[sponaugle]

This is a VERY controlled environment - and they used 20 passes of each person walking with direct knowledge of each person to train for identity. They did no tests with multiple people walking at the same time, or with any other external moving distortion effects (doors opening, etc) . This is very far from actual 'identification' of people in real public settings - and no doubt the cell phone everyone is carrying with them offers many orders of magnitude better opportunity. In a real crowded environment this would be nearly worthless.

The devices that reported BFI information were also stationary, and there were no extra devices transmitting information that would be conflicting.

A single camera would be much more effective.

[notepad0x90]

Yes, but things could be refined. With more resources and research thrown at it, it could become more versatile, that's why the title of the post says "could". And chances are, there are private and government entities already doing this. Research like this has been coming out for at least a decade now.

Even Xfinity has motion detection in homes using this technique now:

https://www.xfinity.com/hub/smart-home/wifi-motion

[SubiculumCode]

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.

[thesuitonym]

Yeah, it can and will be refined, but the major limiting factor is resolution. Wi-Fi radio waves are just too big to get a very clear image.

[Aurornis]

> Even Xfinity has motion detection in homes using this technique now

WiFi presence detection is a completely different problem. If the WiFi environment is changing past a threshold, return a boolean yes or no. It can't actually tell if someone is present or if the environment is just changing, such as a car driving close enough to reflect signals back in a certain way.

Doing mass surveillance where you detect individual people in a random home environment isn't the same thing at all. All of these "could" claims are trying to drawn connections between very different problems.

[sandworm101]

Only if wifi is radically increased in frequency, power, directionality or antenna size. And i mean way beyond practicallity. It would be easier to identify people by the sounds of thier footsteps, something easily done through anything with a microphone. With three microphones, you can track that movement to the inch.

[woodrowbarlow]

the article is off-base with wifi. the real story is in 6G cellular.

there is a working group at 3gpp, an EU-funded research group (6th sense, Open6GHub), universities (NCSU, Bristol), and many companies working very hard right now on proposals to include "integrated/joint sensing and communication" (ISAC/JCAS) in the 6G spec.

ISAC means adding mmWave to 6G (ostensibly for speed, but also) to build a high-fidelity 3d realtime "digital twin" of the real world that can see through walls, owned and operated by your telecom provider.

> A very exciting innovation that 6G will bring to the table would be its ability to sense the environment. The ubiquitous network becomes a source of situational awareness, collating signals that are bouncing off objects and determining type and shape, relative location, velocity and perhaps even material properties. With adequate 6G solutions for privacy and trust, such a mode of sensing can help create a “mirror” or digital twin of the physical world in combination with other sensing modalities.

https://www.nokia.com/about-us/newsroom/articles/nokias-visi... https://www.bell-labs.com/institute/blog/building-network-si...

there's been a testbed deployment in a German hospital for "non-invasive" monitoring of vitals; which sounds to me like it can literally see a heartbeat.

https://www.nokia.com/about-us/news/releases/2024/12/17/noki...

truth is, this is the nature of wireless radios. we can't keep improving bandwidth and latency without also turning the radio into a camera. i'm disturbed by the inevitability.

[protocolture]

> ISAC means adding mmWave to 6G (ostensibly for speed, but also) to build a high-fidelity 3d realtime "digital twin" of the real world that can see through walls, owned and operated by your telecom provider.

"See through walls"

There used to be a great video on youtube of a very high power 60GHz signal being blocked by a door. Sad I can never find it. E Band isn't much better.

IIRC the 60GHz radio is being left out of a lot of 5G deployments because the slight benefits don't outweigh the cost.

This is a pretty common thing for mmWave (or near mmWave) to be deployed with massive fanfare and then be slowly phased out of existence. I am decidedly not writing this on a WiGig docking station.

I dont see telcos wanting to constantly broadcast extra mmWave for little to no added benefit, especially not in all directions. Likewise, regulators are going to choke on that. And the class/band license schemes would have to be updated, to remove interference from devices already using those bands as they are about to have a constant background level of interference. E-Band PTP users, of which there are many, wont give up their high capacity links to weird 6G omni broadcasts without a fight.

I tell you what however, having a button you can press that would map the environment for alignment sounds like a maybe use case here. Better than a camera for detecting new obstructions when links go down.

They might also add more bands to the whole automatic MIMO backhaul trick they have been pursuing.

[Ancapistani]

Great. Now you’re telling me the chicken wire embedded in my walls isn’t sufficient, and I’m going to have to go with grounded sheet metal?

[testplzignore]

Bruce Wayne implemented this almost 2 decades ago in The Dark Knight. EU innovation moving at a snail's pace as usual /s

[mahrain]

Yes, you won't be able to do this on normal wifi traffic typically either, you need to send specific packets at a high enough rate (in between normal internet traffic) in order to sense with any accuracy, as I also remarked earlier: https://news.ycombinator.com/item?id=46976849

[sponaugle]

Yea, that makes sense as you would need quite a bit of information across a reasonable temporal range if the identifying qualities are movement related. Very interesting.

