SAR Imaging Method for Moving Targets Based on Omega-k and Fourier Ptychographic Microscopy

The performance of traditional synthetic aperture radar (SAR) imaging methods is limited by the system bandwidth, and the imaging results are easily affected by the target motion state. In the process of SAR imaging, the relative motion between the radar and the target will cause the nonlinear phase error of the echo signal, which makes the imaging quality worse. To solve this problem, we propose a high-resolution moving targets SAR imaging method based on Omega-
$k$
and Fourier ptychographic microscopy (FPM) phase retrieval (PR) technology, which realizes PR by alternating iteration between time domain and 2-D frequency domain. The proposed method is mainly divided into two steps. First, reference function multiply and Stolt mapping are performed to realize echo preprocessing in the 2-D frequency domain, and then, the phase error correction of the compensated echo spectrum is completed by FPM method. Several groups of simulation data and measured data are used for experimental analysis, and the results verify the effectiveness of the proposed method.