An Investigation of tightly-coupled UWB/low-cost GPS for vehicle-to-infrastructure relative positioning

Abstract

A method for tightly-coupling carrier-phase differential GPS with ultra-wideband (UWB) ranging for vehicle-to-infrastructure relative navigation is proposed. Relative position, velocity, clock errors, GPS phase ambiguities and UWB systematic errors are estimated using an extended Kalman filter. The method is tested with real data and evaluated in terms of position accuracy, GPS float ambiguity convergence, time to fix ambiguities, and correctness of the ambiguity solution. Performance with geodetic and consumer grade GPS receivers is compared. The effect of UWB operational range and the number of available UWB ranging sources is also evaluated.