[dylan604]

There'll be an update where a first responder can send a special packet to an SSID that will enable these high rate packets without needing to join the wifi. It'll be secure where only the good guys will know about it so that it won't be able to be used nefariously. /s

[culi]

Yes but this is just the start and its already good enough for an ICE car to park outside your house and check if you're home and what room you're in.

[scottLobster]

They can do that by looking at the cars in my driveway/garage and or just watching the windows for any period of time. Plus my phone. If <insert 3 letter agency> agents are sitting outside of your house, they aren't going to drive away because you pull the plug on the router and suddenly deprive them of BFI packets.

[Aurornis]

Exactly. All of these stories using WiFi to detect things with high accuracy are just extreme machine learning demos.

Given a tightly controlled environment and enough training data, you can use a lot of things as sensors.

These techniques are not useful for general purpose sensing, though. The WiFi router in your home isn't useful for this.

[t-3]

WiFi AP's already do a lot of tracking and measurement just to improve signal fidelity and effective throughput. Why wouldn't those same techniques be useful for more general object tracking? Of course using a single AP to attempt to track movement in real-time is unlikely to have great results, but with several APs and enough compute triangulation should improve results.

[gentleman11]

today's tech demos are tomorrow's everyday

[BatteryMountain]

Unless they start storing data about your specific gait & posture, skull shape, limb dimensions and build up a "fingerprint" of your body.

[hsbauauvhabzb]

You mean like those scanners at the airport?

[spyder]

Yes it's in a controlled environment not in a real world noisy environment. But this is more stealthy than a camera and could potentially work with non-line-of-sight or even through walls.

And based on that I could imagine with a combination of a camera and this method, you could train the model on data where both the camera and this method is seeing the individual and then continue to track them with the wifi sensing + the trained model even where the camera cannot see them anymore.

But yea real world is noisy, so it could be very challenging.

[IshKebab]

Yeah this is one of those "cool demo" research results that is completely impractical in the real world that is sold (probably by university PR departments) as an actual viable technique that might have real-world implications.

We've seen it before with things like taking photos around corners.

And no, it isn't like the Wright flyer and a bit crap now but in 40 years we have jet planes. This will never get significantly better.

[jajuuka]

Yeah I've seen this same type of study done over the years with the same dire warning. But like you pointed out it's just extremely labor intensive when it's simply easier to attack phones, security cameras or any other smart device that can be easily hacked. Or just install your own bugs.

Would not be surprised to see this get more traction right now due to the political climate.

[Fnoord]

If I was interested in mass surveillance I would combine the radio data (WLAN, BT, ...) with the camera feed. If you then see the same person with ML, you can correlate that with radio's. You can even do that with cell towers with anonymous SIM, especially if combined with public transport camera feed or ALPR/ANPR.

[niobe]

HEADLINE: Electromagnetic radiation can be used to see!!!!

Right, that's what your eyes do. Radio is much longer wavelength than visible light (~5-10cm). So at best it offers extremely crappy resolution unless - you're doing something clever with second order information.

[vasco]

Well nowadays you individually track by using mac addresses and other network information from the devices within range. Cisco has some creepy real time maps of your location with each person walking around and all their previous visits etc

[K0balt]

Saw a system like this at a Podunk, nowhere, USA police station over a decade ago. It had high fidelity maps of peoples comings and goings based on Bluetooth and WiFi MAC IIRC. And some kind of API backend to look up identity based on those identifiers, not sure to who.

You could for example flag a location (house) and get a list of all of the comings and goings over the last x months, then look them up by identity. You could also flag when an individual was in proximity to another, or when someone turned on, off or switched phones.

I’m sure it amounted to illegal surveillance and would be inadmissible if any of it was done without a warrant, but it would be beautiful for parallel construction. (How is that even constitutional???)

It apparently relied on some kind of infrastructure deployment that consisted of “traffic cameras” and “satellites” ( I’m certain not of the spacecraft type) that I assume were just small receivers mounted on street lights, since the streetlights were almost completely replaced at the same time as the cameras were put in, by the same out of state contractor.

I was there to change out a bad SSD and do a RAM upgrade on one of the servers. I don’t imagine the technology has become less invasive.

If you have a phone or carry active Bluetooth devices, assume you are 100 percent tracked 100 percent of the time.

[avidiax]

Modern phones connect with a randomized MAC address. So yes, you can track a person around, but you will need another system (like the WiFi login page) to match MAC to identity.

[Modified3019]

When it comes to capability, the phrase “it’s the worst it’s ever going to be” comes to mind.

[wcunning]

This is going into the next Wifi standard specifically to get this data off of normal wifi traffic.