Rough Surface Estimation for Subsurface Imaging

In this paper a distance measurement based reflection point terrain estimation method (RPTEM) for characterizing two-dimensional (2-D) rough surfaces is presented. The method is based on the analysis of timedomain field data obtained by GPR system with Synthetic Aperture Radar (SAR) scan over 2-D rough ground surfaces. The distance from each antenna position to the ground surface is established from the late time responses of each antenna. The distance information extracted form the reflected signal is used to to create an estimate of the rough ground. A circle is considered with a corresponding radius, which is the distance information, with the antenna location at its center. An outline of the terrain is obtained through the overlapping circles at neighboring antennas. The terrain profiles obtained via both SAR-processing and the RPTEM are discussed and compared with the actual geometry. The results show good agreement between the imagery of the surface height distribution obtained by RPTEM, SAR processing and the actual geometry of the 2-D rough surfaces. Time consumed for image reconstruction is discussed for each method.