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Eyesat-1
Eyesat-1 is an American experimental communications microsatellite with an store-dump payload. The mission of Eyesat-1 was experimental monitoring of mobile industrial equipment. Eyesat-1 has provided the National Oceanic and Atmospheric Administration in Silver Spring, Maryland, with communication services to the South Pole. Eyesat-1 carries an FM repeater for Amateur Radio Research and Development Corporation (AMRAD) called AMRAD OSCAR 27 or OSCAR 27. Eyesat-1 was launched on September 26, 1993 with an Ariane 4 rocket at Guiana Space Centre, Kourou, French Guiana, along with SPOT-3, Stella, Healthsat-2, KITSAT-2, Itamsat and PoSAT-1. After 19 years of operation, the satellite failed on December 5, 2012. In 2020, the satellite was recovered, and its FM repeater became intermittently operational. Frequencies * Uplink: 145.850 MHz * Downlink In a telecommunications network, a link is a communication channel that connects two or more devices for the purpose of data tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stella (satellite)
Starlette (''Satellite de taille adaptée avec réflecteurs laser pour les études de la terre'', or ) and Stella are nearly identical French geodetic and geophysical satellites. Starlette was launched on 6 February 1975 and Stella on 26 September 1993. Starlette was the first passive laser satellite developed. Background Starlette's development dates back to at least 1972, when scientists at the Centre national d'études spatiales (CNES) were trying to determine a payload for the upcoming first flight of the new Diamant BP4 rocket. After consulting with the Smithsonian Astrophysical Observatory, CNES scientists decided to create a small geodetic satellite optimized for tracking by laser ranging. The project was approved within a few months after a feasibility study by the French atomic agency CEA determined the dense uranium core could be made nearly non-radioactive by using depleted uranium. The Groupe de recherches en géodésie spatiale (GRGS; Space Geodesy Research Grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PoSAT-1
PoSAT-1, the first Portuguese satellite, was launched into orbit on 26 September 1993, on the 59th flight of the Ariane 40 launch vehicle. The launch took place in the Centre Spatial Guyanais, French Guiana. About 20 minutes and 35 seconds after launch, at an altitude of 807 km, PoSAT-1 separated itself from the launch vehicle. The PoSAT-1 weighs about 50 kg and belongs to the class of microsatellites, which are between 10 and 100 kg. The entire project was developed by a consortium of universities and companies in Portugal and was built at the University of Surrey, United Kingdom. The total cost was around €5 million, about €3 million paid by the Portuguese Government and €2 million by the Portuguese companies involved (Po-SAT consortium: Instituto Nacional de Engenharia, Tecnologia e Inovação (INETI), EFACEC, ALCATEL, Marconi Company, OGMA, Instituto Superior Técnico (IST), University of Beira Interior (UBI) and CEDINTEC). The responsible for the project was Fernando ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communications. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;" (either direct monetary or other similar reward) and to differentiate it from commercial broadcasting, public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.). The amateur radio service (''amateur service'' and '' amateur-satellite service'') is established by the International Telecommunication Union (ITU) through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with a unique identifying call sign, which mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency Modulation
Frequency modulation (FM) is the encoding of information in a carrier wave by varying the instantaneous frequency of the wave. The technology is used in telecommunications, radio broadcasting, signal processing, and Run-length limited#FM: .280.2C1.29 RLL, computing. In Analog signal, analog frequency modulation, such as radio broadcasting, of an audio signal representing voice or music, the instantaneous frequency deviation, i.e. the difference between the frequency of the carrier and its center frequency, has a functional relation to the modulating signal amplitude. Digital data can be encoded and transmitted with a type of frequency modulation known as frequency-shift keying (FSK), in which the instantaneous frequency of the carrier is shifted among a set of frequencies. The frequencies may represent digits, such as '0' and '1'. FSK is widely used in computer modems, such as fax modems, telephone caller ID systems, garage door openers, and other low-frequency transmissions. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellites Orbiting Earth
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] |
Downlink
In a telecommunications network, a link is a communication channel that connects two or more devices for the purpose of data transmission. The link may be a dedicated physical link or a virtual circuit that uses one or more physical links or shares a physical link with other telecommunications links. A telecommunications link is generally based on one of several types of information transmission paths such as those provided by communication satellites, terrestrial radio communications infrastructure and computer networks to connect two or more points. The term ''link'' is widely used in computer networking to refer to the communications facilities that connect nodes of a network. Sometimes the communications facilities that provide the communication channel that constitutes a link are also included in the definition of ''link''. Types Point-to-point A point-to-point link is a dedicated link that connects exactly two communication facilities (e.g., two nodes of a network, an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uplink
