GPS home

This website is about accurate GPS positioning systems. I'm in the process of building it and it will get bigger.

Strictly, the correct term is GNSS systems, GPS now being one of many.

A Global Navigation Satellite System (GNSS) device is a radio receiver that uses signals from orbiting satellites to find its position on the surface of the Earth. There are now four neworks ("constellations") `of GNSS satellites ecah providing coverage across the whole planet: the American Global Positioning System (GPS), the European Galileo system, the Russian Glonass system and the Chinese Beidou system. There are other constellations providing local coverage. Receivers are available that can use any or all of these satellites to find their position pretty much anywhere outside with an open view of the sky.

Receivers have been available since the late 1990s that can find their position to within two centimetres. Initially they were big, clunky and very expensive but lately they have become smaller, easier to use and much cheaper. They need a small amount of IT infrastructure, but not much. I have one running in my garden shed using my home WiFi network and broadband Internet connection.

Understanding accurate GNSS systems involves a bit of theory, which I explain here