Method for limiting interference between satellite communications systems

• US 20030034422A1
• Filed: 05/21/2002
• Published: 02/20/2003
• Est. Priority Date: 01/07/2000
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Higgins, Robert P.
• Granted Patent: US 6,866,231 B2
• Time in Patent Office: Days
• US Class Current: 244/158R
• CPC Class Codes: B64G 1/1007 Communications satellites
• CPC Class Codes: B64G 1/1085 Swarms and constellations
• CPC Class Codes: B64G 1/242 Orbits and trajectories
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/195 Non-synchronous stations

Abstract

Boeing achieves satellite diversity by having a large discrimination angle for a MEO constellation of communications satellites to limit interference in the Ku-band with GSO communications systems. Each satellite entering an exclusion zone over a GSO ground station terminates all transmissions to provide EPFD within acceptable limits. The Boeing MEO constellation preferably comprises 20 satellites, 5 in each orbit. The four orbits are inclined at about 57° with respect to the equator. Services include an Integrated Digital Service (IDS) and Backhaul Data Service (BDS) to accommodate the needs of different users.

Claims

1. A method to reduce interference between a GSO satellite and its GSO ground station when operating an NGSO satellite or constellation of satellites orbiting at medium earth orbit (MEO), comprising the step of:

terminating all transmission signals generated on a particular NGSO satellite or emanating from an NGSO ground station in communication with the NGSO satellite when the NGSO satellite is in an exclusion zone defined for a GSO ground station antenna.

2. The method of claim 1 wherein the exclusion zone is from 15°

North to 15°

South latitude.

3. A satellite communications system implementing the method of claim 1.