If all you need is presence detection then a motion sensor would be vastly more efficient.

If you actually need identity detection, then maybe, but you'll still have to have a camera or detailed access logs to associate the interference signature with a known entity and at that point you may as well just put an RFID reader under the bowl you throw your keys into or use facial or gait detection.

"Hey boss come look. This microwave is walking around again"

ALERT ALERT ALERT

Sorry dude I forgot to add your bio signature to my WiFi router.

I can imagine this being initially an accidental discovery like oh every time so and so’s body interacts with the WiFi signal it’s the same pattern… until someone starts exploring this further… and then some engineer or their manager started looking for applications for this. In my experience engineering researchers especially are very good with coming up with use cases for whatever tech they’re working with, with little ethical consideration.

I believe the reason they had to say "up to" is because the "signatute" will vary day to day ever so slightly (natural weight fluctuation), and if you gain or lose weight it can change dramatically, so the AI would have to constantly consider that and adjust it's records.

Honestly, unpopular opinion, but as long as it isn't very short wavelength RF and they allow for self-hosted/open-source alternatives, I do find it a bit more privacy respecting than cameras, of course they have to say they are using the technology in public places.

It also has it's ways of fooling it, instead of wearing a wig and a false nose, you could wear a carbon-infused silicone fat suit to change the way you interact with RF.

Stilsuits: get it for the unbearable heat as we turn the Earth into a desert, now with wifi blocking!

Being able to scan and model a 3D environment using wifi? Sure. Wifi-fingerprinting the people in the scan? Why?

There is no end user need or product for being able to identify individuals based on their interactions with WiFi signals

Cat tracker

Yes, according to your wifi fingerprint, you had.
https://www.youtube.com/watch?v=aQn9L-wkq_c&t=1m29s

Why do you need to identify specific cats over merely the presence of movement or cats in general?

Because I want to know which cat is getting up to shit they shouldn't

There's a yo mama joke in here somewhere, I can feel it.

Well I heard about this and thought "this will be great for home automation", but I also know that someone was equally excited about using this to rob people of basic freedoms or being a fucking creep or both.

I doubt it. You'd need to be looking really closely at the waveforms to notice this, so they were likely already doing something similar, like that research that can pinpoint where people are in a house based on their WiFi. They were probably already doing something creepy before they noticed that this was more straightforward than they expected.

I mean I don't understand this as a lay person, so if it doesn't work then fair enough, but if wifi signals can identify human beings, and pets, when a building collapses better than other methods, or even augment the capabilities already used, then at least there is some benefit from this technique. It's not going to disappear, Genie is out of the bottle now, so why not at least put it to a good use instead of keeping it only being abused by the billionaires and other evil entities.

It's too late now to stop that and I hate that they can do this.

Please don't mistake me trying to find a silver lining as anything other than trying to find a reason that this isn't just another way we are fucked but the science is what it is so out it to better use. It's an interesting capability regardless of how it can be abused, and since we aren't going to stop using the technology we should really understand exactly how this works by using it and making it was beneficial as possible.. Until we were ready to ban the tech, which I have no faith that we will ever.

A bespoke device made to do this, not just your wifi router at home, might as well study it for good praises, or we may if only be abused with little defence against our collective abusers

Legendary reference

Once you start playing with radiowaves and antenna you start noticing the intricate ways it plays with and around bags of water like bodies. I'm sure the original research on location/movement tracking was due to scientists trying not to get interference, later once they figured it out it was natural to see how much data they could get out of a radio interference profile.

I remember the original tech was going to be marketed as a way to tell if your old person (parent etc) had fallen down and stopped moving. Not the best use case, and then the privacy implications became clear. Once that happens the race begins to exploit the tech.

...But the eventuality here is something like a Star Trek tricorder that can take multiple vitals and detect irregularities from across the waiting room. Sensors that remember who was in a room and what settings they had. Etc. Some cool thing besides the bad stuff (microtarget those ads).

All time is poo time when you're close to the boss's desk

The resulting image must just basically look like a shadow, I can't imagine that they're going to get much internal detail with Wi-Fi considering that my router's signal practically gets blocked by a piece of cardboard.

This research essentially amounts to, humans can be individually identified with nothing more than low quality x-rays. Well yeah, so what, you can also use visible light and in any situation where you're going to use Wi-Fi to detect someone, it's got to be easier to buy a cheap CCTV camera.