A Fast Diffraction Tomography Algorithm for 3-D Through-the-Wall Radar Imaging Using Nonuniform Fast Fourier Transform

This letter proposes the application of the nonuniform fast Fourier transform to the diffraction tomography (DT) image reconstruction method for 3-D through-the-wall radar imaging which leads to a significant speed-up of the image reconstruction procedure. This speed-up is of critical importance in real-time imaging systems since during a long time of imaging, the target displacement may cause errors in detection. Through simulation and experimental examples, the method is validated. In addition, the improved speed of the proposed algorithm is demonstrated by comparing its CPU-time with that of the conventional DT method.