Most people know that a signal is relayed from the main distribution center up to the satellite and then bounced back to the dish on your roof in order to deliver TV to your home.

However, not many people actually know how a satellite works and what is involved in creating a network of satellites that can provide coverage to an entire country, or many different countries.

Here, we'll explore a bit of the behind the scenes work that occurs while delivering satellite television to your home.

Up In Space

By definition, a satellite is anything that orbits the Earth in a circular or elliptical path. The Moon is, by this definition, a satellite of the Earth. The Earth, as well, is actually a satellite of the Sun.

As far as modern technology is concerned, a satellite is a piece of equipment that orbits the Earth and performs a certain function.

Satellites are not factory-produced, one size-fits all. Each is specifically designed to perform a certain task, and this makes for a lot of variety. Some satellites form triangulation for GPS purposes, others are used to track weather patters, and some have very specific scientific objectives.

For example, the Hubble Space Telescope is a satellite affixed with an array of lenses and photography equipment that is used to take pictures of space without the atmospheric interference experienced at land-based observatories.

For the purpose of this article however, the satellites in which we are most interested are communication satellites.

Communications Satellites

Inside communications satellites are a number of important systems. For satellite TV customers, it is vital that the satellite stay in a geosynchronous orbit, meaning that it is in the same patch of sky at all times, so the satellite has guidance systems built in to maintain position.

The transponder is, however, the most important component of the equipment. A transponder is a device that receives a signal at one frequency and then retransmits it at another frequency to avoid any interference with the source signal.

Inside each communications satellite are thousands of transponders. The TV provider's transmission center will emit a signal straight to the satellite. The satellite's transponders will analyze that signal and then retransmit it on a different frequency.

The satellite dish mounted on your roof is designed to pick up signals on that frequency and acts like an antenna. The signal then travels to the set-top receiver box, where it is decoded and you can watch your favorite programming.