Ring architecture for an optical satellite communication network with passive optical routing

• US 6,912,075 B1
• Filed: 05/17/1999
• Issued: 06/28/2005
• Est. Priority Date: 05/17/1999
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: The DIRECTV Group, Inc. (AT&T, Inc.)
• Inventors: Ionov, Stanislav I., Valley, George C.
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US09/313,428
• Time in Patent Office: 2,234 Days
• Field of Search: 359/172, 359/152, 359/119, 359/127, 359/173, 359/174, 370/310
• US Class Current: 398/126
• CPC Class Codes: H04B 10/118 specially adapted for satellite communication

Abstract

A node for satellite system communications between a ground station and a satellite includes a fiber optic bus on the satellite. An optical drop is coupled to the bus. The optical drop resolves an optical signal destined to the given satellite from the optical bus. An uplink and downlink receive and transmit communications from a ground terminal. A router is coupled to the optical drop and the uplink and downlink. An address reader and a table are used by the router to determine the destination of the received RF signals. The received RF signals are converted to optical signals by an optical source. The optical source has a wavelength that corresponds with the destination satellite. The optical signals are transmitted to an adjacent satellite by an optical transmitter such as a transmitting telescope.

Claims

1. A node for a satellite system for communications between a ground station and a satellite comprising:

an RF uplink receiving a first RF signal from the ground station and converting said first RF signal to a first electrical signal;

an RF downlink for generating a second RF signal and transmitting the second RF signal to the ground station;

a receiving telescope;

an optical bus coupled to said receiving telescope, said optical bus having a plurality of optical signals from said receiving telescope;

an optical interface coupled to said optical bus, said optical interface resolving a predetermined optical signal from said optical bus that is associated with the satellite, said optical interface converting said predetermined optical signal into a second electrical signal; and

a router coupled to said optical interface, said RF uplink and said RF downlink, said router identifying said first electrical signal and routing said first electrical signal to said optical interface or said RF downlink, said router routing said second electrical signal from said optical interface to said RF downlink.

2. A node for a satellite system as recited in claim 1 wherein said optical interface comprises an optical drop coupled to said optical bus, said optical drop resolving said predetermined optical signal from said optical bus, said optical interface converting said first electrical signal into a second optical signal.

3. A node for a satellite system as recited in claim 2 wherein said optical drop comprises one selected from the group consisting of a wavelength division multiplexer, a drop/add filter, and a waveguide grating router.

4. A node for a satellite system as recited in claim 1 wherein said optical interface comprises a receiver, said receiver converting said predetermined optical signal to said second electrical signal.

5. A node for a satellite system as recited in claim 1 wherein said optical interface comprises an optical source coupled to said optical bus for converting said first electrical signal into a second optical signal.

6. A node for a satellite system as recited in claim 1 further comprising a transmitting telescope coupled to said optical bus.

7. A node for a satellite system as recited in claim 1 further comprising an amplifier coupled to said receiving telescope.

8. A node for a satellite system as recited in claim 1 wherein said first RF signal has a header.

9. A node for a satellite system as recited in claim 8 further comprising an address reader.

10. A node for a satellite system as recited in claim 8 further comprising a table.

11. A node for a satellite system as recited in claim 1 wherein the first electrical signal and the second electrical signal comprise a respective first address and second address, said router routing said first electrical signal and said second electrical signal in response to said respective first address and said second address.

12. A communication system comprising:

a ground station;

a first satellite node;

a second satellite node optically coupled to said first satellite node;

a first receiving telescope;

said first satellite node comprising a first optical bus coupled to said first receiving telescope, said first optical bus having a plurality of optical signals from said first receiving telescope;

a first RF uplink receiving a first RF signal from said ground station and converting the first RF signal to a first electrical signal;

a first RF downlink for generating a second RF signal and transmitting the second RF signal to said ground station;

a first optical interface coupled to said first optical bus, said first optical interface resolving a first predetermined optical signal from said first optical bus that is associated with said first satellite node, said first optical interface converting said first predetermined optical signal into a second electrical signal;

a first router coupled to said first optical interface, said first RF uplink and said first RF downlink, said first router identifying said first electrical signal and routing said first electrical signal to said first optical interface or said first RF downlink, said first router routing said second electrical signal to said first RF downlink;

said first optical interface generating a first optical output signal corresponding to said first electrical signal, said first optical interface coupling said first optical output signal to said first optical bus;

a first optical transmitter coupling said first satellite node to said second satellite node;

a second receiving telescope;

said second satellite node comprising a second optical bus coupled to said second receiving telescope, said second optical bus having a plurality of optical signals from said second receiving telescope;

a second RF uplink receiving a third RF signal from said ground station and converting the third RF signal to a third electrical signal;

a second RF downlink for generating a fourth RF signal and transmitting the fourth RF signal to said ground station;

a second optical interface coupled to said second optical bus, said second optical interface resolving a second predetermined optical signal from said second optical bus that is associated with said second satellite node, said second optical interface converting said second predetermined optical signal into a fourth electrical signal; and

a second router coupled to said second optical interface, said second RF uplink and said second RF downlink, said second router identifying said third electrical signal and routing said third electrical signal to said second optical interface or said second RF downlink, said second router routing said fourth electrical signal to said second RF downlink.

