Telecom+with+Satellites

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Telecommunication with satellites involves the things you see everyday the tv you watch the calls you make are all by communication satellites. The man who first thought of the communication satellite was British scientist and science fiction writer Aruther C Clarke (1917-). The first U.S communication satellite was Echo launched in 1960. Echo was a plastic balloon covered in aluminium it was 100 ft in diameter i was took en out in 1968. Then the Echo two came and served from 1964 to 1969. AT&T then made the Telestar which was the first active transmitting satellite. It showed tv and transmitted phone calls between Maine, England, and France. At the same time NASA was making a similar satellite called the Relay. Together the Telestar and the Relay where the first multi-satellite system for phone calls and tv. The Telestar satellites are still in use today some from the 90s are still in use.
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 * [[image:http://www.iperceptive.com/images/authorimages/arthur-c-clarke.jpg]]This is Aruther C. Clark ||  || [[image:http://callisto.ggsrv.com/imgsrv/FastFetch/UBER1/00127340]] ||
 * ||  || A communication satellite being launched ||

**Works Cited**

Astronomy & Space: From the Big Bang to the Big Crunch, August 30, 2007
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"Communications satellite." //The Columbia Encyclopedia//, 6th ed. Columbia University Press, 2000. Reproduced in Kids InfoBits. Detroit: Gale, 2012. http://galenet.galegroup.com/servlet/KidsInfo

Aloi, Gianluca, and Pasquale Pace. "Satellite-HAP Network Supporting Multilayered QoS Routing in the Sky." //IETE Journal of Research// 56.3 (2010): 163. //Gale Science In Context//. Web. 15 Mar. 2012.

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The age of communications satellites often has brought about worldwide telephone and television connections, the pictures and videos people see on nightly news and weather reports; electronic international banking; and the transfer of huge amounts of scientific data. One satellite can carry more than one hundred thousand telephone calls and several television signals at one time. Almost any information that relies on cables, lines, or antennas can now be communicated by satellites orbiting about Earth.

A communications satellite, often referred to as comsat, is a spacecraft that orbits Earth and transmits and receives communications data using radio signals. The satellite consists of a relay station equipped with receivers (which receive a signal), amplifiers (which enlarge a signal) and transmitters (which send a signal back). Most of these satellites circle Earth at an altitude of about 22,000 miles (35,400 kilometers) in a geosynchronous orbit, a path that takes twenty-four hours to complete, like one rotation of Earth. If a satellite is launched over the equator, it may attain a geostationary orbit, a special kind of geosynchronous orbit. This situation means that the satellite always travels in the same plane as, and at a fixed position above, Earth's equator and maintains constant contact with relay station on the ground below it. A network of satellites are often used to connect all parts of the globe.

British scientist and science fiction writer Arthur C. Clarke (1917-) first introduced the concept of communications satellites in 1945. He proposed constructing an international communication system using three orbiting satellites. To make this a reality, scientists had to overcome many obstacles. They had to design a machine that could withstand extreme heat and cold and have a power supply that would last years. They also had to figure out how to launch it into orbit

The first U.S. communications satellite, named Echo, was launched in 1960. Developed by American engineer John Robinson Pierce (1919-2002) of Bell Telephone Laboratories, Echo was an aluminum-coated, gas-filled plastic balloon that was 100 feet (30 meters) in diameter. It was placed in a low altitude orbit and functioned until 1968 as the world's first passive reflector communication satellite (meaning that it bounced signals back to Earth, rather than actively transmitting them). The next satellite, Echo II, was in service from 1964 to 1969.

AT&T soon developed Telstar, the first active-transmitting communications satellite. It was launched in 1962, and transmitted telephone calls and television broadcasts between locations in Maine (United States), England, and France. At the same time, the National Aeronautics and Space Administration (NASA) was building a similar satellite called Relay. Together, Telstar and Relay demonstrated the potential of multi- satellite communications systems for telephone and television transmissions. Telstar satellites are still in use--with satellites being launched in 1993 (Telstar 401), 1995 (Telstar 4), 1997, (Telstar 10), 2003 (Telstar 4 to Telstar 8, and Telstar 13), and, most recently, in 2004 (Telstar 18).

Also in 1962, the United States formed the Communications Satellite Corporation (Comsat), to develop a worldwide communications satellite network. Two years later, eleven countries of the international community came together and formed the International Telecommunications Satellite Organization (INTELSAT), to create a jointly owned communications system and to conduct scientific research. Intelsat is now a privately owned company.

