Placement of Gateways Away from Service Beams

• US 20090081946A1
• Filed: 08/06/2008
• Published: 03/26/2009
• Est. Priority Date: 09/26/2006
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Wilson, Robert, Jaska, Kristi, Miller, Mark J., Dankberg, Mark D., Hart, Steven R.
• Granted Patent: US 8,855,552 B2
• Time in Patent Office: Days
• US Class Current: 455/3.20
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18543 for adaptation of transmission parameters, e.g. power control for detecting or preventing errors in the information received H04L1/00
• CPC Class Codes: H04B 7/18582 Arrangements for data linking, i.e. for data framing, for error recovery, for multiple access

Abstract

A method is presented for transmitting data in a satellite system having multiple spot beams comprising (1) sending a broadband signal in a forward direction from a gateway terminal to a communications satellite for relay to at least one subscriber terminal, (2) receiving the broadband signal at the communications satellite, wherein the communications satellite comprises a bent pipe repeater having a plurality of satellite-based transmission amplifiers, (3) using one of the plurality of satellite-based transmission amplifiers to amplify the broadband signal and no other broadband signal from the gateway terminal, to produce an amplified broadband signal, (4) sending the amplified broadband signal as one of a plurality of service spot beams to the at least one subscriber terminal, and (5) receiving and retrieving data from the amplified broadband signal at the at least one subscriber terminal.

Claims

1. A method for communicating data in a multibeam satellite system utilizing frequency re-use comprising:

establishing service beams including uplink service beams and downlink service beams between a satellite and a plurality of subscriber terminals, each downlink service beam being associated with a different service beam coverage area, to form a plurality of service beam coverage areas;

wherein a plurality of the uplink service beams are transmitted to the satellite by re-using at least one common uplink frequency channel, and a plurality of the downlink service beams are transmitted from the satellite by re-using at least one common downlink frequency channel;

establishing at least one uplink feeder beam and at least one downlink feeder beam between the satellite and a gateway terminal, the at least one downlink feeder beam being associated with a feeder beam coverage area separated from the plurality of service beam coverage areas, the at least one uplink feeder beam being received at the satellite to form a plurality of the downlink service beams, a plurality of the uplink service beams being received at the satellite to form the at least one downlink feeder beam; and

wherein the at least one uplink feeder beam is transmitted to the satellite by further re-using the at least one common uplink frequency channel, and the at least one downlink feeder beam is transmitted from the satellite by further re-using the at least one common downlink frequency channel.

2. The method of claim 1 wherein the at least one uplink feeder beam comprises multiple uplink feeder beams, and the at least one downlink feeder beam comprises multiple downlink feeder beams, wherein a plurality of the uplink feeder beams are transmitted to the satellite by yet further re-using the at least one common uplink frequency channel, and a plurality of the downlink feeder beams are transmitted from the satellite by yet further re-using the at least one common downlink frequency channel.

3. The method of claim 1 wherein the at least one uplink feeder beam comprises 4 carriers, wherein the at least one common uplink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each of the 4 carriers is transmitted using one of the 4 unique combinations of frequency and polarization.

4. The method of claim 1 wherein the at least one downlink feeder beam comprises 4 carriers, wherein the at least one common downlink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each of the 4 carriers is transmitted using one of the 4 unique combinations of frequency and polarization.

5. The method of claim 1 wherein each uplink service beam comprises 1 carrier, wherein the at least one common uplink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each carrier of an uplink service beam is transmitted using one of the 4 unique combinations of frequency and polarization.

6. The method of claim 1 wherein each downlink service beam comprises 1 carrier, wherein the at least one common downlink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each carrier of a downlink service beam is transmitted using one of the 4 unique combinations of frequency and polarization.

7. The method of claim 1 wherein the at least one common uplink frequency channel includes a 500 MHz frequency channel.

8. The method of claim 1 wherein the at least one common downlink frequency channel includes a 500 MHz frequency channel.

