ASA 127th Meeting M.I.T. 1994 June 6-10

4pUW9. Matched-field processing and source depth localization in a shallow-water environment (SWellEX-1).

P. Schey

F. Ryan

Ocean and Atmospheric Sci. Div., CODE 541, NRaD, San Diego, CA 92152-5000

During 2 weeks in August 1993, a high-fidelity acoustic experiment, SWellEX-1, was conducted in shallow waters off San Diego, CA. The SWellEX-1 site is a 50 to 200-m bottom-limited shallow-water environment characterized by strong range dependence in both bottom and water column properties. Calibrated broadband and tonal signals from a projector in the band 70--750 Hz were received on a 48-channel, 90-m aperture vertical line array (VLA) spanning the lower half of the water column. Source tows are depths from 15--100 m were conducted along isobaths and up-slope relative to the VLA. Results of source depth localization using plane-wave processing (omega-k plots) and matched-field tracking will be presented. Depth localization via matched-field processing with high-fidelity replica vectors generated using both range-dependent and range-independent models will be compared. The impact of bottom geoacoustic properties ``mismatch'' on matched-field processing will be discussed. [Work supported by ONR under NRaD block CS3A.]