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Hey, I heard about how utility pole inspecting helicopters are able to tell the good/rotten state of wooden telephone poles by the reverb pattern of sound waves coming off the poles from the rotors -- it seems to me the whole field of non-invasive sensing (and using existing/ambient emission sources) is getting pretty impressive.

Can't help but think of the Star Trek TOS episode where Kirk is accused of murder and they find the "murder victim" in the ship by identifying and isolating heart beats until they discover he must still be aboard. It's been almost 60 years since the episode came out, but still sorry if that's a spoiler

Everyone’s heart is different. Like the iris or fingerprint, our unique cardiac signature can be used as a way to tell us apart. It can already be done from a distance using lasers [1].

[1] https://www.technologyreview.com/2019/06/27/238884/the-penta...

Apparently wifi can also see through walls:

https://news.ycombinator.com/item?id=37469920 (from the same org)

People are suggesting this to continuously monitor vitals. Others think that is a privacy problem. There might be an even bigger problem: continuous vitals monitoring might lead to over-medication and perhaps be worse for patients.

One of the reasons vitals are such a good diagnostic tool is that we monitor them specifically when we already suspect something might be wrong. Monitoring healthy patients reveals the large variation in vitals -- some that might even appear problematic.

We know this among other things because we have accidentally experimented on babies and mothers during delivery. Some clinics have a policy to put them on continuous monitoring the moment they arrive and they get treated for more things with worse outcomes when they're otherwise healthy. Maybe this is confounded (some clinics overmedicalise everything -- both monitoring and treatment) but I like the intuitive explanation that excess monitoring causes excess treatment.

802.11bf is working on sensing applications:

> With recent advancements, the wireless local area network (WLAN) or wireless fidelity (Wi-Fi) technology has been successfully utilized to realize sensing functionalities such as detection, localization, and recognition. However, the WLANs standards are developed mainly for the purpose of communication, and thus may not be able to meet the stringent requirements for emerging sensing applications. To resolve this issue, a new Task Group (TG), namely IEEE 802.11bf, has been established by the IEEE 802.11 working group, with the objective of creating a new amendment to the WLAN standard to meet advanced sensing requirements while minimizing the effect on communications. […]

* https://ieeexplore.ieee.org/document/10547188

> In recent years, Wi-Fi has been shown to be a viable technology to enable a wide range of sensing applications, and Wi-Fi sensing has become an active area of research and development. Due to the significant and growing interest in Wi-Fi sensing, Task Group IEEE 802.11bf was formed to develop an amendment to the IEEE 802.11 standard that will enhance its ability to support Wi-Fi sensing and applications such as user presence detection, environment monitoring in smart buildings, and remote wellness monitoring. In this paper, we identify and describe the main definitions and features of the IEEE 802.11bf amendment as defined in its first draft. Our focus is on the Wireless Local Area Network (WLAN) sensing procedure, which supports bistatic and multistatic Wi-Fi sensing in license-exempt frequency bands below 7 GHz (specifically, 2.4, 5, and 6 GHz). We also present an overview of basic sensing principles, and provide a detailed discussion of features defined in the IEEE 802.11bf amendment that enhance client-based Wi-Fi sensing.

* https://www.nist.gov/publications/ieee-80211bf-enabling-wide...

* https://www.cognitivesystems.com/how-does-802-11bf-enhance-l...

(See also perhaps IEEE 802.11bi, Enhanced Data Privacy.)

It's galling that this press blurb only focuses on happy (supposed) health monitoring benefits, and fails to address the privacy concerns in the slightest.

This can be abused in so many ways, like watching how people's heart rates change then watching an add, or browsing a selection of goods in the shop, and making viscerally targeted advertising. Or burglars detecting whether people are at home.

Soon we won't just have to worry about unpatched wifi routers being parts of botnes, we'll have to worry about them tracking our locations and excitement levels and selling them off to whoever.

I do it using MMWave sensor, 60Ghz one. Want to have more of them but installation is a pain as these need to be mounted on ceiling so WiFi based sensor would be awesome!

See

https://www.nature.com/articles/s41598-024-77683-1

That kind of module can be really cheap

https://www.waveshare.com/hmmd-mmwave-sensor.htm

and is starting to replace Passive IR sensors

https://en.wikipedia.org/wiki/Passive_infrared_sensor

I can imagine one of these on the ceiling above your bed being an ideal sleep monitoring system.

Hey guys I am the high schooler who developed this let me know if you got any questions I'd be happy to answer them

This is nothing new. Wifi signals have been used to detect objects, people and animals, gait analysis[1], read keystrokes[2], monitor breathing and heart rates[3], "hear" conversations[4], etc for at least a decade now.

https://news.ycombinator.com/item?id=12353605

https://www.theatlantic.com/technology/archive/2016/08/wi-fi...

https://archive.is/XnHUV

1: https://ieeexplore.ieee.org/document/7457075

2: https://dl.acm.org/doi/10.1145/2789168.2790109

3: https://archive.is/mFSDq

4: https://archive.is/sNVcM

This is the study https://bpb-us-e1.wpmucdn.com/sites.ucsc.edu/dist/d/1595/fil...

> Now, the researchers are working on further research to extend their technique to detect breathing [...]