9. A multibeam satellite system utilizing frequency re-use comprising:

a plurality of subscriber terminals capable of establishing service beams including uplink service beams and downlink service beams between the subscriber terminals and a satellite, each downlink service beam being associated with a different service beam coverage area, to form a plurality of service beam coverage areas;

wherein a plurality of the uplink service beams are suited for transmission to the satellite by re-using at least one common uplink frequency channel, and a plurality of the downlink service beams are suited for transmission from the satellite by re-using at least one common downlink frequency channel;

a gateway terminal capable of establishing at least one uplink feeder beam and at least one downlink feeder beam between the gateway terminal and the satellite, the at least one downlink feeder beam being associated with a feeder beam coverage area separated from the plurality of service beam coverage areas, the at least one uplink feeder beam to be received at the satellite to form a plurality of the downlink service beams, a plurality of the uplink service beams to be received at the satellite to form the at least one downlink feeder beam; and

wherein the at least one uplink feeder beam is suited for transmission to the satellite by further re-using the at least one common uplink frequency channel, and the at least one downlink feeder beam is suited for transmission from the satellite by further re-using the at least one common downlink frequency channel.

10. The apparatus of claim 9 wherein the at least one uplink feeder beam comprises multiple uplink feeder beams, and the at least one downlink feeder beam comprises multiple downlink feeder beams, wherein a plurality of the uplink feeder beams are suited for transmission to the satellite by yet further re-using the at least one common uplink frequency channel, and a plurality of the downlink feeder beams are suited for transmission from the satellite by yet further re-using the at least one common downlink frequency channel.

11. The apparatus of claim 9 wherein the at least one uplink feeder beam comprises 4 carriers, wherein the at least one common uplink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each of the 4 carriers is transmitted using one of the 4 unique combinations of frequency and polarization.

12. The apparatus of claim 9 wherein the at least one downlink feeder beam comprises 4 carriers, wherein the at least one common downlink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each of the 4 carriers is transmitted using one of the 4 unique combinations of frequency and polarization.

13. The apparatus of claim 9 wherein each uplink service beam comprises 1 carrier, wherein the at least one common uplink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each carrier of an uplink service beam is transmitted using one of the 4 unique combinations of frequency and polarization.

14. The apparatus of claim 9 wherein each downlink service beam comprises 1 carrier, wherein the at least one common downlink frequency channel comprises two frequency channels, each of the two frequency channels capable of being separated by right hand circular polarization (RHCP) and left hand circular polarization (LHCP), to form 4 unique combinations of frequency and polarization, and wherein each carrier of a downlink service beam is transmitted using one of the 4 unique combinations of frequency and polarization.

15. The apparatus of claim 9 wherein the at least one common uplink frequency channel includes a 500 MHz frequency channel.

16. The apparatus of claim 9 wherein the at least one common downlink frequency channel includes a 500 MHz frequency channel.

17. A system for communicating data in a multibeam satellite system utilizing frequency re-use comprising:

means for establishing service beams including uplink service beams and downlink service beams between a satellite and a plurality of subscriber terminals, each downlink service beam being associated with a different service beam coverage area, to form a plurality of service beam coverage areas;

wherein a plurality of the uplink service beams are transmitted to the satellite by re-using at least one common uplink frequency channel, and a plurality of the downlink service beams are transmitted from the satellite by re-using at least one common downlink frequency channel;

means for establishing at least one uplink feeder beam and at least one downlink feeder beam between the satellite and a gateway terminal, the at least one downlink feeder beam being associated with a feeder beam coverage area separated from the plurality of service beam coverage areas, the at least one uplink feeder beam being received at the satellite to form a plurality of the downlink service beams, a plurality of the uplink service beams being received at the satellite to form the at least one downlink feeder beam; and

wherein the at least one uplink feeder beam is transmitted to the satellite by further re-using the at least one common uplink frequency channel, and the at least one downlink feeder beam is transmitted from the satellite by further re-using the at least one common downlink frequency channel.

18. A method for operating a multibeam satellite system utilizing subscriber terminal and gateway terminal positioning comprising:

positioning a plurality of subscriber terminals within a plurality of service beam coverage areas, the subscriber terminals capable of establishing uplink service beams and downlink service beams between the subscriber terminals and a satellite, the downlink service beams being associated with the plurality of service beam coverage areas;

wherein a plurality of the uplink service beams are to be transmitted to the satellite by re-using at least one common uplink frequency channel, and a plurality of the downlink service beams are to be transmitted from the satellite by re-using at least one common downlink frequency channel;

positioning a gateway terminal within a feeder beam coverage area, the gateway terminal capable of establishing an uplink feeder beam and a downlink feeder beam between the gateway terminal and the satellite, the downlink feeder beam being associated with the feeder beam coverage area, the feeder beam coverage area being located apart from the plurality of service beam coverage areas, the uplink feeder beam to be received at the satellite to form a plurality of the downlink service beams, a plurality of the uplink service beams to be received at the satellite to form the downlink feeder beam; and

wherein the uplink feeder beam is to be transmitted to the satellite by further re-using the at least one common uplink frequency channel, and the downlink feeder beam is to be transmitted from the satellite by further re-using the at least one common downlink frequency channel.

