MIT Develops New Radar Technology: Military Could See Through Walls

The ability to see through walls is no longer the stuff of science fiction. Thanks to new radar technology developed at MIT's Lincoln Laboratory a system has been built by researchers that can see through walls from some distance away, giving an instantaneous picture of the activity on the other side. The Massachusetts Institute of Technology's Lincoln Laboratory has presented new radar technology that would allow humans to see through a solid wall. The device is 8½ feet long. It consists of an array of antennae arranged in two rows -- including eight signal receiving elements on the top and 13 signal transmitting elements at the bottom.
Other components include cabling, a low-power radar transmitter, a sensitive radar receiver, a filoscope (used as a small screen purely for diagnosing problems) and of course a larger screen, similar to the average 24 inch computer screen, where one can actually view images transmitted. All this equipment is mounted onto a movable cart that can stand at a range from 15 to 40 feet from the location you're observing. Researcher and leader of the project, Dr. Gregory Charvat, tells the technology was conceived with the notion that it would be used by U.S. soliders during war time. "It can be powerful during military operations especially in urban combat situations," said Charvat.
The device works by emitting frequency waves at a low-power microwave signal. That signal will hit in the direction of the target, in this case a wall. Each time a wave hits the wall only some of it is absorbed inside of the wall, a tiny portion actually gets through. Once the waves go through the wall, they propagate whatever is behind the wall and pass back through that wall and into the radar's receivers. Only moving images can be detected, so an image such as a couch or nonmoving appliance would not show up on the monitor. Images appear as red blobs moving about the screen and it looks as the image would be away and across from the actual radar. The researchers are currently working on a detection algorithm that would convert these red blobs into a cleaner image. "We'd like to have it so that you can see either small crosses or maybe squares," said Charvat. Charvet tells  that the concept of humans being able to see through a wall was initially his dissertation at Michigan State University. He says he worked with an adviser and built a small mechanical version of the MIT radar system – with the use of a high precision motor from a garage opener - however that model took 20 minutes just to look through a four inch concrete wall. Later he worked out of his garage while he developed an 8½ foot long, phased array model of the device, but this one took 2 seconds to go through the wall and as a result produced one image every two seconds. Charvet said this was simply not feasible. Finally after partnering up with fellow colleagues Tyler Ralston and MIT Lincoln Laboratory associate John Peabody, they developed this model. The trio combined their areas of expertise, applied for a grant, and began their work on developing this new system that can produce images in real time. Charvet says they've created this prototype with the idea of it being for military use. Their vision is for soldiers to mount the device inside of a vehicle and use that as a sort of command center. The vehicle would then be parked around the corner or across the street from the target.