The Indian National Satellite Systems (INSAT)

The Indian National Satellite Systems (INSAT) in one of the largest domestic communication satellite systems in the Asia- Pacific region. In the 1980's, it initiated a major revolution in India's communications sector and sustained the same later.

The satellites of INSAT system, which are in service today, are INSAT-2E, INSAT-3A, INSAT- 3B, INSAT-3C, INSAT-3E, and KALPANA-1, GSAT- 2, and EDUSAT INSAT-4A. The system provides a total of about 175 transponders in the C, Extended C and Ku-bands. Being a multipurpose satellite system, INSAT provides services to telecommunications, television broadcasting, weather forecasting, disaster warning and search and Rescue fields.

The INSAT system serves many important sectors of the Indian economy. INSAT is providing Mobile satellite service besides providing VSAT service. Today, more than 25,000 very small aperture Terminals are in operations.

Television broadcasting and redistribution are also have been benefited by INSAT. Social development through exclusive channels for training and developmental education has become possible through INSAT.

Telemedicine network in taking medical services to the remote and rural population. The launch of EDUSAT, the India's flat thematic satellite dedicated exclusively for educational services, has provided further fillip to the educational services offered by the INSAT.

INSAT system is also providing meteorological services through Very High Resolution Radiometer and CCD cameras on some of its spacecraft. This apart, cyclone monitoring through meteorological imaging and issue of warnings on impending cyclones through disaster warning receivers have been opertionalised. '

The INSAT system uniquely provides geostationary platform for simultaneous domestic communications and earth observation functions. The first four generation INSAT series (INSAT- 1A, -IB, -1C and ID) were all US-built and launched by either US or European space launch vehicles. The INSAT-class satellites are joint ventures of India's Department of Space (DOS), Department of Telecommunications (DET), India Meteorological Department (IMD), All India Radio and Doordarshan. Overall co-ordinateion and management rests with the inter-ministerial INSAT Coordination Committee (ISS).

The satellites are handled from the INSAT Master Control Facility (MCF) at Hassan in Karnataka.

With the aid of the first generation INSAT series, telecommunications expanded comiderably by providing inter-city networks and trunk routes. The meteorological service was integrated into the INSAT series. So it is a novel three-in-one concept that provides satellite television broadcasting communication and meteorological services from a single platform.

By the end of the first generation INSAT systems, ISRO had developed its own capability to build the second generation. The second generation has improved capabilities in newer frequencies and an improved radio meter for weather observation.