The remarkable developments in space communication in just three decades since the successful relay of TV signals across the Atlantic in 1962 using TELSTAR, have brought us to the threshold of achieving the capability of establishing human connectivity anywhere in the world, on land, air or sea. The superior quality and reliability of satellite links in combination with their high percentage of availability, distance insensitivity, high degree of flexibility for rapid reconfiguration and their ability to aggregate small requirements to provide cost effective specialised services across vast territories have made satellite communication the most vital link for establishing human connectivity promoting a new perspective of our planet, that of a global village. The evolutionary nature of satellite communication is reflected in their capacity increase, from just 240 voice channels in 1965 to the present day satellites which on an average can easily carry over 20,000 voice circuits, in addition to several TV channels (Pant 1994). Practically all the developing nations in the world today including Asian countries have taken advantage of satellite communication by either leasing transponders from international systems like INTELSAT, INMARSAT and INTER SPUTNIK or by establishing regional systems like Arabsat.
Recognising the paramount need of the Governments, societies and institutions to quickly respond to fast changing situations in a demassified society where niche markets, customised services and rapid transactions are essential to successfully compete in the liberalised global market place, a few Asian countries like India (INSAT), Indonesia (PALAPA), China (CHINASAT), Japan (JCSAT) and Australia (AUSSAT) have already established their own satellite communication systems. Other Asian countries like Korea (KOREASAT), Thailand (THAICOM) and Malaysia (MEASAT) are in the process of establishing their own communication systems to meet their growing requirements of telecommunication and TV distribution services.
Unlike most of the countries, India decided to build its own indigenous technology base and use space technology for solving its national problems on a self reliant basis. Establishing the feasibility of using satellite medium for imparting education in health, hygiene, family planning and better agricultural practices to over 2400 remote rural villages through the year long Satellite Instructional Television Experiment (SITE) conducted using NASA’s ATS satellite during 1975, India successfully launched and operated its own three axis stabilised experimental satellite APPLE in 1981 followed by the introduction of the unique, multipurpose INSAT series of communication satellites to provide operational services on a continuing basis. INSAT system, with over 5000 two way speech circuits covering 140 routes amounting to 150,000 route kms initiated a communication revolution in the country (Fig. 7) connecting for the first time, even remote rural areas and off shore islands with the main stream of the nation using Low Cost Terminals (LCT). The nation wide geographic reach of INSAT satellite has been advantageously used for a variety of applications such as administrative, business and computer communications through a number of captive networks using small terminals. New specialised services such as rural telegraphy to remote areas, news service, facsimile transmission and emergency communication for post disaster relief operations have been commissioned. The National Information Center’s Network (NICNET) using VSATs and spread-spectrum techniques with over 700 micro-terminals provides reliable data communication links interconnecting district headquarters, state capitals, and central government departments. The Remote Area Business and Message Network (RABMN), to provide data communication between city-based industries and construction projects located in remote areas is already operational with over 450 micro terminals and with a registered demand for more than 2000 terminals (Rao 1995b).
Similar expansion of telecommunication to provide low cost VSAT services in addition to point to point communication has been achieved in China, Australia, Indonesia and other countries in Asia either through satellites procured from abroad or through leased transponders. Increasingly all over the world the future trends in communication is towards establishing personalised communication services to meet the needs of the people at individual and group levels. Remarkable developments in digital compression techniques, use of advanced modulation systems for optimal utilisation of space segment and innovative use of low cost VSAT’s to provide several value added services have initiated the new age of information super-highway making it possible to have information on demand. The merging of large computation and communication capabilities through technological innovations are paving the way for the establishment of seamless networks to provide personalised communication and multimedia services including audio, video and data transmission, thus creating a world where communication, information, entertainment and motivation are literally at the will of one’s finger tips. The imminent introduction of mobile communication services in the next three years will surely make the dream of every communication engineer of establishing human connectivity anywhere in the world, on land, air or sea come true.