19. The method of claim 18 wherein the gateway terminal is one of a plurality of gateway terminals, each gateway terminal being positioned within a different one of a plurality of feeder link coverage areas.

20. The method of claim 19 wherein each of the plurality of gateway terminals is separated from every other one of the plurality of gateway terminals by a minimum distance of 400 kilometers.

21. The method of claim 20 wherein each of the plurality of gateway terminals is placed within a distance of 50 kilometers from an optical fiber network connection.

22. The method of claim 21 wherein each of the plurality of gateway terminals is placed at a location where overall rain fade at the at least one common uplink frequency channel is less than a particular amount of fading for a specified percentage of the time.

23. The method of claim 22 wherein the particular amount of fading is 10 dB of fading, and the specified percentage of time is 99.99% of the time.

24. An apparatus for multibeam satellite communications adopting subscriber terminal and gateway terminal positioning comprising:

a plurality of subscriber terminals positioned within a plurality of service beam coverage areas, the subscriber terminals capable of establishing uplink service beams and downlink service beams between the subscriber terminals and a satellite, the downlink service beams being associated with the plurality of service beam coverage areas;

wherein a plurality of the uplink service beams are to be transmitted to the satellite by re-using at least one common uplink frequency channel, and a plurality of the downlink service beams are to be transmitted from the satellite by re-using at least one common downlink frequency channel;

a gateway terminal positioned within a feeder beam coverage area, the gateway terminal capable of establishing an uplink feeder beam and a downlink feeder beam between the gateway terminal and the satellite, the downlink feeder beam being associated with the feeder beam coverage area, the feeder beam coverage area being located apart from the plurality of service beam coverage areas, the uplink feeder beam to be received at the satellite to form a plurality of the downlink service beams, a plurality of the uplink service beams to be received at the satellite to form the downlink feeder beam; and

wherein the uplink feeder beam is to be transmitted to the satellite by further re-using the at least one common uplink frequency channel, and the downlink feeder beam is to be transmitted from the satellite by further re-using the at least one common downlink frequency channel.

25. The apparatus of claim 24 wherein the gateway terminal is one of a plurality of gateway terminals, each gateway terminal being positioned within a different one of a plurality of feeder link coverage areas.

26. The apparatus of claim 25 wherein each of the plurality of gateway terminals is separated from every other one of the plurality of gateway terminals by a minimum distance of 400 kilometers.

27. The apparatus of claim 26 wherein each of the plurality of gateway terminals is placed within a distance of 50 kilometers from an optical fiber network connection.

28. The apparatus of claim 27 wherein each of the plurality of gateway terminals is placed at a location where overall rain fade at the at least one common uplink frequency channel is less than a particular amount of fading for a specified percentage of the time.

29. The apparatus of claim 28 wherein the particular amount of fading is 10 dB of fading, and the specified percentage of time is 99.99% of the time.

30. A system for operating a multibeam satellite system utilizing subscriber terminal and gateway terminal positioning comprising:

means for positioning a plurality of subscriber terminals within a plurality of service beam coverage areas, the subscriber terminals capable of establishing uplink service beams and downlink service beams between the subscriber terminals and a satellite, the downlink service beams being associated with the plurality of service beam coverage areas;

wherein a plurality of the uplink service beams are to be transmitted to the satellite by re-using at least one common uplink frequency channel, and a plurality of the downlink service beams are to be transmitted from the satellite by re-using at least one common downlink frequency channel;

means for positioning a gateway terminal within a feeder beam coverage area, the gateway terminal capable of establishing an uplink feeder beam and a downlink feeder beam between the gateway terminal and the satellite, the downlink feeder beam being associated with the feeder beam coverage area, the feeder beam coverage area being located apart from the plurality of service beam coverage areas, the uplink feeder beam to be received at the satellite to form a plurality of the downlink service beams, a plurality of the uplink service beams to be received at the satellite to form the downlink feeder beam; and

wherein the uplink feeder beam is to be transmitted to the satellite by further re-using the at least one common uplink frequency channel, and the downlink feeder beam is to be transmitted from the satellite by further re-using the at least one common downlink frequency channel.