Tightly-coupled GPS/UWB positioning

A tightly-coupled filter integrating GPS and ultra-wideband observations is implemented and tested in an urban canyon environment. Bias and scale factor errors in the UWB measurements are estimated in-run and used with GPS pseudorange and phase measurements to survey several corner points of an eight story building. Sub-meter level position solutions are maintained using tight-coupling in conditions where using GPS or UWB alone is unreliable or provides no solution at all.