An Introduction to Satellite Radio Services

Faithful readers will recall the many columns and articles I've written about my attempts to get reliable high-speed Internet access. Most of those stories could be equally applied to the cable TV service that's available to me. For now, satellite services solve both of those problems (Internet and decent television-programming options). I subscribe to DirecDuo and use DirecTV for my TV programming and Hughes DirecPC for Internet connectivity.

Unfortunately, my connectivity woes aren't restricted to the wired world alone. I also live in an area that seems to be a wasteland on the electromagnetic spectrum. No convenient cell towers are nearby, so my cell phone service is almost nonexistent at home, and even radio reception is limited; I can pick up the huge 50,000 watt AM stations in other states, but they don't provide an adequate signal at my house. Reception was so bad this summer that I hooked up a spare computer to the family room home-entertainment system so that I could pay Major League Baseball $9.95 to listen to Phillies' games on the computer and play them back on my outdoor speakers (the same broadcasts that I should be able to get free from my local radio station).

Fortunately, for my music-listening needs, the DirecTV programming includes 31 channels of CD-quality music. For background music, the sound quality is acceptable, and the music selection is fairly good. For news and information radio, I've been using local stations that I can pick up on the Internet, and I often use a small shortwave radio to get programming such as BBC World News.

I must admit that the lack of decent radio affected my life less than the inability to get decent cable or Internet access, which is a major annoyance when your home is your office. But I've been listening to more radio news recently, and the only reliable way I can get access to it at home is through my computers, which isn't really practical when I'm working on cars or mowing the lawn. And regardless of how inexpensive computers get, they are still far more expensive than a radio.

My solution comes from above, in the form of the Digital Audio Radio Service (DARS). DARS is a satellite-based 2.3GHz radio-broadcasting technology that can deliver CD-quality sound to any location that the satellite signal can reach. Two vendors supply satellite radio services in the United States: XM Satellite Radio and Sirius Satellite Radio. International service is available from Worldspace.

Each service owns a satellite network and provides 100 or so programming channels--both commercial and commercial-free. Unlike typical commercial radio, the satellite channels are limited to no more than 7 minutes of commercials per hour. In addition to music channels, both vendors carry programming from traditional media outlets such as ABC, Bloomberg, CNBC, and Fox news.

Although the technology from the two vendors is similar, the two implementations aren't compatible. Receivers are dedicated to either XM or Sirius, and you must decide which vendor offers the programming you desire. The initial equipment releases focus on the automotive marketplace (although Sony has a unit that can move from car to home) and offer users the advantage of never driving out of the range of their favorite satellite radio station.

To provide nationwide coverage in the United States, XM Satellite radio has two satellites in geostationary orbit (which, in an incredible moment of excessive cuteness, they named "Rock" and "Roll"). This means that the satellites stay in the same place relative to the rotation of the earth. XM also has more than a thousand ground-based repeaters, primarily in urban areas where buildings would interfere with the signal reception (obviously not a problem where I live), which is important because XM offers both automotive and portable radio applications. And XM has a third satellite in reserve that it can launch to replace either of the other satellites if necessary. The broadcast data stream includes the music and song information (track, title, and genre) that the radio displays when you play the stream.

Sirius Satellite Radio took a different approach to providing nationwide coverage. The company launched three satellites that orbit in an elliptical path that keeps each satellite over the United States for about 16 hours per day. This overlapping pattern assures that the radio signal is always available to subscribers. As with XM, Sirius keeps a spare satellite on the ground, for "just-in-case" scenarios. Sirius is focusing on the automotive market at this time and doesn't currently offer a home receiver.

The two radio networks are similar in many ways: XM has a large radio-broadcasting facility in New York; Sirius has a similar facility. Both companies beam content to the satellites, which then transmit the content to the radio receivers or repeaters. GM has a large investment in XM (approximately $100 million) and has started installing XM-capable radio receivers (AM/FM/XM) in selected car models. Sirius has agreements with car manufacturers ranging from Ford to BMW to do the same. Looking at the programming descriptions on their respective Web sites, the program names differ, but the content looks similar. Only time will tell whether the US market will support two satellite radio networks. The third player in this market, Worldspace, doesn't offer US service but is already broadcasting in Africa and Asia.