Through-the-Wall Small Weapon Detection Based on Polarimetric Radar Techniques

摘要

In this report, we investigate techniques for small weapon detection in the context of sensing-through-walls radar sensors. Our approach exploits the radar wave polarization in order to discriminate between a human carrying a weapon and an unarmed human. We first develop a polarization optimization procedure for a rifle-like target, but demonstrate that this technique does not perform as expected in the presence of a human. Next, we introduce a more robust discrimination procedure based on the ratio of the cross- to co- polarization radar signature. We show that this technique produces a measurable enhancement (of at least 8 dB) when the human carries a weapon versus the case of an unarmed human. We support this idea with numerical examples that include radar cross section evaluations, synthetic aperture radar images of humans in rooms of various complexities, and the Doppler spectrum of a moving human.