A novel range alignment method for ISAR imaging

In the Inverse Synthetic Aperture Radar (ISAR) imaging process, the range alignment is the base of motion compensation and image reconstruction. The time difference between two consecutive radar echoes is very small, so the envelopes of two consecutive range images we get from two consecutive radar echoes are nearly the same. When two consecutive range images are aligned, their envelopes have the smallest difference, thus, the sum of squares of differences of corresponding range units of two consecutive range images is the least. Base on this theory, a new method of range alignment is proposed in this paper, which is called as the least variance method. The comparison between the least variance method and the minimum entropy method on the simulated and measured data processing demonstrates the effectiveness and superiority of the new method proposed in this paper.