Abstract: Systems and methods for determining the range from a vehicle to a plurality of reference points. In one system a mobile transceiver is located on the vehicle for transmitting a ranging interrogation signal pulse modulated on an RF carrier having a given frequency in response to a timing pulse and for receiving ranging response signal pulses modulated on RF carriers having the given frequency. A plurality of reference transponders are individually located at each of the plurality of reference points for receiving the timing pulse and the ranging interrogation signal pulse on a carrier having the given frequency and for responding thereto by transmitting a ranging response signal pulse on a carrier having the given frequency during an interval that is discrete from the intervals during which ranging response signal pulses are transmitted from the other reference transponders.