Yeah, that. Obviously everyone knows that a footprint is the print left by a foot. But, when we’re talking about satellite TV, a footprint is something a bit different.
In satellite terms, the footprint is the area of the planet where a particular satellite signal can be received.
This is the footprint of a DIRECTV satellite that serves several cities in the midwest including Cleveland, Cincinnati, and Detroit (courtesy iamanedgecutter.com.) If you’re inside this yellow shape, you can get those signals. If you’re not, you can’t.
Some satellite beams have a “CONUS” or continental US footprint while others, like the one in the picture, cover only a certain area and are referred to as “spot beams.”
Why is this important? If you’re in an RV or yacht and you travel outside the satellite footprint for the channel you want, you lose that channel. While satellite signals can be fairly precisely aimed, it’s still hard to be super-precise when you’re aiming from 22,000 miles away. Most spot beam footprints extend out about 150 miles from the center give or take, and national “CONUS” beams extend about 100 miles from the shore.