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Wireless Network Modded To See Through Walls 161

KentuckyFC writes "The way radio signals vary in a wireless network can reveal the movement of people behind closed doors, say researchers who have developed a technique called variance-based radio tomographic imaging which processes wireless signals to peer through walls. They've tested the idea with a 34-node wireless network using the IEEE 802.15.4 wireless protocol (the personal area network protocol employed by home automation services such as ZigBee). The researchers say that such a network could be easily distributed by the police or military wanting to determine what's going on inside a building. But such a network, which uses cheap off-the-shelf components, might also be easily deployed by your neighbor or anybody else wanting to monitor movements in your home."
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Wireless Network Modded To See Through Walls

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  • Kids (Score:5, Funny)

    by sopssa ( 1498795 ) * <> on Thursday October 01, 2009 @09:30AM (#29604743) Journal

    wanting to determine what's going on inside a building.

    Now when teens want to sneak out at night, they can easily see thru walls if their parents are sleeping!

    • Re:Kids (Score:5, Funny)

      by tag ( 22464 ) on Thursday October 01, 2009 @09:34AM (#29604793)

      And imagine the teens' surprise and horror when they discover their parents aren't "sleeping" at all...

      • by mcgrew ( 92797 ) *

        Any teenager who doesn't know his parents fuck has led a truly sheltered life. OTOH imagine the parents' surprise when they find that little Suzy isn't alone in her bedroom.

        • by sopssa ( 1498795 ) *

          Yes, everyone knows it. But it's an another thing to actually see it (or even hear it, for that matter)

          • by mcgrew ( 92797 ) *

            What would be worse is seeing mom and stepdad. Even an adult doesn't want to think of his parent having sex with anyone but their other parent.

    • by mantis2009 ( 1557343 ) on Thursday October 01, 2009 @10:00AM (#29605085)
      Investigative reporter Seymour Hersh said that the U.S. military had developed a secret new technology for use in urban warfare. He said the technology was revolutionary, equivalent to the first time tanks were deployed on the battlefield. From what I remember, there was speculation that Hersh had learned that the military could now see through walls.
    • More likely imaging the teens' surprise and horror when their parents spill the beans that RFID+GPS tracking units have been surgically implanted on them by the parents. MUAHWAHAWHAWHAHWHAWH!!!! I can haz your breadcrumb trail.

      Fake hearts that pump continuously, GPS tracking / RFID, indoor thru wall tracking, nanites in the body, controlling computers directly with your brain, van eck phreaking, life-like cgi and hologram, quantum computing, hmmm... sounds like some of those older "sci-fi" books are going t

      • sounds like some of those older "sci-fi" books are going to have to get re-categorized as history books pretty soon.

        Soon? []

    • This is just one more reason to stock up on tin foil.

  • by skornenicholas ( 1360763 ) <skornenicholas@gma i l . c om> on Thursday October 01, 2009 @09:33AM (#29604775) Homepage
    Went straight for the "everyone is spying on me!" ploy a little quick there. Seriously, if anything my neighbors request to see LESS of my movements. This may be due to the fact that I have a clear shower curtain and my bathroom doors lines up to a big bay window facing the road...took me two months to realize that one.
    • by sopssa ( 1498795 ) *

      I have some same kind of experiences too. I live in 16th floor and theres huge window out of the living room. It's a nice view out, but theres other tall building nearly too and you can nicely see inside each other apartments.

      Being the comfortable guy that I am, I do however like to spend my time naked while at home (and while posting to slashdot too). They do not need a device to see me; one of the curtains is broken, so theres nothing I can do about it.

      • They do not need a device to see me; one of the curtains is broken, so theres nothing I can do about it.

        Presuming you rent, take it to management. Hopefully they will care enough to keep the apartment in good condition (I know that's a big if). If you own, get off your duff and fix it, just like you would fix your computer if something went wrong.

        • Although if they own the other tall buildings they might consider the rentability factor after too many people look out their window at the wrong time.

      • Re: (Score:2, Funny)

        by mrsurb ( 1484303 )
        You owe me a new mind's eye, I had to poke it out to get rid of that mental image.
        • Re: (Score:3, Funny)

          by SleazyRidr ( 1563649 )

          The trick is to imagine the poster as a hot 19 year old chick, who refers to herself as a guy because she's a lesbian.

