mmWave radar with Home Assistant and ESP Home
Erwin.Redl 2026-04-10 02:20:32 26 Views1 Replies Dear friends @ DF Robot!
I am working on an interactive art installation in the US with 24 sensors providing information about people in certain sections around the art installation. I bought two of your SEN0395 mmWave Radar 24GHz Human Presence Detection Sensors and interfaced with them through the Arduino platform.
Now I am trying to integrate the sensors into the art installation with Wifi or other OTA options. I stumbled over an article by Jaychouu in Autodesk Instructables about "Building a Native Home Assistant MmWave Presence Sensor With ESPHome on ESP32-C6" see https://www.instructables.com/Building-a-Native-Home-Assistant-MmWave-Presence-S/. I think Jaychouu actually works for DF Robot :)
It looks like the Home Assistant Green in combination with the C4002 mmWave sensor and the FireBeetle 2 ESP32-C6 would already a tested and proven solution for my project.
I now have a couple of questions about this setup:
- Sensor: Would the SEN0395 sensor work the same way as the C4002 sensor with the FireBeetle 2 ESP32-C6 and the Home Assistant Green?
- Sensor differences: What are the main differences between the SEN0395 and the C4002 other than the larger beam angle and slightly larger distance of the C4002?
- C4002 sensor details: Can you narrow the beam angle of the C4002? Does it have different "sections" that can be turned off? I actually would need a more narrow beam angle.
- Sensor quantity: Can the Home Assistant Green handle 24 sensors?
- Home Assistant Green reach: How far does the Assistant's Wifi reach? How far away from the Assistant can the sensor with the Firebeetle 2 ESP32-C6 be placed?
- FireBeetle 2 ESP32-C6 IoT Development Board: It looks like it is only "pre-order" at the DF Robot store (DigiKey has a lot in stock, though).
- Would the FireBeetle 2 ESP32-C5 IoT Development Board work as well with the sensors and the Home Assistant Green?
Thank you for your help in advance!
Erwin
Hi Erwin,
Thanks for sharing your awesome interactive art installation project! Here are the quick answers to your questions:
1. Sensor Compatibility
Both SEN0395 and C4002 work with FireBeetle 2 ESP32-C6 and Home Assistant.
• SEN0395 supports basic ESPHome configuration and only outputs simple presence / no presence status.
• C4002 has native ESPHome integration, allowing you to adjust detection range and sensitivity directly in Home Assistant without extra coding or calibration tools.
2. Key Differences (beyond beam angle & range)
• SEN0395: Only detects basic human presence (binary output).
• C4002: Detects moving / static human presence, plus extra data like speed, direction, ambient light, etc., for more precise sensing.
3. C4002 Beam Angle
The beam angle can't be adjusted electronically. You can only narrow it by physical shielding; the sensor supports adjusting detection distance only.
4. 24 Sensors Support
Home Assistant can handle 24 sensors with no technical issues.
5. Board Compatibility
FireBeetle 2 ESP32-C5 is fully compatible and can replace ESP32-C6. Also, FireBeetle 2 ESP32-C6 (DFR1075) is in regular stock, not pre-order.
For more ESPHome details, check the official docs: https://esphome.io/components
Yx 