Aspects of Signal Processing pp 251-256 | Cite as
The Role of Coherence in Time Delay Estimation
Abstract
This paper investigates methods for passive estimation of the bearing to a slowly moving acoustically radiating source. The mathematics for the solution to such a problem is analogous to estimating the time delay (or group delay) between two time series. Since the estimation of time delay is intimately related to the coherence between two time series, a summary of the properties of coherence is presented
The maximum likelihood (ML) estimate of time delay (under jointly stationary Gaussian assumptions) is presented. The explicit dependence of time delay estimates on coherence is evident in the estimator realization in which the two time series are prefiltered (to accentuate frequency bands according to the strength of the coherence) and subsequently crosscorrelated. The hypothesized delay at which the generalized crosscorrelation (GCC) function peaks is the time delay estimate. The variance of the time delay estimate is presented and discussed.
Keywords
Group Delay Function Peak Power Spectral Density Function Time Delay Estimate Receive WaveformPreview
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