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Fixed-satellite Service
Fixed-satellite service (short: FSS | also: fixed-satellite radiocommunication service) is – according to ''article 1.21'' of the International Telecommunication Union's (ITU) Radio Regulations (RR) – defined as ''A radiocommunication service between earth stations at given positions, when one or more satellites are used; the given position may be a specified fixed point or any fixed point within specified areas; in some cases this service includes satellite-to-satellite links, which may also be operated in the inter-satellite service; the fixed-satellite service may also include feeder links for other space radiocommunication services.'' Classification This ''radiocommunication service'' is classified in accordance with ''ITU Radio Regulations'' (article 1) as follows: Fixed service (article 1.20) * (article 1.21) *Inter-satellite service (article 1.22) *Earth exploration-satellite service (article 1.51) ** Meteorological-satellite service (article 1.52) ; Frequency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Dishes On The Embassy Of Egypt (3595004065)
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which is small CubeSats. Similar satellites can work together as a group, forming constellations. Because of the high launch cost to space, satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Satellites are placed from the surface to orbit by launch vehicles, high enough to avoid orbital decay by the atmosphere. Satellites can then change or maintain the orbit by propulsion, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunication
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded drumb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satcom 1
Satcom, a portmanteau of satellite communications, was a brand of artificial geo-stationary communications satellites originally developed and operated by RCA American Communications ( RCA Americom) that facilitated wide-area telecommunications by receiving radio signals from Earth, amplifying them, and relaying them back down to terrestrial receivers. Satcom was one of the early geostationary satellites; the first were the Syncom series, in 1964. The first Satcom satellite, Satcom 1, was launched on 13 December 1975. The last satellite, Satcom K2, was placed into orbit on 27 November 1985 and was de-orbited in February 2002. Satcom was first superseded and then replaced by the GE series of satellites. The Satcom system passed to General Electric with its purchase of RCA in 1986. RCA Americom became GE American Communications (GE Americom) and the satellite construction division became GE Astro Space. GE Astro Space was sold to Martin Marietta (now Lockheed Martin Spac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Westar 1
Westar 1 was America's first domestic and commercially launched geostationary communications satellite, launched by Western Union (WU) and NASA on April 13, 1974. It was built by Hughes Aircraft, Hughes for Western Union, using the HS-333 platform of spin-stabilisation, spin-stabilized satellites. It operated until 1983. Mission Westar 1 was the first of five Westar satellites launched by Western Union from 1974 to 1982. Westar 1 was launched from Cape Canaveral on a Delta 2914 launch vehicle from Complex 17 on April 13, 1974. The launch vehicle delivered the satellite to a geosynchronous transfer orbit. After transiting to a near geosynchronous apogee, the satellite employed an apogee kick motor to raise the perigee of the orbit and reduce inclination to near-geostationary. Westars 1, 2, and 3 were 12-transponder satellites while Westar 4 and Westar 5 were launched with 24 transponders. Western Union built a Earth station, teleport in Cedar Hill, Texas, to uplink content to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anik 1
The Anik satellites are a series of geostationary communications satellites launched for Telesat Canada for television, voice and data in Canada and other parts of the world, from 1972 through 2013. Some of the later satellites in the series remain operational in orbit, while others have been retired to a graveyard orbit. The naming of the satellite was determined by a national contest, and was won by Julie-Frances Czapla of Saint-Léonard, Québec. In Inuktitut, ''Anik'' means "little brother". Satellites Anik A The Anik A satellites were the world's first national domestic satellites. (Prior to Anik A1's launch, all geosynchronous communications satellites were transcontinental, i.e. Intelsat I and others.) The Anik A fleet of three satellites gave CBC the ability to reach the Canadian North for the first time. Each of the satellites was equipped with 12 C-band transponders, and thus had the capacity for 12 colour television channels. Three channels were allocated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncom 3
Syncom (for "synchronous communication satellite") started as a 1961 NASA program for active geosynchronous communication satellites, all of which were developed and manufactured by the Space and Communications division of Hughes Aircraft Company (now the Boeing Satellite Development Center). Syncom 2, launched in 1963, was the world's first geosynchronous communications satellite. Syncom 3, launched in 1964, was the world's first geostationary satellite. In the 1980s, the series was continued as Syncom IV with some much larger satellites, also manufactured by Hughes. They were leased to the United States military under the Leasat program. Syncom 1, 2 and 3 Common features The three early Syncom satellites were experimental spacecraft built by Hughes Aircraft Company's facility in Culver City, California, by a team led by Harold Rosen, Don Williams, and Thomas Hudspeth. All three satellites were cylindrical in shape, with a diameter of about and a height of about . Pre- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intelsat I