Impressive from a technical standpoint, but super scary from a privacy standpoint. Surely this must allow them to detect and differentiate between plosives, which is probably enough to infer what's being talked about.

As someone that works closely with WiFi data and given their very low error (< 0.5 BMP MAE) I'd love to see them address a few key points:

- Whether train/test splits were participant-wise to avoid data leakage.

- How the system performs at elevated or highly variable heart rates.

- Results from "placebo" or empty-room baselines to rule out false positives, typically done with bags of rice/water (used to simulate mass).

There is a wonderful channel "Quantified Scientist" (https://www.robterhorst.com/, mostly YT content) with benchmarks of smartwatches and trackers against EEG and more profesional heart monitors. It would be interesting if he could benchmark WiFi as well.

AS, in short, it is easy to measure pulse or sleep somehow. It is hard to measure it well consistently (pulse when someone is running, biking or weightlifting, sleep when people sleep with others, move, etc - or lay sleepless).

This would be great for measuring heart rate while asleep because I can stand wearing a watch in bed, and my watch is charging at night as well.

Nobody:

Google: serves you Aspirin ads when they notice you are having a heart attack

Instantly visualises social media companies monitoring individual heart rates and heart-rate social graphs and that becoming an input into their algorithm ... scary shit.

They did this at MIT like 12 years ago.

So we can expect that comcast will soon be selling per-household sexual activity rate data to advertisers?

I think it's now fair to be concerned that future MAANG devices will use passive RF data mapping, triangulation, and harvesting to scan you, your environment, and others around you.

The future of individual freedoms can only be assured with open source software and hardware not beholden to the unbounded, extractive fetishes of governments and corporations.

Seeing that it works for a ESP32 chip I would say that its very likely to work on a smartphones's wifi chip though the article didn't say. Many people carry phones with them everywhere and all the time. You could build a very impressive profile of a person. It could be used to see when they get excited, scared, angry, etc at depending on what they view on the phone, the phone call they received, where they physically located on the earth, who they are around (by looking at identities of other phones near them) and properly other things as well I have not thought of.

So how long until my ISP starts selling McDonald's data on how my heart rate reacts to their new commercials that my ISP got based on wifi signals?

No clunky wearables? No chest strap on the treadmill? Heart rate and respiration? Monitors everyone in the house simultaneously 24/7 on a cheap rpi? I hope this doesn't take years to come to market because this seems incredibly useful.

This is just a dedicated RF emitter combined with a dedicated receiver. The fact that is it uses WiFi hardware is probably just because that's the cheapest and most available hardware for the researcher to work with. There is no indication in the article that the WiFi can actually be used for transmitting real data at the same time; that a non-dedicated WiFi source can be used; that it works when there are many people between transmitter and receiver.

Therefore the ideas that this might apply to real-world situations and use existing WiFi infrastructure, are a stretch given the information that's been shared.

It basically doesn't seem like a big deal to demonstrate what has been demonstrated.

Someone point this at Trump and report back

Find your target by heartbeat. Fly to heartbeat. End heartbeat.

Wake me up when it can find me in the crowd.

Its a good effort but very pedestrian and a very low hanging fruit. Its just another academia paper that will be published.

https://doi.org/10.1109/GLOBECOM38437.2019.9014297 https://doi.org/10.1109/CCNC.2018.8319181 https://dl.acm.org/doi/abs/10.1145/3286978.3287003 ..... many more.

I'd say this is far more interesting, does not use ML and credits the tech stacks that it leverages . https://people.csail.mit.edu/davidam/docs/WiMic_final.pdf

there’s always a cost to the organ being read, will this one day become a way to monitor a crowd for individuals of suspicious activity? scary tech, eventually along this technological trajectory the computer effectively reads your mind by combining biometrics with user profile data and large models, even though it will just be a prediction, a very informed prediction

I guess it is good to be aware of what’s possible. But all this stuff about using WiFi to measure things about people—it’s a bit creepy, right? I mean, to state the obvious, we (as a society) have got a bunch of poorly patched or corporate controlled WiFi routers attached to the network. What a surveillance catastrophe waiting to happen.

I mean, heart rate? Do we have a giant network that can tell where everybody is and whether they are having a strong emotional response to anything?

I wonder, if this would work with bluetooth, too. Would be nice to hack e.g. the new, cheaper version Pebble watch to measure heart-rate this way. I mean, possibly this could even be superimposed on the regular BT-connection signals. I presume open firmware would enable these sort of things.

There are products already that do this: https://www.originwirelessai.com/

New polygraph just dropped.

This would be great to be able to log and monitor heart rate data while sleeping without needing to wear a wearable.

I think soon it will be time to seriously consider eliminating use of Wifi in some private places and going back to speed and reliability of copper wires. WiFi is like basically illuminating an area in light that can pass through walls.

What else can it measure?

Voice recording should not be an issue?

Thanks, now I need to build a faraday cage around my chest to stop the CIA from polygraphing me at range.

Bros at UCSC must be getting some good grants from the US military. I can already imagine the next gen of public-wifi driven drone strikes

WiFi equipment can see your heart beating, but don't worry, it cannot possibly have any harmful effects on human physiology.