| Satellite Digital Audio Radio Service | | | | and out. Now, imagine a radio station that |
| (SDARS):SDAR is a satellite-based | | | | can broadcast its signal from more than |
| direct-broadcast radio service in which | | | | 22,000 miles (35,000 km) away and then come |
| | | | through on your car radio with complete |
| digitally encoded audio entertainment | | | | clarity. One could drive |
| material is broadcast to | | | | |
| | | | nearly hundreds of kilometers without ever |
| Earth-based receivers, either directly from | | | | having to change the radio station! Not |
| an orbiting satellite, or from the satellite | | | | |
| to | | | | only would you never hear static interfering |
| | | | with your favorite tunes, but also the |
| the receiver via a repeater station (This is | | | | |
| a special case in which the receiver is in a | | | | music would be interrupted by few or no |
| | | | commercials.Satellite radio companies are |
| shielded location). SDARS is a radio | | | | comparing |
| communication service through which audio | | | | |
| | | | the significance of their service to the |
| programming is digitally transmitted by one | | | | impact that cable TV had on |
| or more space stations directly to | | | | |
| | | | television 30 years ago. Listeners won't be |
| fixed, mobile, and/or portable stations, and | | | | able to pick up local stations using |
| which may involve complementary | | | | |
| | | | satellite radio services, but they will have |
| repeating terrestrial transmitters, | | | | access to hundreds of stations offering a |
| telemetry, tracking and control facilities. | | | | |
| | | | variety of music genres. Each company has a |
| Through SDARS compact-disc quality audio is | | | | different plan for its broadcasting |
| available because of digital transmition | | | | |
| | | | system, but the systems do share |
| is employed.History of Satellite | | | | similarities.XM Satellite Radio, Sirius |
| Radio:Satellite radio is an idea over a | | | | Satellite |
| decade long. In 1992, the U.S. | | | | |
| | | | Radio and WorldSpace satellite individually |
| Federal Communications Commission (FCC) | | | | provides digital-audio |
| allocated a spectrum in the | | | | |
| | | | radio services (SDARS), with commercial-free |
| "S" band (2.3 GHz) for nationwide | | | | programming, digital-audio quality, and |
| broadcasting of satellite-based | | | | |
| | | | countrywide coverage. Each company offers |
| Digital Audio Radio Service (DARS). Only | | | | nearly 100 channels of digital music and |
| four companies applied for a | | | | |
| | | | talk radio (many of them commercial-free or |
| license to broadcast over that band. The FCC | | | | with a reduced number of commercials) |
| gave licenses | | | | |
| | | | that can be received from coast to coast |
| to two of these companies in 1997. CD Radio | | | | with no service interruption. Each |
| (now Sirius Satellite Radio) and | | | | |
| | | | offering number of music channels, these |
| American Mobile Radio (now XM Satellite | | | | services clearly provides programming options |
| Radio) paid more than $80 million each | | | | |
| | | | not available through traditional radio.One |
| to use space in the S-band for digital | | | | of the main feature of SDARS is SDARS |
| satellite transmission. The first satellite | | | | provides almost Commercial free (or |
| based radio launched by XM on Sep 25, 2001, | | | | Commercials are restricted) programs. And |
| then followed by Sirius on July 1, 2002. At | | | | also it provides news, weather forecasts, and |
| this time, there are three space-based radio | | | | sports apart from |
| broadcasters: | | | | |
| | | | entertainment-based programs The primary |
| Sirius Satellite RadioXM Satellite | | | | application for this service is constant |
| | | | coast-to-coast coverage of radio for cars. We |
| RadioWorldSpace Satellite Radio Importance | | | | have all experienced the problem of trying to |
| and significance of Satellite radio:We all | | | | listen to radio on a long trip. Both AM and |
| have our favorite radio stations that we | | | | FM stations fade in and out as we drive into |
| preset into our car | | | | and out of their coverage |
| | | | |
| radios, flipping between them as we drive to | | | | area. Portable full satellite radio service |
| and from work, on errands | | | | available now a days for |
| | | | |
| and around town. But when you travel too far | | | | the car, home stereo and personal radio |
| away from the source station, the | | | | environments. Car manufacturers have been |
| | | | installing satellite radio receivers in some |
| signal breaks up and fades into static. Most | | | | models for a few years now, and |
| radio signals can only travel about 30 | | | | |
| | | | several models of portable satellite radio |
| or 40 miles from their source. On long trips | | | | receivers are available from a variety of |
| that find you passing through | | | | |
| | | | electronics companies.Signal reception is |
| different cities, you might have to change | | | | generally poor as well as variable in the |
| radio stations every hour or so as the | | | | cases of AM or FM. With the SDARS systems, |
| signals fade in | | | | radio coverage throughout the 48 continental |
| | | | states is solid and continuous. |