A microwave sensor is an electronic device designed on the theory of sound wave's Doppler effect, and can be used to control LED lights.
The main parts of a sensor are microwave oscillator,microwave-transmitting antenna and microwave-receiving antenna.
microwave oscillator generates microwaves, microwave-transmitting send the microwaves, which bounce off surfaces and return to microwave-receiving antenna, then the microwaves signal turns to be electrical signal, which produce the corresponding switch operation to control the LED lights. All of the process gets down in a very short time.
Microwave sensor is of strong anti-rf interference ability , not affected by temperature, humidity, light, air flow, dust, etc. Because of the penetration characteristics of microwave, microwave sensor can be install inside the LED lights.