# mmWave radar enables presence detection without cameras - sensing human presence, movement, and even breathing through walls

**Date:** 2025-12-18  
**Tags:** SmartHome, Sensors, IoT  
**URL:** https://kelexine.is-a.dev/til/mmwave-presence-detection

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TIL: mmWave radar enables presence detection without cameras - sensing human presence, movement, and even breathing through walls. Unlike PIR sensors (motion only), mmWave detects stationary humans. Smart home applications: automatic lights that stay on while you're reading, sleep tracking without wearables.


```javascript
// mmWave presence detection capabilities
const presenceSensor = new mmWaveRadar();

const detection = presenceSensor.scan();
// Returns:
// - presence: true/false
// - distance: 0-8 meters
// - zone: which room region
// - activity: stationary/moving/sleeping
// - breathing_rate: BPM (for sleep tracking)
```




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*This content is available at [kelexine.is-a.dev/til/mmwave-presence-detection](https://kelexine.is-a.dev/til/mmwave-presence-detection)*