Site: India Space Research Organization (ISRO)
Department of Space Government of India
Antariksh Bhavan, New BEL Road
Bangalore 560-094 India

WTEC: J.N. Pelton (report author)

Host: Dr. K. Narayanan, Director, SATCOM Program


The research, testing and manufacturing facilities of the Indian Space Research Organization (ISRO) are spread over several major centers and units in various parts of India. The headquarters of ISRO is located in Bangalore. The center, which manages the satellite projects and is where ISRO Satellites are assembled and tested, also is located in Bangalore. The center that deals with applications of satellite communications and remote sensing is located in Ahmedabad. The training facilities are located in Ahmedabad and Dehra Dun.


The Indian National Satellite System (INSAT) is a joint venture of the Indian Department of Space (DOS), which is the parent department of ISRO, the Department of Telecommunications (DOT), the India Meteorological Department (IMD), All India Radio (AIR), and Doordarshan (DD). Overall management of the INSAT system is carried out by an INSAT Coordination Committee (ICC). The INSAT program has a history of over two decades that dates back to the experiments carried out by ISRO in India known as the Satellite Instructional Television Experiment (SITE) using the NASA satellite ATS-6.

The INSAT-1 satellites were built by Ford Aerospace Corporation to specifications set by ISRO. These were 1,200 kg class satellites deployed in geosynchronous orbit by Delta launchers. They were launched in the 1980s.

The INSAT-2 series satellites were both designed and built by ISRO itself, with only components being externally supplied. The INSAT system currently in operation consists of INSAT-ID (83 deg. east): INSAT-2E was scheduled for launch in 1998.

The INSAT system provides a comprehensive and integrated range of services. These include domestic long distance communications, meteorological earth observation and data relay, direct broadcast television, national radio networking, television program distribution, standard time and frequency signal dissemination services, satellite news and facsimile dissemination, mobile satellite service, satellite aided search and rescue service, and cyclone warning dissemination service. Not all services are available on all satellites, but these capabilities are all available through the combined system. The search and rescue payload on INSAT complements a LEO satellite system called the International COSPAS-SARSAT system.

The next INSAT series, INSAT-3, is aimed toward achieving continuity of services, increased capacity and improved capability and complete national self-reliance. The first four in the series, INSAT-3A to 3D, will be 2,500 kg satellites and are compatible with the Geostationary Satellite Launch Vehicle (GSLV) being developed by ISRO. The rough estimated cost of this new launch system is put at $40 to $50 million per launch. INSAT-3E is planned to be larger and more capable, with a mass in GEO of about 3,500 kg. A launcher capable of lifting the INSAT-3E to GEO is also under active development.

INSAT-3D will emphasize improved meteorological capabilities, while INSAT-3A to 3C will emphasize enhanced telecommunications capabilities. The 3A to 3D satellites will be deployed between 1999 and 2001. INSAT-3E will move to much higher power and will be capable of delivering 20-24 Ku-band channels at 52 dBW EIRP or 10-12 channels at 55 dBW EIRP and is planned for 2002/3.

Research and development activities to support the INSAT-3 series are focused on shaped beam antennas, linearized solid state amplifiers and higher powered traveling wave tubes, onboard processing, contiguous multiplexing, low noise receivers and improved packaging and harnessing.

In addition to the INSAT-3 development, ISRO is working on a second generation ground system for mobile satellite systems, plus new direct broadcast terminals. There is also a new rural tele-education ground network, known as GRAMSAT, which his being implemented in a phased manner. Finally, there are experiments planned with digital audio broadcasting and high capacity multimedia applications.

The ground systems for the INSAT system are predominantly supplied by Indian industry and in some cases imported from international suppliers.

Private satellite networks using VSAT antennas are now authorized by the Department of Telecommunications. These are being used for distributed databases, image transfer, multimedia broadcasting, CAD/CAM graphic image transfer, and computer networking. Users lease at least one quarter of a transponder for this purpose. The users now include M/S National Stock Exchange, Hughes Escorts Communications Ltd., HCL Comnet, COMSAT-Max, RPG Telecom, WIPRO-BT, Tata Services, ITI, Amadeus Finance, HFCL Satcom, and Punjab Wireless and Communications Networks, and many others are scheduled to start service shortly. Transponders 13 and 14 on all operational INSAT satellites are reserved for this service because of the advantages in terrestrial coordination.

Published: December 1998; WTEC Hyper-Librarian