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Introduction and brief history of satellite communications and satellite
A satellite is any object that orbits another object (known as primary). All citizens who are part of the solar system, including Earth, are satellites either the Sun, or satellites of those objects, like the Moon. Not always easy to decide which is the body of the satellite pair. For all the influence, by way of the primary object is also affected by the satellite. If both are in ufficiently the same mass, they are generally known as a binary system of something based and satellite. General criteria that an object is that the satellite mass center of two things is something in the main. In popular usage, the term usually refers to satellite artificial satellite (a man-made objects orbiting the earth or other bodies). In May 1946, the original World Experimental Design-word circling Spaceship, A satellite vehicle with appropriate instruments can be expected that one of the most potent scientific tools of the twentieth century. The success of satellite Craft will produce a comparable effect of the atomic bomb explosion ... Space age began in 1946, as scientists began using the kidnapped German V-2 rockets to make measurements in the atmosphere above. Before this period, the scientists used balloons that went up to 30 km and radio waves to investigate the ionosphere. From 1946-1952, upper atmosphere research conducted using V-2 and Aerobee rockets. This allows the measurement of air pressure, density, and heat up to 200 km. U.S. has been considering launching orbital satellites since 1945 under the Office of Aeronautics U. S. Navy. Rand Project Air Force report released last over, but do not believe that the weapon was a satellite of military power, instead they appear to be an instrument of science, politics, and propaganda. Following pressure by the American Rocket Society, the National Science Foundation and the International Geophysical Year, the military took an interest in early 1955 and the Air Force and Navy to work Projects Orbiter, which involved using a Jupiter C rocket to launch a small satellite called Explorer 1 on January 31 1958. On July 29, 1955, the White House announced that the U.S. aim to launch a satellite in 1958 and spring. This became known as Project Vanguard. On July 31, states that the Union aims to launch a satellite for the fall of 1957 and on October 4, 1957 Sputnik I was launched into orbit, resulting in Space Race between the two countries. Large artificial satellites now orbiting the Earth International Space Station, which sometimes seem to you ided human eye. Types of satellites · Sky satellite: This is the satellite used for remote observations of planets, galaxies and other space. · Communication satellites: These are artificial satellites stationed in space for the purposes of telecommunications using radio at microwave frequencies. Many of geosynchronous communications satellites orbit using or near geostationary orbit, although some new systems using the World-orbiting satellites. · Earth observation satellites are satellites designed to explore the world, especially from orbit, similar to reconnaissance satellites but the purpose for the use of non-military as environmental monitoring, climate, map making etc. (See especially the celebration of the Earth System.) · Navigation satellites using satellite radio signals when the disease is transmitted by a mobile ground allows recipients to determine their exact location. Relatively clear line of sight between the satellite and ground receiver, by continuing to improve electronic, allows satellite navigation systems to measure the location for the accuracy on the order of a few meters in real time. · Satellite Reconnaissance satellite Earth observation satellite, or sending communications for military use or understanding. Little is known about the full power of this satellite, as the government used to keep their work relevant information with their classified reconnaissance satellites. · Solar power satellites are proposed satellites built in high Earth orbit that uses microwave power transmission to the sun for the world's large antennas that can be used instead of the normal resources. · Space station man-made structure designed for human survival in space. A space center is known from other spacecraft, managed by the lack of major propulsion or equipment landning - but, other vehicles used as transportation to and from the center. Space station is designed for medium-term life in orbit, for a period of weeks, months or even years. · Weather satellites are primarily used satellites to monitor weather and / or climate. · Miniature satellite satellite is a very serious nature and small size. New Classifications are used to categorize these satellites: minisatellite (500-200 kg), microsatellite (below 200 kg), nanosatellite (under 10 kg). Orbit types Often orbit their satellites. Although satellites can be orbited in almost all altitude, the satellite is part of their normal length: · Low Earth orbit (LEO: 200 - 1200km on the face of the earth s) · Middle Earth Orbit (Nico or Vimeo: 1,200-35,286 km) · Geosynchronous orbit (geo: 35,786 km above the earth's surface) and the geostationary orbit (zero inclination geosynchronous