Broadband localization by matched fields in range and bearing in shallow water.

Data from a moving source received by three horizontally separated bottomed sensors in a shallow water environment are analyzed using a broadband matched-field approach to source localization. The water depth was approximately 150 m, and the low bottom loss in the area results in low spatial coherence of the broadband field. The modeled acoustic fields are constructed via a ray model. Localizations are made in the x-y plane. In a large search area the time evolution of the ambiguity surfaces produced from the data agree fairly well with simulated surfaces. Ambiguity surfaces are generated successively at intervals of about 1.6 s in small search areas with a fine spatial grid to test the possibility of tracking a source. Results of the source tracking are presented. The analysis also considers the effects of the sea floor on localization in the context of spatial coherence. [ABSTRACT FROM AUTHOR]