An ISAR imaging and cross-range scaling method based on phase difference and improved axis rotation transform

Abstract

In this paper, a novel cross-range scaling method for inverse synthetic aperture radar imaging is proposed to estimate rotation angular velocity of the target by fully integrating the energy of all the target scatterers. Firstly, the phase difference is utilized to integrate the scatterers located at a same range cell into one point. Then, the improved axis rotation technique is adopted to transform the energy of all the scatterers into one sharp peak, with the peak position providing the estimation of rotational velocity of the target. Finally, a well-focused and scaled target image can be obtained with the estimated rotational velocity. Compared with the conventional methods, the proposed method can obtain high scaling precision under relatively low signal-to-noise ratio environment since the energy of all target's scatterers can be fully exploited. Both simulation experiment and measured data results are provided to verify the effectiveness of the proposed algorithm.