摘要 |
A multiple access satellite communication system in which a plurality of mini-earth stations each transmit data packets to hub earth station via a satellite over an inbound channel, while the hub station transmits to the mini-earth stations in a broadcast mode over outbound channels. Each mini-earth station selectively uses a fixed assignement access method, random access method, and demand assignment access method, depending on the frequency of the transmission from a terminal connected thereto, the amount of transmitted data, and whether or not the transmission from the terminal is periodic. The hub station outputs a reception response signal to the outbound channels by determining whether or not a conflict of data packets or a transmission error has occurred on the inbound channels. Packets for re-transmission are sent out to the inbound channels by the demand assignment access method at all times, with no regard to the access method used at the time of transmission.
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