The Generalized Correlation Method for Estimation of Time Delay

作     者：Knapp, Charles H. Carter, G. Clifford 

作者机构：Department of Electrical Engineering and Computer Science University of Connecticut Storrs CT 06268 United States Naval Underwater Systems Center New London Laboratory New London CT 06320 United States 

出 版 物：《IEEE Transactions on Acoustics, Speech, and Signal Processing》 (IEEE Trans. Acoust. Speech Sign. Proces.)

年 卷 期：1976年第24卷第4期

页      面：320-327页

主　　题：Correlation Delay estimation Delay effects Maximum likelihood estimation Correlators Propagation delay Frequency Signal to noise ratio Signal processing Mathematical model 

摘      要：A maximum likelihood (ML) estimator is developed for determining time delay between signals received at two spatially separated sensors in the presence of uncorrelated noise. This ML estimator can be realized as a pair of receiver prefilteis followed by a cross correlator. The time argument at which the correlator achieves a maximum is the delay estimate. The ML estimator is compared with several other proposed processors of similar form. Under certain conditions the ML estimator is shown to be identical to one proposed by Hannan and Thomson [10] and MacDonald and Schultheiss [21]. Qualitatively, the role of the prefilters is to accentuate the signal passed to the correlator at frequencies for which the signal-to-noise (S/N) ratio is highest and, simultaneously, to suppress the noise power. The same type of prefiltering is provided by the generalized Eckart filter, which maximizes the S/N ratio of the correlator output. For low S/N ratio, the ML estimator is shown to be equivalent to Eckart prefiltering. Copyright © 1976 by The Institute of Electrical and Electronics Engineers, Inc.