orbit). Orbit is a very interesting for satellite communications and will be discussed in detail later. High earth orbit · (what: more than 35,786 km) The following special orbit orbit is also used to categorize satellites: · Molniya orbit: Is the class a very elliptical orbit. A satellite placed in orbit currently using more than the selected regions of the world, is a heresy known as the apogee silent. Molniya orbits are named after a series of Soviet / Russian Molniya communications satellite, which orbits have been used since the mid-year 1960 year class. · Heliosynchronous or sun synchronous orbit: A heliosynchronous orbit, or more general sun-synchronous orbit is an orbit that is always by an object at a particular point of the earth's surface at the same local sun time. This is important for the behavior of satellite imagery on the surface of visible or infrared wavelengths (eg weather, spy and rural Sensing satellite). · Polar orbit: A satellite in polar orbit through or near all the posts on this planet (or other celestial bodies) on each revolution. · Hohmann orbit: The orbit, especially this type, more usually identified as a satellite spacecraft. In Astronautics and aerospace engineering, the Hohmann orbit is the orbital maneuvering spacecraft moving from one orbit to another. · Supersynchronous drift orbit or orbit: the orbit of the geo. Satellites will drift west. · Subsynchronous drift orbit or orbit: orbit near but below the geographically. Used for the satellite to be a change in direction east. Communication satellites A communications satellite (sometimes abbreviated COMSAT) is an artificial satellite stationed in space for communication purposes. Modern communications satellites use geosynchronous orbits, Molniya orbits or Earth orbit Nature. For fixed services, communications satellites provide additional technology Tuners Submarine fiber-optic communications. For mobile applications, such as aircraft communications and satellite-based ship communicationis only feasible means of communication as the use of other technologies, such as cable, is impractical or impossible. Previous missions: The nature of satellite communications can chapwa and articles written by Arthur C. Clarke in 1945. He suggested that the radio relay satellites in Equatorial orbit 24 hours and will remain silent in relation to the earth's surface can be used for long distance radio communications, such as going over come limitations imposed by the curvature of the earth. Sputnik 1, the world's first artificial (non contact) satellite, launched on October 4, 1957. The first satellite relay communications was Project value in 1958, which he used tepe recorder to store and forward messages. It is used to send Christmas greetings to the world of President Eisenhower. Echo NASA satellite launched in 1960. This 100-foot aluminized Mylar balloon to serve as a passive reflector for radio communications. Courier 1b, (built by Philco) also launched in 1960, is the world's first active repeater satellite. Under the description Aliyopewa satellite communcation Milestones in history: -- · Herman POTOČNIK - describes the position in geosynchronous orbit - 1928 · Arthur C. Clarke - proposes a geosynchronous orbit to relay communications and broadcasting - 1945 · Project Score - the first communications satellite - 1958 · Echo I - the first passive reflector satellites - August 1960 · Courier 1b - the first active repeater satellite - October 1960 · Telstar - the first active satellite relays are designed for television transmission and high-speed data communications. Telstar was placed in an elliptical orbit (completed once every 2 hours and 37 minutes), turning in a 45 ° angle at the equator. July 1962 · Syncom - satellite communications in the first geosynchronous orbit. Syncom 2 revolved around the earth once a day at a constant speed, but because they still have a north-south special equipment needed to track it. 1963 · Oscar-III - Amateur radio's first communications satellite - March 1965 · Molniya - the first Soviet satellite communications, highly elliptical orbit - October 1965 · Early Bird - The first INTELSAT satellite for commercial services - April 1965 · Orbita - the first national television network based satellite television - November 1967 · Anik 1 - The first satellite of the national television system, Canada, - 1973 · Estar 1, the USA's first geosynchronous communications satellite - April 1974 · Ekran - the first series Direct-To-Home satellite television communications in 1976 · Lapa A1 - Indonesia's first communication satellite - July 8, 1976 · TDRSS - The first satellite designed to provide communications relay services for other aircraft. - 1983 · Mars Global Surveyor - the first communications satellite in orbit around another planet (Mars) - 1997 · World Cassini Spacecraft RELAYS images from Huygens probe on Saturn's moon as the earth, titanium, the long relay to date. - January 14, 2005 Depending on the needs of satellite communications can be placed in different orbits. We discuss some common types: -- (a) the geostationary orbit Satellites: A satellite in geostationary orbit will likely remain in place-based Earth Observer. A geostationary satellite revolves around the earth at a constant speed once a day over the