A New Method for ISAR Imaging of Non-cooperative Targets

In the imaging of non-cooperative targets in inverse synthetic aperture radar (ISAR), the migration through range cells (MTRC) and phase error caused by rotation will lead to image blur. To address these challenges, this paper introduces a harmonic wavelet imaging algorithm based on Keystone transform. The algorithm corrects MTRC through Keystone transform and realizes efficient processing of target signals through harmonic wavelet transform, thereby obtaining high-resolution ISAR images. Moreover, this approach circumvents the need for prior target information, streamlines the imaging process, and is well-suited for high-resolution imaging of non-cooperative targets. The method’s effectiveness is confirmed through scattering point simulation data. Experimental results demonstrate that this approach produces clear and well-focused ISAR images even when targets rotate at varying speeds. In comparison to traditional imaging methods, the image contrast achieved by this algorithm is enhanced by 1 to 2 times.