Scientists in the former Soviet Union (now Russia and various surrounding countries) were the first to accomplish this feat. In 1957, the Soviets launched the first satellite into orbit, called Sputnik 1, which contained radio transmitters. The first U.S. communications satellite, named Echo, was launched in 1960. Developed by American engineer John Robinson Pierce (1919-2002) of Bell Telephone Laboratories, Echo was an aluminum-coated, gas-filled plastic balloon that was 100 feet (30 meters) in diameter. It was placed in a low altitude orbit and functioned until 1968 as the world's first passive reflector communication satellite (meaning that it bounced signals back to Earth, rather than actively transmitting them). The next satellite, Echo II, was in service from 1964 to 1969. AT&T soon developed Telstar, the first active-transmitting communications satellite. It was launched in 1962, and transmitted telephone calls and television broadcasts between locations in Maine (United States), England, and France. At the same time, the National Aeronautics and Space Administration (NASA) was building a similar satellite called Relay. Together, Telstar and Relay demonstrated the potential of multi- satellite communications systems for telephone and television transmissions. Telstar satellites are still in use--with satellites being launched in 1993 (Telstar 401), 1995 (Telstar 4), 1997, (Telstar 10), 2003 (Telstar 4 to Telstar 8, and Telstar 13), and, most recently, in 2004 (Telstar 18). Also in 1962, the United States formed the Communications Satellite Corporation (Comsat), to develop a worldwide communications satellite network. Two years later, eleven countries of the international community came together and formed the International Telecommunications Satellite Organization (INTELSAT), to create a jointly owned communications system and to conduct scientific research. Intelsat is now a privately owned company. Early satellites did not have geosynchronous orbits. They shifted position relative to Earth and moved in and out of range of the ground stations from which the signals originated. Telstar could communicate with a ground station for only one to four hours per day. That problem was solved in 1963 with the launching of Syncom --a geostationary satellite developed by Hughes Aircraft and NASA. Syncom 's high altitude and twenty-four-hour orbit allowed it to stay in constant contact with stations on the ground. A second Syncom-class satellite was launched in 1964 and several more have been launched since 1984 during space shuttle missions. In 1965, the Soviets put the Molniya into orbit, a geosynchronous satellite that provided television, telephone, and telegraph links all over that huge nation, as well as a platform for scientific observation. In 1971, the Soviet Union, together with other Communist bloc nations, formed an international communications organization called Intersputnik. Other classes of communications satellites include: Marisat, Westar, and Oscar. Marisat satellites provide communication links between ships and stations on shore; Westar satellites, operated by the Western Union Telegraph Company, provide video, data, and voice transmissions throughout the United States, Puerto Rico, and the Virgin Islands; and Oscar satellites are used by amateur radio operators in over sixteen countries. Satcom 1, launched in 1975, helped to develop the early cable television channels such as Home Box Office (HBO) and Turner Broadcasting System (TBS) and to expand the U.S. broadcast television networks such as Columbia Broadcasting System (CBS), ABC (American Broadcasting Company), and National Broadcasting Company (NBC). By the early 2000's, worldwide telephone communication was achieved through the use of networks of small-scale, low-Earth orbiting satellites. Recent improvements in fiber optics (the use of fine, flexible glass rods to reflect light), however, may mean a return to the use of ocean-bottom cables for many types of communications in the future. In the first decade of the twenty-first century, communications satellites are used chiefly for telephony (use of satellites for telephone services), mobile satellite technologies (such as commercial radio systems like Sirius Satellite Radio and XM Satellite Radio), satellite television and radio (two types exist: direct broadcast satellite, such as Direct TV and DISH Network, and fixed service satellite , such as what is used for businesses, universities, and other similar applications), and satellite broadband (wireless Internet connections).

Astronomy & Space: From the Big Bang to the Big Crunch, August 30, 2007

Inmarsat presently represents 86 member countries and has nine satellites in geosynchronous orbits--four of these satellites, the latest //Inmarsat-3// generation, provide overlapping global coverage, and the remainder are available as spares or for leasing to other organizations.

Terminals should be able to work on different frequency bands in order to receive communications on a forward link both from satellites and HAPs. This system consists of three layers: terrestrial layer, HAP layer, and GEO layer.