Advanced Satellite Communication Technology

Dr. S Pal

ISRO Satellite Centre

Bangalore 560 017

INDIA

• The word "Communication" has lost its conventional meaning of sending information from one place to another place on a wired network to a large extent and on wireless network in a limited way. The introduction of space communication and the present era of information technology has changed the current scenario and we have seen the third technological revolution (information + communication = Information Technology) in the last century.

• The present era is called the It era. The technological evolutions which have taken place in the last century, are simply beyond one's imagination.

• Many technological reversals have been seen like the telephone which should have been on the wired network has become wireless while the TV which was wireless, works on cable. Many individual spheres of working have become almost universal, like education has come to the drawing room from school and colleges, sectors like banking, medicines, hospitals etc which were location specific are available on net. There is tremendous convergence and fusion of communications, computers and associated technology in the present era.

• We have heard or read that internet/IP offers opportunities of convergence of date, video and voice on the same network. Most IP related ventures however, were badly hit by the infamous Internet bubble in 2001. one of the most disappointing developments leveraging on convergence of various technologies through IP and the power of vast geographical coverage of satellite in the satellite market in the last 2 years, is clearly the satellite IP multicast and content distribution market.

• There is no shortage of failed ventures and nonstarters. Despite IPs promise of convergence and cost efficiencies, loading video on to core IP infrastructure networks is still taboo because of the BW hugry nature of video transmission. The satellite ISP backbone market, however is suffering. The biggest threat is fibre.

• Internet the new incarnation of mass communication is becoming popular. Internet the parasite which has almost eaten away the host - the telecom channel, is influencing our every sphere of life. Satellites are contributing in a big way in spreading the internet.