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Satellite radio
1. A satellite radio or subscription radio (SR) is a digital radio signal that is broadcast by a communications satellite, which covers a much wider geographical range than terrestrial radio signals. Satellite radio offers a meaningful alternative to ground-based radio services in some countries, notably the United States. Mobile services, such as Sirius, XM, and Worldspace allow listeners to roam across an entire continent, listening to the same audio programming anywhere they go.
2. Radio services are usually provided by commercial ventures and are subscription-based. The various services are proprietary signals, requiring specialized hardware for decoding and playback. Providers usually carry a variety of news, weather, sports, and music channels, with the music channels generally being commercial-free.
3. In areas with a relatively high population density, it is easier and less expensive to reach the bulk of the population with terrestrial broadcasts. Thus in the UK and some other countries, the contemporary evolution of radio services is focused on Digital Audio Broadcasting (DAB) services or HD Radio, rather than satellite radio.
Определите основную идею текста.
Satellite radio is used alongside terrestrial broadcasts in areas with a relatively high population density.
People avoid employing satellite radio as it is costly and needs specialized hardware for decoding and playback.
Satellite radio is not so popular as Digital Audio Broadcasting (DAB) services or HD Radio in the UK.
Satellite radio is a high quality chargeable radio service available for people on a vast area and requiring specialized mechanical facilities.