Ground Moving Target Indication via Coprime Array MIMO 2-D-VSAR Joint EGO-DPCA Filter

The velocity synthetic aperture radar (VSAR) algorithm is a method used for slow ground-moving target indication (GMTI) and parameter estimation based on array processing. However, this method is limited by an expensive computational burden and is disabled for detecting fast-moving targets. This article uses a coprime array configuration with smaller element spacing to improve the unambiguous range velocity estimation. This improvement results in the detection of fast-moving targets. Additionally, we propose an improved coprime VSAR algorithm that uses azimuth time shift instead of two-step phase compensation in every pixel of channel images to decrease the computational burden. However, the weak and slow-moving targets are not detected using the coprime VSAR method. Thus, we introduce a filter called the extended greatest of displacement phase center antenna (EGO-DPCA) to detect weak and slow-moving targets. Furthermore, the proposed algorithm is extended to the coprime 2-D VSAR to estimate the azimuth direction velocity of moving targets neglected in the conventional VSAR algorithm. Therefore, the azimuth resolution of moving target imaging significantly increases by estimating the azimuth direction velocity. Since all processes are performed in the detected pixel of moving targets, the complexity and computational burden are significantly reduced.