Bent pipe beam switching for virtual utility gateways

• US 8,509,144 B2
• Filed: 12/07/2012
• Issued: 08/13/2013
• Est. Priority Date: 12/08/2011
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Miller, Mark J., Pateros, Charles N.
• Primary Examiner(s): Duong, Frank
• Application Number:
  US13/708,493
• Publication Number:
  US 20130148570A1
• Time in Patent Office: 249 Days
• Field of Search: 370/310, 370315-326, 370339-345, 455/3.02, 455427-431
• US Class Current: 370/326
• CPC Class Codes: H04B 7/18515 Transmission equipment in satellites or space-based relays
• CPC Class Codes: H04B 7/2041 Spot beam multiple access
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

A method for communicating includes utilizing a satellite comprising receivers, transmitters, transmit switches, and a gateway switch structure. Prior to a time T, each of at least P receivers are used to receive one of at least P signals from P gateway terminals. During one frame, the gateway switch structure is used to switch the at least P signals to the plurality of transmit switches. Each of the at least P signals are switched into fixed location beams. After time T and before a time T2, each of at least Q receivers are used to receive a different one of at least Q signals from Q gateway terminals. During one frame, the gateway switch structure is used to switch the at least Q signals to the plurality of transmit switches. Each of the at least Q signals are switched into fixed location beams. Q and P are non-zero positive integers and Q<P.

Claims

1. A method for communicating using a satellite having a forward link capability comprising:

providing the satellite, the satellite comprising a plurality of receivers having inputs and outputs, a plurality of transmitters having inputs and outputs, the inputs of the plurality of transmitters coupled to the outputs of the plurality of receivers, a plurality of transmit switches coupled to the outputs of the plurality of transmitters, and a gateway switch structure coupled to at least one of;

(a) the inputs of the plurality of receivers, (b) the outputs of the plurality receivers and the inputs of the plurality of transmitters, or (c) the outputs of the plurality of transmitters;

using each transmit switch in the plurality of transmit switches to sequentially switch a forward link signal into multiple fixed location beams according to a beam group transmit switching pattern;

prior to a time T1, using each of at least P receivers in the plurality of receivers to receive a different one of at least P forward link signals from P gateway terminals, and in the duration of one frame, using the gateway switch structure to sequentially switch the at least P forward link signals from the P gateway terminals, in order to provide the at least P forward link signals to the plurality of transmit switches, according to a first gateway switching pattern, and sequentially switching each of the at least P forward link signals into fixed location beams according to a first beam group transmit switching pattern;

after time T1 and before a time T2, using each of at least Q receivers in the plurality of receivers to receive a different one of at least Q forward link signals from Q gateway terminals, and in the duration of one frame, using the gateway switch structure to sequentially switch the at least Q forward link signals from the Q gateway terminals, in order to provide the at least Q forward link signals to the plurality of transmit switches, according to a second gateway switching pattern, and sequentially switching each of the at least Q forward link signals into fixed location beams according to a second beam group transmit switching pattern;

wherein P and Q are both non-zero, positive integers, and Q<

P; and

wherein the first and second gateway switching patterns are different.

2. The method of claim 1, wherein the gateway switch structure comprises a switch matrix positioned between the plurality of receivers and the plurality of transmitters.

3. The method of claim 1, wherein the gateway switch structure comprises at least one receive-side outer switch positioned before the plurality of receivers.

4. The method of claim 1, wherein each of the plurality of receivers comprises a low noise amplifier (LNA).

5. The method of claim 1, wherein each of plurality of transmitters comprises a high power amplifier (HPA).

6. The method of claim 1, wherein the first and second beam group transmit switching patterns are different.

7. The method of claim 1, wherein the gateway switch structure changes from sequentially switching the at least P forward link signals to sequentially switching the at least Q forward link signals, as a result of rain fade making at least one gateway terminal unavailable.