      • spend my time naked while at home (and while posting to slashdot too).

        or worse, while following links in Slashdot... But wouldn't that be as shocking even if you were fully dressed?

      • I thought your place got sold to Ross.
    • Re: (Score:3, Informative)

      by Thaelon ( 250687 )

      What, did you shower with your eyes closed?

      How do you not realize that you can see the road from the shower if people can see in the shower from the road?

  • by TyIzaeL ( 1203354 ) on Thursday October 01, 2009 @09:34AM (#29604795)
    Looks like it is time to get hold of some Aluminum Oxide paint.
    • Re: (Score:3, Informative)

      by pak9rabid ( 1011935 )

      Looks like it is time to get hold of some Aluminum Oxide paint.

      Looks like it is time to start making cell phone calls from outside.

      • by donutz ( 195717 )

        "Looks like it is time to start making cell phone calls from outside."

        Maybe not, if the cell tower is overhead, and you didn't paint the ceilings?

      • You could just VoIP on Wifi, no reason to go outside.
      • Something I don't get is why no one mentioned the option of getting a cell phone repeater (I don't think I saw it in the other article). Block all the signals except the ones you WANT coming in/out of the house. In the case of AM/FM radios most home stereos can be hooked up to an outside antenna pretty easily.

      • Looks like it is time to start making cell phone calls from outside.

        That's right - the bad guys' behind-the-walls vision technology will be completely thwarted.

    • Re: (Score:2, Interesting)

      by giltwist ( 1313107 )

      While a coat of aluminum oxide does count as a Faraday cage, I believe thickness is real issue with the protective power. Paint is only a few molecules thick (relatively) to the more traditional wire mesh. If you were going to build a new house, I think you'd be better including a brass mesh in the walls of your house.

      • Re: (Score:3, Informative)

        by Aging_Newbie ( 16932 )

        Aluminum oxide is a dielectric with breakdown around 16kV/mm and dielectric constant of 9. That puts the material in a class similar to glass. As such it would be among the most ineffective Faraday cages since the walls of such a cage must be conductive, and to be truly effective, VERY Conductive. In fact, at high RF ranges light weight cages and shielding have to be made of silver, gold, etc. to keep the skin effect thickness of the material down to manageable values. What is interesting about the alum

  • by ibsteve2u ( 1184603 ) on Thursday October 01, 2009 @09:35AM (#29604805)

    What with three wireless hubs, an RFID scanner, and half-a-dozen Bluetooth devices always on, I'm pretty sure I'm already casting EMF shadows on my walls.

    Been seeing some really big spiders, too...

  • by carp3_noct3m ( 1185697 ) <slashdot AT warriors-shade DOT net> on Thursday October 01, 2009 @09:36AM (#29604809) []

    Step 1:Paint your house with it.
    Step 2: Install a Faraday cage in the dungeon *ahem* basement.
    Step 3: ??????
    Step 4: Privacy!!!!

    • Step 1 Paint your house with iy.
      Step 2: Install a Faraday cage in the basement.

      Some folks step out into the light and air.

      Which means they'll want WiFi access on the porch, the back yard - the patio and the sundeck.

      • by L4t3r4lu5 ( 1216702 ) on Thursday October 01, 2009 @10:31AM (#29605479)

        Which means they'll want WiFi access on the porch, the back yard - the patio and the sundeck.

        I think you mean the front observation deck, the firing range, and the snipers nest.

      • Don't need to see through walls when your outside... duh!
        • Don't need to see through walls when your outside... duh!

          True. But you might want network access outside without installing an antenna on your roof.

          • WTF?!! Yes... I do alot of surfing while on my roof installing antennaes. LOL.

            Seriously though, the connection goes through windows not covered with aluminum oxide and other holes in your barrier. No house will ever be a complete faraday cage and for something like this, all you have to do is eliminate a large percentage of them to reduce the bounce so as to make the 'shapes' it reports back too vague. In other words... it would be less of a faraday cage and more like 'chafe' to cause interference.
      • I think I know the point you were trying to get at...

        I believe you could paint yourself with aluminium and wear a faraday cage as clothes from when you go outside.
    • I just thought of something... What if the company who developed the paint had this story ready (bribing of researchers) to release right after they announced their paint. Instant interest/sales increase...stroke of genius!

