An Effective Translational Motion Compensation Approach for High-Resolution ISAR Imaging With Time-Varying Amplitude.

The performance of traditional translational motion compensation methods is degraded when migration through range cell (MTRC) occurs or the echo amplitude is time-varying. In this letter, an effective translational motion compensation approach is proposed for high-resolution inverse synthetic aperture radar (ISAR) imaging with time-varying amplitude. The proposed algorithm based on the minimum mean square error (MMSE) criterion and the energy extraction of prominent points can realize the translational motion compensation accurately. First, the observation time is divided into multiple subapertures, and the range alignment of the echoes within each subaperture is achieved. Then, the range alignment between subapertures is realized based on the MMSE criterion. The Radon transform is performed on the range-aligned echoes to extract the prominent point with the maximum energy, and the envelope's fine alignment and phase correction are realized. After rotation compensation, a well-focused ISAR image is obtained. Simulation experiments and real measured data demonstrate the effectiveness of the proposed algorithm.