Système de mesure du Doppler différentiel sur raies fluctuantes

Abstract
In order to use differential Doppler (D.D) in target motion analysis, we present a measurement system providing accurate D.D estimation when the primary frequency lines are linearly modulated. Such low frequency variation, generally due to source motion, is frequently perturbating classical high resolution measurement techniques on real signals (Time delay-Doppler ambiguity, acceleration,..). The proposed system provides a non biaised estimation and avoids any perturbation induced by this phenomena. The algorithm, based on a maximum likehood estimator associated to a phase tracking loop, reaches theoretically the Cramer-Rao bound. Futhermore simulation results demonstrate the good practical behaviour of this system.