Quantitive ambiguity analysis for matched-field source localization under spatially-correlated noise field

Matched-field methods find source location by matching the measured signal field with the modeled signal field. The resulted ambiguity output is often characterized by a multimodal structure. At high signal-to-noise ratio (SNR), the peak at the true source position is a global maximum and can be located accurately; below some threshold SNR, the true peak is easily obscured by other ambiguous peaks, leading to a significantly increased localization error. To analyze this threshold performance behavior, a quantitative approach for error analysis has previously been developed in the context of the maximum likelihood estimate (MLE) with spatially-white noise [(W. Xu, et al., 2002), (W. Xu, 2001)]. In this paper, the same approach is generalized to work for spatially-correlated noise field introduced by discrete interferences and/or surface distribution sources.