Video: MIT's X-Ray Vision System Can See Straight Through Concrete Walls

By Clay Dillow Posted 10.18.2011 at 2:15 pm 12 Comments

Lincoln Labs' Radar System Sees Through Walls

The ongoing imperative to turn soldiers into “supersoldiers” has seen some pretty superhero-esque technological enhancements become real-world defense sector pursuits, like the ability to hear through walls, to fly at will, or to harness superhuman strength. Now we can add X-ray vision to that list.

A team of researchers at MIT’s Lincoln Lab have created a radar array that provides a realtime picture of what’s happening on the other side of solid concrete walls, even when they’re eight inches thick and 60 feet away. That’s no simple feat. More than 99 percent of radar signal is lost passing through the wall--and another 99 percent is lost as the reflected signal passes back through. But by leveraging signal amplifiers, a clever filtering technique, and some powerful digital processing, the new radar system is able to produce what basically amounts to a realtime video of movements on the other side of a solid wall at 10.8 frames per second.

The array consists of two rows of radar antennas--a top row of eight transmitters and a bottom row of 13 receivers--with the transmitter row augmented with powerful signal amplifiers to offset the signal loss caused (twice) by the wall. The transmitters fire strengthened S-band waves at the obstacle, and here the system meets its first real challenge: the wall itself.

Regardless of how strong the waves are or how much wall they can penetrate, the wall will always show up as the brightest element. To circumvent this issue, the system employs an analog crystal filter that can be used to delete the wall from the results. That’s because the wall, at say 30 feet away, will return signals at a different frequency than the people on the other side of the wall, which are perhaps 35 or forty feet away. The system establishes where the wall is and filters out those signals, leaving behind only the frequencies that correspond to distances beyond the wall.

It also filters out inanimate objects, because the system works based on motion--that is, on comparing each frame to the previous one and seeing what’s changed. So furniture and other obstructions won’t show up in the final results, but humans--even humans trying their best to remain motionless--will register.

The end result is an image that offers an overhead view of the area on the other side of the wall. The system is pretty rough as it stands currently. The array is about 8.5 feet long (not man portable) and even after all the algorithmic processing the system performs on the receiving end, targets on the other side of the wall are crudely represented by red blobs slowly moving on the screen.

But given some tweaking--the team wants to work on the end-user interface so the imagery is sharper and targets are represented as crosses or squares rather than l like storm systems moving on a weather map--and perhaps some shrinking, a vehicle-mounted version of this could seriously augment situational awareness during urban combat. The Lincoln Lab team offers a much more detailed explanation of the nuts and bolts in the video below.

[MIT News]

Previous Article: Video: The Motion-Sensing Banking App We've All Been Waiting For

Next Article: The World's Most Complete, High-Res Topographic Map Gets an Update

12 Comments

Link to this comment

ThisNameTaken

10/18/11 at 2:38 pm

Almightily police state on its way! See through walls, drones circling political protests taking biometrics on every single protestor. RFID chips, err, iPods in every pockets.... All communications monitored, cameras on every street corner.... political propaganda required reading.... "Anti-American" Salem witch trials in the name of "terror."

*Hears the Imperial March in the background*

Or shall we go Demolition Man.... BEEERRRRR, you are fined 1 credit for a violation of language laws. BERRRRR, you are fined 15 credits for a violation of the anti-free speech laws.... BERRRRRR you are fined 1000000 credits for contraband literature known as 1984....

Link to this comment

rosen380

10/18/11 at 5:40 pm

"Uh...and if we are detecting neutrinos already, how long before we can use them instead of xrays? Neutrino beams will change everything if we can get sensitive enough detectors."

Problem #1: This thing is already pretty big-- have you seen the size of the neutrino detectors? They are truly massive objects.

Problem #2: Detectors only pick up a couple of neutrinos for trillions that are emitted. They hardly interact with matter, so you also need a real lot of them. You would only pick up the neutrinos that happen to make it through the wall both ways, but not through the objects beyond the wall [otherwise you get nothing to detect.

Problem #2a: shrink something like the LHC, to a millionth of it's size without affecting its' performance.

Problem #2b: It has gotta run a fraction of a percent of the power that the LHC does...

--
One question about the tech- if I know what frequencies they are using, woudl anything stop me from creating a device that sends them out and surround my building with them?

Link to this comment

Distantstar

10/18/11 at 6:23 pm

That's some serious signal loss.Need to put more watts into that transmitter.

Link to this comment

10/18/11 at 6:34 pm

It is big box baby science. The images are to blurry to be of use and how would it look with a room full of furniture too. Still, I am not knocking these guys.

I am very interest how this develops in the future. I think it is very cool new radar science!

Link to this comment

inaka_rob

10/18/11 at 9:55 pm

@rosen380 its really not that crazy. Look at the first computer. It weighed 4 tons and took up a building. Now I have a dual core cpu in my POCKET!!!! and the first 8 core cpu just his the market!!! its really not that crazy to think they can shrink neutrino detectors down.

@D13 +1

Link to this comment

drchuck1

10/19/11 at 6:57 am

@Q...read the article, inanimate objects are deleted and who can't differentiate between squares and x's and @D13 neutrinos don't reflect back to a reciever, cheers

Link to this comment

Grunt

10/19/11 at 7:52 am

drchuck1,
I understand this is a prototype and I am impressed with it. I am very much interested in how this grows in ability. I did not mean to indicate anything bad on prior comments. This is great new technology!

Link to this comment

cosmic

10/19/11 at 8:40 am

So coming to our local gadge store very soon: " X-Ray glasses ". Their finally here.

Link to this comment

Volt

10/19/11 at 10:48 am

If you wanted a more sensitive neutrino detector, your best bet would be neutronium. What's that? You don't have a neutron star that you can mine? Guess you'll have to stick with normal density matter that has atoms that only have about 2.26 E^-8 percent of their volume that actually is sensitive to neutrinos. I'm not saying it can't be done, but heh... Good luck...

Oh, and by the way, X-Rays and microwave radio waves are on opposite ends of the spectrum. X-Rays would just hit the wall and stop because of their shorter wavelengths. It's because of the longer wavelengths that the signals even get through at all. I mean, you are only picking up .0036% of what you put out. The fact that they can detect that is astounding to me and I am quite pleased with such things. This certainly has a long way to go before it can be used in a warzone, but I definitely think this is a great start to some new tech that'll definitely see action some day.

My hat goes off twice to these guys. Once for doing something to help our soldiers survive to fight another day and twice for making something that has a superpower.

Link to this comment

microwaveskillingme

12/20/11 at 3:09 pm

HELP ! You guys at MIT are obviously into dealing with Micro waves. You must have safety protocols in place to help you stay safe while dealing with these signals ? I am living in a town that has way too many cell tower transmitters & WiFi units around. My house is surrounded by over 50 transmitters & dozen of neighbor wifi units. I am suffering with massive & very painful headaches from constant bombardment of microwaves. My bedroom has readings as high as 1700 uW/m2 for 24 hours a day.. I will not last long at this rate.
Is there any practical way to protect myself from micro waves ? Is there a way to collect or deflect the signals so that they do not enter my living space or to block them from me personally ?
Can you put me in touch with an intelligent doctors or other professionals that can diagnose & treat people like me who are suffering from microwave exposure ?

Any info or help would be appreciated. Contact me @ rschranz@hotmail.com

Popular Tags

Technology

All Tags All Photos All Videos

Technology

+ More Photo Galleries

June 2013: American Energy Independence

Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.