Q 2.13 How do satellites communicate with the Earth?
Satellites communicate with the Earth over radio links at frequencies assigned by the operator. These frequencies are in line with the prevailing Radio Regulations.
Transparent transponders receive signals, amplify and retransmit the received signal on a different frequency. Advanced repeaters can extract information and retransmit them in a different format better suited for the downlink. Such satellites can also route the signals intelligently to make the best use of satellite power and spectrum.