Satellite Radio from XM Radio, Sirius Satellite Radio, and WorldSpace

Satellite radio is an idea nearly 11 years in the making. In 1992, the U.S. Federal Communications Commission (FCC) allocated a spectrum in the "S" band (2.3 GHz) for nationwide broadcasting of satellite-based Digital Audio Radio Service (DARS). Only four companies applied for a license to broadcast over that band. The FCC gave licenses to two of these companies in 1997. CD Radio (now Sirius Satellite Radio) and American Mobile Radio (now XM Satellite Radio) paid more than $80 million each to use space in the S-band for digital satellite transmission.

At this time, there are three space-based radio broadcasters in various stages of development:

• Sirius Satellite Radio is now operational in the United States, with its official launch on July 1, 2002.
• XM Satellite Radio launched commercial service in limited areas of the United States on September 25, 2001. (They were originally going to launch service September 12, but postponed the event because of the terrorist attacks on the United States.)
• WorldSpace is already broadcasting in Africa and Asia, and will begin broadcasting in South America sometime soon.

Satellite radio companies are comparing the significance of their service to the impact that cable TV had on television 30 years ago. Listeners won't be able to pick up local stations using satellite radio services, but they will have access to hundreds of stations offering a variety of music genres. Each company has a different plan for its broadcasting system, but the systems do share similarities. The key components of all three satellite radio systems are:

1. Satellites
2. Ground repeaters
3. Radio receivers