Rotational motion estimation from ISAR data using frame processing structure

Knowledge of the target rotation rate is a crucial requirement for recovering the cross-range scale of a target image and compensating the image defocusing problem in ISAR imaging. This paper proposes a novel method for estimating the rotation rate of a target from the radar returns based on the frame processing imaging approach. The latter is an alternative ISAR imaging technique to the fast Fourier transform based approaches and target rotation rate is explicitly embedded in the frame processing structure. The method utilizes the intrinsic structures of the frame which spans the Hilbert space of radar return from which the rotational information of target is extracted.