Added: 01/13/2006 |
Satellite TVOnce the dishes were huge and expensive, the viewers of satellite TV were few and fanatic. Since then the situation has changed a lot. Nowadays very many houses have obtained that very specific decoration element on the roof ' a dish which isn't anymore that huge and ugly. Or maybe we have simply get used to see them all around. So what is it that something that has slightly become a common thing and a part of everyday life? And how does it work?
Satellite TV is the same wireless as the broadcasting TV, yet it uses satellites for transmitting a radio wave signal bearing information to the houses of the viewers. Satellites are hanging up high in the sky so that the curvy Earth's surface and all the objects on it aren't being obstacles for the signal as they are for the broadcasting stations.
All those TV satellites are staying on the geosynchronous orbit which means that they are turning round the planet in 24 hours. The Earth's making a full turn as we know in the same terms. So a satellite always stays in one point of the sky and viewers don't have to readjust their antennas after they once adjusted them.
To get satellite TV to your house you will have to turn to the service of a direct broadcast satellite provider who will supply you both with all the required equipment and with a package of satellite programs which may vary according to the different subscriber plans.
The hub of the whole system is a broadcasting center. A satellite TV company pays to the companies creating the TV programming (these are both national turnaround channels and local channels) for the right to broadcast that content to their clients by means of satellites.
Powerful dishes and cable nets gather the programming content from the local and national channels then transmit it to the main broadcasting center which creates digital and high-quality stream from all those programs.
Then the signal is compressed. The digital compression is necessary to increase the amount of channels that one satellite can transmit. Most of satellite TV companies use the MPEG-2 format of compression ' the same which is used for DVD.
Then the signal is encrypted to make sure that you'll pay for viewing. After that the huge broadcasting center dishes transmit the signal to the satellite, which spreads it all over the vast area. A dish in you yard receives that signal. The curved surface of the dish reflects all the satellite radio signals so that they focus on the top of a feed horn in the middle of a dish. In the horn the signal is amplified and filtered out of all noises. After that it passes onto a receiver inside of your house.
By means of a proper decoder chip the receiver decrypts the signal, then transforms it from digital and compressed into the analog that already creates a picture on your TV-set.
Also the receiver provides the computers of the broadcasting company with billing information about the pay-per-view channels and supplies you with onscreen programming schedule. Some receivers have digital recorder co that you can record the programs you like on the hard drive. But here's one problem. When you are choosing a channel that you want to watch at the moment from all of the list of satellite channels your receiver picks out that only channel from all the stream so that you can't neither view any other satellite channel on another TV-set connected to the receiver nor record it. This problem can be solved only by purchasing one more receiver.
So that absence of ability to split the channels within the stream yet stays one the general minuses of satellite TV.
The advantages are the perfect quality of a digital signal, a great variety of channels available and the extended areas a of coverage. The last point makes the satellite TV a serious competitor to the cable TV.
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