Digital Audio Radio Service
Encyclopedia
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.
and Canada
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 repeater
s are installed to re-broadcast the signal to ensure continuous coverage.
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 too far apart for current technology. Existing vehicle antennas would not allow reception of two different stations on the same frequency, though new technology, requiring different receivers, might be possible.
WorldSpace
also operates a DARS network outside of the United States and Canada with a footprint covering Europe, Asia, the Middle East and Africa using the L-band.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
it is the official FCC
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
term for digital radio services.
The most popular type of DARS in the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
is SDARS: Satellite Digital Audio Radio Service, operated by XM Radio and Sirius
Sirius Satellite Radio
Sirius Satellite Radio is a satellite radio service operating in North America, owned by Sirius XM Radio.Headquartered in New York City, with smaller studios in Los Angeles and Memphis, Sirius was officially launched on July 1, 2002 and currently provides 69 streams of music and 65 streams of...
. XM and Sirius both operate in the 2.3-GHz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
S band
S band
The S band is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. It is part of the microwave band of the electromagnetic spectrum...
, 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 repeater
Repeater
A repeater is an electronic device that receives asignal and retransmits it at a higher level and/or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.-Description:...
s are installed to re-broadcast the signal to ensure continuous coverage.
Increasing the spectrum available for more services would be difficult, since unlike C-band and Ku band
Ku band
The Kμ band is a portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to —in other words, the band directly below the K-band...
services, which allow over 200 locations for satellites, S-band satellites must be spaced too far apart for current technology. Existing vehicle antennas would not allow reception of two different stations on the same frequency, though new technology, requiring different receivers, might be possible.
WorldSpace
WorldSpace
1worldspace, formerly known as 'WorldSpace', is a currently defunct satellite radio network that provided service to over 170,000 subscribers in eastern and southern Africa, the Middle East, and much of Asia with 96% coming from India...
also operates a DARS network outside of the United States and Canada with a footprint covering Europe, Asia, the Middle East and Africa using the L-band.
See also
- Digital AudioDigital audioDigital audio is sound reproduction using pulse-code modulation and digital signals. Digital audio systems include analog-to-digital conversion , digital-to-analog conversion , digital storage, processing and transmission components...
- Digital radioDigital radioDigital radio has several meanings:1. Today the most common meaning is digital radio broadcasting technologies, such as the digital audio broadcasting system, also known as Eureka 147. In these systems, the analog audio signal is digitized into zeros and ones, compressed using formats such as...
- The Digital Audio BroadcastingDigital audio broadcastingDigital Audio Broadcasting is a digital radio technology for broadcasting radio stations, used in several countries, particularly in Europe. As of 2006, approximately 1,000 stations worldwide broadcast in the DAB format....
(DAB) system, a.k.a Eureka - Direct broadcast satelliteDirect broadcast satelliteDirect broadcast satellite is a term used to refer to satellite television broadcasts intended for home reception.A designation broader than DBS would be direct-to-home signals, or DTH. This has initially distinguished the transmissions directly intended for home viewers from cable television...
- SatelliteSatelliteIn the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
- Satellite radioSatellite radioSatellite radio is an analogue or digital radio signal that is relayed through one or more satellites and thus can be received in a much wider geographical area than terrestrial FM radio stations...
- Sirius Satellite RadioSirius Satellite RadioSirius Satellite Radio is a satellite radio service operating in North America, owned by Sirius XM Radio.Headquartered in New York City, with smaller studios in Los Angeles and Memphis, Sirius was officially launched on July 1, 2002 and currently provides 69 streams of music and 65 streams of...
- XM Radio