Quantitative ambiguity analysis for matched-field source localization

Matched-field methods find source location by matching the measured 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 an increased localization error. To analyze this threshold performance behaviour, a quantitative approach for error analysis is developed in the context of the maximum likelihood estimate (MLE) and generalized to include environmental uncertainty.