- Satellite TV solves several problems that plague regular broadcast TV and cable TV. Broadcast TV suffers from a limited range. If you travel far enough from the TV station, the curvature of the Earth eventually starts to interfere with the signal. That creates distortions such as snow and ghosting, and eventually stops the signal altogether. Cable TV solves that problem to a certain extent by running a cable directly into the household. That causes difficulties in rural areas, however, because cable companies do not always service them. The solution becomes a matter of simple geometry, which satellite companies can provide in a way other TV services cannot.
- An orbiting satellite which receives the signal in orbit and then beams it down to a given household does not need to worry about signal distortion. The TV signal goes straight up to the satellite and then straight down again--eliminating the curvature of the Earth from the equation while doing away with the need to run a cable into the house. A satellite dish captures the signal by bouncing it from the dish itself onto a feed horn (the little device pointed at the dish) which then carries it down a cable into the house. To work, the dish needs to be pointed at a particular part of the sky, where the company's satellite hovers in geosynchronous orbit. You may notice that if you wander around your neighborhood that all the dishes on everyone's rooftops are pointed in the same direction. Satellite dishes used to be gigantic to capture the signal properly, but advancing technology has shrunk their size, allowing them to be mounted on any roof or balcony with ease.
- Satellite companies purchase programming from various stations included in their subscription packages, including both local affiliates and national channels like ESPN and HBO. The company receives the signal from each station, and then compresses it before beaming it up to the satellite. The dish then decompresses the signal and divides it into individual channels which you can flip through on your TV. Older satellites used a form of compression called MPEG-2. More recent models have adopted MPEG-4 compression, which allows TV stations to be broadcast in high definition. In addition, most satellite companies encrypt their transmissions to prevent people who have not paid for their services from hacking the signal.
