Image auto-focusing with multi-layer non-homogeneous wall in through-wall-radar imaging

In the practical application of through-wall-radar imaging, the confronted wall is generally multi-layer and non-homogeneous, which defocuses the target image and displace target away from its true location. Therefore, the algorithm of image auto-focusing with the multi-layer and non-homogeneous wall is proposed in this paper. With respect to multiple array echoes, one best focusing time-delay is searched in the assumed range to approximately compensate the different propagation time-delays from the anomalous propagations in wall. The searching of one focusing time-delay substituting for multiple focusing time-delays can effectively reduce the computation burden to implement real-time imaging. The experiment results demonstrate that the proposed auto-focusing algorithm can implement the high-quality target image with the fine focusing degrees and the minor target displacement.