Space communications system
Satellite Telecommunications Systems - Link architectures

If a user's terminal is connected to its counterpart via a mixed network, comprising terrestrial and satellite links, the network operator's task is to route the signals generated by the transmitting terminal (voice or data signals linked to a computer or video camera) to their destination. From the earth station, the signals use a radio medium (with a carrier wave) to reach one or more receiving stations, with the satellite acting as a radio relay.

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