ACQUISITION SYSTEM FOR THE SDMA/TDMA SATELLITE COMMUNICATION SYSTEM

摘要

An acquisition system for the SDMA/TDMA satellite communication system in which a synchronization signal receiving time slot and a plurality of data signal receiving time slots for communication between predetermined groups of earth stations and between the earth stations of each group are changed over based on timing signal in a satellite. An acquisition signal having a plurality of kinds of signals of different types is transmitted from the earth station, with its transmit time slot being shifted in a first sweep mode and, when one part of the acquisition signal is transmitted, with its transmit time slot being shifted in a second sweep mode, whereby a control is made to obtain synchronization of the earth station with the satellite so that the plurality of kinds of signals in the acquisition signal may be received in predetermind modes. Further, an acquisition control can be effectively achieved in the case where the SN ratio of the received acquisition signal is extremely deteriorated or where it is necessary to prevent disturbing other earth station of the same group of earth stations which has already accessed the satellite.