Motion compensation for ISAR based on the shift-and-convolution algorithm

Abstract

ISAR (Inverse Synthetic Aperture Radar) is a coherent technique that obtains images of targets by processing the echoes returned during the dwell time. A higher angular resolution than the antenna beamwidth may be obtained. In this paper we report high resolution ISAR images, which have been obtained from data captured by a millimeter-wave LFMCW (Linear Frequency Modulated Continuous Wave) radar. The target translational motion compensation is achieved by means of a new parametric algorithm, which makes use of the shift- and-convolution technique. This image autofocusing algorithm is compared with Prominent Point Processing (PPP) and Phase Gradient Autofocus (PGA). Simulated and real data from the millimeter-wave LFMCW radar are used to verify the proposed technique, although the method is also applicable to any kind of coherent radar.