SDARS

Digital Audio Radio Service or DARS refers to any type of digital radio service. In the United States it is the official FCC term for digital radio services. The most popular type of DARS in the U.S. is SDARS: Satellite Digital Audio Radio Service, operated by XM Radio and Sirius. XM and Sirius both operate in the 2.3-GHz S band, from 2320 to 2345 MHz.In areas with weak signals, such as downtown areas with tall buildings or parking garages which block satellite signals, Terrestrial repeaters are installed to re-broadcast the signal to ensure continuous coverage.
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