ive and unscramble the digital data signal, which contains up to 100 channels of digital audio. In addition to the encoded sound, the signal contains additional information about the broadcast. The song title, artist and genre of music are all displayed on the radio. In urban areas, where buildings can block out the satellite signal, XM's broadcasting system is supplemented by ground transmitters. (http://www.xmradio.com/newsroom/screen/pr_2001_12_12.htm) Each receiver contains a proprietary chipset. XM began delivering chipsets to its XM radio manufacturing partners in October 2000. The chipset consists of two custom integrated circuits designed by ST Microelectronics. XM has partnered with Pioneer, Alpine, Clarion, Delphi Delco, Sony and Motorola to manufacture XM car radios. Sharp is also working on a home version of the XM radio receiver. Each satellite radio receiver uses a small, car-phone-sized antenna to receive the XM signal. General Motors has invested about $100 million in XM, and Honda has also signed an agreement to use XM radios in its cars. GM began installing XM satellite radio receivers in selected models in early 2001. For $9.99 per month, subscribers can receive the XM signal. For that price, listeners get up to 100 channels of music, talk and news. Many of the channels have no commercials, with none of the channels having more than seven minutes of ads per hour. XM's content providers include USA Today, BBC, CNN/Sports Illustrated and The Weather Channel. The service bolsters that lineup with its own music channels. (Martin R. Davidoff 126-176)Sirius Satellite Radio Unlike XM, Sirius does not use GEO satellites. Instead, its three SS/L-1300 satellites form an inclined elliptical satellite constellation. Sirius says the elliptical path of its satellite constellation ensures that each satellite spends about 16 hours a day over the continental United States, with at least one satellite over the country at a...
