SDARS refers to any satellite-based type of digital radio service. It involves transmitting signals from ground stations to several orbiting satellites, which reflect them back to earth, covering greater lengths than conventional AM and FM radios. Additionally, these satellite radios guarantee clear transmission regardless of your distance from the satellite.
Thanks to their wide coverage, SDARS technology is mostly used in automobiles. However, they can also be incorporated into home stereo systems and office and personal spaces.
What does SDARS stand for?
Satellite Digital Audio Radio Service (SDARS) is the most popular Digital Audio Radio Service (DARS) type in the US. It uses a dual transmission format, whereby signals are transmitted directly through orbiting satellites or terrestrial transmitters.
Satellite transmission reaches excellent lengths, as the signals bounce off the satellite from outer space. However, tall buildings in major cities may interfere with their transmission. To counter this, terrestrial transmitters complement them by ensuring signals reach receivers in shielded regions.
Other factors that assist in SDARS transmission include tracking, control facilities, and telemetry.
Due to dual transmission, SDARS antennas feature LNAs ( Low Noise Amplifiers) and passive components, which receive both weak satellite signals and terrestrial transmitters signals.
For optimal performance, SDARS antenna modules are dual-armed. One antenna is optimized for terrestrial signal transmission, while the other is designed for satellite signal reception.
SDARS Radio History
In 1992, United States radio broadcasting made its first leap into digital technology, which utilizes S-band frequencies.
The S-band, as described by the Institute of Electrical and Electronics Engineers (IEEE), lies in the electromagnetic spectrum, which covers 2GH to 4GH frequencies.
Right after WARC (World Administrative Radio Conference) assigned the 2310 to 2360 MHZ band for global satellite radio services, the Federal Communications Commission (FCC) allocated the 2.3 GHz spectrum of the S-band to the US DARS.
Four companies applied for the specified S-band, but only two got the FCC licenses after paying more than eighty million dollars each in 1997. These include the Sirius satellite radio, formerly CD radio, and XM radio, previously identified as American Mobile Radio.
Sirius and XM satellite radios provide the US with one hundred channels and high MP3-quality digital radio services.
XM satellite radio
XM satellite radio which was the first to launch an SDARS radio station 2001 September 25, is fully owned by XM Holdings.
XM offers seventy-three music channels, thirty-nine talks, entertainment, and news channels, twenty-one weather and traffic streams, and twenty-three sports channels.
Sirius satellite radio
Sirius XM Holdings own Sirius satellite radio. This satellite radio operates in North America and is headquartered in New York City but has smaller stations in Memphis and Los Angeles. Sirius launched its first SDARS radio station in 2002 July 1st.
Sirius provides the US with sixty-nine music channels and sixty-five streams broadcasting news, entertainment, and sports.
SDARS services radio bands
From the WARC global band allocation, the United States satellite radios are allocated a subset of 25MHZ bands running from 2320 to 2345 MHZ. These bands are further divided into subbands for various broadcasts as per the table below.
| Frequency | Service User |
|---|---|
| 2320 - 2324.54 MHz | Sirius Satellite |
| 2324.54 - 2327.96 MHz | Sirius Terrestrial Repeaters |
| 2327.96 - 2332.5 MHz | Sirius Satellite |
| 2332.5 - 2336.225 MHz | XM Satellite |
| 2336.225 - 2341.285 MHz | XM Terrestrial Repeaters |
| 2341.285 - 2345 MHz | XM Satellite |
How does SDARS operate?
All SDARS radio broadcasts use a subscription framework. After purchasing satellite radio receivers, users have to buy subscriptions to activate their devices. An active subscription allows the receiver to decode digital satellite signals.
SDARS subscriptions come in the form of multiple-channel packages where you can go through the options to choose one that best fits your needs.
Depending on your budget, you can get a monthly subscription for $12.95 or more.
Advantages of SDARS
Wide Coverage
Most AM and FM radio station signals can reach a maximum of thirty to forty miles. You’ll have to change stations severally when on long drives across various cities, as the signals keep fading out with distance. SDARS or satellite radio signals can reach more than twenty thousand miles.
Minimum Commercials
Most SDARS radio stations offer commercial-free programs, thanks to the subscription payments which keep them running. This guarantees enjoyable, uninterrupted listening.
Although some broadcasts may have commercials, they are considerably few compared o conventional AM and FM radio stations.
SDARS Future
Satellite radio faced its first stiff competition from the top internet radio services at the start of the new millennium. During this period, online radio began global live streaming, availing their services completely free of charge worldwide. Being a cheaper option, they were able to draw lots of SDARS customers.
SDARS providers tried to push for regulation of their competition with digital radio services but their offer was denied. This left them with no choice but to upgrade their hardware and evaluate their subscription charges to stay relevant.
Although SDARS continues to face competition from free digital radio services, its market is still constantly growing.
For one, satellite radio partnerships with automobiles continue to place them on the map, and their practical size makes them fit for office and personal space.
To Wrap Up
SDARS radios offer the best signal reception and a wide range of stations to cater to all your needs. Although you must buy a subscription to access SDARS programs, it’s absolutely worth it.