Vehicle position estimates by multibeam antennas in multipath environments

Vehicle positions in multipath environments are estimated from the angle of arrival of waves received by multibeam antennas installed at two base stations. The estimated root mean square (RMS) position error is about 350 m. This can be reduced to about 200 m by using two kinds of processes: the averaging of time series data and the averaging of two sets of data. The position estimate error is caused by reflection from buildings near the vehicles, and a large error exceeding 500 m is caused by reflections from high buildings located some distance from the vehicle. Precise estimation of vehicle position in multipath environments by measuring angle-of-arrival is difficult because of building reflection