In open sky, modern GNSS receivers are accurate to a few metres or better. Between tall buildings, signals are blocked and reflected, and errors can grow to tens of metres.
What goes wrong
Multi-band and multi-constellation receivers help by giving the receiver more signals to choose from, but they do not remove reflections entirely.
Testing for real cities
Reliable results come from combining lab simulation with drive tests on routes that include dense urban areas, tunnels and parking garages, measured against a high-precision reference system.
Related serviceGPS & Location Testing →
