See Through WallsBy: Willie D. Jones
Portable radar devices see through walls and report what's inside
Through-the-wall radar devices that are lightweight, portable, and able to focus up to 20 or 30 meters ahead are available to municipalities and law enforcement agencies. Two such devices are RadarVision, built by Time Domain Corp., of Huntsville, Ala., and the Prism 100, from Cambridge Consultants Ltd., in Cambridge, England. Both rely on ultrawideband, a fairly new technology known mainly as a promising high-speed, low-power radio communications transmission technique.
Both devices can detect the presence of inanimate objects through the wall, but only motion (in the form of a moving blob of color on their built-in color screens) is shown to the user. The devices are so sensitive that even if someone on the other side of the wall is sitting still, the machines can detect the rise and fall of the person's chest with each breath.
What the user sees is a plain view of what lies on the other side of the wall, but seen onscreen from above. An optional mode shows the space on the other side of the wall the way it would appear from the side.
No Place to Hide