Hi all,
I have read that nowadays it is possible to detect the presence of persons in the room simply by measuring fluctuations in the wifi net, I believe that Philips mentioned something like this the last year but not sure. Is anybody having experience with this? Anything open source?
Thanks
It is technically possible in a lab environment, but the feature is not (yet) present in real-world consumer hardware.
(yes, technically doing all this without any cooperation from APs & Co. is also possible, but shifts the complexity (costs) significantly towards the receiving end).
Hue has this available now for zigbee (“MotionSense”, IIRC). I only have a couple rooms that have the minimum # of required bulbs with adequate positioning for it, and it’s not mind-blowing.
It does detect major motion movements OK, but it’s not fast enough or consistent enough that I’d use it as a primary trigger for anything. I’m sure having more eligible devices spaced around would help, but I’m skeptical the improvement would be that significant 
It most definitely does not detect presence/occupancy at the level mmW does - at best, it’s comparable to a less-than-stellar PIR detector. But who knows what future improvements could bring - it’s definitely an intriguing use of that radio spectrum!
Give ESPectre a try. I just released v3.0.0-rc1. It runs on a cheap ESP32 board and works with Home Assistant. The person does not need to carry a phone or tag, and no radar module is required.
It evaluates Wi-Fi channel state changes and publishes a fresh movement score every 250 ms, so the feedback feels almost immediate.
There are two detector profiles: Lightweight, which uses fewer resources and suits most cases, and High Accuracy, based on a neural-network model I trained. Everything is open source.
We also have a new website: espectre.dev 