Satellite Communications:-

The technology is actually a radio in the sky. Satellite stations with transmitting and receiving antenna are launched into orbit by rockets where they receive signal from transmitting stations on earth and relay these signals back to earth stations. Unique aspects of communication satellites:

1. The technology provides for a large communications capacity. Through the use of microvoice grade channels can be placed on a satellite station.

2. The satellite has the capacity for broadcast transmission. The transmitting antenna can send signals to wide geographical applications such as Electronic distributed system find the capability quite useful.

3. Transmission cost is independent of distance between the earth & station. It has no difference if two sites are 100 or 1000 miles apart.

4. The stations experience a significant signed propagation delay. Since, satellites are positioned about 22,300 miles about earth, the transmission has to travel to the satellite and return to the receiving earth station. Thus delay may affect certain applications or software systems.

5. The broad cast aspect of satellite communications may present security problems since all stations under the satellite antenna can receive the broadcasts consequently. Transmissions are often changed (encrypted) for satellite channels.