Patent ID: 7720598

Claim:
A method for determining a position of a vehicle, the method comprising: transmitting a transmission signal from a mobile transmitter at the vehicle to beacons at different sites associated with a work area; determining respective elapsed times for corresponding propagation paths between the vehicle and the beacons, each propagation path including at least one of a first propagation duration and a second propagation duration, the first propagation duration referring to a first propagation time of the transmission signal from the vehicle to a particular beacon, the second propagation duration referring to a second propagation time of a return signal from the particular beacon to the vehicle; compensating for error associated with a corresponding propagation path by invoking a linear fit scheme, the linear fit scheme applying a generally linear fit over fixed intervals of noisy position measurements to generally conform to a linear portion of a path plan of a vehicle to be tracked; and estimating the position of the vehicle at least near a confluence of position curves based on elapsed times for the propagation paths, where the position curves are fitted to a generally linear progression of a planned path of the vehicle in accordance with the compensation to obtain the estimated position.