Making of a Satellite Centre

Satellite Systems Division (SSD) of the Space Science and Technology Centre started in 1967 to design and develop satellites. Professor U R Rao was appointed Head SSD in 1969 and this was the beginning of a bigger dream. SSD's initial task was to design and develop a 40 Kg RS-1 satellite as payload for the launch vehicle SLV-3. Starting from less than 10 engineers, it started growing in the years 1970–71 and groups created in each technical field of satellite technology. Professor Sarabhai had sudden death on 30 December, 1971 and Prof MGK Menon took the charge of ISRO as interim Chairman. An opportunity came with the offer of visiting the President of USSR in February 1972 to help in building an Indian satellite and launch by a soviet launch vehicle and the project ISSP was borne. Professor Satish Dhawan took charge as Chairman ISRO in June 1972 and it was decided to move the ISSP to Bangalore, leaving a notional office of SSD at Trivandrum. Six industrial sheds A1–A6 were taken over in semi-finished condition in the under-construction Peenya Industrial Estate of Bangalore.

The ISSP setting up activity started at a very quick pace with the moving of engineers and scientists from SSD as well as from PRL. Simultaneously, ISRO Head Quarters office and Department of Space were being set up at Gymkhana of Indian Institute of Science. Space Application Centre (SAC) was set up at Ahmedabad to develop applications from satellite data as well to develop satellite payloads. SSTC at Trivandrum was renamed as Vikram Sarabhai Space Centre (VSSC) in the honour of the founder, and Prof Brahm Prakash was appointed its director. ISSP was adding new engineers in all disciplines of satellite technology and an electronics laboratory was set up in A5 and A6 sheds. Test facilities like vibration test tables, hot and cold chambers, mechanical workshop and a one-meter thermo-vacuum chamber were set up. Institutions like HAL, CMTI and CIL, and private companies like Hegde and Gole were engaged for quick turn around and for utilising their expertise. Interaction with the Russian team started twice a year, once in Bangalore and once in Moscow. This period of two and a half years was of a very hectic pace of developing and testing of the satellite subsystems and integrating the satellite. The ISSP was launched on 19 April 1975 from the Russian launch complex, and the data was received at ISTRAC ground station at Shri Hari Kota (SHAR). It was renamed as Aryabhata after the launch.

What next? question started coming even before the launch of Aryabhata and it was decided to convert Aryabhata to a Remote Sensing satellite, with minimum changes as remote sensing was seen as a major application of space technology, affecting the life of the people. Satellite for Earth Observation (SEO) was to employ a camera in two bands and a three-channel Microwave Radiometer. SEO-1 was launched on 7 June 1979 and given the name Bhaskara 1. Simultaneously, one of the biggest societal experiments was conducted by ISRO in the project Satellite Instructional Television Experiment (SITE) by beaming specially created education cum entertainment programs through a ATS-F satellite of NASA. Ariane Passenger Pay Load Experiment (APPLE) was undertaken to develop the 3-axis stabilised communication satellite to conduct experiments in satellite communication technology and to create needed infrastructure. APPLE was a technology as well as a schedule challenge.

To provide satellite communication services to the country at the earliest, INSAT-1 (four satellites) was procured from the USA. INSAT-1A launched on 10 April 1982 failed in the first eclipse. INSAT-1B launched a year later brought a satellite communication revolution in the country, spreading TV coverage across the length and breadth of the country, enabling V-SAT communication, meteorology data from VHRR and services like Search and Resque. Launch vehicle SLV-3 started flying in 1979. Though the first few flights were not successful, the second development flight carrying RSD2 brought it to an operational level. Each of these missions had an experimental satellite. The Augmented SLV (ASLV) with added strapons enhanced the capability to 150 Kg and a new satellite bus Stretched Rohini Series (SROSS) was developed. This was used as an opportunity for space science and scientific payloads were added to SROSS missions. Since SLV-3 and ASLV were small to carry state-of-the-art remote sensing payloads, development of PSLV was initiated as a major initiative of ISRO.

Bhaskara-1 and 2 provided invaluable experience in developing the methodology of satellite-based remote sensing, setting up ground systems for data reception, data archival, data processing and data products. However, low resolution of the images could only be used for experimental purposes. It was decided to develop an operational class remote sensing satellite IRS-1. IRS-1A was launched on 17 March 1988 and had multispectral optical payload in four bands and a high-resolution panchromatic camera. It also had large swath vegetation index monitoring payload for global coverage. IRS 1-A put India among leading countries in satellite remote sensing for societal applications and a large number of applications were operationalized. Taking APPLE experience, INSAT-1B was very widely used on an operational basis for satellite communication. INSAT-2 program was taken up as a successor to INSAT-1, to continue and extend the various satellite communication services as well as improve the VHRR payload for meteorological services. INSAT-2A was launched on 10 July 1992 and augmented the services provided by INSAT-1B and 1D. ISRO had entered the operational era of space segment, both, in remote sensing and satellite communication.

Prof U R Rao was the chief architect of ISAC, conceiving it even before Aryabhata was initiated, and he used Aryabhata as an opportunity to move satellite activity to Bangalore, an important milestone towards setting up ISAC. He conceptualized the projects like SEO and APPLE to enhance the relevance and ISSP, increased its visibility and consolidate the technical manpower and infrastructure. This resulted in fulfilling his dream of setting  up of the Satellite Centre on 3rd November, 1976. However, there were many others who contributed to the cause in their own way largely by creating competence in their own area of expertise. Each has played a very important role like a strong link in a long chain. It is the integrated strength and this chapter is an attempt to pay tribute to their contributions.

GPS is a global navigation satellite service provided by the US. Indian weather conditions due to fog and other disruptions make airline services very unpredictable during the winter season. Augmenting satellite navigation signals to enhance its availability, reliability is much more needed in the Indian subcontinent. Hence, a Geo Augmentation System GAGAN was initiated. Noting its large relevance to the public, its utility in the strategic sector and urge to provide secure and reliable satellite navigation service, many countries like Russia, China, Japan and European Union have started their own satellite navigation service. India is uniquely placed and its needs are critical, but regional. Indian Regional Navigation Satellite System (IRNSS) is a unique, low-cost and easy to maintain constellation.