Ever wondered why we have satellite television? I know I have, particularly when we already have terrestrial or broadcast television available. They both seem very similar, the only difference being that with satellite you get lots more choice of channel. Of course there is cable television too, a fierce competitor for both services, but in this article I am going to stick to satellite television.
The local terrain and the curvature of the earth limit terrestrial TV signals in the area that they can server. Both terrestrial and Satellite TV use essentially the same kind of signals but by beaming the signal from above, one satellite is able to serve a wider area. This is why satellite television has become popular in remote areas where it isn't practical to serve people with a land based antenna and certainly not economic to provide cables to those areas.
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.
It is possible to set up a satellite dish on you property and receive signals from a number of different satellites, often for free. To do this you will need a dish that can be moved to point at the satellite you want to receive signals from. Some satellites of interest to amateurs aren't even geostationary so you can only get signals from them for part of the day and your dish needs to be able to track the satellite as it moves across the sky. Most people however want to receive signals for entertainment with the least amount of fuss and so they subscribe to paid 'Direct Broadcast Satellite' (DBS) services like DirecTV, Dish or Sky (UK). The premium channels streamed from these satellite networks are encrypted so you need special equipment to view them and you pay for the encryption key to unlock the decoder.
Satellite TV companies make money from their networks in a variety of ways. There are three methods that are in general use today.
Organisations pay the network to broadcast adverts. We all hate it but it does pay for our entertainment, or part of it at least.
Paying a monthly fee for the right to be able to view channels that are encrypted. Your subscription generally gets you a smart card that is programmed with the decryption information and inserted into your receiver box.
If you are in the UK and you have equipment that is capable of receiving TV signals then the law states you must pay for a TV licence. Note that you don't have to use the equipment; you just have to possess it. The money from the licence fee goes to pay for the British Broadcasting Company or BBC and in return we don't see any advertising or encryption on any BBC channels. This was a good idea in the early days of radio and TV and it helped to produce and maintain high standards of broadcasting all over the world. My personal opinion now however is that the licence fee is nothing more than yet another tax that we have to pay and I feel that the BBC should begin to stand on it's own two feet. I doubt that it will happen anytime soon though.
There are five components needed to link the programme makers and the satellite television customer:
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.
Signals from the broadcast centre sources are received by the provider and transmitted to the network of satellites in orbit.
The signals are received by the satellite network and retransmitted back to Earth.
Equipment normally provided by the DBS to allow you to receive the signal from the satellite above. A receiving dish must be professionally installed somewhere on your property.
A box near your TV will take the signal received and decode your chosen channels into a form that you can watch.
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.
Steve is a software engineer and loves to watch movies on his Satellite Television. He is also the webmaster at Satellite Television Keep in touch with what's new at http://www.sattelite-television.thegrandfatherclock.com