A low-cost dynamic range-finding device based on amplitude-modulated continuous ultrasonic wave

A practical low-cost acoustic range-finding method is presented, which provides a high-speed and high-accuracy solution for distance measurement. It is based on the linear phase delay of the received signal, with respect to the transmitted signal caused by the distance between the transmitter and the receiver. A continuous ultrasonic signal amplitude modulated by a low-frequency acoustic signal is used. The accuracy can be up to 2 mm within 1.5 m and the dynamic data update rate can be up to 150 Hz. The design principles, hardware implementation, experimental results, and performance analysis are included.