Microwave induction automatic light turning circuit

Shown is a microwave induction automatic light-on circuit. In this circuit, after the power is turned on, the antenna of IC I will emit microwave signals. When a person enters the detection area, the signal reflected by the human body is also received by the antenna . There will be a phase difference between the transmitted and received signals, and the circuit will The phase difference detected becomes the signal that drives the operational amplifier and is output from the @ pin of IC1. After being processed by IC 2, a pulse signal is formed that triggers the bidirectional thyristor. The thyristor is turned on and the light is lit. When people leave the detection area, there is no signal output and the light automatically goes out.