Accession Number : ADA329498

Title :   Sediment Penetration of Underwater Mammalian Sonar Signals.

Descriptive Note : Annual rept. 15 Sep 96-14 Sep 97,

Corporate Author : TEXAS UNIV AT AUSTIN APPLIED RESEARCH LABS

Personal Author(s) : Chotiros, Nicholas P.

PDF Url : ADA329498

Report Date : 10 SEP 1997

Pagination or Media Count : 10

Abstract : The adopted approach for characterization of buried target detection by underwater mammalian sonars, as represented by the sonar of tursiops truncatus has three components: (1) direct measurement and analysis of acoustic signals incident on buried targets; (2) construction of acoustic penetration and target scattering model; and (3) deduction of detection and classification methods through reproduction of target insonification processes. It has been two years since the start of the project, but progress has not kept up with the original milestone chart due to a drastic rearrangement of the funding profile. At present, tasks (1) and (2) are in progress. Under task (1), although the completion of the full measurement system has been delayed by funding problems, signals have been recorded with a reduced system in collaboration with Naval Control, Command & Ocean Surveillance Center (NCCOSC), San Diego. Under task (2), a model for wide band acoustic penetration of ocean sediments has been developed to compute the penetration of dolphin sonar pulses, based on Biot's theory1 ,2 of acoustic propagation in water-saturated porous media. This approach is general enough to model a wide variety of sediments, and has been found particularly suitable for sandy sediments.

Descriptors :   *BURIED OBJECTS, *TARGET DETECTION, *SONAR SIGNALS, *DOLPHINS(MAMMALS), MODELS, ACOUSTIC WAVES, TARGETS, BROADBAND, SOUND TRANSMISSION, ACOUSTIC MEASUREMENT, ACOUSTIC SCATTERING, SEDIMENTS, OCEAN BOTTOM, UNDERWATER, SONAR PULSES.

Subject Categories : Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE