Frequency Extrapolation and Scaling Transformation-Based ISAR Imaging Method

This study presents an innovative Inverse Synthetic Aperture Radar (ISAR) imaging method based on frequency extrapolation and scaling transformation techniques. Initially, ISAR images of small-scale ships (1.15 meters in length, 0.14 meters in width) are simulated within the 8-12 GHz frequency range, generating the corresponding data. Then, the frequency extrapolation technique is used to extend these data to a broader frequency range (8-20 GHz), resulting in a second set of ISAR images. Through scaling transformation, the extrapolated high-frequency data are compared with the simulated ISAR images of large-scale ships (11.5 meters in length, 1.4 meters in width) within the 800-1200 MHz frequency range, demonstrating their similarity. This method addresses the challenges of ISAR imaging for electrically large targets, which typically require wide bandwidths and high sampling points. By compensating for these requirements, the proposed approach reduces the dependency on simulation software, improves efficiency, and provides a new solution for target identification under frequency constraints.