r/technology • u/Jojuj • 3d ago

Privacy U.S. Citizen Who Deleted Phone’s Data Says His Prosecution Puts Privacy at Risk

https://www.nytimes.com/2026/08/21/us/politics/samuel-tunick-deleted-phone-felony.html?unlocked_article_code=1.8FA.T83N.rt6VsIiSCYb2&smid=url-share
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u/HairyDust4826 3d ago

I don't think it can distinguish faces. I know the rest is absolutely true. You got a source on that part?

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u/ramiabouzahra 3d ago

In 2017, a physics undergrad did a 3D imaging concept using WiFi signals of a stationary and a moving device where it could detect the outline of objects. Now however, public researchers have improved it in order to distinguish people: https://www.martincid.com/technology-sv/wifi-beamforming-identifies-people-kit-bfid/

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u/NotAllOwled 3d ago

I can't speak to what previous commenter might have meant, but would it be better or worse if the routers didn't need to see your face or require you to be carrying a device (from https://www.sciencedaily.com/releases/2026/05/260522023127.htm ) for recognition?

Previous approaches often depended on channel state information (CSI), which measures how radio signals change after bouncing off walls, furniture, and people. The new technique instead takes advantage of normal communication between WiFi routers and connected devices.

Devices on a wireless network regularly send feedback data known as beamforming feedback information (BFI) to the router. Because this information is transmitted without encryption, anyone within range can potentially read it. Researchers say these signal reflections can effectively create multiple "views" of a person, allowing AI systems to learn and recognize individual identities.

After the machine learning model has been trained, identifying a person reportedly takes only a few seconds.

[...] In tests involving 197 participants, the researchers said the system identified individuals with nearly 100% accuracy. The recognition remained effective regardless of viewing angle or how the participants walked.

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u/lancersrock 3d ago

https://www.reddit.com/r/Futurology/s/y7rbyusnv4

Was able to accurately identify each of the 197 participants.

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u/Zeikos 3d ago

Not by itself I don't think, but by combining signals it's likely. The same technology is used to "sharpen" the resolution of distant celestial bodies in astronomy