Satellite communication system constituted with primary and back-up multi-beam satellites

• US 8,744,344 B2
• Filed: 05/23/2008
• Issued: 06/03/2014
• Est. Priority Date: 07/23/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Schiff, Leonard N., Miller, David S.
• Primary Examiner(s): Jain, Ankur
• Application Number:
  US12/126,337
• Publication Number:
  US 20090051589A1
• Time in Patent Office: 2,202 Days
• Field of Search: 455/500
• US Class Current: 455/12.1
• CPC Class Codes: H04B 7/18519 Operations control, administration or maintenance

Abstract

A satellite communication system for providing communications between user terminals and gateways constituted with m primary satellites. In one embodiment, n back up satellites are also provided. Further, each satellite, primary or back-up, is equipped to project N/m beams onto and across an area in a loosely-packed array manner. M of the m primary and n back-up satellites collectively create N beam spots to cover the area. Moreover, each sub-area is covered by a beam spot separated from another sub-area covered by another beam spot by one beam width. Each satellite is also equipped to facilitate communication over 1 of m band of frequencies on one beam. AS a result, any of the m primary satellites may be efficiently replaced on demand by a selected one of the n back-up satellites. The gateways and user terminals are configured to communicate signals through or with both or either the primary and back-up satellites.

Claims

1. A satellite communication system comprising:

m primary satellites, each equipped to project N/m beams onto an area, the N/m beams from each primary satellite projected across the area in a loosely-packed array wherein beam spots from any one of the m primary satellites are separated by one beam width, wherein N is a total number of beams projected over the area by the m primary satellites and m is an integer greater than 1; and

n back-up satellites, each equipped, disposed, and configured to project N/m beams onto the area such that beam spots from any one of the n back-up satellites are positioned within gaps between the beam spots from the m primary satellites, wherein respective ones of the n back-up satellites are configured to respond to failure of a failed primary satellite by angularly redirecting its beams, without moving from an orbital position occupied by the respective ones of the n back-up satellites prior to the failure of the failed primary satellite, to cover the area previously covered by the beams from the failed primary satellite.

2. The satellite communication system of claim 1, wherein the m primary satellites are configured to communicate over different ones of m frequency bands.

3. The satellite communication system of claim 2, wherein the one of the n back-up satellites assumes one of the m frequency bands over which the failed primary satellite had been configured to communicate.

4. The satellite communication system of claim 2, wherein N beam spots from the m primary satellites are projected over the area such that adjacent beam spots facilitate communication over different frequency bands.

5. The satellite communication system of claim 1, wherein the satellite communication system facilitates access by user terminals to a communication network.

6. The satellite communication system of claim 5, wherein the communications network comprises at least one of an Internet or an enterprise Intranet.

7. The satellite communication system of claim 1, wherein n is less than m.

8. The satellite communication system of claim 1, wherein the m primary satellites and the n back-up satellites facilitate communication with at least one of a cellular phone, a wireless handset, a wireless modern, a data transceiver, or a position determination receiver.

9. The satellite communication system of claim 1, wherein each of the N beams comprise a number of sub-beams operating within different frequency bands.

10. The satellite communication system of claim 1, wherein the beams from the n back-up satellites are used to absorb additional transient load during peak demand periods.

11. The satellite communication system of claim 1, wherein the m primary satellites and n backup satellites are configured to perform load balancing between the primary and backup satellites.

12. The satellite communication system of claim 1, wherein every beam spot from any one of the m primary satellites is at least partially non-overlapping with every beam spot from any other of the m primary satellites.

13. A method of satellite communication, the method comprising:

projecting N/m beams from each of m primary satellites onto an area in a loosely-packed array, beam spots from each of the m primary satellites separated by one beam width, wherein N is a total number of beams projected over the area by the m primary satellites and m is an integer greater than 1;

projecting, prior to a failure of one of the m primary satellites, N/m beams from each of n back-up satellites onto the area such that beam spots from any one of the n back-up satellites are positioned within gaps between the beam spots from the m primary satellites;

detecting the failure of the one of the m primary satellites; and

redirecting the N/m beams from one of the n back-up satellites, without moving the one of the n back-up satellites from an orbital position occupied by the one of the n back-up satellites prior to the failure of the one of the m primary satellites that failed, to cover the area previously covered by the beams from the one of the m primary satellites that failed, wherein the redirecting comprises adjusting a projection angle of an antenna on the one of the n back-up satellites.

14. The method of claim 13, further comprising configuring each of the m primary satellites to communicate over a different one of m frequency bands.

15. The method of claim 14, further comprising configuring the one of the n back-up satellites to communicate over a frequency band over which the one of the m primary satellites that failed had been configured to communicate.

16. The method of claim 13, further comprising projecting the N beams from the m primary satellites over the area such that adjacent beam spots facilitate communication over a different one of m frequency bands.

17. The method of claim 13, further comprising projecting a number of sub-beams within each of the N beams, each sub-beam operating within a different frequency band.

18. A non-transitory machine-readable storage medium comprising processor-executable instructions configured to cause a processor to:

project N/m beams from each of m primary satellites onto an area in a loosely-packed array, beam spots from each of the m primary satellites separated by one beam width, wherein N is the a total number of beams projected over the area by the m primary satellites and m is an integer greater than 1;

project, prior to a failure of one of the m primary satellites, N/m beams from each of n back-up satellites onto the area such that beam spots from any one of the n back-up satellites are positioned within gaps between the beam spots from the m primary satellites;

detect the failure of the one of the m primary satellites; and

redirect the N/m beams from one of the n back-up satellites, without moving the one of the n back-up satellites from an orbital position occupied by the one of the n back-up satellites prior to the failure of the one of the m primary satellites that failed, to cover the area previously covered by the beams from the one of the m primary satellites that failed by modifying a projection angle of an antenna on the one of the n back-up satellites.