Through-the-Multilayered Wall Imaging Using Passive Synthetic Aperture Radar

Most of the existing through-the-wall imaging (TWI) methods using synthetic aperture radar (SAR) tend to apply an active system. In this work, a novel, passive synthetic aperture radar (PSAR), termed TWI-PSAR, was proposed, to focus the image of multi targets behind single/multilayered wall. Incident angle and frequency were considered the parameters that influence TWI image directly. Zero incident angle PSAR, Z-PSAR, was exploited in TWI for enhanced target identification and feature extraction as well as wall effect mitigation. In scenarios where background measurement might not be available or wall parameters were unknown for compensation, Z-PSAR could be adopted. Moreover, to show the effectiveness of the proposed PSAR method in a real situation, sources of opportunity that are relatively wideband aligned in several directions were used to image targets behind the wall. Numerical results showed that PSAR could be an efficient scheme in through-the-wall imaging.