8. The method of claim 1, wherein after time T2, the at least P receivers in the plurality of receivers are each configured to receive a different one of the at least P forward link signals from the P gateway terminals, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the at least P forward link signals from the P gateway terminals, in order to provide the at least P forward link signals to the plurality of transmit switches, according to the first gateway switching pattern, and each of the at least P forward link signals is sequentially switched into fixed location beams according to the first beam group transmit switching pattern.

9. The method of claim 8, wherein the gateway switch structure reverts from sequentially switching the at least Q forward link signals to sequentially switching the at least P forward link signals, as result of disappearance of rain fade making at least one gateway terminal available again.

10. The method of claim 1, wherein the satellite has return link capability in addition to forward link capability and further comprises a plurality of receive switches coupled to the inputs of the plurality of receivers, the method further comprising:

using each receive switch in the plurality of receive switches to sequentially switch return link signals from fixed location beams into a receiver according to a beam group receive switching pattern;

prior to time T1, sequentially switching the return link signals from multiple fixed location beams into the plurality of receivers according to a first beam group receive switching pattern, and in the duration of one frame, using the gateway switch structure to sequentially switch the return link signals to at least P transmitters in the plurality of transmitters according to the first gateway switching pattern, and using each of the at least P transmitters to transmit a different one of the return link signals to one of the P gateway terminals; and

after time T1 and before time T2, sequentially switching the return link signals from multiple fixed location beams into the plurality of receivers according to a second beam group receive switching pattern, and in the duration of one frame, using the gateway switch structure to sequentially switch the return link signals to at least Q transmitters in the plurality of transmitters according to the second gateway switching pattern, and using each of the at least Q transmitters to transmit a different one of the return link signals to one of the Q gateway terminals.

11. A satellite communication system having a forward link capability comprising:

a plurality of gateway terminals;

a plurality of user terminals;

a satellite for providing hub-spoke communications between the gateway terminals and the user terminals, the satellite comprising a plurality of receivers having inputs and outputs, a plurality of transmitters having inputs and outputs, the inputs of the plurality of transmitters coupled to the outputs of the plurality of receivers, a plurality of transmit switches coupled to the outputs of the plurality of transmitters, and a gateway switch structure coupled to at least one of;

(a) the inputs of the plurality of receivers, (b) the outputs of the plurality receivers and the inputs of the plurality of transmitters, or (c) the outputs of the plurality of transmitters;

wherein each transmit switch in the plurality of transmit switches is configured to sequentially switch a forward link signal into multiple fixed location beams according to a beam group transmit switching pattern;

wherein prior to a time T1, at least P receivers in the plurality of receivers are each configured to receive a different one of at least P forward link signals from P gateway terminals, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the at least P forward link signals from the P gateway terminals, in order to provide the at least P forward link signals to the plurality of transmit switches, according to a first gateway switching pattern, and each of the at least P forward link signals is sequentially switched into fixed location beams according to a first beam group transmit switching pattern;

wherein after time T1 and before a time T2, at least Q receivers in the plurality of receivers are each configured to receive a different one of at least Q forward link signals from Q gateway terminals, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the at least Q forward link signals from the Q gateway terminals, in order to provide the at least Q forward link signals to the plurality of transmit switches, according to a second gateway switching pattern, and each of the at least Q forward link signals is sequentially switched into fixed location beams according to a second beam group transmit switching pattern;

wherein P and Q are both non-zero, positive integers, and Q<

P; and

wherein the first and second gateway switching patterns are different.

12. The satellite communication system of claim 11, wherein the gateway switch structure comprises a switch matrix positioned between the plurality of receivers and the plurality of transmitters.

13. The satellite communication system of claim 11, wherein the gateway switch structure comprises at least one receive-side outer switch positioned before the plurality of receivers.

14. The satellite communication system of claim 11, wherein each of the plurality of receivers comprises a low noise amplifier (LNA).

15. The satellite communication system of claim 11, wherein each of plurality of transmitters comprises a high power amplifier (HPA).

16. The satellite communication system of claim 11, wherein the first and second beam group transmit switching patterns are different.

