A DBS Doppler Centroid Estimation Algorithm Based on Entropy Minimization

Doppler centroid is a key focusing parameter of Doppler beam sharpening (DBS) imaging. According to the locked relationship between Doppler centroid error and image entropy, a minimum-entropy Doppler estimator (MEDE) is proposed. The algorithm breaks the conventional algorithms´ assumption that the shape of echo signal´s power spectrum is symmetrical, and the proposed method can circumvent the problem of low estimation precision using conventional algorithms to process the echo signal from high-scene contrast. The new algorithm based on entropy minimization has high estimation precision in the case of low- and high-scene contrast. MEDE has been successfully applied to a DBS real-time imaging processor of airborne radar and verified by flight experiments.