Upstream broad beam diversity with interference cancellation

• US 7,929,909 B2
• Filed: 08/22/2007
• Issued: 04/19/2011
• Est. Priority Date: 08/22/2006
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Pateros, Charles N., Dankberg, Mark D.
• Primary Examiner(s): Gesesse; Tilahun
• Application Number:
  US11/843,429
• Publication Number:
  US 20080214107A1
• Time in Patent Office: 1,336 Days
• Field of Search: 455/12.1, 455/13.1, 455/427, 455/428, 455/429, 455/431, 455/13.4
• US Class Current: 455/13.4
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays
• CPC Class Codes: H04B 7/18517 Transmission equipment in earth stations
• CPC Class Codes: H04B 7/2041 Spot beam multiple access
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 5/0016 Time-frequency-code
• CPC Class Codes: H04L 5/0026 Division using four or more dimensions
• CPC Class Codes: H04L 5/12 the signals being represented by different phase modulations of a single carrier

Abstract

A satellite communication system is provided according to one embodiment of the invention. The satellite communication system includes a gateway with first and second antennas. The first antenna receives a signal from a first satellite that includes at least a first signal from a first user. The second antenna receives a second signal from a second satellite, that includes at least a second primary signal from a second user and a version of the first signal. The gateway may include circuitry to isolate the first signal from the second signal. The gateway may also include a combiner configured to combine the first signal from the first satellite and the first signal isolated from the second signal. Various other embodiments are disclosed that isolate a secondary signal received from a satellite and combine the secondary signal with the same signal received from other antennas at the gateway.

Claims

1. A satellite communication gateway comprising:

a first antenna configured to receive a signal from a first satellite, wherein the signal received from the first satellite includes at least a first signal from a first user;

a second antenna configured to receive a second signal from a second satellite, wherein the second signal includes at least a second primary signal from a second user and a second secondary signal;

a demodulator-remodulator configured to isolate the second secondary signal from the second signal; and

a combiner configured to synchronize the first signal and the second signal and combine the first signal and the second secondary signal to generate a received signal having a higher apparent signal strength than that of the first signal alone,

wherein the combiner is a maximal ratio combiner, and

wherein the second secondary signal includes a version of the first signal.

2. The satellite communication gateway of claim 1, further comprising:

a third antenna configured to receive a third signal from a third satellite, wherein the signal received from the third satellite includes at least a third primary signal from a third user and a third secondary signal;

a second demodulator-remodulator configured to isolate the third secondary signal from the third signal;

wherein the combiner is configured to combine the first signal, the second secondary signal and the third secondary signal to generate the received signal,

wherein the third secondary signal includes a version of the first signal.

3. The satellite communication gateway of claim 2, wherein the first user does not lease access to the third satellite.

4. The satellite communication gateway of claim 1, wherein the first user leases access to the first satellite.

5. The satellite communication gateway of claim 1, wherein the first user does not lease access to the second satellite.

6. A satellite communication method comprising:

receiving a signal from a first satellite, wherein the signal from the first satellite includes at least a first signal from a first user;

receiving a signal from a second satellite, wherein the signal from the second satellite includes at least a second primary signal from a second user and a second secondary signal;

canceling the second primary signal from the second signal to generate a modified second signal; and

synchronizing the first signal and second signal and combining the modified second signal and the first signal to generate a received signal having a higher apparent signal strength than that of the first signal alone,

wherein the combining includes maximal ratio combining, and

wherein the second secondary signal includes a version of the first signal.

7. The method according to claim 6, further comprising delaying either the first or the second signal prior to the combining.

8. The method according to claim 6, wherein the canceling includes demodulating the second signal using noise canceling techniques.

9. The method according to claim 6, wherein the first user leases access to the first satellite.

10. The method according to claim 6, wherein the first user does not lease access to the second satellite.

11. The method according to claim 6, further comprising:

receiving a third signal from a third satellite, wherein the third signal from the third satellite includes at least a third primary signal from a third user and a third secondary signal;

canceling the third primary signal from the third signal to generate a modified third signal; and

combining the modified third signal, the modified second signal, and the first signal to generate the received signal,

wherein the third secondary signal includes a version of the first signal.

12. The method according to claim 11, wherein the first user does not lease access to the third satellite.

13. A satellite communication method comprising:

receiving a first signal from a first satellite, wherein the first signal includes at least a first primary signal from a first user and a second signal from a second user;

receiving a third signal from a second satellite, wherein the third signal includes at least a third primary signal from a third user and a version of the second signal;

isolating the second signal from the first signal;

isolating the version of the second signal from the third signal; and

synchronizing the first signal and second signal and the second signal isolated from the first signal and the second signal isolated from the third signal to generate a received signal having a higher apparent signal strength than that of the second signal alone, wherein the combining includes maximal ratio combining.

14. The satellite communication method according to claim 13, wherein the second user does not lease access to the first satellite and the second user does not lease access to the third satellite.