Time-Reversal Processing and Autofocus of Targets Behind Complex Wall

Through-the-wall radar imaging (TWRI) beyond a single wall is a growing area of study [1]. Some previous work was done to mitigate wall effects under little or no knowledge of the wall [2]-[4]. However, past TWRI work has primarily been focused on imaging behind uniform dielectric walls. In this paper, we seek to leverage such effort for complex cinderblock walls commonly used in modern building construction. For walls formed by periodic blocks, much worse frequency-dependent distortion is expected as electromagnetic propagation through wall structures gives rise to Floquet modes. The work in [5] began dealing with this problem for far-field radar scan. In this paper, we focus on integrating electromagnetic propagation models (of the complex wall) with near zone imaging techniques to improve focusing of interior targets.