A method and system for determining a location of a vehicle, the method comprises determining reception location data within a first cell of a work area for a vehicle. A reception quality estimator estimates reception quality data for the corresponding reception location data for the first cell. Optical location data is determined within a first cell of a work area for a vehicle. An optical quality estimator estimates optical quality data for the corresponding optical location data for the first cell. A data processor selects at least one of the reception location data and the optical location data as refined location data associated with the first cell based on the estimated reception quality data and estimated optical quality data.