Digital audio radio service (DARS) is any type of digital radio program 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. and Canada is SDARS (Satellite Digital Audio Radio Service), used by Sirius Satellite Radio and XM Satellite Radio. XM and Sirius both operate in the 2.3-GHz S band, from 2320 to 2345 MHz.[1]
Increasing the spectrum available for more services would be difficult, since unlike C-band and Ku band services, which allow over 200 locations for satellites, S-band satellites must be spaced far apart, with current technology. Existing vehicle antennas would not allow reception of two different stations on the same frequency, though new technology, requiring a new kind of receiver, might be possible.[2]
WorldSpace also operated a DARS network outside the United States and Canada with a footprint covering Europe, Asia, the Middle East and Africa. It used the L-band.[3]
Spectrum resources
In 1992, the World Administrative Radio Conference (WARC) allocated satellite radio services the 2310–2360 MHz band for Broadcasting Satellite Services (audio).[4]
In the United States, from this global allocation, satellite radio (SDARS) services are allocated a subset, the 25MHz from 2320–2345 MHz.[5] This band is further broken down into sub-bands for space-to-ground and terrestrial broadcasts:
Caption text
Lower
Upper Frequency
Usage and original service user
2320 MHz
2324.54 MHz
Satellite (Sirius)
2324.54 MHz
2327.96 MHz
Terrestrial Repeaters (Sirius)
2327.96 MHz
2332.5 MHz
Satellite (Sirius)
2332.5 MHz
2336.225 MHz
Satellite (XM)
2336.225 MHz
2341.285 MHz
Terrestrial Repeaters (XM)
2341.285 MHz
2345 MHz
Satellite (XM)
Digital Satellite Broadcasting Corporation
Digital Satellite Broadcasting Corporation was one of four companies bidding for Satellite Digital Audio Radio Service, or SDARS, licenses in the United States. The service would have been a listener-supported subscription digital audio service.
1995 January: The FCC sets aside 50 MHz (2310 MHz through 2360 MHz) in the S-band for Satellite Digital Audio Radio Service, also known as SDARS and now commonly known as Satellite Radio.[6]
1997 April: American Mobile Satellite Corporation and Satellite CD Radio, Inc. are each awarded SDARS licenses. The companies eventually become known XM Satellite Radio and Sirius Satellite Radio, respectively. Primosphere Limited Partnership and Digital Satellite Broadcasting Corporation are denied licenses by becoming third and fourth lowest bidders, respectively, during the auction.
^Erskine, Daniel H. (2007-05-20). "Satellite Digital Audio Radio Searching for Novel Theories of Action". Rochester, NY. SSRN987358. {{cite journal}}: Cite journal requires |journal= (help)