  • I have already seen this being deployed by the Blue Thunder [] helicopter. Way back in the 80s.
    • That was thermal imaging. I distinctly remember seeing Colonel Cochrane (Malcomn McDowell) chatting in a room with a couple of people several floors up, curtains closed with Frank McMurphy (Bruce Schneider) hovering outside in Blue Thunder looking at a false colour thermal image of the room contents.
    • Didn't they also do something like this in the Dark Knight? But I think there was a device inside the structure, not a bunch of them outside, which would make truth more exciting than fiction.
      • Nope.

        Dark Knight used audio. Batman tapped into every phone to be able to turn them all on and hear what was going on... like a BAT does with SONAR....

        Get it?

        Bats? Batman? Sonar?

        • Actually, a sonar works by emitting a sound, and then listening how long it takes for the sound to return when it bounces off an object.

          In the Dark Knight, unless the phones actually emitted some kind of audible noise (or if the phones were capable of producing sound >50Khz, which is probably not the case), it would be incorrect to call them sonars. Instead, they triangulated the sounds coming from the bad guys using multiple phones in order to produce an image, so, while actually much cooler than sona

  • Oh noes! (Score:2, Insightful)

    by onyxruby ( 118189 )
    Horrible, a piece of technology could be abused if used in a certain way by evil and nefarious bad guys. We'll have to ban this wireless technology just in case they're out to get us. Breakout the crowbars, put on the night vision goggles, prep the bolt cutters for backup and defend yourself with the glass cutter before they break in. Tinfoil hats to the rescue!
    • by sopssa ( 1498795 ) *

      Well, this would be quite hard to notice if used for you. Police/Military would probably need to get permission to use it, but that wont stop all the kids and pervert adults.

      • Police/Military would probably need to get permission to use it

        The way they need to get permission to wiretap your phone?

  • by Anonymous Coward on Thursday October 01, 2009 @09:39AM (#29604851)

    Terribly thin floors & cielings mean that I can monitor where my upstairs neighbor is and what he is doing at all times.

    Of course my neighbors can monitor when I have sex and how good it is, but I kind of get off on that anyway...

    • "Of course my neighbors can monitor when I have sex and how good it is,"

      Those IBM Model Ms ARE rather loud...

  • The Dark Knight (Score:3, Informative)

    by GameboyRMH ( 1153867 ) <> on Thursday October 01, 2009 @09:42AM (#29604895) Journal
    Didn't Batman have some goggles that work like this in The Dark Knight?
    • I was going to say Batman did it first.. although he used cell phones.... all of them (at least in Gotham)
  • by devnullkac ( 223246 ) on Thursday October 01, 2009 @09:42AM (#29604909) Homepage

    This sounds like a job for... Aluminum Oxide Paint! []

  • I see The Dark Knight movie had it wrong!
  • The only picture in TFA was a blob.

    Get back to me when it can see tits....

  • Personally, I think I'll set up a Van DeGraff generator. Really adds to the mad scientist lair effect too.

  • they can really prosecute people for sodomy.
  • Neighbors (Score:3, Funny)

    by Anonymous Coward on Thursday October 01, 2009 @10:03AM (#29605129)

    Up, down, up, down, what the heck are they doing?

  • the architect who designed my home put a floor to ceiling window RIGHT NEXT TO THE TOILET. I applied privacy film to the glass, and keep the shade down, and the lights off... no, I'm not worried about my neighbors using wifi to monitor my movements...

    • Wow, I'm surprised you didn't notice that before you had the plans built... (or do you mean the architect who designed your model?)

  • by Lord Lode ( 1290856 ) on Thursday October 01, 2009 @10:12AM (#29605235)
    It's called a window.
  • This [] should solve any peeping Tom/Big Bro Cop issues we have. Get out your paintbrush, ladder, and overalls...

  • Google Maps? (Score:3, Informative)

    by Zantac69 ( 1331461 ) on Thursday October 01, 2009 @10:20AM (#29605317) Journal
    This cracked me up:

    "We envision a building imaging scenario similar to the following. Emergency responders, military forces, or police arrive at a scene where entry into a building is potentially dangerous. ... The nodes immediately form a network and self-localize, perhaps using information about the size and shape of the building from a database (eg Google maps) and some known-location coordinates (eg using GPS).

    Anyone remember []?

    Oops! Map was wrong and we are in the wrong house!

    • Oops! Map was wrong and we are in the wrong house!

      The occupants and first responders are still at far less risk than if the entry was made blindly.

