Hardware Design Schematics for Testing Echo Sensitivity and Ringing in ET (Enclosed Pulse Transit) Type of Ultrasonic Transducers.

The report details the implementation of distance measurement system using the ultrasonic waves. As the human ear’s audible perception range is 20 Hz to 20 kHz, it is insensitive to ultrasonic waves, and hence the ultrasound waves can be used for

ULTRASONIC PROXIMITY DETECTOR...We the humans can hear sound of up to 20kHz frequency only. This proximity detector works at a frequency of 40 kHz. It uses two specially made ultrasonic transducers: One transducer emits 40kHz sound, while

基本常识，翻译英文，主要是讲一些理论的测距原理-[8] Piezoelectric Micromachined Ultrasonic Transducers Based on P(VDF-TrFE)