Mid-Range Two-Dimensional Fast Imaging in Pseudopolar Coordinate Format for Wideband Array

The letter proposes a wideband millimeter wave imaging algorithm in the mid-range (Fresnel region) and provides detailed derivations. The method corrects the bulk range cell migration separately in each subareas, and performs the image processing in the pseudopolar coordinate system. The proposed method is capable of directly processing echo signals in the spatial-frequency domain for sparse multiple-input–multiple-output array, thereby reducing data size and computation load. Moreover, it offers superior image quality for large scenes. Validation is conducted through three-dimensional experiments.