Why does GPS work when underground and under big buildings but radio signals, Wi-Fi, and cell phone signals struggle?

Question

Why does GPS work when underground and under big buildings but radio signals, Wi-Fi, and cell phone signals struggle?

In: 4773

Answer 1

GPS doesn’t work under ground or in large building especially well. If you are referring to your phones’s location services they use a whole suite of features to provide the appearance of precisely determined location that include GPS/cell tower identification/Wi-Fi Mac identification from data bases such a skyhook /and inertial navigation and even as a last ditch geo ip.

All of these add up to the devices ability to locate itself fairly well, model the world and continue to update location even when one or more of them fail, and fading in or out or report spurious data.