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HS-393
The Hughes 393 (sometimes referred to as the HS-393) is a communications satellite bus introduced in 1985 by Hughes Space and Communications Company. It was a spin-stabilized bus that had twice as much power as the HS-376 platform. Design The satellite bus was designed and manufactured by Hughes. It had a launch mass of , a mass of after reaching geostationary orbit, and an 8-year design life. When stowed for launch, its dimensions were in height and in diameter. With its solar panels fully extended its height was . Its power system generated approximately 2,350 watts of power at beginning of life and 2,200 at end of life, thanks to two cylindrical solar panels. These panels used K7 and K4-3/4 solar cells, with more than twice the number of cells than on the HS-376. The bottom panel was retracted around the body and top panel for launch, and extended downwards for operation. It also had two 38 Ah NiH2 batteries. Its propulsion system was composed of two R-4D liquid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SBS 6 (satellite)
SBS 6 was a geostationary communications satellite designed and manufactured by Hughes (now Boeing) on the HS-393 platform. It was originally ordered by Satellite Business Systems, which later sold it to Hughes Communications and was last used by Intelsat. It had a Ku band payload and operated on the 95°W longitude. Satellite description The spacecraft was designed and manufactured by Hughes on the HS-393 satellite bus. It had a launch mass of , a mass of after reaching geostationary orbit and an 8-year design life. When stowed for launch, its dimensions were long and in diameter. With its solar panels fully extended it spanned . Its power system generated approximately 2,350 Watts of power thanks to two cylindrical solar panels. It also had a two 38 Ah NiH2 batteries. These panels used K7 and K4-3/4 solar cells and were more than twice the number than on the HS-376. Its propulsion system was composed of two R-4D LAE with a thrust of . It also used two axial and four r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JCSAT-1
JCSAT-1 was a geostationary communications satellite designed and manufactured by Hughes (now Boeing) on the HS-393 satellite bus. It was originally ordered by Japan Communications Satellite Company (JCSAT), which later merged into the JSAT Corporation. It had a Ku-band payload and operated on the 150° East longitude until it was replaced by JCSAT-1B. Satellite description The spacecraft was designed and manufactured by Hughes on the HS-393 satellite bus. It had a launch mass of , a mass of after reaching geostationary orbit and an 8-year design life. When stowed for launch, its dimensions were long and in diameter. With its solar panels fully extended it spanned . Its power system generated approximately 2350 watts of power thanks to two cylindrical solar panels. It also had a two 38 Ah NiH2 batteries. It would serve as the main satellite on the 150° East longitude position of the JSAT fleet. Its propulsion system was composed of two R-4D-12 liquid apogee engine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JSAT Corporation
JSAT Corporation (JSAT) was the first private Japanese satellite operator, which owned the JSAT satellites, as well as operated and partially owned the N-Star with NTT DoCoMo. Its origins can be traced to the funding of Japan Communications Satellite Company (JCSAT) and Satellite Japan Corporation in 1985. Both companies merged into Japan Satellite Systems Inc. in 1993. In 2000 the company was renamed as JSAT Corporation and was listed in the First Section of the Tokyo Stock Exchange. On September 1, 2008, the company was merged into the SKY Perfect JSAT Group. History With the opening of the Japanese satellite communications market to private investment, Japan Communications Satellite Company (JCSAT) and Satellite Japan Corporation were founded in 1985. In June of the same year, JCSAT awarded an order to Hughes Space and Communications for two identical satellites, JCSAT-1 and JCSAT-2, based on the spin-stabilized HS-393 satellite bus. JCSAT-1, the first commercial Japane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Business Systems
Satellite Business Systems (SBS) was a company founded by IBM, Aetna, COMSAT (and later wholly purchased by IBM and then subsequently sold to MCI), that provided private professional satellite communications through its SBS fleet of FSS geosynchronous satellites, and was the first company to do so. SBS was founded on December 15, 1975 by the aforementioned companies with the goal of providing a digital satellite communications network for business and other professional clients. History In late 1970, MCI Communications created a subsidiary company named MCI Satellite, Inc. The idea was that satellites could provide 'long distance' service from anywhere to anywhere without having to build thousands of miles of terrestrial network facilities. In early 1971, MCI and Lockheed Missiles and Space Company created a joint venture named MCI Lockheed Satellite Corp. which was the first company to request FCC authorization as a Specialized Common Carrier using satellite based communic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HS-376
The Boeing 376 (sometimes referred to as the BSS-376, and previously as the HS-376) is a communications satellite bus introduced in 1978 by Hughes Space and Communications Company. It was a spin-stabilized bus that the manufacturer claims was the first standardized platform. Design The satellite bus was designed and manufactured by Hughes. This spin-stabilized platform had two main sections. The spinning section was kept rotating at 50 rpm to maintain attitude, and a despun section was used by the payload to maintain radio coverage. The spinning section included the apogee kick motor, most of the attitude control, the power subsystem and the command and telemetry subsystems. The despun section contained the communications payload, including the antennas and transponders. The stock version had a launch mass of , a mass of after reaching geostationary orbit and an 8 to 10-year design life. When stowed for launch, its dimensions were in height and in diameter. With its sol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Satellite Development Center
