Direct Broadcast Satellite or DBS came into existence in 1990 with the coming together of four big cable companies. Hughes TV Satellite System for Satellite TV online was born in 1994. Thus tiny digital Satellite dish TV era began. Since then the satellite TV industry along with Satellite dish equipment have seen growth graph rising higher by the days. The legal entanglement has been resolved through brainstorming amount the best in the industry and the viewers are no longer bogged down by legalities they can’t handle.
Satellites are a vital link in modern telecommunications; because microwaves do not reflect from the ionosphere they cannot be used directly for long-range communications, but they can be transmitted up to an orbiting satellite, which then relays them back to a distant part of the Earth. Experiments in satellite communications date from the early days of the space program, in the late 1950s. The earliest successful telecommunication satellite was Telstar, which in July 1962 provided the first transatlantic television link. It orbited the Earth once every 2 ½ hours, but was only useable for about 20 minutes during each orbit, when it was in the right position to be followed by the Earth stations. Then it could transmit 60 telephone calls or one television channel.
Eliminating such gaps in transmission is achieved by launching the satellite into a higher orbit at a height of about 36,000 km around the Equator, so that it encircles the Earth once every 24 hours. Because it exactly follows the rotation of the Earth, it appears to be fixed over a particular place. This is termed as geostationary orbit, and geostationary satellites can be used either as permanent links between two Earth stations or as a means of broadcasting over a wide area. Countries too far from the Equator to use geostationary systems are served by very elliptical orbits in which the satellite is useable for a large proportion of the time for Satellite TV online.
Most international satellite telecommunications are controlled by a consortium of more than 100 countries, called Intelsat. Modern high band width transmission channels of satellite and optical fibres have opened new possibilities of providing higher definition TV pictures through Satellite dish TV. It uses a wider screen for better resolution of details. This bigger sharper picture needs a bandwidth of more than 20MHz, almost four times that required by earlier systems.
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