Wi-Fi Devices as Physical Object Sensors

The new 802.11bf standard will turn Wi-Fi devices into object sensors:

In three years or so, the Wi-Fi specification is scheduled to get an upgrade that will turn wireless devices into sensors capable of gathering data about the people and objects bathed in their signals.

“When 802.11bf will be finalized and introduced as an IEEE standard in September 2024, Wi-Fi will cease to be a communication-only standard and will legitimately become a full-fledged sensing paradigm,” explains Francesco Restuccia, assistant professor of electrical and computer engineering at Northeastern University, in a paper summarizing the state of the Wi-Fi Sensing project (SENS) currently being developed by the Institute of Electrical and Electronics Engineers (IEEE).

SENS is envisioned as a way for devices capable of sending and receiving wireless data to use Wi-Fi signal interference differences to measure the range, velocity, direction, motion, presence, and proximity of people and objects.

More detail in the article. Security and privacy controls are still to be worked out, which means that there probably won’t be any.

Posted on April 5, 2021 at 6:15 AM36 Comments


Schadenfreude April 5, 2021 8:00 AM

Imagine a world where the police can reconstruct a crime based on this technology.

Also, imagine a world where your neighbours are watching your every move.

Security and privacy controls are still to be worked out, which means that there probably won’t be any.


yet another Bruce April 5, 2021 8:47 AM

WiFi has a proud history of having access control and data encryption that is almost but not quite good enough. I am sure 802.11bf will uphold this tradition but I don’t believe that this is what you all are concerned about.

Since Heinrich Hertz first published a proof of concept exploit over 100 years ago numerous organizations have taken advantage of an undocumented feature of electromagnetic propagation that allows an attacker to use radio waves to detect objects and determine their range. Worse yet, the maintainers of the widely used electromagnetic propagation library do not seem to have even the most rudimentary bug tracking process in place and have proven impossible to contact.

I am not sure exactly what sort of privacy and security solutions you would put in place in an ideal world. Please share.

Humdee April 5, 2021 8:53 AM

It’s more than the fact that there won’t be, it’s how can there be? Not unless someone develops the wi-fi equivalent of an invisibility cloak.

Besides it won’t stop, there…take wi-fi, extend its range, put it on a satellite in low orbit and one has the ultimate spy device. It’s not science fiction any more to think that with sensing improvements and big data that before long someone will be able to create a 3D model of every movement on earth in real time.

Marvin April 5, 2021 8:54 AM

This will make what has been a police/FBI/spy capability into something all of us can use.
Google and Amazon are going to love it! They’ll add it to all their IoS stuff.

Dingi April 5, 2021 10:18 AM

Thank you for your tremendous efforts in this wonderful piece of work. Be proud of the fact that you have the ability to rise above any situation and deliver the best no matter what bbq equipment the circumstances could be. Excellent article!

Jack Mihoff April 5, 2021 10:54 AM


You’re welcome. (I do not work for any company that has anything to do with Faraday Pouches, nor am I being compensated in any way whatsoever for posting this link on this blog).

Raine April 5, 2021 11:19 AM

@Bruce, @Moderator
That post by “Dingi” dated April 5, 2021 10:18 AM seems to be spam

mark April 5, 2021 11:34 AM

It’s clear that I will keep that protocol TURNED OFF. There is no reason for my router to know where I am.

Stasi Wet Dream April 5, 2021 1:18 PM


Apparently this new specification will turn “wireless devices” into sensors. So maybe not just routers but also things like mobile phones?

J. Michael Hudson April 5, 2021 1:26 PM

Anyone who thinks things like this are not already in use, that our homes cannot be remotely imaged in many ways, without oversight, by various police and private spy agencies, is so incredibly naive their opinions on security are of no value, at least to me.
William Binney says as much, and so much has been leaked through other means. There is evidence and xbox can image your room remotely, and given windows 10 uses “telemetry” as the word to describe what it sends back to its hive hq, it is reasonable to assume they consider your PC a drone spy device already.
Since 99% of the world is still using wpa2 and that has no security whatsoever at this point against anyone who tries, most people reading this should admit that they themselves are little more than a drone for their masters.
If you want to read a book on this topic your masters do not want you to see, consider the attached link, and other books of mine you will find at libgen and leanpub.

Paul Suhler April 5, 2021 1:45 PM

Does anyone know which company or companies were the proponents of adding this capability to 802.11?

