RAK12007 is an ultrasonic sensor module based on the CS100, an industrial-grade ultrasonic distance measurement chip. This chip integrates an ultrasonic transmitter, ultrasonic receiver, and digital processing circuits. The distance measurement result output is in the form of pulse width. For an ultrasonic detector, there are two main parts: Emitter and Detector. The emitter transmits an ultrasonic sound wave, and the detector receives back the signal from the emitter reflected by an object. By calculating the travel time and the speed of sound, the distance of the object can be determined.