Intelsat I (nicknamed Early Bird for the proverb "The early bird catches the worm") was the first commercial communications satellite to be placed in geosynchronous orbit, on April 6, 1965. It was built by the Space and Communications Group of Hughes Aircraft Company (later Hughes Space and Communications Company, and now Boeing Satellite Systems) for COMSAT, which activated it on June 28, 1965. It was based on the Syncom series of satellites that Hughes had previously built for NASA to demonstrate that communications via synchronous-orbit satellite were feasible. Its booster was a Thrust Augmented Delta (Delta D). After a series of maneuvers, it reached its geosynchronous orbital position over the Atlantic Ocean at 28° West longitude, where it was put into service. It helped provide the first live TV coverage of a spacecraft splashdown, that of Gemini 6 in December 1965. Originally slated to operate for 18 months, Early Bird was in active service for 4 years and 4 months, bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dish Network
DISH Network Corporation (DISH, an acronym for DIgital Sky Highway) is an American television provider and the owner of the direct-broadcast satellite provider Dish, commonly known as Dish Network, and the over-the-top IPTV service, Sling TV. Additionally, Dish offers mobile wireless service, Dish Wireless. On July 1, 2020, Dish acquired prepaid service Boost Mobile and intends to add postpaid service as well in the future. Based out of unincorporated Douglas County, Colorado the company has approximately 16,000 employees. History In January 2008, EchoStar Communications Corporation, which was founded by Charlie Ergen as a satellite television equipment distributor in 1980, changed its name to DISH Network Corporation and spun off its technology arm as a new company named EchoStar Corporation. The company had begun using DISH Network as its consumer brand in 1996, after the launch of its first satellite, EchoStar I, in December 1995. That launch marked the beginning of its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Television Headend
A cable television headend is a master facility for receiving television signals for processing and distribution over a cable television system. A headend facility may be staffed or unstaffed and is typically surrounded by some type of security fencing. The building is typically sturdy and purpose-built to provide security, cooling, and easy access for the electronic equipment used to receive and re-transmit video over the local cable infrastructure. One can also find head ends in power-line communication (PLC) substations and Internet communications networks. Reception Nearly all cable TV systems carry subscription content that is relayed from a satellite in geosynchronous orbit. Encrypted to prevent unauthorized use, this content is uplinked from one or more earth stations operated by various content delivery companies. The content is then analog or digitally modulated and transmitted through the cable network (the OSP or "OutSide Plant") to subscriber homes by means of coa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable TV
Cable television is a system of delivering television programming to consumers via radio frequency (RF) signals transmitted through coaxial cables, or in more recent systems, light pulses through fibre-optic cables. This contrasts with broadcast television (also known as terrestrial television), in which the television signal is transmitted over-the-air by radio waves and received by a television antenna attached to the television; or satellite television, in which the television signal is transmitted over-the-air by radio waves from a communications satellite orbiting the Earth, and received by a satellite dish antenna on the roof. FM radio programming, high-speed Internet, telephone services, and similar non-television services may also be provided through these cables. Analog television was standard in the 20th century, but since the 2000s, cable systems have been upgraded to digital cable operation. A "cable channel" (sometimes known as a "cable network") is a televisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Broadcast Satellite
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter. A satellite receiver then decodes the desired television program for viewing on a television set. Receivers can be external set-top boxes, or a built-in television tuner. Satellite television provides a wide range of channels and services. It is usually the only television available in many remote geographic areas without terrestrial television or cable television service. Modern systems signals are relayed from a communications satellite on the X band (8–12 GHz) or Ku band (12–18 GHz) frequencies requiring only a small dish less than a meter in diameter. The first satellite TV systems were an obsolete type now known as television receive-only. Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Television
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter. A satellite receiver then decodes the desired television program for viewing on a television set. Receivers can be external set-top boxes, or a built-in television tuner. Satellite television provides a wide range of channels and services. It is usually the only television available in many remote geographic areas without terrestrial television or cable television service. Modern systems signals are relayed from a communications satellite on the X band (8–12 GHz) or Ku band (12–18 GHz) frequencies requiring only a small dish less than a meter in diameter. The first satellite TV systems were an obsolete type now known as television receive-only. Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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