- Satellite TV services and coverage area for mobile antennas
Satellite televisionsignals are broadcast from satellites in the Geostationary orbit22,000 miles above the equator. They beam TV signals towards land where the bulk of subscribers are found, so reception from land is easy to receive and requires an antenna no larger than 18 inches in diameter. However, larger antennas are required for mariners because the TV signals “bleed” out over coastal waters and the signal strength weakens the further offshore a vessel travels. Signal strength also varies from satellite service to service, where services such as DirecTVLatin America broadcast a weaker signal than say, Dish Network.
Satellite TV services change throughout different areas of the continental
United States, but most subscribers usually choose between DirecTVor Dish Networkfor their television programming. In other areas of the world programming can be provided by services such as Bell TVthat brings programming to Canada, or Sky Mexico that provides service to Mexico, Central America, and the Western Caribbean, or DIRECTV Latin America that offers programming to the Eastern Caribbeanand most of South America. Regional services offer coverage in Europeand elsewhere.
Satellite TV services also feature different elements, one in particular being that the
polarizationof their signals differ among some services. For example, the satellite TV services supporting the U.S. and Canada broadcast signals are circularly polarized. As a result, the same antenna configuration is capable of receiving any of these signals, though it will require a receiver for the chosen service. However, SKY Latin Americaand the European services broadcast signals that are linearly polarized. To receive their signals, the same satellite TV antenna is used but a component known as the Low Noise Block (LNB) would have to be changed.
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