Satellite system and method of deploying same

• US 6,257,526 B1
• Filed: 11/09/1998
• Issued: 07/10/2001
• Est. Priority Date: 11/09/1998
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Inventors: Chang, Donald C. D., Wang, Arthur W., Yung, Kar W., Mayfield, William W., Cheng, David C., Novak, John III, Taormina, Frank
• Primary Examiner(s): Jordan, Charles T.
• Assistant Examiner(s): JAKEL, KEVIN W
• Application Number:
  US09/188,440
• Time in Patent Office: 974 Days
• Field of Search: 244/158.R
• US Class Current: 244/158.4
• CPC Class Codes: H04B 7/195 Non-synchronous stations

Abstract

A satellite communication system has a first deployment of a plurality of satellites deployed in a medium earth orbit and two later deployments of a plurality of satellites deployed in the medium earth orbit. The first deployment is spaced so that the second deployment may be easily deployed and interleaved into the first deployment. A ground terminal is used for communicating with the satellites in the first and second deployments.

Claims

1. A satellite constellation comprising:

a first deployment of a plurality of position-adjustable satellites deployed in a medium earth orbit;

the first deployment of satellites having a first configuration corresponding to an initial operation configuration having orbital voids; and

a second deployment of a plurality of position-adjustable satellites deployed in the medium earth orbit in said orbital voids.

2. A satellite constellation as recited in claim 1 wherein said medium earth orbit is substantially about 15000 km above the earth.

3. A satellite constellation as recited in claim 1 wherein said satellites communicate at c/ku/ka bands.

4. A satellite constellation as recited in claim 1 wherein said satellites use the same frequencies as geostationary satellites.

5. A satellite constellation as recited in claim 1 wherein said first plurality of satellites and said second plurality of satellites are deployed on an equatorial plane.

6. A satellite constellation as recited in claim 1 further comprising a third deployment of satellites deployed on an orbit inclined with respect to the equatorial plane.

7. A method of deploying a satellite system comprising the steps of:

deploying a first plurality of satellites into medium earth orbit into a first configuration;

adjusting the first plurality of satellites to a second configuration having orbital voids;

deploying a second plurality of satellites into medium earth orbit, said first plurality and said second plurality together forming a third configuration.

8. A method of deploying a satellite system as recited in claim 7 wherein said step of deploying a first plurality of satellites comprises the step of deploying a first plurality of satellites into medium earth orbit in a single launch.

9. A method of deploying a satellite system as recited in claim 7 wherein said step of deploying a first plurality of satellites into medium earth orbit comprises the step of deploying a first plurality of satellites into medium earth orbit at an altitude of in the range of about 10000 km to about 17000 km.

10. A method of deploying a satellite system as recited in claim 9 wherein said step of deploying a first plurality of satellites into medium earth orbit comprises the step of deploying a first plurality of satellites into medium earth orbit at an altitude of about 15000 km.

11. A method of deploying a satellite system as recited in claim 7 wherein the step of adjusting comprises the step of shifting the first plurality of satellites within the same orbit.

12. A satellite constellation providing semi-global coverage, comprising:

at least four satellites in a medium earth orbit in the equatorial plane.

13. The satellite constellation of claim 12, wherein the medium earth orbit is at an altitude of at least 10000 km, and said at least four satellites are deployed to provide a coverage of at least 0 degrees elevation angle for a latitude of about 39 degrees.

14. satellite constellation of claim 12 wherein the medium earth orbit is at an altitude of at least 10000 km, and said at least four satellites comprise eight satellites which are deployed to provide a coverage of at least about 10 degrees elevation angle for a latitude of about 55 degrees.

15. The satellite constellation of claim 12, wherein the medium earth orbit is at an altitude of about 15000 km, and said at least four satellites comprise twelve said satellites deployed to provide a coverage of at least 10 degrees elevation angle for a latitude of about 63 degrees.

16. The satellite constellation of claim 12 wherein the medium earth orbit is at an altitude of about 15000 km, and said at least four satellites comprise eight satellites deployed to provide a coverage of at least about 10 degrees elevation angle for a latitude of about 60 degrees.

17. A method of deploying a satellite constellation in phased deployments in response to demand for more capacity, comprising:

first deploying at least four satellites in a medium earth orbit in the equatorial plane to provide semi-global coverage; and

subsequently deploying, responsive to demand for greater capacity, at least a second plurality of satellites into the same medium earth orbit as the at least four satellites, each satellite of said second plurality of satellites being interleaved between adjacent ones of said at least four satellites.

18. The method of claim 17, wherein the step of first deploying comprises launching said at least four satellites simultaneously.

19. The method of claim 18, wherein the step of subsequently deploying comprises launching said at least a second plurality of satellites simultaneously.

20. The method of claim 17, wherein the step of subsequently deploying comprises launching said at least a second plurality of satellites simultaneously.

21. The method of claim 20, further comprising deploying at least one additional plurality of satellites in a medium earth orbit in a plane different from the plane of said at least four satellites.

22. The method of claim 17, further comprising at least one additional deployment of an additional plurality of satellites in an inclined medium earth orbit.

23. The method of claim 22, wherein the step of additional deployment comprises launching said additional plurality of satellites simultaneously.

24. The method of claim 17, further comprising adjusting the position of at least one satellite from the group consisting of said at least four satellites and said at least a second plurality of satellites by east/west station keeping.