The microwave sensor applies the Doppler effect to detect moving objects using microwaves. This differs from the method used by a regular infrared (IR) sensor as microwave is sensitive to a variety of objects that are microwave-reflective, and its sensor readings are not affected by the ambient temperature.
This type of microwave sensor is widely used in industrial, transportation and civil applications such as measuring vehicle speed, liquid levels, automatic door motion detection, automatic washing, production line material detection and car reversing sensors etc.
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The microwave detection method has the following advantages compared to other methods:
Readings not affected by temperature, humidity, noise, air, dust or light - suitable for harsh environments
The microwave sensor can be useful together with other sensors to enhance its measurement accuracy. For example, Microwave sensor could decrease the pseudo fault report rate of human motion detection. And it does a good job in safety & security work.