How Does a Satellite TV Get a Signal?

Geostationary Satellites

TV stations broadcast their audio and video signals into the air from their different studios. The signals go up into the air, where they are received by geostationary satellites. These satellites orbit the earth in what is known as the Clarke Belt, which is about 23,000 miles above the equator.

Transponder Signals

All of these geostationary satellites carry things called transponders, which bounce the TV signals back to earth. There are three main types of transponder signals. There is the ka band frequency, the ku band frequency and the c band frequency. These different bands of signals determine the frequency of the signal as it comes back to earth.

Satellite Dishes

Everyone who has satellite TV has a satellite dish. These satellite dishes receive the ka band, ku band or c band signals and translate them back to something that the TV can read. Usually a satellite dish is anywhere from 18 inches across to 9 feet or more. The satellite dish receives the signal from space and concentrates it on the feedhorn. The feedhorn is the little thing that sticks up out of the satellite dish.

The LNB

The feedhorn collects the signal and sends it to the LNB. The LNB is what changes the signal so that it turns into meaningful information on your TV screen. The LNB amplifies the satellite signal and turns it into something that a TV cable can receive. This cable is called the IFL. The LNB and the IFL send the signal to your TV's satellite receiver, and that is how the signal shows up on the TV screen.

Digital Satellite

Many satellite providers now encode their satellite signals digitally so that more stations can be offered in the same amount of space. The digital encoding makes the signals take up less time and space on the satellites. The data is usually encoded in either the MPEG-2 format or the MPEG-4 format. This is a huge compression of the information that otherwise would take up much more space than it does when digitally compressed.