The next step in the technology race may be this:
http://motherboard.vice.com/blog/thi...carry-obsolete
Key quote:
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Basically, Sarabandi and his team used the Doppler radar—which measures an object's speed—to identify the general pattern of a human walking, or what he calls "the DNA of walking." A computer is programmed to recognize that pattern, focusing on the subject's chest, and then polarimetric radar is used to send out a signal at a particular polarization, and analyze the signal that bounces back. An irregular metal object—like a gun—would change the signal.
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So one radar signal identiifes a walking human. The second signal shoots a second beam at the identified person and detects a gun.
Opens up a whole new front in the gun control debate.
Movies theaters, shopping malls, and gas stations can catch you before you even get to the front door and ask you to leave your weapon in your car.