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Radar That Sees Through Walls Built In Garage

Posted by Soulskill on from the real-life-wall-hacks dept.

szczys writes: Building radar in his garage is nothing new to Greg Charvat. He has a PhD in this stuff and has literally written the book (and a University course) on building your own radar system. This time around it's Phased-Array Radar. This is more than just judging the speed of a baseball or Ferrari. This rig can actually see through walls. Greg uses the example of a soda can to illustrate the quality and resolution possible from this type of system.

37 of 63 comments (clear)

  1. What's so special in walls built in garage? by magi · · Score: 2

    I'm sure you can use various radar-blocking materials to build walls in a garage, not just wood and plastic, but also metal. So what's so special in factory-made ones that they can't be penetrated by this radar? Is it patented? Or a government secret?

    1. Re:What's so special in walls built in garage? by pushing-robot · · Score: 4, Funny

      I think the writer is saying on average people are more likely to build with plywood or drywall in their garage instead of less permissive materials like brick, concrete, or metal.

      So, statistically speaking, a radar system is more effective against walls built in a garage than walls built outside of a garage.

      As usual, the article may provide clarification, but I've found I can avoid the trouble of reading them by simply making wild assumptions.

      --
      How can I believe you when you tell me what I don't want to hear?
    2. Re:What's so special in walls built in garage? by onkelonkel · · Score: 1

      How are the kitchen-built walls different from the garage built walls?

      --
      None of them can see the clouds; The polished wings don't care.
    3. Re:What's so special in walls built in garage? by pastafazou · · Score: 1

      I need some clarification here, and haven't been able to find any references in TFA...do the walls built in the garage, or kitchen for that matter, need to remain in the garage or kitchen? ie are they walls that are installed there, they just need to be made there, but can then be removed and installed elsewhere?

    4. Re:What's so special in walls built in garage? by gstoddart · · Score: 3, Funny

      Temba, his arms wide. ;-)

      --
      Lost at C:>. Found at C.
    5. Re:What's so special in walls built in garage? by Aighearach · · Score: 1

      How are the kitchen-built walls different from the garage built walls?

      Well to start with, the usual construction materials are ginger bread, or (for people that don't have ginger servants on hand) chocolate "bricks."

    6. Re:What's so special in walls built in garage? by Aighearach · · Score: 1

      Depends... did you install 3-phase industrial power in the garage to power the radar? No? Then you'll have to move the installation into the garage, most likely.

      You want to see through walls across the street? I guess you better start buying up used smoke alarms.

    7. Re:What's so special in walls built in garage? by Raistlin77 · · Score: 1

      Shaka, when the walls fell.

    8. Re:What's so special in walls built in garage? by wendyo · · Score: 2

      In TFA, it said he saw "a 12 oz soda can through a 4” thick concrete wall at a stand-off range of 20".

    9. Re:What's so special in walls built in garage? by Talderas · · Score: 1

      I'm glad you asked this question! All walls built within garages are effectively invisible to this radar. If the wall is removed from the garage and installed elsewhere it is still a garage-built wall and continues to remain invisible to the radar system.

      You may be thinking, "What if I take one of these garage-built walls and build a garage out of them?" Let me warn you against this. We've tested this very scenario and it didn't turn out well. Lemons started spontaneously combusting and I think we might have contacted Cthulhu. It's still a little risky at this point but we're pressing on towards the next stage of the project which is creating clothing that is invisible to the radar.

      --
      "Lack of speed can be overcome. In the worst case by patience." --Znork
  2. Now the Little Brother can watch too! by mi · · Score: 2

    Move away, NSA and other Big Brothers — real and wannabes. The Little Brother can watch too now.

    No need for time-travel. "Happy goldfish bowl to you, to me, to everyone"

    --
    In Soviet Washington the swamp drains you.
    1. Re:Now the Little Brother can watch too! by twitnutttt · · Score: 1

      I can't say I'm any happier about the idea of random people being able to peer into a house and see who's home or not anymore than I am enamored of the idea of cops doing it without warrants. I wonder what is a burglar's time-to-break-even for an investment in building one of these?

    2. Re:Now the Little Brother can watch too! by twitnutttt · · Score: 1

      My friend actually was punched without warning while randomly walking down the street, and his nose was broken. And I have studied martial arts. Unrelated facts.
      =)

    3. Re:Now the Little Brother can watch too! by twitnutttt · · Score: 1

      Not sure you are the same A.C. or not?
      Anyhow, you misread my post.
      I simply stated an amusing and, as I said, "unrelated" pair of facts based serendipitously on what the previous respondent happened to write. They bear no relation to the price of rice in China.
      So calm down. =)

      And no in fact, no, years of martial arts preparation should do very little to protect you from a random, unprovoked, and stealthy assailant.

