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:
“No event in American history is more misunderstood than the Vietnam War. It was misreported then, and it is misremembered now.”
—Richard M. Nixon (b. 1913)
“To summarize the contentions of this paper then. Firstly, the phrase ‘the meaning of a word’ is a spurious phrase. Secondly and consequently, a re-examination is needed of phrases like the two which I discuss, ‘being a part of the meaning of’ and ‘having the same meaning.’ On these matters, dogmatists require prodding: although history indeed suggests that it may sometimes be better to let sleeping dogmatists lie.”
—J.L. (John Langshaw)
“Let it suffice that in the light of these two facts, namely, that the mind is One, and that nature is its correlative, history is to be read and written.”
—Ralph Waldo Emerson (1803–1882)