17. The satellite communication system of claim 11, wherein the gateway switch structure changes from sequentially switching the at least P forward link signals to sequentially switching the at least Q forward link signals, as result of rain fade making at least one gateway terminal unavailable.

18. The satellite communication system of claim 11, wherein after time T2, the at least P receivers in the plurality of receivers are each configured to receive a different one of the at least P forward link signals from the P gateway terminals, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the at least P forward link signals from the P gateway terminals, in order to provide the at least P forward link signals to the plurality of transmit switches, according to the first gateway switching pattern, and each of the at least P forward link signals is sequentially switched into fixed location beams according to the first beam group transmit switching pattern.

19. The satellite communication system of claim 18, wherein the gateway switch structure reverts from sequentially switching the at least Q forward link signals to sequentially switching the at least P forward link signals, as result of disappearance of rain fade making at least one gateway terminal available again.

20. The satellite communication system of claim 11 having a return link capability in addition to forward link capability,

wherein the satellite further comprises a plurality of receive switches coupled to the inputs of the plurality of receivers;

wherein each receive switch in the plurality of receive switches is configured to sequentially switch return link signals from fixed location beams into a receiver according to a beam group receive switching pattern;

wherein prior to time T1, the return link signals from multiple fixed location beams are sequentially switched into the plurality of receivers according to a first beam group receive switching pattern, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the return link signals to at least P transmitters in the plurality of transmitters according to the first gateway switching pattern, and the at least P transmitters are each configured to transmit a different one of the return link signals to one of the P gateway terminals; and

wherein after time T1 and before time T2, the return link signals from multiple fixed location beams are sequentially switched into the plurality of receivers according to a second beam group receive switching pattern, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the return link signals to at least Q transmitters in the plurality of transmitters according to the second gateway switching pattern, and the at least Q transmitters are each configured to transmit a different one of the return link signals to one of the Q gateway terminals.

21. A satellite having a forward link capability comprising:

a plurality of receivers having inputs and outputs;

a plurality of transmitters having inputs and outputs, the inputs of the plurality of transmitters coupled to the outputs of the plurality of receivers;

a plurality of transmit switches coupled to the outputs of the plurality of transmitters;

wherein each transmit switch in the plurality of transmit switches is configured to sequentially switch a forward link signal into multiple fixed location beams according to a beam group transmit switching pattern;

a gateway switch structure coupled to at least one of;

(a) the inputs of the plurality of receivers, (b) the outputs of the plurality receivers and the inputs of the plurality of transmitters, or (c) the outputs of the plurality of transmitters;

a beam switch controller coupled to the plurality of transmit switches and to the gateway switch structure, the beam switch controller configured to store one or more beam group transmit switching patterns and one or more gateway switching patterns;

wherein prior to a time T1, at least P receivers in the plurality of receivers are each configured to receive a different one of at least P forward link signals from P gateway terminals, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the at least P forward link signals from the P gateway terminals, in order to provide the at least P forward link signals to the plurality of transmit switches, according to a first gateway switching pattern, and each of the at least P forward link signals is sequentially switched into fixed location beams according to a first beam group transmit switching pattern;

wherein after time T1 and before a time T2, at least Q receivers in the plurality of receivers are each configured to receive a different one of at least Q forward link signals from Q gateway terminals, and in the duration of one frame, the gateway switch structure is configured to sequentially switch the at least Q forward link signals from the Q gateway terminals, in order to provide the at least Q forward link signals to the plurality of transmit switches, according to a second gateway switching pattern, and each of the at least Q forward link signals is sequentially switched into fixed location beams according to a second beam group transmit switching pattern;

wherein P and Q are both non-zero, positive integers, and Q<

P; and

wherein the first and second gateway switching patterns are different.

22. The satellite of claim 21 wherein the beam switch controller is configured to receive the one or more beam group transmit switching patterns and the one or more gateway switching patterns using an in-band uplink signal.

23. The satellite of claim 21 wherein the beam switch controller is configured to receive the one or more beam group transmit switching patterns and the one or more gateway switching patterns using an out-of-band uplink signal.