Accession Number : ADA305987
Title : Modeled High-Frequency Acoustic Backscattered Levels from Range-Independent and Simplistic Range-Dependent Sand Bottoms.
Descriptive Note : Final rept.,
Corporate Author : NAVAL RESEARCH LAB STENNIS SPACE CENTER MS
Personal Author(s) : Savage, Kristen D. ; Meredith, Roger W.
PDF Url : ADA305987
Report Date : 21 FEB 1996
Pagination or Media Count : 17
Abstract : Results investigating the effects of variable bottom composition on modeled high-frequency backscattered levels are presented for a typical shallow-water, variable bottom (range-dependent) environment. The modeled environment consisted of a single sound speed profile, a flat sea bottom with range-dependent bottom composition, and a smooth, flat sea surface. Coarse-and fine-grained sandy areas were partitioned in range to create range dependence. Bottom backscattering and reflection loss for each partition were obtained from the recent University of Texas high-frequency ocean bottom backscatter model (N. P. Chotiros and F. A. Boyle, J. Acoust. Soc. Am., vol. 96, no. 5, pt. 2, 3264, (1994)). Maximum differences of S dB were discernible between the fine- coarse-fine sand bottom and a range-independent fine-sand bottom for ranges <500 m. The trend and structure of the backscattered levels were nearly identical for both bottom types. In all cases, surface reverberation had a strong impact on the backscattered levels, trends, and structures. (MM)
Descriptors : *ACOUSTIC SCATTERING, *SONAR, *MINE DETECTORS, *ACOUSTIC COUNTERMEASURES, OCEAN SURFACE, MINE COUNTERMEASURES, GRAIN SIZE, SAND, BACKSCATTERING, SHALLOW WATER, RAY TRACING, REVERBERATION, ACOUSTIC VELOCITY, SOUND PRESSURE, OCEAN BOTTOM SOILS, ACOUSTIC REFLECTION.
Subject Categories : Acoustic Detection and Detectors
Distribution Statement : APPROVED FOR PUBLIC RELEASE