Satellite Radio - written by Nevets Notrom

Today,we listen to songs on the radio with complete clarity and high quality - thanks to the invention of the satellite radio which considered to be the biggest improvement in broadcasting since FM has been introduced.

A listener will never get static interferences when listening to either of the more than 100 radio channels. This is because the satellite radio signal can be broadcasted more than 35,000 kilometers or 22,000 miles.The idea of the satellite radio started in 1992. The United States Federal Communications Commission just granted the S band (a spectrum) for the Digital Audio Radio Service. The grant included the license allocated to XM Satellite Radio and Sirius Satellite Radio to broadcast the band in 1997. To date, we have three companies providing satellite radios all across the globe - Sirius, XM and WorldSpace.

Each of these companies offer different broadcasting systems so interested customers will need to buy a different hardware for each. Nevertheless, there are three components common to all the satellite radio services - radio receivers, ground repeaters and the satellites. The different radio signals are broadcasted differently by each radion station. In the case of XM satellite radio, geostationary satellites are used. These satellites have orbits which are synchronized as the Earth moves. The satellites are located just above the equator. XM satellite radio service installed a network of repeaters antennas. These antennas receive radio signals from the satellites which ensure a crystal-clear signal despite obstacles like bridges, hills and buildings. In Sirus' case, they make use of satellites which have elliptical orbits around the globe.

The orbits allow satellites to position themselves higher than the geostationary satellites preventing the loss of signal. - This is also the reason why Sirius has less terrestrial repeaters than XM.

All satellite radio services store a large amount of music - in both CD and digital formats - in their broadcast centers. This is given to life by radio programmers who selects which songs to play at a given time. A number of studios are also managed by radio companies offering live artist performance. The materials are then transmitted to the satellites in digital format ensuring high-quality sound. The satellite encodes tha signal and re-transmits it to the repeaters antennas. After which, it gets transmitted to the radio receiver which decodes and plays the sound. The whole process is actually very quick and very reliable. Satellite radios are made possible by digital compression. It is a process using sophisticated algorithms to compress as much material as possible within the bandwidth. NOte that you will need the appropriate equipment when you subscribe to a satellite radio provider. This is because traditional radios will not be able to decode the signal received from the satellites; this, having the right equipment would be highly necessary.

Satellite radios became popular as an effect of the various technological advancements which inspired its manufacturers to offer the receivers at a good price.

To date, the satellite radio continues to do very well in the market considering its commercial-free feature.