mmWave Presence Sensors: 24GHz or 5.8GHz? Complete Guide (Home Assistant + Zigbee2MQTT)

What actually changes between 24GHz and 5.8GHz

The key is how radio waves behave.

Basic rule:

The higher the frequency → the faster it reacts, but the shorter the range and the weaker the penetration.

That translates directly into how these sensors perform at home.

⚖️ Quick comparison

To make things easier, here's a quick look at the differences between both sensor types:

24GHz mmWave sensor: fast and accurate

This is the one that's gaining ground right now.

When to use it

• Bathrooms
• Small home offices
• Hallways
• Rooms where you want absolute accuracy

Real advantages

• Detects presence faster
• Prevents detection of people in adjacent rooms
• Better for critical automations (lights, alarms, etc.)

Typical problem it solves

If you have a sensor that turns on the bathroom light when someone walks by in the hallway...
👉 the 24GHz one is the solution.

5.8GHz mmWave sensor: more range and wider coverage

It's the “classic” option that's been used up to now.

When to use it

• Large living rooms
• Rooms with corners or nooks
• Open areas

Advantages

• Greater range (up to ~10m)
• Better behavior in complex spaces
• Less affected by obstacles

Weak point

• Can detect through walls
• More likely to produce false positives

Advanced setup (key to making them work well)

This is where most people go wrong.

These sensors are not “plug & play”. They need fine-tuning.

States you can configure

• Large motion → someone entering or walking
• Small motion → moving hands or head
• Static presence (stillness) → someone completely still

⚠️ Critical setting: the timeout

This is VERY important.

Even if they detect presence perfectly, they can still have millisecond micro-drops.

Recommended setting

• Timeout: 5 to 10 seconds

This prevents:

• Lights turning off while you're still sitting there
• Erratic automations

Home Assistant integration (Zigbee2MQTT)

They work perfectly with Zigbee2MQTT.

Most important entities

• presence → presence detected
• illuminance_lux → ambient light
• radar_sensitivity → sensitivity
• detection_distance → maximum distance

Real configuration example

After pairing:

1. You enable “permit join” in Zigbee2MQTT
2. You hold down the sensor button
3. It appears automatically
4. You rename it (important so you don't get lost later)

Example:

• Name: sensor_presencia_salon
• Entity: binary_sensor.presencia_salon_occupancy

Recommended settings (starting point)

• Sensitivity → low/medium
• Distance → set for the room (don't use the maximum)
• False negative filter → enabled if available

⚡ PRO tip (very important)

Don't start with high values right away.

👉 Start conservatively and increase little by little

Otherwise:

• It will detect movement outside the room
• You'll get constant false presence events

And what about battery-powered sensors?

There are new versions that work without a cable.

Clear advantage:

• You can place them wherever you want

Disadvantage:

• Less power and range
• Less accurate than wired models

🧠 Final takeaway

• You want accuracy and fewer mistakes → 24GHz
• You want to cover a large space → 5.8GHz

If you're unsure:

👉 In 80% of home cases → 24GHz is the better choice today

If you set sensitivity + distance + timeout correctly...
👉 you'll get practically perfect automations.

Where to buy

If you are interested in any of the options mentioned, here are the available links:

Presence sensor

• Tuya mmWave Human Presence Sensor Zigbee/WiFi — Reviewed in the video: Aliexpress
• MOES ZSS-HP05-A-MS — Equivalent alternative (Sin cables, a pilas): Official store · Amazon · AliExpress

Zigbee / Matter / Thread coordinator

• Tuya Smart Life Zigbee Hub WiFi + Bluetooth Multi-Mode: Aliexpress