Satellite Radio

Satellite radio is – according to article 1.39 of the International Telecommunication Union´s (ITU) ITU Radio Regulations (RR) – a Broadcasting-satellite service.

The satellite's signals are broadcast nationwide, across a much wider geographical area than terrestrial radio stations, and the service is primarily intended for the occupants of motor vehicles. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

Satellite radio technology was inducted into the Space Foundation Space Technology Hall of Fame in 2002. Satellite radio uses the 2.3 GHz S band in North America for nationwide digital audio broadcasting (DAB). In other parts of the world, satellite radio uses the 1.4 GHz L band allocated for DAB.

Satellite radio subscribers purchase a receiver and pay a monthly subscription fee to listen to programming. They can listen through built-in or portable receivers in automobiles; in the home and office with a portable or tabletop receiver equipped to connect the receiver to a stereo system; or on the Internet.

Ground stations transmit signals to the satellites, which are orbiting over 22,000 miles above the surface of the Earth. The satellites send the signals back down to radio receivers in cars and homes. This signal contains scrambled broadcasts, along with meta data about each specific broadcast. The signals are unscrambled by the radio receiver modules, which display the broadcast information. In urban areas, ground repeaters enable signals to be available even if the satellite signal is blocked. The technology allows for nationwide broadcasting, so that, for instance US listeners can hear the same stations anywhere in the country.

Sirius Satellite Radio was founded by Martine Rothblatt, David Margolese and Robert Briskman. In June 1990, Rothblatt's shell company, Satellite CD Radio, Inc., petitioned the Federal Communications Commission (FCC) to assign new frequencies for satellites to broadcast digital sound to homes and cars. The company identified and argued in favor of the use of the S-band frequencies that the FCC subsequently decided to allocate to digital audio broadcasting. The National Association of Broadcasters contended that satellite radio would harm local radio stations.

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Wikipedia