equator. Geostationary orbit is important for land-based communications applications because of the antenna, which should be directed toward the satellite, they can work efficiently without the need for expensive equipment to monitor the movement of satellites. Especially for applications that require large amounts of ground antennas (as one of TV distribution), the savings in ground equipment can more than justify the additional cost and complexity of onboard delete a satellite in geostationary orbit relative. The concept of geostationary communications satellite was first proposed by Arthur C. Clarke, building on work by Konstantin Tsiolkovsky and the 1929 work by Herman Potočnik (writing as Herman Noordung) Das Problem der Befahrung des Weltraums - der Raketen-motor. October 1945 Clarke published an article titled Extra-Terrestrial RELAYS in British magazine Wireless World. This article describes the fundamentals behind stationed in geostationary orbits of artificial satellites to deliver radio signals objectives. Arthur C. Clarke was so often quoted that he was the inventor of satellite communications. The first geostationary communication satellite is Anik 1, Canadian satellite launched in 1972. The United Nations launched a geostationary communications satellite itself later, Western Union 1 satellite launch their estar in 1974, and RCA Americom (later GE Americom, now SES Americom) Satcom 1 launch in 1975. Satcom 1 was that he was instrumental in helping early cable TV channels such as TBS (now TBS Superstation), HBO, CBN (now ABC Family), and The Weather Channel to be successful, because these channels distributed their programming all the local cable TV headends using satellite. Also, first used for satellite TV network broadcast in the United States as ABC, NBC and CBS, to distribute their programs all the stations of their local Affiliate. Reason Satcom 1 was so widely used is that the communication had twice the capacity estar 1 (24 transponders of estar 1 s 12), which produces reducing the use of transponder costs. In 2000 Hughes Space and Communications (now Boeing Satellite Systems) was built nearly 40 percent of satellite services around the world. Other major producers include satellite Space Systems / chloral, Lockheed Martin (former owner of RCA Astro Electronics / GE Astro Space business), Northrop Grumman, Alcatel Space and EADS Astrium. (b) Low-Earth-orbit satellites: A Nature generally was round Earth's orbit around the orbit 150 miles above the earth's surface and, thus, the time (the time around the earth) of about 90 minutes. Because of the nature of the long, these satellites can be seen from the inside radius of 1000 kilometers from the point of small satellites. In addition, the original earth orbit satellites to change their positions relative positions rapidly. Thus, even for local applications, the number of satellites needed if the mission requires uninterrupted connectivity. Satellite low earth orbiting cheaper for the position in space than geostationary satellites and, because of their close distance matters less, require less signal strength. So there is a trade-off between the number of satellites and costs. In addition, there are important differences in the ground and onboard equipment they need to support the two missions. Satellite groups working in concert satellites known as Constellation. Two constellations are aimed at human hands telephony providers, particularly in rural areas, the Iridium and Globalstar. The Iridium system has 66 satellites. Another LEO satellite Constellation, with support from Microsoft entrepreneur Paul Allen, is that as many as 720 satellites. It is also possible to use the World vaccinations cut natural satellite orbit capacity to store data received as it passes through one of the world and then when the transmission is through the other. This will be the case and Canada Disambiguationspage CASSIOPE system of satellite communications. (c) Molniya satellites: As mentioned, geostationary satellites are forced to drive on the equator. As a result, they are not always suitable for service at high latitudes: for at high latitudes a geostationary satellite may appear in nature (or even less) eye, and the influence and causing access multipathing (interference caused and shows the signal from ground to ground antenna) . The first satellite Molniya series was launched on April 23, 1965 and used for experimental transmission of TV signals from Moscow to station downlink uplink stations, located in the Russian Far East, in Khabarovsk, Magadan and Vladivostok. In November 1967 Soviet engineers created a unique system of national TV network of satellite television, called Orbita, which is based Molniya satellites. Molniya orbits can be attractive alternative in such cases. Molniya orbit is tilted, guaranteeing good elevation over selected positions in the northern part of the orbit. (Elevation is the extent to which the satellite's position on the horizon. That the satellite on the horizon has zero elevation satellite directly overhead has elevation 90 degrees). Molniya orbit is so designed that the satellite spends most of his time at latitudes far north, where his ground footprint moves only slightly. Period is half a day, so the satellite will be available for operation over the