The effects of signal-to-noise ratio mismatch on Bayesian matched-field source localization performance

The signal-to-noise ratio of real data is rarely known with complete certainty. However, Bayesian matched-field processing techniques for ocean acoustic source localization often require the signal-to-noise ratio (SNR) to be known a priori. In this paper, the effects of SNR mismatch on the performance of a Bayesian matched-field source localization method, the optimum uncertain field processor (A.M. Richardson and L.W. Nolte, J. Acoust. Soc. Am. vol.89, no.5, 2280-4 (1991)), are investigated. Theoretical and empirical analyses show that when the maximum a posteriori (MAP) estimate is utilized as the source location estimate, the localization performance is unaffected by the uncertainty regarding the SNR, provided that the assumed SNR is sufficiently high