A fast imaging algorithm for UWB through-wall radar

The Ultra-WideBand Through-Wall Radar (UWB TWR) has become a keen research topic in recent years because of the urgent needs of counter-terrorism and calamity rescue, etc. Conventional UWB imaging algorithm can not meet the demand in the capability of targets recognition and calculation efficiency. The Shape Estimation Algorithm based on the Boundary scattering transform and Extraction of Directly scattered waves (SEABED) can be used to reconstruct target shape, but it is restricted by the presence of the wall in the application of TWR. In this paper, a novel envelop curve algorithm is presented to adapt to the special conditions in TWR. To realize imaging of the target boundary, the algorithm extracts the quasi wavefront from the received signals and computes the envelop curve of a group of circles. FDTD numerical simulations validate that the algorithm can be used to obtain two-dimensional images of targets behind walls. The position error by the influence of the walls is also analyzed.