targeted region for eight hours every second revolution. In this way the third Constellation Molniya satellite (plus in-orbit spares) can provide coverage disrupted. Molniya satellites are typically used for telephony and television services over Russia. Another application is to use radio and telephone systems (even at low latitudes) since the vehicle went through the urban areas need access to the satellite at high altitude to get a good connection, the example in front of tall buildings. Satellite Applications (a) phone: One of the increased use of satellite communications in providing long distance telephone service. Connectivity is via the frequency division multiple access (FDMA) or time division multiple access (TDMA) dependent. Phone subscribers can be connected through the exchange networks connected to the satellite earth station that the traffic to the satellite uplink for more than processing. (b) Television and Radio: There are two types of satellites used for television and radio: (i) Direct Broadcast Satellite (DBS): A direct broadcast satellite is a communications satellite that transmits a small DBS satellite dishes (typically a diameter of 18-24). Direct broadcast satellites generally work on the part of the Ku band. Technology-oriented DBS used for DTH (Direct-To-Home) satellite TV service, like DirecTV and Dish Network in the United States, Canada's ExpressVu, and Sky Digital in the UK. (ii) Fixed Satellite Services (FSS): Use of C band and Ku band bottom. They are usually used for broadcast feeds to and from television networks and local stations Affiliate (as program feeds for network and syndicated programming, live shots, and backhauls), as used for distance learning schools & universities, business television (BTV ), videoconferencing;, and total business communications. FSS satellites are also used to distribute national cable channels and cable TV headends. FSS satellite DBS satellite linatofautiana has RF output power less than a second, which requires a very large plate received (3-8 meters in diameter for Ku band and 12 meters for the C band). FSS satellite technology was also previously used for DTH satellite TV from late 1970 and early 1990-the year in the United States in the form of TVRO (Television Receive Only) receiver and dish (aka big-plate, or better known as pejoratively big ugly dish, system). It is also used in his band, Ku-form of the now defunct Primestar satellite TV service. (c) Mobile satellite technology: Initially available for broadcast TV antenna stationary, in 2004 popular mobile broadcast applications directly to their appearance and that the arrival of two satellite radio systems in the United Nations: Sirius and XM Satellite Radio Holdings. Some industries also introduced a special antenna to receive DBS television telephone. Using GPS technology as a reference, this antenna automatically to return the satellite no matter where or how the vehicle (mounted on the antenna) is a country. Popular satellite antenna with several owners of recreational vehicles. If the phone DBS antenna is also used by JetBlue Airways for DirecTV (and provided the Group, a subsidiary of JetBlue), which passengers can view on-board LCD screen mounted on the chair. (d) Amateur Radio: Amateur radio operators get the Oscar satellites that have been specially designed to carry amateur radio traffic. Working as many satellites as repeaters, dirty places, and generally accessible to the amateur UHF or VHF radio equipment and directional antennas as Yagis or dish antennas. Because of limited land-based equipment Amateur, many Amateur Satellites are launched into orbit a gentleman of Nature Earth, and is only designed to handle a small amount of communication on every brief. Some satellites also provide further data using X.25 or similar protocol. Satellite Broadband Services: In recent years, satellite communications technology is used as a way to connect to the Internet through a broadband data connection. This can help to test users who are located in areas far away, and can not access to wireline broadband or Dialup connection. Countries to launch satellites This list includes districts with an independent set of satellite orbit, including the launch vehicle production key. Many countries have launched satellites built with help from others. French and English now included by the power of the European Union under the European Space Agency. Launch of the first countries In the first country to launch first satellite Russia's 1957 Sputnik 1 United States1958 Explorer 1 Asterix France 1965 Japan 1970 Osumi China 1970 Dong Fang Hong I United Kingdom1971 Prospero X-3 Union1979 European Ariane 1 India Rohini 1980 Israel 1988 MoFEA 1 Iranian 2005 Sina 1 In 1998, North Korea admitted to launching a satellite, but this was never confirmed, and it is believed that the insurance for the test launch of a Taepodong-1 missile over Japan (See Kwangmyongsong). Link to this article: Related publications Pc satellite TV programs - why you should consider switching the TV system? Year: 12-01-2011 | author: Ralph Taub Satellite tv offers many channels and is hd ready Year: 19-04-2008 | author: Mary Phillips Tbs is very funny on satellite tv Year: 26-11-2008 | author: John R. 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