      Nonetheless, since you asked, I think there are other very good reasons however for studying martial arts. May I assume you are not a practitioner? I can tell you that in sports, well-being, and critical reaction-based situations, my martial arts experience has been invaluable to me.

  3. Neat by TheCarp · · Score: 2

    This is exactly the sort of thing i love seeing a project and nice explanation on. This sort of thing will never be my career path, but, is the sort of thing I might play with as a hobby project and I love seeing the areas a person can get into without much formal training expand.

    Of course, I already have a use for such a thing but.... I think it will be easier to use a small drill and a camera to find out if the rumors of my great grandmother's old safe still being in the walls somewhere (plastered over of course) is true.

    Have to imagine that will be cheaper and faster (if not cooler) than building one of these.

    --
    "I opened my eyes, and everything went dark again"
    1. Re:Neat by CanadianMacFan · · Score: 1

      Wouldn't one of those stud finders be easier than drilling a bunch of holes in the wall?

    2. Re:Neat by Ogi_UnixNut · · Score: 2

      Or use a metal detector? Chances are the safe will not be too deep in the wall, and unlike pipes and wires, which would give off short beeps, a safe would register an entire square face to the detector.

    3. Re:Neat by TheCarp · · Score: 1

      Nope stud finders wont even find studs in my house because its old enough to have horse hair plaster, so the studs are covered by horizontal wood slats. SOME stud finders kinda work, most don't work well (admittedly, its been a few years, maybe they got better?)

      Also it wouldn't really identify the object, just that it looked like something more solid was there.

      The reply of metal detector might work better....but there is also a metal chimney pipe for an old gas fireplace that used to be in the room also in the wall, along with possible steam pipes for the single pipe steam heat (as if it wasn't obvious this isn't a new house).

      However.... the rooms on either side of the wall in question have drop ceilings, and there is an odd shape to the wall that makes us think something may have been in there.....but it is entirely possible that bulge in the wall has to do with the installation of the gas fireplace and chimney pipe and not the safe.

      It may be the bulge exists because of the old fireplace and that is why she chose that wall, rather than the other way around.... if it was even in there, this is just kind of an old family memory of the actions of someone who has been dead for maybe half a century (she was gone before I was born, so maybe less but still decades).

      We don't expect there is actually anything in there, but hey it wouldn't be the first time we found something. We actually found an invitation to a "sock hop" in 1911 (at an address which we found is currently a building with a 1920s corner stone) under one of the floors.

      --
      "I opened my eyes, and everything went dark again"
    4. Re:Neat by ChoGGi · · Score: 1

      if you have 50 bucks, http://www.franklinsensors.com...

  4. Re:in the fine print ... by insanecarbonbasedlif · · Score: 2

    Electromagnetic fields and public health: radars and human health, Fact sheet N226

    WHO has also concluded that there is no convincing scientific evidence that exposure to RF shortens the life span of humans, or that RF is an inducer or promoter of cancer.

    --
    Just because I doubt myself does not mean I find your position compelling.
  5. walls that were not built in a garage ? by trevc · · Score: 5, Funny

    Can it also see through walls that were not built in a garage?

  6. Be careful making stuff cheap and easy. by uncqual · · Score: 4, Informative

    In KYLLO v. UNITED STATES , the Supreme Court held in 2001 that:

    Where, as here, the Government uses a device that is not in general public use, to explore details of the home that would previously have been unknowable without physical intrusion, the surveillance is a "search" and is presumptively unreasonable without a warrant.

    in determining that use of a thermal imaging device whose output was used to establish cause for a search warrant was, itself, a search that required a warrant.

    By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own), such devices could move (as planes have) into "general public use" and then be usable by police without a warrant to surveil areas normally off-limits to them without a warrant.

    --
    Why is there an "insightful" mod and why isn't it "-1"? If I wanted insight, I wouldn't be reading /.
    1. Re:Be careful making stuff cheap and easy. by Obfuscant · · Score: 1

      By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own),

      How dare those scum at MIT teach people how to surveil their neighbors and stuff.

    2. Re:Be careful making stuff cheap and easy. by bughunter · · Score: 1

      I doubt a home-built phased array radar will ever be considered "in general public use."

      Besides, these devices only see thru walls built inside a garage, which would generally require a search warrant to see either side of...

      --
      I can see the fnords!
    3. Re:Be careful making stuff cheap and easy. by DRJlaw · · Score: 2

      By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own), such devices could move (as planes have) into "general public use" and then be usable by police without a warrant to surveil areas normally off-limits to them without a warrant.

      I cannot fault your analysis of that particular sentence since I'm certain that some lawyer somewhere will eventually argue that when the "not in general public use" criterion is absent it somehow becomes a "reasonable" search.