  • by drinkypoo ( 153816 ) <> on Thursday October 01, 2009 @10:22AM (#29605361) Homepage Journal

    You can get xbee-equipped computers (mostly with pics, avrs, basic stamps, etc) for super cheap, like three for a bill. I'm considering them for a remote monitoring and control application where wifi is overkill in some ways and inadequate in others (line of sight issues.) Current xbee modules all seem to support mesh networking, which is really the big draw to me of the protocol itself here, or at least the most readily available implementation. Being able to put out a sensor net and get a sort of meta-sense out of it would be all the more exciting. I'm sure the same thought has occurred to everyone, of course. This seems like the kind of thing that would give the [para]military types a massive hard-on given that they're already playing with the idea of gigantic numbers of drones and communications devices scattered across the battlefields of tomorrow... and our homes and cities.

  • Too cumbersome. (Score:3, Interesting)

    by AniVisual ( 1373773 ) on Thursday October 01, 2009 @10:39AM (#29605623)

    by "interrogating" this volume of space with many signals, picked up by multiple receivers, it is possible to build up a picture of the movement within it.

    As I understand, the researchers used 34 receivers. You will need a whole lot of receivers. More than you might want to buy and maintain to offer you what is at best a poor resolution of moving things beyond walls.

    • by Firehed ( 942385 )

      No kidding. I'm a lot less likely to notice a cleverly-placed webcam than three dozen new WiFi APs.

  • Wow innovation! (Score:3, Insightful)

    by rahlquist ( 558509 ) on Thursday October 01, 2009 @10:55AM (#29605889) Homepage

    Discerning the physical location and movement of an object with radio waves, what can we call such a thing?

    Ahh, yes, Radar...

  • Competition (Score:3, Informative)

    by lbgator ( 1208974 ) <> on Thursday October 01, 2009 @11:15AM (#29606215)

    Although this thing idea is neat, there is an Israeli company that is currently selling RF tech to do the same thing. It comes in a package the size of a suitcase, and can be deployed without having to put transmitters/receivers all over the place. Check it out.

    I actually applied to work for that company but wasn't smart enough. Blasted Israelis and their blasted smarter-than-me-ness.

  • by mckinnsb ( 984522 ) on Thursday October 01, 2009 @11:18AM (#29606269)
    The image in the article isn't really good. If you want to see a demonstration of what they did in real time, it's here [].
  • by boristdog ( 133725 ) on Thursday October 01, 2009 @11:27AM (#29606383)

    Another advantage of living in the country.

    If someone is within 1 km of my house (and I doubt this system has that kind of range) the dogs and various livestock alert me WAY before that person can see my movements. And those movements will be important to that person at this point. Especially the "cocking the shotgun" movement.

  • by shadow_slicer ( 607649 ) on Thursday October 01, 2009 @11:30AM (#29606419)

    Check out their demonstration videos at [].

    I was fortunate enough to see the demo at Mobicom last year. It's a really neat application, even if the math is nothing new.

  • by TheHawke ( 237817 ) <> on Thursday October 01, 2009 @11:45AM (#29606635)

    They just reinvented RADAR for pity's sake! What is 802.xx? 2-5GHZ Microwave frequencies! It's rather like reinventing the wheel, only this time they used millimeter band, low powered microwaves to do it with. Hooray they are able to use it as a poor man's license-free RADAR system, I'll give them credit for that.

  • by cpu_fusion ( 705735 ) on Thursday October 01, 2009 @12:00PM (#29606849)

    ... wherein the Supreme Court (including Scalia, amazingly) held that peering into homes using equipment that was not available in common use by the layperson was within the bounds of the 4th amendment, and therefore requires a search warrant.

  • If anybody sneezes my laptop notifies me by disconnecting form the network.

  • Whew! Imagine the fun the neighbours could have watching which room you're in: "They're watching TV, they're watching TV, they've put the the kettle on, they're watching TV...." I'm sure it will be worth the effort of setting up 32 receivers and a suitable transmitter and calibrating it - all so the neighbours can work out which room I'm in. The winter evenings are going to just fly by.....
  • 'But' (Score:2, Interesting)

    by dugeen ( 1224138 )
    Interesting implication that, while your neighbours shouldn't be monitoring what you're doing inside your own house, it's perfectly acceptable for the police and the army to be watching you in this way.

Research is what I'm doing when I don't know what I'm doing. -- Wernher von Braun