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Neill April 5, 2021 2:57 PM

802.11bf starts as a RFC, then may be an IEEE standard. This doesn’t make it a Federal nor State law, or a FCC reqd feature. Still up to the buyer to choose a device, and maybe look for alternative Firmware …

Erdem Memisyazici April 5, 2021 4:18 PM

“which means that there probably won’t be any.”

Nooooooo, of course not. Tech industry has the individual’s privacy in the forefront of their considerations. What do you think is going to happen? You don’t think every IoT device as well as the manufacturer and the ISP is going to try to collect that data and sell it as “we know at what time you were in the bathroom” do you? Nah, they’re just going to sell ads.

When is that IoT department going to be made? Will I be alive to see it?

Anonymous April 5, 2021 4:21 PM

Hello.If you learn where the WiFi antenna is, and how long it is, is it possible to send RF at it at just that wavelength so the WiFi antenna will absorb all energy with 100% efficiency and harmlessly melt the solder leads off of itself after a few seconds (depending on wattage/distance/obstructions/etc)?
Or make it automatically increase signal strength gradually until it stops detecting WiFi packets from the device it’s near? Download a big file while doing this, with many packets per microsecond, and wouldn’t the precision be good? It could stop the microsecond one of the solder leads burned off the WiFi antenna, faster than people can blink.Should be safe to the other components in device as long as signal 100% absorbed by WiFi antenna, yes?

lurker April 5, 2021 4:46 PM


Still up to the buyer to choose a device, and maybe look for alternative Firmware …

while the ad writers prepare their copy for the new models “with vitamin-enriched 802.11bf”.

Q April 5, 2021 6:56 PM

@J. Michael Hudson
Anyone who thinks things like this are not already in use, that our homes cannot be remotely imaged in many ways, without oversight, by various police and private spy agencies, is so incredibly naive their opinions on security are of no value, at least to me.

Then why implement this new specification if it now does not provide any new capabilities?

William Binney says as much, and so much has been leaked through other means. There is evidence and xbox can image your room remotely…

evidence? What evidence is there on that?

Just asking.

Anonymous April 6, 2021 5:18 AM

i don’t know if it will work but i have some broken devices to test it on.
this is probably much easier than actually trying to open your phone. probably safer, faster and cheaper, too.

Ergo Sum April 6, 2021 6:10 AM


Also, imagine a world where your neighbours are watching your every move.

They already do, via security cameras, Ring, etc. One cannot walk down the street without half a dozen or so of cameras capturing every steps of the people, vehicles going by, etc. The backyard isn’t a sanctuary either, that’s where the neighbors security cameras do their best. And of course, all of the video surveillance operational 24/7 and connected to the cloud for remote access to the video feed, mainly for the cloud and LEOs.

Indoor isn’t much better via the same technology. People are their own worth enemy, when it comes to security and privacy. They are willing to pay for the technology just to be spied on…

Why would you need the Wi-Fi object sensors? Maybe just to monitor people, who don’t have video surveillance in and around their house…



blockquote>Security and privacy controls are still to be worked out, which means that there probably won’t be any.



Thanks for the laugh, but then I realized just how sad state of technology we live in…

Frank Wilhoit April 6, 2021 6:27 AM

The tragedy of humanity is that we have the intellectual capacity to invent toys (or tools, whether that is a distinction or a euphemism), but absolutely no emotional capacity to process the implications of possessing them or the consequences of using them.

Ismar April 6, 2021 4:48 PM

So what would be the use case for selling this tech to you and me be, I wander? As part of our internet connection- None whatsoever, unless we want to have some perimeter around our dwellings where we can monitor movements but even then I could see it only being useful for people with large areas of private lands , while people in appartments and dense housing would not benefit at all . It is then little more than one of these- make it because we can- cases which will turn out to be more trouble than they are worth.

JonKnowsNothing April 6, 2021 5:13 PM


re:What is the use case for sensors

It will depend on the packaging and some of the abilities are already marketed like heart monitoring and medical telemetry.

It also puts the technology in the “public sphere” which may indicate that the LEAs won’t have to do as much parallel construction. A simpler warrant or FISC warrant (USA) will suffice.

There are two areas LEAs would be interested in, the cell phone aspects which they already have ample access to, but now the WiFi aspect which means they can tap into your Home Network and browse what’s in the Fridge.

