Bi-static high resolution imaging for ship targets with sparse apertures and its application in InISAR

In this letter, we focus on the high-resolution imaging of ship targets under sparse aperture condition and its application in three-dimensional (3D) imaging. A bi-static high-resolution algorithm dealing with the sparse echo condition is proposed, which consists of the following processing steps: (1) A side-lobe apodization–multiple orthogonal least-square method is proposed to recover the complete signal and reduce the influence of side-lobe at the same time, which enhances the precision of phase extraction in interferometric inverse synthetic aperture radar (InISAR) imaging; (2) The bi-static configuration is used to accentuate the relative motion between the target and radar, such that the requirement for long coherence processing time can be avoided and (3) The 3D InISAR technique is employed to obtain the 3D images of the ship targets. Experiments with simulated and real data are utilized to demonstrate the effectiveness of the proposed method.