Satellite Radio

By G.LAXMANA RAO 11BR1A0436

DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING

Radio……………..?

Radio is the transmission of signals through free space by modulation of  electromagnetic waves.

Satellite Radio………..?

Satellite radio is a subscriber based radio service that broadcast directly from satellites.

Basic Components Of Satellite Radio

The Three Satellite Radio Systems:

• Communication Satellites

• Ground Repeaters

• Radio Receivers

Communication Satellite

• Communication Satellite are man made satellites that orbits earth providing a multitude of communication functions to a wide variety of customers, including military, governmental, private & commercial subscribers.

• Communication satellite is consist of diverse of combinations like : transmitter, receiver, amplifier, regenerator, filter, mux, demux, antenna, waveguide, and about any other electronic communication circuit ever developed.

Ground Repeaters

• Satellite radio reception, poses threats from weather, tall building and mountains that can potentially interfere with broadcasts.

• To avoid the interference caused by tall structures, both Sirius and XM Radio are supplementing their satellite coverage with terrestrial transmitters, called ground repeaters.

Earth Orbits

8

Low Earth OrbitsHeight: 700-2000 km

Rotation Period: 90 min.

Medium Earth OrbitsHeight: 8000-12000 km

Rotation Period: 5-12 hrs.

Geostationary OrbitsHeight:35,780 km

Rotation Period: 24 hrs.

GSONGSO

Orbits

The Satellite Radio Receiver• Existing AM/FM car radio will not be able to receive

satellite radio broadcasts.

• Replacement of the radio with a 3-band capable receiver (AM, FM, Sirius or XM Satellite).

Satellite Radio Receiver

Satellite Radio Companies….

1) XM Satellite Radio2) Sirius Satellite Radio 3) World Space

XM Satellite Radio…..

It start it’s service in limited areas of the United States on September 25, 2001.

It uses two Boeing HS 702 satellites(Rock & Roll)

These satellites launched in GEO.

Sirius Satellite Radio……….It is now operational in the United States, with its official launch on July I, 2002.

It uses 3 SS/L-1300 satellites.

I does not use GEO.

It uses Elliptical orbit.

World Space………...

It is already broadcasting in Africa and Asia, and will begin Broad casting in South America sometime soon.It put two or its three satellites, Afri Star and Asia Star, in GEO.Afri Star and Asia Star were launched in October 1998 and March 2000.

Generation Of DAB Signal…….

Reception Of A DAB Signal………

Advantages …………

Less Interference.Cover’s large distance.It is reliable.It employs a smart receiver.It’s bandwidth is sixty times the bandwidth of a single FM radio station.

It will be an intelligent communications device that will offer more services and conveniences than can be provided by conventional analog technology. It is a bright future for listeners and broadcasters.

Conclusion……….

Any Queries………?????