The MSM report link below is mostly about a SCOTUS ruling over something that no longer matters (moot), at least it no longer matters for now. Towards the bottom is a reference to Brand X and ” common carrier” status. This marks a potential shift in how the US Courts “may/might” change their rulings in the near future. Much of the internet rides on Brand X/common carrier status. If this were to change, all sorts of interesting things may happen.


ht tps://arstechnica.com/tech-policy/2021/04/clarence-thomas-blasts-section-230-wants-common-carrier-rules-on-twitter/
(url fractured to prevent auto run)

vas pup April 6, 2021 5:49 PM

Greenland votes, split on rare earth metals mining

“The outcome of parliamentary elections could seal the fate of one of the world’s richest uranium and rare earth minerals deposits.

Greenlanders cast their ballots in an early parliamentary election on Tuesday.

The result could decide whether the Kvanefjeld mine project gets the go-ahead in the semiautonomous Danish territory.

The country’s ruling social democratic Siumut and main opposition Inuit Ataqatigiit (IA) parties are split on the issue, Siumut arguing in favor and IA against.
What is the Kvanefjeld mine project?

The project would see a large mining complex built at Kvanefjeld in the south of the island to dig for rare-earth metals, such as uranium and neodymium.

===>These are used in a wide array of sectors and products, including smartphones, wind turbines, microchips, batteries for electric cars and weapons systems.

!!!Estimates show the Kvanefjeld mine could hold the largest deposit of rare-earth metals outside China.

The proposed project is licensed to Australian group Greenland Minerals. ===>Chinese Shenghe Resources is the biggest shareholder.

The rare earth reserves have previously raised international interest by ===>countries hoping to balance out China’s control of 90% of supply worldwide of rare earth metals.

!!!!Given the materials’ importance when making almost any modern military equipment, for instance, China’s domination of the market is seen by some as a national security threat.”

Weather April 6, 2021 6:25 PM

@vas pup
Bull ,they are just the ones dum enough to do it with the current processing steps.

vas pup April 7, 2021 3:50 PM

Greenland: Left-wing Inuit Ataqatigiit party wins election

“The electoral victory is
==>setback for mining companies eager to push ahead with the extraction of rare earth metals under the Arctic island.”

IA’s victory casts doubt over the future of the controversial Kvanefjeld mining complex, which lies towards the southern tip of the Arctic island. ===>Although the party is not completely against mining, they campaigned against a project to dig up rare earth metals from what is one of the world’s largest deposits.

Kvanefjeld — which also contains uranium deposits — is a key source for ==>neodymium, an integral component for wind turbines, electric vehicles, and combat aircraft.”

My nickel: we will see. As Denmark is member of NATO, hands of it could be and would be twisted under pretext of mutual protection to do mining(see usage above). But everywhere around the globe, beneficiaries on natural resources mining are not people – in this case of Greenland (may be Norway is kind of exception) but monopolies. So, when ‘good word’ is not going to work then ‘gun’ will.

vas pup April 7, 2021 4:05 PM

Czech researchers develop revolutionary nuclear heating plant

“A team of scientists has come up with a
==>radical solution to heat cities using spent nuclear rods, which they say is cost-effective and greener than natural gas. As the EU moves away from coal, many are interested.

Researchers at the Czech Technical University in Prague and the University of West Bohemia in Pilsen have come up with an innovative solution: the Teplator, a system which uses the radioactive decay heat produced by spent fuel rods from nuclear reactors to heat water. The team, led by Radek Skoda, has already been granted a patent for the concept and design of what it says is a very cost-effective alternative to coal and gas-powered plants.

Skoda, of the Czech Technical University, told DW that the project was particularly noteworthy because it allows power stations to generate heat from spent fuel elements that otherwise would have to be stored and cooled at great expense for many years.

Skoda explained that the Teplator was similar in size to “mini” nuclear research reactors already operating in major European cities such as Vienna, Prague and Munich but much simpler in terms of technology and design because it “only” generated heat.
===> “The main problem with these small nuclear reactors is that they generate electricity, just like the larger nuclear power plants, and this is very expensive,” he said.

The simplest version of the Teplator has been designed to operate at normal atmospheric pressure and at a temperature of 100 degrees Celsius (212 Fahrenheit), requiring fewer complicated technical solutions and materials.”

