William Fox of the Naval Postgraduate School in Monterey and John Vesecky, his colleague at UC Santa Cruz, are working on a modified radar gun
that can identify suicide bombs worn under the clothing. To do this, they cataloged the most common arrangements of looped wires used to construct "suicide vests," and developed software that can identify the radar cross-section of each. So far, results have been pretty good: according to New Scientist
, "telltale factors in the polarisation of the reflected signals" allowed them to correctly identify volunteers dressed as bombers up to ten meters away, roughly eighty-five percent of the time. Of course, even with a success rate this high, such a system would be prone to kicking up false positives. In order to minimize this, the devices would have to combined with other technologies, such as smart surveillance camera systems and infrared imaging.