Concealed object contrast enhancement using radar methods in a submillimeter-wave active imager

A single-pixel, active, heterodyne submillimeter-wave imager has been developed to detect concealed weapons on persons at standoff ranges of many meters. A major imaging challenge is that a targetpsilas reflected power often yields poor contrast of concealed objects because of specular scattering. To address this problem we have adapted high-resolution radar techniques to a 600 GHz active imager and generated three-dimensional through-clothes images of concealed objects with cm-scale resolution.