13. A communication system as recited in claim 12 wherein said first optical interface resolves a first wavelength from said first optical bus;

said second optical interface resolves a second wavelength, wherein said first wavelength is different from said second wavelength.

14. A communication system as recited in claim 12 wherein said first optical interface comprises an optical drop coupled to said first optical bus, said optical drop resolving said first predetermined optical signal from said first optical bus.

15. A communication system as recited in claim 12 wherein said optical drop comprises one selected from the group consisting of a wavelength division multiplexer, a drop/add filter, and a waveguide grating router.

16. A communication system as recited in claim 12 wherein said first optical interface comprises a receiver, said receiver converting said first predetermined optical signal to said second electrical signal.

17. A communication system as recited in claim 12 wherein said first optical interface comprises an optical source coupled to said first optical bus for converting said first electrical signal into said first optical output signal.

18. A communication system as recited in claim 17 further comprising an optical add coupled to said optical source for coupling said first optical output signal to said first optical bus.

19. A communication system as recited in claim 12 wherein said first satellite node, said second satellite node, and a third satellite node are disposed in a ring.

20. A method of communicating within a satellite communication system comprising the steps of:

receiving a plurality of optical signals from a first satellite;

resolving a first optical signal from the plurality of optical signals;

transmitting the plurality of optical signals minus the first optical signal to another satellite;

converting the first optical signal into an electrical signal,

converting the electrical signal into a corresponding RP signal; and

transmitting the corresponding RF signal to a ground station.

21. A method as recited in claim 20 further comprising the steps of:

receiving a second RF signal;

converting the second RF signal into a second electrical signal;

converting the second electrical signal into a second optical signal;

transmitting the second optical signal to a second satellite.

22. A method as recited in claim 21 further comprising the step of coupling the second optical signal onto an optical bus.

23. A method as recited in claim 21 wherein the step of transmitting the second optical signal comprises the step of coupling the second optical signal into a transmitting telescope.

24. A method as recited in claim 21 wherein the step of transmitting the second optical signal comprises the step of amplifying the second optical signal.

25. A method as recited in claim 20 further comprising:

receiving a second RF signal;

converting the second RF signal into a second electrical signal;

converting the second electrical signal into a third RF signal; and

transmitting the third RF signal to a ground station.

26. A satellite system comprising:

a plurality of satellites disposed in a ring, each of said plurality of satellites communicating optically with an adjacent satellite and communicating using an RF frequency with a ground station, each of said satellites comprising;

a receiving telescope;

an RF uplink receiving a first RF signal from the ground station and converting the first RF signal to a first electrical signal;

an RF downlink generating a second RF signal and transmitting the second RF signal to the ground station;

an optical bus coupled to said receiving telescope, said optical bus having a plurality of optical signals from said receiving telescope;

an optical interface coupled to said optical bus, said optical interface resolving a predetermined optical signal from said optical bus that is associated with the satellite, said optical interface converting said predetermined optical signal into a second electrical signal; and

a router coupled to said optical interface, said RP uplink and said RF downlink, said router identifying said first electrical signal and routing said first electrical signal to said optical interface or said RF downlink, said router routing said second electrical signal from said optical interface to said RF downlink.

27. A satellite system as recited in claim 26 wherein the plurality of satellites comprises at least three satellites.

28. A satellite system comprising:

a plurality of satellites disposed in a ring, each of said satellites receiving a plurality of optical signals from an adjacent satellite and an RF signal from a ground station, each of said satellites resolving a first optical signal from the plurality of optical signals and converting the first optical signal to a first electrical signal, each of said satellites routing the first electrical signal to a downlink, each of said satellites converting the RF signal to a second electrical signal, each of said satellites routing the second electrical signal to an adjacent one of said plurality of satellites through an optical source or to the downlink.

29. A satellite system comprising:

a plurality of satellites disposed in a ring, each of said satellites receiving a plurality of optical signals from an adjacent satellite, and

at least one of said plurality of satellites receiving an RF signal from a ground station, said at least one of said plurality of satellites resolving at least one optical signal from the plurality of optical signals, converting the at least one optical signal to at least one electrical signal, routing the at least one electrical signal to a downlink, converting the RF signal to a second electrical signal, and routing the second electrical signal to a destination.

30. A satellite system as recited in claim 29 wherein the destination is an adjacent one of said plurality of satellites and the second electrical signal is routed through an optical source as a second optical signal.

31. A satellite system as recited in claim 29 wherein the destination is the downlink.