n.a navigational system involving satellites and computers that can determine the latitude and longitude of a receiver on Earth by computing the time difference for signals from different satellites to reach the receiver
I don't like the GPS. That's too modern for me. I'm very traditional.
VOA: standard.2010.07.22
It doesn't even need to know what kind of signal it's looking at, and it can get its position in places there's no GPS to work from, whether it's in an urban canyon or the natural kind.