The Boeing Satellite Development Center is a major business unit of Boeing Defense, Space & Security. It brought together Boeing satellite operations with that of GM Hughes Electronics' Space and Communications division in El Segundo, California. History The facility was originally built by Nash Motors in 1946 and begun production in 1948, building the Nash Rambler. Howard Hughes' Hughes Aircraft Company formed the Aerospace Group within the company when they bought the facility in 1955, when the Nash company became American Motors Corporation and divided the facility into: * Hughes Space and Communications Group * Hughes Space Systems Division In 1953, the Howard Hughes Medical Institute (HHMI) was formed, and Hughes Aircraft reformed as a subsidiary of the foundation. The charity status of the foundation allowed Hughes Aircraft to avoid taxes on its huge income. In 1961, the two Aerospace Group divisions were reformed as Hughes Space and Communications Company. Hughes S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipropellant Rocket
A liquid-propellant rocket or liquid rocket utilizes a rocket engine that uses liquid propellants. Liquids are desirable because they have a reasonably high density and high specific impulse (''I''sp). This allows the volume of the propellant tanks to be relatively low. It is also possible to use lightweight centrifugal turbopumps to pump the rocket propellant from the tanks into the combustion chamber, which means that the propellants can be kept under low pressure. This permits the use of low-mass propellant tanks that do not need to resist the high pressures needed to store significant amounts of gasses, resulting in a low mass ratio for the rocket. An inert gas stored in a tank at a high pressure is sometimes used instead of pumps in simpler small engines to force the propellants into the combustion chamber. These engines may have a higher mass ratio, but are usually more reliable, and are therefore used widely in satellites for orbit maintenance. Liquid rockets can be mono ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commercial Titan III
The Commercial Titan III, also known as CT-3 or CT-III, was an American expendable launch system, developed by Martin Marietta during the late 1980s and flown four times during the early 1990s. It was derived from the Titan 34D, and was originally proposed as a medium-lift expendable launch system for the US Air Force, who selected the Delta II instead. Development was continued as a commercial launch system, and the first rocket flew in 1990. Due to higher costs than contemporary rockets such as the Ariane 4, orders were not forthcoming, and the CT-3 was retired in 1992. The Commercial Titan III differed from the Titan 34D in that it had a stretched second stage, and a larger payload fairing to accommodate dual satellite payloads. All four launches occurred from LC-40 at Cape Canaveral Air Force Station. The first carried two communications satellites, Skynet 4A and JCSAT-2, and was launched at 00:07 UTC on 1 January 1990, which was 19:07 local time on 31 December 1989, maki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ariane 4
The Ariane 4 was a European expendable space launch system, developed by the ''Centre national d'études spatiales'' (CNES), the French space agency, for the European Space Agency (ESA). It was manufactured by ArianeGroup and marketed by Arianespace. Since its first flight on 15 June 1988 until the final flight on 15 February 2003, it attained 113 successful launches out of 116 total launches. In 1982, the Ariane 4 program was approved by ESA. Drawing heavily upon the preceding Ariane 3, it was designed to provide a launcher capable of delivering heavier payloads and at a lower cost per kilogram than the earlier members of the Ariane family. The Ariane 4 was principally an evolution of the existing technologies used, as opposed to being revolutionary in its design ethos; this approach quickly gained the backing of most ESA members, who funded and participated in its development and operation. Capable of being equipped with a wide variety of strap-on boosters, the Ariane 4 gaine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder (satellite Communications)
A communications satellite's transponder is the series of interconnected units that form a communications channel between the receiving and the transmitting antennas. It is mainly used in satellite communication to transfer the received signals. A transponder is typically composed of: * an input band-limiting device (an input band-pass filter), * an input low-noise amplifier (LNA), designed to amplify the signals received from the Earth station (normally very weak, because of the large distances involved), * a frequency translator (normally composed of an oscillator and a frequency mixer) used to convert the frequency of the received signal to the frequency required for the transmitted signal, * an output band-pass filter, * a power amplifier (this can be a traveling-wave tube or a solid-state amplifier). Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Most transponders operate on a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ku Band
The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally german: Kurz-unten), because it is the lower part of the original NATO K band, which was split into three bands (Ku, K, and Ka) because of the presence of the atmospheric water vapor resonance peak at 22.24 GHz, (1.35 cm) which made the center unusable for long range transmission. In radar applications, it ranges from 12 to 18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521–2002. Ku band is primarily used for satellite communications, most notably the downlink used by direct broadcast satellites to broadcast satellite television, and for specific applications such as NASA's Tracking Data Relay Satellite used for International Space Station (ISS) communications and SpaceX Starlink satellites. Ku band satellites are also used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
