A communications satellite is an artificial satellite stationed in space for the purposes of telecommunications. Satellite systems deliver data from a satellite to a consumer. Telecommunication using satellite systems find applications in radio, telegraphy, television, telephone, data communication and computer networking. The first satellite television signal was relayed from Europe to the Telstar satellite over North America in 1962. The first geosynchronous communication satellite, Syncom 2 was launched in 1963. The world's first commercial communication satellite, called Early Bird, was launched into synchronous orbit on April 6, 1965. Satellites used for conveying television signals are usually in an elliptical or geo-stationary orbit, 37,000 km (22,300 miles) above the earths equator. Satellite television, just as any other communication relayed by satellite, requires a transmittal antenna located at an uplink facility. A telecommunication system comprises of a transmitter, a medium and a channel imposed upon the medium and a receiver. The transmitter is a device that transforms or encodes the message into a physical phenomenon known as the signal. The transmission medium, by its physical nature, is likely to modify or degrade the signal on its path from the transmitter to the receiver. The receiver has a decoding mechanism capable of recovering the message within certain limits of signal degradation. There are three primary types of satellite television usage namely reception direct by the viewer, reception by local television affiliates or reception by head ends for distribution across terrestrial cable systems. Direct to the viewer reception includes direct broadcast satellite or DBS and television receive-only or TVRO, both of which are used for homes and businesses including hotels. Satellite television system has revolutionized the medium of television and its access to the customer. In many parts of the world, satellite television services supplement older terrestrial signals, providing a wider range of channels and services, including subscription-only services. |
