This has already been an area of research, both publicly, and most likely in private/government defense research. In a targeted situation, i.e. surveillance of a household of 6, this would work easily enough...but I doubt there is enough information to provide reliable (high AUC) tagging of ID in a public scenario oh hundreds to thousands of individuals.
> Researchers in Italy have developed a way to create a biometric identifier for people based on the way the human body interferes with Wi-Fi signal propagation.. can re-identify a person in other locations most of the time when a Wi-Fi signal can be measured. Observers could therefore track a person as they pass through signals sent by different Wi-Fi networks – even if they’re not carrying a phone.. their technique makes accurate matches on the public NTU-Fi dataset up to 95.5 percent.
That’s 95.5% accuracy with a 16 person dataset in a highly constrained environment.
Wi-Fi uses long wavelengths, you can cancel out the noise with one person but crowds are all distorting the same very weak signal here. 5Ghz = 6cm, visible light is 380 to about 750 nanometers.
Xfinity's is sensitive enough to configure for animals or humans under 40-70lbs, I forget the exact number.
From my minimal research, it could be pushed a lot further.
What I'm particularly interested in is the edge case scenario of duplexes and apartments, where neighbors are unwittingly subjected to surveillance. There is little more to their routers than firmware to impart these capabilities. No reason to think it won't become common, and there are a handful of other companies basically offering just this as a service.
Strange times.
Edit: I should have mentioned the obvious, that pesky thing no one wants to address... When AI is added to this tech, it will get grotesque. Gait recognition, behavioral patterning, etc. Not something to sneeze at.
Possibly what was used to watch Maduro, along with synthetic aperture radar etc.
if it's a public scenario, you don't need that, they're using wifi on people's persons to id them. The concern is more gait analysis, and by some accounts even lip reading is possible with mm-wave 5g.
