Barankin bounds for source localization in an uncertain ocean environment

Ambiguity surfaces for underwater acoustic matched-field processing are pro ne to having high secondary peaks. This leads to anomalous source localizat ion estimates below a threshold signal-to-noise ratio (SNR) at which the pe rformance rapidly departs from that predicted by the Cramer-Rao lower bound (CRLB), In this paper, Barankin bounds are used to predict the threshold S NR under two different models including known or uncertain shallow mater en vironments and monochromatic or random narrowband sources. Evaluation of th e Barankin bound suggests that although asymptotic localization performance degrades with increasing environmental uncertainty, the threshold SNR is r elatively unaffected.