3-D reconstruction, azimuth prefocusing, cylindrical symmetry, elevation synthetic aperture, Ocean engineering, TC1501-1800, Geophysics. Cosmic physics, QC801-809

Unlike the traditional multichannel synthetic aperture radar (SAR) 3-D reconstruction technology, the single-channel SAR with two synthetic apertures in the vertical and horizontal planes, realized by curved trajectory, has the advantages of requiring less acquisition data, lower device cost, and fewer limitations on trajectories. However, due to the complex aerodynamic configuration and flight characteristics, critical challenges are faced, including the mathematical model establishment, signal property analyses, and reconstruction approach design. In this article, to address these issues, a 3-D vector geometry model of the curvilinear SAR (CLSAR) system is presented and its properties, including elevation bandwidth and resolution, are studied in detail. Then, a novel 3-D reconstruction approach for a single-channel CLSAR system based on azimuth prefocusing is presented, in which the cylindrical symmetry of the SAR system is utilized to provide accurate azimuth information of targets in observing scenes. With the assisted azimuths, the scene imaged in the vertical plane can be performed, and the 3-D reconstruction of interested targets can be obtained. Numerical results using simulated data demonstrate the effectiveness of the proposed approach.