Novel ISAR Range Alignment via Minimizing the Entropy of the Sum Range Profile

A novel global range alignment technique for inverse synthetic aperture radar (ISAR) imaging is presented in this paper. Instead of requiring the parametric model for the relative offset amongst the range profiles, the alignment is investigated from the viewpoint of optimization, where the minimization of the entropy of the sum range profile (SRP) is employed as the optimization criterion. The precise range alignment within a range cell can be achieved by implementing the proposed algorithm. With respect to the existing global method, the proposed one does not require any interpolation operation and multidimensional search operation. Experimental results based on real measured data of maritime non-cooperative target validate the effectiveness and the efficiency of the proposed algorithm.