Three-Dimensional InISAR Imaging of Maneuvering Targets With Joint Motion Compensation and Azimuth Scaling Under Single Baseline Configuration

The $L$ -type double baseline configuration (three antennas) radar system is commonly adopted to obtain 3-D images in the traditional interferometric inverse synthetic aperture radar (InISAR) imaging, making high demands on the complexity of hardware design and signal processing. In this letter, a novel InISAR imaging framework based on single baseline configuration (SBC) (two antennas) for maneuvering targets is proposed, which can acquire the range and azimuth coordinates of the targets through transmitting wideband signals and azimuth scaling. To address the problems of error transmission and insufficient robustness in the traditional cascaded motion compensation method, a joint motion compensation and azimuth scaling (JMCAS) algorithm is developed. By maximizing the image contrast (IC), this method can perform the optimal parameter estimation of translational and rotational motion of maneuvering targets, so as to simultaneously achieve the fine motion compensation and azimuth scaling. In addition, a non-coherent fusion image registration (NCFIR) algorithm is presented to achieve the image registration between the two antennas in a vertical direction. On this basis, the height coordinates of the targets can be obtained by means of interferometric processing. Extensive experimental results from both simulated and real data corroborate that the proposed algorithm can achieve high-precision 3-D imaging of maneuvering targets with low hardware complexity at a low cost.