[Note: this should be illegal]
[Note: this should be illegal]
As the salty water meatbags move from room to room we change how the reflections and scattering patterns of 2.4 and 5GHz waves move. Studying these changes and some calibration, you can even determine small changes (like is the person on the left side of the room breathing, are they standing or prone, etc).
In their docs, they show using the WiFi connection from a printer to determine motion sensing and have the option to exclude pets.
For someone breathing or a heartbeat you need much higher GHz signal. Usually this is done at 30ghz to 60ghz. The power flux leaving the antenna has an inverse square drop off rate which makes this basically impractical unless your standing directly in front of it.
I'd really like to actually see it in person to really grasp the limitations.
> If you’d like to prevent your pet’s movement from causing motion notifications, you can exclude pet motion in your WiFi Motion settings by turning on the Exclude Small Pets feature. > Motion is detected based on the amount of signal disruption taking place between the Xfinity Gateway and your selected WiFi-connected devices, so motion from small pets (around 40 pounds or less) can be filtered out while keeping you notified of large movements more likely to be caused by humans.
It's an opt-in feature. If you don't set it up, they aren't generating the home/away chart like shown in the article.
If they find some way to sell the data you'll quickly find it difficult to opt-out of.