Whether driving to work or cruising through the countryside, people dont flip radio channels anymore. Satellite radio provides uninterrupted services to millions of listeners around the world. As the name suggests, satellite radio uses the technology of satellites to deliver audio signals. Satellite radio signals are broadcast in digital form, which a quality of reception that matches that of audio CDs. Satellite radios receive signals that are broadcast by communications satellites. These signals cover a wider area than normal radio signals. Satellite radio functions in any location where there is a line of sight between the antenna and the satellite. The most powerful broadcasts are accessible over 100 miles from the source. Satellite radio technology requires access to a commercial satellite for transmitting signals and are therefore commercial business entities. In 1992, the U.S. Federal Communications Commission (FCC) allocated the ""S"" band (2.3 GHz) for nationwide broadcasting of satellite-based Digital Audio Radio Service (DARS). XM and Sirius are two services that provide satellite radio broadcasts all over the United States. Satellite radio signals are strong and do not require a satellite dish to receive it. The key components of a satellite radio infrastructure are satellites, ground repeaters and radio receivers. A radio receiver has an electronic serial number or Radio ID to identify it. An authorization code is needed to activate a unit. Most services also include free to air channels. These systems are proprietary, using different codecs for audio data compression, encryption and conditional access. Satellite radio also transmits program-associated data (PAD), with an artists name and the title of each song. Major car manufacturers install satellite radio receivers in some of their models. Several models of portable satellite radio receivers are available from electronic firms. Since satellite radio is still in its infant stage, it is inevitable that the technology will continue to improve. In view of its inherent advantages, satellite radios are likely to grow in popularity and become a common household purchase in the near future. |
