History
The concept of the geostationary orbit was originated by Russian theorist Konstantin Tsiolkovsky, who wrote articles on space travel around the beginning of the 20th century. In the 1920s, Hermann Oberth and Herman Potocnik, also known as Herman Noordung, described an orbit at an altitude of 35,900 kilometers whose period exactly matched the Earth's rotational period, making it appear to hover over 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 World-wide Radio Coverage?". In this article, Clarke not only determines the orbital characteristics necessary for a geostationary orbit, but also discusses the frequencies and power needed for communications.
Live satellite communication was developed in the sixties by NASA, named Syncom 1-3. It transmitted live coverage of the 1964 Olympics in Japan to viewers in the US 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) 2 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 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 deployed by Spacenet and MCI for the US Postal Service.
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Famous quotes containing the word history:
“A poet’s object is not to tell what actually happened but what could or would happen either probably or inevitably.... For this reason poetry is something more scientific and serious than history, because poetry tends to give general truths while history gives particular facts.”
—Aristotle (384–323 B.C.)
“What you don’t understand is that it is possible to be an atheist, it is possible not to know if God exists or why He should, and yet to believe that man does not live in a state of nature but in history, and that history as we know it now began with Christ, it was founded by Him on the Gospels.”
—Boris Pasternak (1890–1960)
“Jesus Christ belonged to the true race of the prophets. He saw with an open eye the mystery of the soul. Drawn by its severe harmony, ravished with its beauty, he lived in it, and had his being there. Alone in all history he estimated the greatness of man.”
—Ralph Waldo Emerson (1803–1882)