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Gals (satellite)
Gals is a series of Russian communication satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...s. The first launch was on 20 January 1994, for Chinese TV broadcast. References External links GALS-1 details and orbit tracking mapGALS-2 details and orbit tracking map Satellite television Communications satellites in geostationary orbit {{communications-satellite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communication Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications satelli ... [...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] |
