Satellite digital radio is a radio system, which is specially designed for car radios. The operation of the satellite digital radio is that satellite receives the data generated by uplink station, amplify this data and send it back through special spot beam not only to fixed but also to mobile and portable receivers. complementary terrestrial transmitter may be necessary, because in big cities high rise buildings may block the signals from the satellites. In this seminars, an attempt is made to explain the different existing satellite systems, it’s working and key technologies used.
The conversion of analog to digital offers a wealth of benefits not available from AM or FM. The new digital service will offer two channel stereo sound and greatly increased frequency response in audio quality comparable to today’s analog FM.In addition, digital will greatly enhance terrestrial radio robustness, which is the ability to withstand factors such as multipath fading, environmental noise and impulse noise interference from nearby radio broad cast signals and terrain blockage for FM, as well as signal structure like reinforce concrete highway overpasses for AM.