The main differences between microwave radar sensor switches and PIR infrared sensor switches

The main differences between microwave radar sensor switches and infrared sensor switches lie in their working principles, sensing range, and environmental adaptability. 

Here's a breakdown of the key differences:

1. Working Principle

• Microwave Radar Sensor Switch: Based on the Doppler effect, it uses high-frequency electromagnetic waves (usually microwaves) to detect moving objects. When an object moves, the microwave frequency changes, which the sensor detects and triggers the switch.

• Infrared Sensor Switch: It uses infrared radiation to detect heat sources, typically the infrared radiation emitted by the human body. When a person enters the detection range, the sensor detects the temperature change and triggers the switch.

2. Sensing Range

• Microwave Radar Sensing: Has a wider detection range and can penetrate some non-metallic materials (such as glass, plastic, thin wood, etc.). It is suitable for indoor and some outdoor scenarios, especially in areas not in direct line of sight.

• Infrared Sensing: Has a narrower range and primarily relies on detecting heat sources within the line of sight, and it cannot penetrate objects. It is best suited for enclosed areas.

3. Environmental Adaptability

• Microwave Radar Sensing: Not easily affected by external factors like temperature and humidity, making it stable in various environments (e.g., high temperatures, low temperatures, outdoor scenarios).

• Infrared Sensing: Sensitive to environmental temperature. In high-temperature environments, it may struggle to distinguish human body heat, resulting in reduced sensitivity.

4. Stability and False Triggers

• Microwave Radar Sensing: It can be overly sensitive to any moving object, which may result in false triggers (e.g., pets or moving leaves).

• Infrared Sensing: Has a lower false trigger rate as it primarily reacts to objects with a certain temperature (like humans or animals).

5. Application Scenarios

• Microwave Radar Sensor Switch: Ideal for corridors, parking lots, and areas that require a wide detection range.

• Infrared Sensor Switch: Suitable for homes, offices, and places where precise detection of human movement is needed.

In summary, microwave radar sensing is better suited for larger areas and non-line-of-sight scenarios, while infrared sensing is more appropriate for stable, enclosed environments.