By Steve Gee
Why do we have satellite television? What’s wrong with the terrestrial broadcasts that we have enjoyed for five decades or more? Well the real benefit lies in the fact that you get more channels. You get more channels because satellite broadcasts are able to utilise more bandwidth than conventional terrestrial systems and can therefore fit more separate channels into the space allowed. Another competitor for your viewing time is cable television of course. Cable has some benefits in being more reliable perhaps but it is also limited by the fact that you must live somewhere where the cable companies are willing to connect you up.
Sattelite television really becomes important in areas where it is not possible to install cable and the broadcast television reception is poor. Both systems use radio wave signals to transmit and the waves travel in straight lines. That means for broadcast television, which is transmitted and received via land-based antenna, that the natural curvature of the earth will eventually break the signals’ line of sight. It also means that other land based signals and obstructions are likely to interfere with the TV signal and cause some distortion.
Using satellites to broadcast the TV signals solves the problem. Orbiting more than 22,000 miles above the ground they revolve around the Earth once every 24hrs, which is the same time as it takes the planet to make one complete rotation. Therefore the satellite will always stay above the same spot on the ground and it is said to be in geostationary orbit. Because the satellite is very high in the sky the transmission of the signal reaches large numbers of customers and people that are in normally remote and inaccessible places are able to take advantage. The satellites not only transmit direct back to the ground, but they are also in communication with each other, making a huge network to distribute to the largest possible numbers of people. Because the satellite is geostationary you only need to set your TV satellite dish once, in the best position to receive a signal. You shouldn’t ever have to move it again.
When satellite television was first introduced the dishes required to receive the signal were very expensive and people were able to set them up to receive programmes that were not really intended for everybody to see. Nowadays people tend to subscribe to a ‘Direct Broadcast Satellite’ (DBS) provider such as DirecTV or Dish Network in the US and Sky in the UK. These providers are able to select programs and broadcast them to people as set packages, for example the ‘Family’, ‘Sports’ or ‘Movie’ packages. Cost will depend on which one you choose to buy.
Satellite TV companies make money from their networks in a variety of ways. There are three methods that are in general use today.
Showing Adverts
Organisations pay the network to broadcast adverts. We all hate it but it does pay for our entertainment, or part of it at least.
Subscriptions
Users pay a monthly fee to receive a channel or group of channels. In actual fact you pay for the means to decrypt the signal that you receive. There is no way to stop anyone from receiving a signal transmitted from a satellite so they encrypt the signal to make it impossible to view without the special equipment and secret codes needed to unscramble the signal.
Licence Fee
If you live in the UK and you possess equipment capable of receiving TV signals then by law you have to pay a licence fee. Note that you don’t have to ever use the equipment to receive and view TV; you just have to possess it. The revenue from the licence fee pays for the British Broadcasting Company or BBC and in return we don’t expect to see advertising or encryption on any BBC channels. This was a good idea in the early days of broadcasting and helped to produce high standards all over the world. My personal opinion however is that now the licence fee serves no purpose other than yet another tax we have to pay and I feel that the BBC should now stand on it’s own two feet. I doubt if that’s going to happen anytime soon though.
Free satellite TV is available when the broadcaster uses only advertising to pay for the content and network.
Five main components are required to make this system work. In order to get the programmes from the producers to the customer they all must be in place and they all must be working correctly. It is in fact surprising that it works at all.
Distribution
Distribution
The DBS provider does not create the programmes themselves, they pay for the right to be able to broadcast them via satellite television. They act as a ‘middleman’ between the ‘programming sources’ or channels and you.
Satellite Television Provider
Signals from the broadcast centre sources are received by the provider and transmitted to the network of satellites in orbit.
Satellites
The satellite network receives the signals, which are then retransmitted back to Earth.
Receiving equipment
Usually a DBS provider will provide you with the equipment to receive the signal. This will include a dish to be fixed to your house by professional installers to receive the signal.
Decoding and viewing
A box close to your TV will take the received signal and decode your chosen channels so that you can watch them.
I bet you never realised that there was so much involved in satellite television. It is indeed a marvel of technology and provides us with high quality up to date entertainment from all over the world. Television technology has come a very long way in such a short time.
About the Author: Steve is an engineer and writes for http://www.sattelite-television.thegrandfatherclock.com
Source: www.isnare.com
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