Abstract:

The depth discrimination capability of matched-field processing provides the possibility of separating surface from submerged sources of acoustic energy. Data collected in 200-m water during SWellEx-96 will be used to illustrate the achieved depth resolution in a downward refracting, shallow-water environment. During the event analyzed, two sources were towed simultaneously. The nominal depths of the deep and shallow sources were 60 and 10 m, respectively. Both projected unique, multitone transmissions with the deep source covering the 50--400 Hz band and the shallow source covering the 100--400 Hz band. In addition, the source ship herself (R/V Sproul) had a detectable radiated acoustic signature across this same frequency region. The data were received by a 120-m aperture, 64-element vertical array deployed from the R/P FLIP. Broadband adaptive matched-field processing has been carried out on the data. The depth resolution characteristics of each of the three sources of acoustic energy will be presented. [Work supported by ONR, Code 321US.]