Patent ID: 6226494
Filing Date: 2001-05-01
Classification: H04B

Abstract:
A satellite communication system, comprising:a plurality of satellites in non-geostationary earth orbit in one or more predetermined orbital planes and distributed in an arrangement with distances between satellites sufficient such that, at times, all satellites are out of range of an antenna beam coverage region of a non-tracking antenna of an earth-based station; andan earth-based satellite communication station to establish a temporary communication link with the plurality of satellites wherein the earth-based station is initially out of communication with the plurality of satellites, the earth-based station comprising:a data storage area to collect and temporarily store data for subsequent transmission to a detected one of the plurality of satellites;a non-tracking directional antenna having a fixed aperture with an antenna beam coverage region and positioned at a fixed azimuth and elevation;a satellite detection system to detect when one of the plurality of satellites passes through the antenna beam coverage region, the satellite detection system generating an indicator that one of the plurality of satellites has been detected within the antenna beam coverage region;a receiver coupled to the antenna to receive radio transmissions from the detected satellite when the satellite passes through the antenna beam coverage region; anda transmitter coupled to the antenna to transmit the stored data to the detected satellite when the satellite passes through the antenna beam coverage region, the receiver and transmitter communicating with the detected satellite while the detected satellite is within the antenna beam coverage region and not communicating with any of the plurality of satellites when the detected satellite passes out of the antenna beam coverage region, such that the temporary communication link between the earth-based station and the plurality of satellites is terminated until the satellite detection system subsequently detects when one of the plurality of satellites passes through the antenna beam coverage region.