How do Satellites Work?

The process begins at an earth station–an installation designed to transmit and receive signals from a satellite in orbit around the earth. Earth stations send information in the form of high powered, high frequency (GHz range) signals to satellites which receive and retransmit the signals back to earth where they are received by other earth stations in the coverage area of the satellite. The area which receives a signal of useful strength from the satellite is known as the satellite’s footprint. The transmission system from the earth station to the satellite is called the uplink, and the system from the satellite to the earth station is called the downlink.