A proximity sensor for determining a position of an object. The proximity sensor includes a SAW device having a load end and an input end for receiving an input pulse. A sensing section connects to the load end of the SAW device. When the object is in a first position, the sensing section provides a first response indicative of the first position and, when the object is in a second position, the sensing section provides a second response indicative of the second position such that the position of the object can be determined based upon the response to the input pulse.