Polarimetric UWB SAR for subsurface imaging of building structures

Full polarimetric near-range UWB radar measurements for nondestructive high-resolution subsurface imaging of building structures are presented. We use a stepped frequency continuous wave GB-SAR system based on a 4-port VNA in combination with an antenna array consisting of four linearly polarized Vivaldi antenna elements. Coherent quad polarization data is acquired in an ultra-wideband frequency range from 1 GHz to 20 GHz. Results obtained from 2-dimensional scans of various targets demonstrate that the SAR processed high-resolution subsurface images are suitable to detect cracks and deformations of internal structures including metal nails and bolts. PolSAR analysis for measurements of different canonical scattering targets give promising preliminary results of polarimetric signatures.