FREQUENCY SHARING FOR SATELLITE COMMUNICATION SYSTEM

摘要

A communication system and method for sharing a common communication frequency, without interfering with a second communication system which has a plurality of satellites operating in geostationary orbits (GO) and ground stations (GS) which communicate with the satellites (GEO) on the common communication frequency. Conventional geostationary satellites broadcast in C and Ku bands. Ground stations (GS) which receive these signals must have their antennas pointed toward the plane of the equator (EQ). Satellites (10) which occupy inclined orbits (LO) and communicate with terrestrial terminals (12) propagate beams of energy that do not intersect the plane of the Earth's equator. Terrestrial terminals (12) in the northern hemisphere communicate with a satellite (10) only when the sub-satellite point of the satellite (10) is at a latitude more northerly than the terrestrial terminal (12). Terrestrial terminals (12) in the southern hemisphere communicate with a satellite (10) only when the sub-satellite point of the satellite (10) is at a latitude more southerly than the terrestrial terminal (12). The spatial isolation of signals achieved by this novel pointing method insures that both the geostationary and inclined orbit satellite systems do not interfere with each other. 00000