Patent ID: 6512920
Filing Date: 2003-01-28
Classification: H04B,H04W

Abstract:
A satellite communications system using a plurality of satellites which are arranged on at least one non-stationary orbit, wherein a plurality of satellites on a non-stationary orbit emit beams to form a plurality of coverage areas covering a circumference of the earth and a station located in a coverage area formed by a satellite communicates with the satellite using an established communication link,each of the satellites comprising: a ground communication section for communicating with stations located in the coverage areas on the earth; an intersatellite communication section for communicating with other satellites through intersatellite communications links; and a controller controlling the ground and intersatellite communication sections to perform a handover process, wherein in a first satellite forming a coverage area in which the station is located, a first controller calculates a handover start time at which the handover process should be started for the station, and controls the intersatellite communication section so as to transmit a control signal having a handover completion time added thereto to an adjacent satellite that is to be a handover destination satellite, wherein the handover completion time is calculated from the handover start time, and in a second satellite receiving the control signal having the handover completion time added thereto from the first satellite, a second controller performs the handover process by establishing a new communication link to the station before the handover completion time.