How does car GPS systems work and how accurate are they?
A GPS system relies on satellites orbiting the earth. They require at least three satellite signals to track where you are and where you’re going (hence the phrase “Triangulate your position) GPS systems have come great lengths in the past decade. I have a handheld GPS unit (doesn’t have turn by turn directions) and it almost always has less that 100 ft radius of error. (Satellites can’t be dead accurate) but on average I’d say it’s accurate within 30 feet. As for automotive GPS units, the biggest complaint that I’ve heard was the many of them don’t give correct directions going onto roads that are closed or arent’ even there.
