Communications Technology Handbook, 2nd Edition

31 Satellite systems

Satellite communications systems are based on the relay systems that have developed for terrestrial communications, except that the receiver/transmitter, known in this case as the transponder, is located in space.

In spite of the high costs involved, the flexibility and advantages gained allow satellites to make a valuable contribution to worldwide communications.

All the propagation parameters are well defined and can be accurately modelled mathematically. A single satellite can provide communications coverage for almost one-third of the earth’s surface, using much less radio frequency power than would be required for an equivalent terrestrial system. Even though the signal attenuation due to the long path lengths is high, ...