How Satellite TV Works – Satellite Technology
Have you ever wondered how satellite TV works? With millions of satellite TV owners who have chosen to get digital satellite TV, there may be some of you who would like to know how the whole process works. I hope the following helps you understand a little better how it all works.
The local terrain and the curvature of the earth limit terrestrial TV signals in the area that they can serve. 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 is not 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 should not ever have to move it again.
If we now send a radio signal to this satellite, we can make the satellite receive, amplify and retransmit this signal back to the earth. Since the satellite is so high, its footprint or viewing area can be very large and thus a large region can receive the signals that it sends down.
Content providers like BBC, ITV, C4, Sky, and other television networks and programming sources, provide their output to uplink centres. These uplink centres beam the data to the satellite. The uplink centres digitize the signals for quality, encrypt the signals for security, and then transmit those signals back up to their orbiting satellites. The satellites receive and rebroadcast the digital signals back down to Earth. So the satellites really act like giant reflectors.
At the users end, the user buys a satellite TV dish antenna, a receiver and other equipment that is required to convert the compressed and encoded signal back into a form that your TV uses. Your satellite dish gathers the signal from the satellites then passes the signal on to your receiver. Your receiver processes the signal to your television and that allows you to get digital satellite TV.
The whole process is what gives you access to hundreds of channels of digital video and audio entertainment at home or at the office.
Satellite TV companies make money from their networks in a variety of ways. There are three methods that are in general use today.
Advertising
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
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.
TV Licence Fee
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 do not 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 do not see any advertising or encryption on any BBC channels.
