Satellite radio service is a new method of receiving audio content, most often when in an automobile. There are currently two providers licensed to broadcast satellite radio within the United States. They are XM Satellite Radio and Sirius Satellite Radio.

The technology works like this: the satellite radio company beams content such as music, talk shows, sports and weather to their satellites, which then beam the content down as a radio signal spread across a wide area. Some areas will not be covered by the satellite signals (tall buildings may block their path, for example) in which case a ground-based repeating station will be required. Many new cars will ship with satellite receivers built in, and there are several aftermarket radios available which will receive the broadcasts.

Unfortunately the two services are not compatible with each other, and if you own a receiver for one it will not work with the other. Sirius claims to have exclusive agreements with Ford, DaimlerChrysler and BMW to provide only Sirius-compatible receivers in their vehicles. XM has an agreement with General Motors, the largest automobile manufacturer in the United States.

Customers will pay $9.95 per month for the service. Both Sirius and XM promise that they will supply many commercial-free music channels in addition to some non-music channels with limited commercial interruption.

It remains to be seen how these companies will survive the internetization of traditional commercial radio stations and the proliferation of MP3 audio. It stands to reason that eventually everyone will have a high speed internet connection in their car, in which case who needs satellite radio?

Outside North and South America, a satellite radio service is provided by Worldspace (see their website at www.worldspace.com).

Worldspace covers Africa, Western Europe, South and East Asia and the northern part of Australia. It uses two satellites in geostationary orbit (Afristar, situated at 21 degrees East) and Asiastar at 105 degrees East). Each satellite has three beams which target specific geographical areas - for example, the Afristar 1 beam covers West Africa and Western Europe. There is only limited overlap between the beams.

The system transmits two sorts of channel: rebroadcasts of international and domestic broadcasters (such as the BBC World Service and Radio France Internationale, and a set of 12 themed music channels. The themed channels are currently free in all areas except East Asia where they are available on subscription. Worldspace have announced that they expect to move to subscription for these services in other areas in the near future. Services from other broadcasters are generally free, with very few exceptions.

The lineup of channels changes from time to time: an up-to-date list is available at www.lyngsat.com/asiastar.html and www.lyngsat.com/afristar.html. Alternatively, try the Worldspace website, although the list there sometimes gets out of date. There are approximately 30-40 channels available in each area.

Reception equipment

There is a range of receivers for Worldspace. In the UK they can be bought for UKP100 (approximately USD140). A typical receiver looks very like a normal radio, with a small (about 5 inch by 4 inch) flat satellite antenna attached. The antenna has an "acceptance angle" of about 80 degrees (ie you can be pointing it up to 40 degrees to either side of the direction of the satellite) so you need not be too precise in setting the thing up. Extension cables and remote antennas are available if required.

Company background

Worldspace was originally funded by an Ethiopian businessman Noah Samara, reputedly with the financial backing of the Saudi royal family (source: Business Week, June 30, 1997). Frequency space was granted to him to operate his service in 1992 on condition that the service included provision to developing countries, and the Worldspace service does continue to provide educational channels on its African beams.

A report on Worldspace's finances by Nathan Vardi for Forbes.com (29 April 2002) says Worldspace has run through nearly US $1 billion. However it has fewer than 3000 subscribers and only 150,000 sets have been sold worldwide, mostly in India and Kenya. The report casts doubt on whether the organisation's business model can be sustained.

Future of Worldspace? Worldspace has plans to launch a third satellite, covering South and Central America, but this has been delayed by disputes over the use of frequency spectrum. Industry analysts also question whether Worldspace can afford the additional capital investment.

The biggest area of expansion for Worldspace at the moment seems to be the Western European market. Several channels have been launched for this area in 2002, including subscription weather information channels.

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