My nickel: how many spent nuclear rods do we have in US to utilize or at least do research on this idea utilization?

anon April 8, 2021 12:19 AM

I wonder if Comcast was paid, even partially, to deploy wifi-enabled routers to all of their customers. Its like anti-skynet because its in all of the homes and apartments.

vas pup April 8, 2021 4:59 PM

Facial recognition ID with a twist: Smiles, winks and other facial movements for access

“Like every other human biometric identification system before it (fingerprints, retina scans) there are still significant security flaws in some of the most advanced identity verification technology. Brigham Young University electrical and computer engineering professor D.J. Lee has decided there is a better and more secure way to use your face for restricted access.

==>It’s called Concurrent Two-Factor Identity Verification (C2FIV) and it requires !!!!both one’s facial identity and a specific facial motion to gain access. To set it up, a user faces a camera and records a short 1-2 second video of either a unique facial motion or a lip movement from reading a secret phrase. The video is then input into the device, which extracts facial features and the features of the facial motion, storing them for later ID verification.

====>”The biggest problem we are trying to solve is to make sure the identity verification process is intentional,” said Lee, a professor of electrical and computer engineering at BYU.
!!!!”If someone is unconscious, you can still use their finger to unlock a phone and get access to their device or you can scan their retina. You see this a lot in the movies — think of Ethan Hunt in Mission Impossible even using masks to replicate someone else’s face.”

To get technical, C2FIV relies on an integrated neural network framework to ===>learn facial features and actions concurrently. This framework models dynamic, sequential data like facial motions, where all the frames in a recording have to be considered (unlike a static photo with a figure that can be outlined).

Using this integrated neural network framework, the user’s facial features and movements are embedded and stored on a server or in an embedded device and when they later attempt to gain access, the computer compares the newly generated embedding to the stored one. That user’s ID is verified if the new and stored embeddings match at a certain threshold.

“We’re pretty excited with the technology because it’s pretty unique to add another level of protection that doesn’t cause more trouble for the user,” Lee said.

In their preliminary study, Lee and his Ph.D. student Zheng Sun recorded 8,000 video clips from 50 subjects making facial movements such as blinking, dropping their jaw, smiling or raising their eyebrows as well as many random facial motions to train the neural network. They then created a dataset of positive and negative pairs of facial motions and inputted higher scores for the positive pairs (those that matched). Currently, with the small dataset, ==>the trained neural network verifies identities with over 90% accuracy. They are confident the accuracy can be much higher with a larger dataset and improvements on the network.

Lee, who has filed a patent on the tech already, said the idea is not to compete with Apple or have the application be all about smartphone access. In his opinion, C2FIV has broader application, including accessing restricted areas at a workplace, online banking, ATM use, safe deposit box access or even hotel room entry or keyless entry/access to your vehicle.

“We could build this very tiny device with a camera on it and this device could be deployed easily at so many different locations,” Lee said. “How great would it be to know that even if you lost your car key, no one can steal your vehicle because they don’t know your secret facial action?”

vas pup April 8, 2021 5:20 PM

Unraveling the temporal dynamics of reward signals in music-induced pleasure with TMS:

“Behaviorally, we found that excitation and inhibition of fronto-striatal pathways enhanced and disrupted, respectively, subjective reports of music-induced pleasure and motivation.”

See the whole article (behind the pay wall for more details.

Interesting is that music is not related to basic biological needs – listen to the 7 minutes audio:

Scroll down the page and you’ll find it.

My nickel: everything around is vibration (string theory), so maybe music just do some kind of synchronization of brain parts and that generate pleasure. But, I am NOT neuroscientist.

For security: alertness of security staff by proper selected music, psychological detox of LEOs/IC folks after stressful missions, e.g. suppressing riots.

TRX April 10, 2021 3:59 PM

either a unique facial motion or a lip movement from reading a secret phrase.

So someone hauls out some morphing software, makes some adaptations, puts it on his smartphone, feeds it a picture of the person’s face, and holds the phone up against the camera. The software twists the face image into various expressions and motions.

Likelihood of success: pretty good, I would expect. People are going to mostly use the same subset of simple expressions and motions. Looking like a complete prat every time you unlock your phone is something a lot of people are going to consider.

TRX April 10, 2021 4:03 PM

I have steel siding on my workshop. It’s well within the specified range of my wifi router, but I get zero signal unless I move to a window that can see the house. The 4G cellular phone still works OK, oddly.

Steel siding seems to be out of fashion at the moment, but that and some nice grounded screens over the windows might just be in the home improvement list in the future…

farm co worker April 27, 2021 6:56 PM

I.F. Stone analysis. Our defense strategy is national suicide. We’ve been on the defense too long. We need to find new offenses. You’re On Your Own, you’re not a loan.

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