In a telecommunications network, a link is a communication channel that connects two or more devices for the purpose of data transmission. The link may be a dedicated physical link or a virtual circuit that uses one or more physical links or shares a physical link with other telecommunications links. A telecommunications link is generally based on one of several types of information transmission paths such as those provided by communication satellites, terrestrial radio communications infrastructure and computer networks to connect two or more points. The term ''link'' is widely used in computer networking to refer to the communications facilities that connect nodes of a network. Sometimes the communications facilities that provide the communication channel that constitutes a link are also included in the definition of ''link''. Types Point-to-point A point-to-point link is a dedicated link that connects exactly two communication facilities (e.g., two nodes of a network, an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KITSAT-2
KITSAT-2 ( a.k.a. ''"Uribyol 2", "KITSAT-OSCAR 25", "KO-25" and "KITSAT-B"'') was a South Korean experimental Earth observation microsatellite. KITSAT-2 was South Korea's second satellite and was the first to be developed and manufactured domestically by the Korea Advanced Institute of Science (KAIST). Launch The satellite was launched into orbit on 26 September 1993, at 01:45 UTC, on the 59th flight of the Ariane-40 H10 launch vehicle. The launch took place in the Centre Spatial Guyanais, French Guiana. KITSAT-2 was a South Korean microsatellite that was launched along with SPOT-3. Its mission was very similar to PoSAT-1 (1993-061D). Mission The satellite's mission was to improve and enhance the KITSAT-1 systems, use domestically manufactured components, demonstrate experimental modules and to promote domestic space industry. See also * KITSAT-1 KITSAT-1 or KITSAT-A (Korean Institute of Technology Satellite) is the first satellite to be launched for the South ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Healthsat-2
HealthNet was a satellite communication service that provided healthcare workers in developing nations with access to current medical literature. It also allowed them to exchange information with each other and with colleagues in developed nations. It was operated by American nonprofit SatelLife. Creation The idea of SatelLife began in 1985 as a project to include healthcare organizations from the southern hemisphere in global health discussions. It was proposed by International Physicians for the Prevention of Nuclear War. The organization was founded in 1989, chaired by Bernard Lown. Services The HealthNet constellation provided email services, access to news, electronic conferences, and offline access to websites using a store-and-forward message scheme. The news included selected abstracts and summaries of major medical journals. It also included several newsletters published by HealthNet. Electronic conferences were for discussing medical topics electronically, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPOT-3
SPOT (french: Satellite Pour l’Observation de la Terre, lit. "Satellite for observation of Earth") is a commercial high-resolution optical Earth imaging satellite system operating from space. It is run by Spot Image, based in Toulouse, France. It was initiated by the CNES (''Centre national d'études spatiales'' – the French space agency) in the 1970s and was developed in association with the SSTC (Belgian scientific, technical and cultural services) and the Swedish National Space Board (SNSB). It has been designed to improve the knowledge and management of the Earth by exploring the Earth's resources, detecting and forecasting phenomena involving climatology and oceanography, and monitoring human activities and natural phenomena. The SPOT system includes a series of satellites and ground control resources for satellite control and programming, image production, and distribution. Earlier satellites were launched using the European Space Agency's Ariane 2, 3, and 4 rock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Guiana
French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic Ocean, Atlantic coast of South America in the Guianas. It borders Brazil to the east and south and Suriname to the west. With a land area of , French Guiana is the second-largest Regions of France, region of France (more than one-seventh the size of Metropolitan France) and the largest Special member state territories and the European Union, outermost region within the European Union. It has a very low population density, with only . (Its population is less than that of Metropolitan France.) Half of its 294,436 inhabitants in 2022 lived in the metropolitan area of Cayenne, its Prefectures in France, capital. 98.9% of the land territory of French Guiana is covered by forests, a large part of which is Old-growth forest, primeval Tropical r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
