It is the heaviest Indian satellite launched so far and the 14th in India's ambitious satellite communications programme begun in 1982. The 2,958-kg INSAT-3A, lofted into space on April 10 by the Ariane launch vehicle which rocketed into space from Kourou in French Guyana, climbed to its final parking slot in a geosynchronous orbit last week. "This is a big boost to the country's space-based broadcasting, communication and weather monitoring services," says Indian Space Research Organisation (ISRO) Chairman K. Kasturirangan on this new milestone for India in building communication satellites.

SIGNAL SERVICE Since the early 1980s, nearly Rs 2,500 crore has been spent on developing INSAT satellites. INSAT-3A is the 14th satellite in the series. They were to meet the demands of Doordarshan, the telecom sector and the Meteorology Department. INSAT-3A adds 24 transponders to the existing 96 on Indian satellites. That still won't meet the demand. That's because some satellites malfunctioned and had to be abandoned. Transponders had to be leased from foreign satellites. The growth of TV channels and the telecom sector requires at least 300 transponders by 2005. ISRO says it can provide only 250.

Nearly Rs 2,500 crore has been spent on developing the multi-purpose Indian National Satellite (INSAT) series of satellites since the early 1980s. These satellites are primarily intended to provide communication circuits to the state-owned Doordarshan tv network, meet the demands of the telecommunication sector, mainly the Videsh Sanchar Nigam Ltd (VSNL), and the Indian Meteorology Department. But it has always been a scramble for circuits, with some satellites malfunctioning and being abandoned much before their scheduled lifespan.

Now, for the first time, the INSAT series takes the transponder capacity beyond the 100 mark to 120 with five operational satellites. INSAT-3A has 24 transponders that will add to the 96 available on INSAT-2DT, INSAT-2E, INSAT-3B and INSAT-3C. ISRO has leased an additional short-term capacity from foreign satellites like GE-1A and Thaicom. But that is still far short of the rapidly growing demand for satellite-based communication systems. While the industry demands are expected to rise to over 300 transponders in the next two years, ISRO has projected that it can provide about 250 transponders in four years. The dependence on foreign satellites is, therefore, likely to continue at least until the end of the decade.

India currently receives about 100 TV channels, including 16 24-hour news channels. Many of them are beamed via foreign satellites that have a broadcast footprint over India. However, for the INSAT series of satellites, the first call will continue to be Doordarshan and some private channels. The third generation INSAT-3 satellites are planned to cater to increasing transponder capacity requirements in the INSAT system and for innovative use of satellite capacity for improvement of India's communication infrastructure.

Adding to the profusion of demand for transponder capacity will be Doordarshan's plans to go digital. The opening up of domestic and international long-distance telecommunications to the private players, who are competing with the Bharat Sanchar Nigam Limited and VSNL, and the increasing deployment of VSATs for business communications suggest an increase in satellite usage in the coming years.

To tap this growing demand effectively, ISRO has to devise plans to carry Internet traffic that is currently routed through some of the 15 foreign satellites with a footprint over India as well as foreign destinations. Twenty-four Internet service providers (ISPs) have been permitted to establish 55 international satellite gateways to connect international networks with destinations in India. Another growing worry for ISRO's business is the growth of the terrestrial fibre-optic cable network, which offers bandwidth at much lower costs than satellites and is, therefore, preferred by some ISPs.

Fortunately, satellites offer high-reliability connectivity from any place as long as it falls within their coverage area and despite the growth of the fibre networks there will still remain large tracts of the country that can be accessed better and more reliably by satellite services. But, for the moment, the successful switching on of INSAT-3A and the launch of 3E in less than a year will be the springboard for ISRO to build the more sophisticated INSAT-4 class of satellites. It will also have to meet the emerging challenges keeping in mind the constantly changing shape in platforms and new demands of the communications business including the direct-to-home services. For that is the only way ISRO can stay in the increasingly competitive space communications business