Sunday, July 15, 2012

VSAT History

The concept of the geostationary orbit was originated by Russian theorist Konstantin Tsiolkovsky, an Imperial Russian and Soviet rocket scientist and pioneer of the astronautic theory. He wrote articles in space travel at the turn of the century. 

In the 1920s, Hermann Oberth and Herman Potocnik, aka Herman Noordung, described an orbit at an altitude of 35,900 kilometers. Its orbital period, or the time for it to make one complete orbit about another object, exactly matched the Earth’s rotational period, making it appear to hover a fixed point on the Earth’s equator. 

Arthur C. Clarke contributed to the understanding of satellites through an article published in Wireless World in October 1945 titled “Extra-Terrestrial Relays: Can Rocket Stations Give Worldwide Radio Coverage?” In this article, Clarke not only determines the orbital characteristics/elements, or the parameters required to uniquely identify a specific orbit, necessary for a geostationary orbit, but also discusses the frequencies and power needed for communications. 

Live satellite communications was developed in the sixties by the National Aeronautics and Space Administration (NASA), named Syncom 1-3. It is transmitted live coverage of the 1964 Olympics in Japan to viewers in the United States and Europe. Soon after, on April 6, 1965, the first commercial satellite was launched into space, Intelsat I, nicknamed Early Bird. 

The first commercial VSATs were C band (6 GHz) receive-only systems by Equatorial Communications using spread spectrum technology. More than 30,000 60 cm antenna systems were sold in the early 1980s. Equatorial later developed a C band (4/6 GHz) two-way system using 1 m x 0.5 m antennas and sold about 10,000 units in 1984-85. 

In 1985, Schlumberger Oilfield Research co-developed the world’s first Ku band (12-14 GHz) VSATs with Hughes Aerospace to provide portable network connectivity for the oil field drilling and exploration units. Ku Band VSATs make up the vast majority of sites in use today for data or telephony applications. The largest VSAT network (more than 12,000 sites) was developed by Spacenet and MCI for the US Postal Service.

See: SDI is No "Star Wars"

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