Computationally Efficient Time-Varying Isar Imaging

By exploiting the relative motion between the target and the radar, high-resolution images of moving targets can be produced using inverse synthetic aperture radar (ISAR). Recent studies have shown that accurate ISAR images can be obtained using the non-parametric high-resolution Capon and APES spectral estimators. In this paper, we propose a computationally efficient time-updating of the two-dimensional (2-D) Capon and APES spectral estimators using their inherent time-varying displacement structures. Numerical simulations indicate that the proposed implementation offers a significant reduction in computational complexity as compared to other recent implementations