Satellites are nothing but relay stations in space for the transmission of Voice, Video and Data complementing the existing land based communication infrastructure. Sputnik 1 is the first satellite launched by Soviet Union on October 4,1957 followed by Telstar, a communication satellite launched by AT&T in 1962.

The first geostationary satellite Syncom3, launched in 1964 was useful in television coverage of Olympics. Intelsat 1 was launched in 1964 and it was the first geostationary satellite for telecommunication over the Atlantic Ocean, followed by launch of various satellites for Broadcast applications. Active Satellites, which amplify and retransmit the signal from the earth have several advantages over the passive satellites as they require lower power earth station, less costly and controlled by operators from ground. This led to Direct To Home television broadcasting and VSAT based data communications using small antenna systems deployed on rooftops and finally personal communications of voice and data for anyone from anywhere and anytime with Mobile Satellite services.