Vaguely similar, since electrical wires emit EM fields that are disturbed by human bodies, you can use a special camera to see who's in a building based on those disturbances. I'm not sure how high-fidelity or easy to spoil it is, but this was real technology at least 15 years ago.

xfinity is now selling a security product based on seeing people in your home with Wi-Fi signals

This is a feature in modern wifi routers and every single one is capable of detecting presence of multiple people within an apartment. With some training, movement can be distinguished from the data.