Digital TV - Satellite Datacasting

A satellite has the capacity to extend throughout millions of square miles of terrain and reach all receivers within that region, in a single broadcast. Satellites also excel at point-to-multipoint communications. Therefore datacasting by satellite enables broadcasters to reach the receivers no matter where they are located, and the signal is received simultaneously.

The difference between satellite transmission and land-based communications technologies is the advance in satellite transmission's capacity. Satellite may transmit information simultaneously through point-to-multipoint communication technologies. Whilst Land-based communication's capacity allows a point-to-point based system. Therefore satellite datacasting is increasingly cost effective compared to Land-based communication. A single satellite transmission is simultaneous whereas in Land-based communication a separate connection is required between the broadcaster and each recipient, resulting in higher costs. For example, if you needed to send programming to 5000 sites via telephone line, you would incur 5000 separate switching charges. The downfall in satellite datacasting is the competitive nature of satellite rates. Satellites are extremely beneficial in transmitting to remote areas, like islands or high mountain areas, where land-based alternatives are not possible.<p> Another benefit of satellite transmission in a digital signal is that there is non-degradation as it is transmitted. Therefore the information will be transmitted and received in a complete and free from distortion. This is refereed to as advanced error correction processes, which ensure many fewer transmission errors than occur in traditional communications methods. This high reliability ensures the information broadcasters are transmitting is being received in a timely and complete procedure.<p> Satellite television is a wireless system that delivers television programs directly to a viewer's house. Satellite television is similar to broadcast television in that both transmit programming via a radio signal. It operates by a powerful antenna employed by broadcast stations which transmit radio waves to the surrounding area and received by viewer's smaller antenna.<p>

References

1. Technology for Broadband Satellite Networks (2002) Satellite News. Potomac: Oct 14, 2002.Vol.25, Iss. 39 [on-line] Available at: http://proquest.umi.com.gateway.library.qut.edu.au/pqdweb?index=5&did=000000209456791&SrchMode=1&sid=2&Fmt=3&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1098923066&clientId=14394 Accessed: October 12, 2004.<p> 2. Nice, K., Harris, T. (2004) How Stuff Works - Satellites [on-line] Available at: http://entertainment.howstuffworks.com/satellite-tv.htm Accessed: October 12, 2004. <p>

Amy Harbrow 14:13, 28 Oct 2004 (EST)