US7679996B2
Methods and device for ultrasonic range sensing
A system and method for sensing proximity of an object includes a signal generator, which generates a plurality of signals. A transducer is in communication with the signal generator to receive the plurality of signals from the signal generator. The transducer is capable of transforming a plurality of signals from the signal generator into a plurality of ultrasonic waves. The plurality of ultrasonic waves includes a first ultrasonic wave and a second ultrasonic wave, wherein the first ultrasonic wave and the second ultrasonic wave are formed out of phase. The plurality of ultrasonic waves are directed toward and reflected by the object. The transducer receives the plurality of ultrasonic waves reflected by the object, which become a plurality of received ultrasonic waves. An analog to digital converter is in communication with the transducer. The received plurality of ultrasonic waves reflected by the object is communicated to the analog to digital converter by the transducer.
