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Satellite Broadcasting And Satellite Communication
Broadcasting by satellite has enable the subscriber to cable system, Broadcasting has been a very concentrated and closely regulated industry the limited number of broadcasters was traditionally explained by the ‘spectrum constraint’, Satellite can be constrained by the amount of power they can radiate towards the receiving station, which has necessitated the provision of very large earth station antennas at a limited number of sites around the globe. From these ‘gateway’ stations the telecommunication signals are rooted into the terrestrial network. Now, attention has turned to the broadband and interactive potential of satellite services, as well as the convergence with other technologies such as mobile communications, global positioning and the Internet. Satellites are used for a large number of purposes. Common types include military (spy) and civilian Earth observation satellites, communication satellites, navigation satellites, weather satellites, and research satellites. Space stations and human spacecraft in orbit are also satellites. Satellite orbits vary greatly, depending on the purpose of the satellite, and are classified in a number of ways. Well-known (overlapping) classes include low Earth orbit, polar orbit, and geostationary orbit. Satellites are usually semi-independent computer controlled systems. Satellite subsystems attend many tasks, such as power generation, thermal control, telemetry, attitude control and orbit control. Communication through satellites is usually done in the way described bellow:. Television programs origin from a broadcasting studio, it could be a live broadcast or a taped TV program. The program is translated into a signal. The signal is sent up to the satellite with a process called – uplink. When it is received at the satellite, the signal is transmitted to another satellite using a process called turnaround, or it is transmitted back down to earth using a process called downlink. When a signal is down linked back to earth it is received by a satellite dish which we all know. Because of the whole process of up linking and down linking, there is a transmission delay of a few seconds. This is why viewers of a cable channel will see it a few seconds before the viewers of a satellite channel. Article Directory: http://www.articledashboard.com Globcos provides Satellite Distribution, Satellite UP Link, Satellite Downlink, Teleport Services, Flyaway Services, SNG Services, layout Services, Streaming and Satellite Broadcasting to worldwide clientele. |
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