Satellite communication system employing a combination of time slots and orthogonal codes

1. A satellite communication system for communicating between a plurality of user terminals comprising:

a satellite constellation wherein each satellite of said constellation provides multiple beams;

a plurality of user terminals that communicate with each other via satellites of said constellation;

at least one gateway connected to a PSTN and communicating with at least one user terminal over the constellation wherein each of said user terminals within a given frequency band is distinguished from another of said user terminals employing a combination of time slots and orthogonal codes;

wherein each of said user terminals is equipped to initiate or receive or terminate packet data messages;

wherein each of said user terminals is handed off from one beam of a satellite to another beam of said satellite; and

wherein said hand off is predicated on signal strength determined at said plurality of user terminals.

2. A satellite communication system as defined in claim 1 wherein said combination of time slots and orthogonal codes is implemented in a forward and return link.

3. A satellite communication system as defined in claim 2 wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

4. A satellite communication system as defined in claim 1 wherein said satellite constellation comprises a LEO satellite constellation.

5. A satellite communication system as defined in claim 4 wherein said combination of time slots and orthogonal codes is implemented in a forward and return link.

6. The constellation as defined in claim 5 wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

7. A satellite communication system as defined in claim 1 wherein said satellite constellation comprises a MEO satellite constellation.

8. The constellation as defined in claim 7 wherein said combination of time slots and orthogonal codes is implemented in a forward and return link.

9. A satellite communication system as defined in claim 1 wherein said satellite constellation comprises a GEO satellite constellation.

10. The constellation as defined in claim 8 wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

11. The constellation as defined in claim 9 wherein said combination of time slots and orthogonal codes is implemented in a forward and return link.

12. A satellite communication system as defined in claim 11 wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

13. A satellite communication system for communicating with a plurality of user terminals comprising:

a satellite constellation wherein each satellite of said constellation provides multiple beams;

a plurality of user terminals that communicate with each other, a PSTN, or a data network, via satellites of said constellation;

at least one gateway connected to a PSTN and/or a data network and communicating with at least one user terminal over the constellation wherein each of said user terminals within a given frequency band is distinguished from another of said user terminals employing a combination of time slots and orthogonal codes;

wherein each of said user terminals is equipped to initiate or receive or terminate packet data messages; and

wherein each of said user terminals is handed off from one beam of a satellite to another beam of said satellite.

14. A satellite communication system as defined in claim 13 wherein said combination of time slots and orthogonal codes is implemented in a forward and return link.

15. A satellite communication system as defined in claim 14 wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

16. A satellite communication system as defined in claim 13 wherein said satellite constellation comprises a LEO satellite constellation, wherein said combination of lime slots and orthogonal codes is implemented in a forward and return link, and wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

17. A satellite communication system as defined in claim 13 wherein said satellite constellation comprises a MIEO satellite constellation, wherein said combination of time slots and orthogonal codes is implemented in a forward and return link, and wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.

18. A satellite communication system as defined in claim 13 wherein said satellite constellation comprises a GEO satellite constellation, wherein said combination of time slots and orthogonal codes is implemented in a forward and return link, and wherein said forward link comprises orthogonal codes and said return link comprises a combination of time slots and phase shift of one or more pseudo-random codes.