DIGITAL SATELLITE

RADIO Prof.Minakshi Atre

PVG

SDARS XM RADIO Satellite digital audio radio service

(SDARS) is a satellite-based direct-broadcast radio service

In SDARS, digitally encoded audio entertainment material, is broadcast to earth-based receivers either directly from an orbiting satellite, or in cases in which the receiver is in a shielded location from the satellite, to the receiver via a repeater station.

SPECIFICATIONS OF SDARS TUNER 1. Frequencies and Channel Bandwidth: XM is assigned 12.5MHz of spectrum

range from 2332.5 to 2345MHz centered on 2338.75MHz. (i.e channel BW is 12.5 MHz)

This spectrum is roughly divided into sixths

Four bands are assigned to the transmitting satellite and two are assigned to a terrestrial repeater network.

WHAT ARE REPEATERS

In satellite wireless, a repeater (more frequently called a transponder) receives uplink signals and retransmits them, often on different frequencies, to destination locations.

SDARS FREQUENCY BANDS

WHAT IS WCS WCS: wireless communication service The Wireless Communications Service

(WCS) is in the 2305-2320 and 2345-2360 MHz spectrum range.

The most common use of WCS spectrum is :

mobile voice and data services, including cell phone, text messaging, and Internet.

2.Modulation: Satellites use QPSK modulation and Repeaters use COFDM modulation to

realize the requirements of terrestrial broadcasting.

BEGINNING OF NEW ERA OF DIGITAL RADIO For decades, to listen to radio

entertainment, you had two choices: AM radio and FM radio.

But in the last few years, an entirely new way to listen to radio has emerged.

Satellite radio is now available, in a digital audio format, for subscription through two services in the US - XM Radio and Sirius Satellite Radio.

Programming is provided by satellite, not from local radio broadcasting towers.

This means that these services can reach the entire country, accessing a tremendous audience.

So rather than listening to music or news on your local radio station, you are receiving national broadcasting - similar to what you have been experiencing with home entertainment television for decades.

And many of the music entertainment channels on satellite radio are actually live radio - not everything is pre-recorded.

XM RADIO HAS TWO SATELLITES (NAMED XM 'ROCK' AND XM 'ROLL') AND SIRIUS HAS THREE.

These satellites are stationed above the US, beaming the radio signal almost everywhere in the country.

And there are multiple terrestrial repeaters that enhance the signal and provide service where the satellite signal could be blocked by natural or man-made features.

This way whenever you want to listen to a song or a traffic report, it will be available on your satellite radio.

The signals provided by these services are high quality, digital audio format.

Therefore, the sound you can receive will be far superior to broadcast radio, depending on your receiver equipment.

SATELLITE RADIO IN THE US BEGAN ON JANUARY 5, 2001.TIM MCGRAW WAS THE FIRST ARTIST EVER PLAYED ON SATELLITE RADIO. HE GAVE A SPECIAL WELCOME INTRODUCTION WHICH SEGUED INTO HIS SONG "THINGS CHANGE" ON SIRIUS!

XM Satellite Radio and Sirius Satellite Radio each launched such a service at the beginning of the 21st century. 

Satellite radio, also called digital radio, offers uninterrupted, near CD-quality music beamed to your radio from space.

They decided to merge in 2007 and FCC allowed the merger to go forward in 2008

IN THE UK AND OTHER COUNTRIES, THE CONTEMPORARY EVOLUTION OF RADIO SERVICES IS FOCUSED ON DIGITAL AUDIO BROADCASTING (DAB) SERVICES OR HD RADIO, RATHER THAN SATELLITE RADIO. SATELLITE RADIO, PARTICULARLY IN THE UNITED STATES, HAS BECOME A MAJOR PROVIDER OF BACKGROUND MUSIC TO BUSINESSES SUCH AS HOTELS, RETAIL CHAINS, AND RESTAURANTS.

THANK YOU