recited in claim 25, wherein each of the plurality of subscriber terminals is configured to process signals from the plurality of antenna using determined spatial relationships to differentiate the first stream from the second stream.

34. A method for communicating with orbital satellite links, the method comprising steps of:

receiving with a first antenna at a subscriber terminal a first stream and a second stream, wherein;

the first stream is generated by a first node,

the second stream is generated by a second node,

the second stream operates at a higher symbol rate than the first stream,

the first node comprises a terrestrial base station, and

the second nodes comprises a satellite;

receiving with a second antenna at a subscriber terminal the first stream and the second stream; and

processing signals from the first and second antennas using determined spatial relationships to differentiate the first stream from the second stream.

35. The method for communicating with orbital satellite links as recited in claim 34, wherein the first and second streams utilize spatial multiplexing.

36. The method for communicating with orbital satellite links as recited in claim 34, wherein:

the first stream uses a first frequency range for relaying information,

the second stream uses a second frequency range for relaying information, and

the first and second frequency ranges at least partially overlap.

37. The method for communicating with orbital satellite links as recited in claim 34, wherein the first stream includes additional information that is localized for various geographic regions associated with a subscriber terminal comprising the first and second antenna.

38. The method for communicating with orbital satellite links as recited in claim 34, further comprising steps of:

determining a location is known for a subscriber terminal comprising the first and second antennas; and

customizing the first stream according to the location.

39. The method for communicating with orbital satellite links as recited in claim 34, wherein the processing step comprises a sub-step of nulling the first node when processing signaling from the second node.

40. A satellite communication system for wireless communication, the satellite communication system comprising:

a plurality of subscriber terminals, wherein;

each of the plurality of subscriber terminals uses a plurality of antenna to receive a first stream and a second stream, and

each of the plurality of subscriber terminals is configured to process signals from the plurality of antenna using determined spatial relationships to differentiate streams;

a first node to relay the first stream between the ground station and the plurality of subscriber terminals;

a second node to relay the second stream to the plurality of subscriber terminals, wherein;

at least one of the first and second nodes comprises a satellite,

the first stream relays first information for the plurality of subscriber terminals,

the second stream relays second information for the plurality of subscriber terminals, and

the second information comprises;

at least some of the first information and

additional information.

41. The satellite communication system for wireless communication as recited in claim 40, wherein:

the first stream uses a first frequency range for relaying information to the plurality of subscriber terminals,

the second stream uses a second frequency range for relaying information to the plurality of subscriber terminals, and

use of the first and second frequency ranges at least partially overlap in time.

42. The satellite communication system for wireless communication as recited in claim 40, wherein the second node is a terrestrial base station.

43. The satellite communication system for wireless communication as recited in claim 40, wherein the second stream carries more information than the first stream.

44. The satellite communication system for wireless communication as recited in claim 40, wherein the second information is localized for various geographic regions associated with the plurality of subscriber terminals.

45. The satellite communication system for wireless communication as recited in claim 40, wherein:

a location is known for one of the plurality of subscriber terminals, and

the second information is customized according to the location.

46. The satellite communication system for wireless communication as recited in claim 40, wherein:

the second information is determined to be low latency traffic, and

the second node is a terrestrial node.

47. The satellite communication system for wireless communication as recited in claim 40, wherein the additional information is sent with higher-order signaling.