      On the other hand, simply because a technology becomes available to monitor something formerly private does not mean that that technology will stay available and become something in "general public use." The now classic evolution-begets-prohibition example is radio frequency scanners. Making or using scanners to listen to analog phone transmissions for fun or profit became a bad idea, not something in general public use.

      If you consider that merely listening to something that people voluntarily broadcast, in the clear, was deemed illegal, what do you think the reaction is going to be to your nosy neighbor bathing your home in artificial radiation for the purpose of peeping at things going on that are not ordinarily visible from the outside? That everyone will accept that shielding their home is impractical and simply shrug? Not once some git uses the technology to surveil a politician it won't.

    4. Re:Be careful making stuff cheap and easy. by Aighearach · · Score: 1

      In KYLLO v. UNITED STATES , the Supreme Court held in 2001 that:

      Where, as here, the Government uses a device that is not in general public use, to explore details of the home that would previously have been unknowable without physical intrusion, the surveillance is a "search" and is presumptively unreasonable without a warrant.

      in determining that use of a thermal imaging device whose output was used to establish cause for a search warrant was, itself, a search that required a warrant.

      By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own), such devices could move (as planes have) into "general public use" and then be usable by police without a warrant to surveil areas normally off-limits to them without a warrant.

      Almost makes it sound like they won't need a search warrant anymore, as long as enough people build these things and put them into general use.

    5. Re:Be careful making stuff cheap and easy. by uncqual · · Score: 1

      I think we are seeing the stage being set for a similar situation with drones.

      If the FAA rules allow private drones to fly at low altitudes over private property without consent of the person controlling the property and the legislators don't pass laws restricting this (the FAA doesn't make rules about privacy - safety is their charter), the expectation of privacy will be reduced as more and more private citizens fly drones at the lower altitudes. Then, police will be free to do so as well and peer into your skylight without a warrant (just as they can look in your windows from the street without a warrant).

      (Of course, they can probably do everything they need to do with a helicopter from a higher altitude and a good camera/lens anyway.)

      --
      Why is there an "insightful" mod and why isn't it "-1"? If I wanted insight, I wouldn't be reading /.
    6. Re:Be careful making stuff cheap and easy. by uncqual · · Score: 1

      When building walls inside your garage is outlawed, only outlaws will...

      --
      Why is there an "insightful" mod and why isn't it "-1"? If I wanted insight, I wouldn't be reading /.
  7. Hmm by koan · · Score: 1

    The same sort of thing has been reduced in size and cost for multirotors, it is not publicly available yet, but try to imagine a consumer drone that can see thru walls.

    --
    "If any question why we died, Tell them because our fathers lied."
  8. Comment removed by account_deleted · · Score: 3, Informative

    Comment removed based on user account deletion

  9. Re:in the fine print ... by bughunter · · Score: 1

    Yes, it can cause ionization by bumping electrons around

    No. Any electrons that can be "bumped" around by EM radiation with wavelengths longer than UV are already in the conduction band. In other words, the ionization already happened and any induced current occurs in "loose" electrons... or, more likely, existing ions in solution.

    It's called non-ionizing radiation for a reason.

    --
    I can see the fnords!
  10. Electronic Countermeasure by presidenteloco · · Score: 1

    Put on your tinfoil hat and turn on your microwave oven.

    CAUTION: do not stick your head in the microwave.

    --

    Where are we going and why are we in a handbasket?
  11. Re:in the fine print ... by kanweg · · Score: 1

    In other news: All researchers collecting scientific evidence that exposure to RF shortens the life span of humans died for unknown reasons before they could finish their research.

    Bert
    Kidding

  12. Re:in the fine print ... by Aighearach · · Score: 1

    Nonsense, burns are well known causes of skin cancer. If your microwave is burning you, that is just as dangerous as the Sun burning you.

    The easy tinfoil-free way to know if the radar is increasing your cancer risk: Does it hurt yet? Burns hurt. Stay safe. If your microwave causes pain, unplug.

  13. Re:360p by Aighearach · · Score: 1

    I know, talk about overkill. What a waste of bandwidth.

  14. Re:Foil-faced insulation by Aighearach · · Score: 1

    Or, if you want to save some money, just wrap the room in chicken wire and aluminum foil.

    Works for hats, too. And you can keep your phablet under the hat when not in use.

  15. Re:in the fine print ... by I'm+New+Around+Here · · Score: 1

    Yes, it can cause ionization by bumping electrons around

    No. Any electrons that can be "bumped" around by EM radiation with wavelengths longer than UV are already in the conduction band. In other words, the ionization already happened and any induced current occurs in "loose" electrons... or, more likely, existing ions in solution.

    It's called non-ionizing radiation for a reason.

    Wait a sec. I thought that was non-unionizing radiation.

    I'm gonna havta rethink my support of that now.

    --
    If you think I voted for Trump because of this post, you're wrong. I voted for Dr. Jill Stein of the Green Party. Again.