Distance measurement principle of reversing radar

Parking radar is an auxiliary device for automobile parking safety, which consists of ultrasonic sensor (commonly known as probe), controller and display, alarm (horn or buzzer) and other parts. Ultrasonic sensor is the core component of the whole parking system, and its function is to send and receive ultrasonic waves. At present, the working frequencies of commonly used probes are 40kHz, 48kHz and 58kHz. Generally speaking, the higher the frequency, the higher the sensitivity, but the smaller the detection angle in the horizontal and vertical directions, so the 40kHz probe is generally used, and the ultrasonic ranging principle is adopted in the reversing radar. When the vehicle is put into the reverse gear for reversing, the reversing radar automatically enters the working state. Under the control of the controller, the probe mounted on the bumper at the rear of the vehicle emits ultrasonic waves and generates echo signals when encountering obstacles. After the sensor receives the echo signal, the controller processes the data, thus calculating the distance between the vehicle body and the obstacle and judging the position of the obstacle.