Accession Number : ADA297423

Title :   Sediment Effect on Matched-Field Processing for a Multidimensional Array in a Deep-Water Atlantic Environment.

Descriptive Note : Final rept. 1991-1992,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Yoo, Kwang B. ; Heitmeyer, Richard M.

PDF Url : ADA297423

Report Date : 18 JUL 1995

Pagination or Media Count : 31

Abstract : Sediment-interacting energy plays an important role in matched-field processing (MFP) and provides a range-sensitive component to the regular periodic waterborne convergence zone (CZ) structure. This report presents the results of a systematic MFP simulation analyses of a strong sediment-interacting environment in the Sargasso Sea area. The MFP power output was computed using a tripod-shaped multidimensional array. The results show that the relative strength of the sediment-interacting energy to the waterborne energy received at the array is critical to successful detection localization performance. The MFP performance thus depends on the source range and frequency. The sediment mismatch degradation is more sensitive to the initial sediment sound speed than to the sound-speed slope or the attenuation parameters. The sediment layer thickness has virtually no effect on the mismatch degradation when the thickness is greater than 200 m for long-range MFP. A small change (0.1 %) of the water column depth, however, created a considerable degradation. There is an indication that small errors in water depths may be tolerable in a case of range-dependent bathymetry, if a reasonably accurate average depth is used. (AN)

Descriptors :   *SEDIMENTS, *ACOUSTIC FIELDS, *SARGASSO SEA, COMPUTERIZED SIMULATION, DEGRADATION, PARAMETERS, ENERGY, DEPTH, GEOACOUSTICS, BATHYMETRY, ACOUSTIC ARRAYS, SOUND TRANSMISSION, SLOPE, ACOUSTIC ATTENUATION, ATLANTIC OCEAN, RANGE(DISTANCE), MIXED LAYER(MARINE), UNDERWATER ACOUSTICS, ACOUSTIC VELOCITY, DEEP WATER, TRANSMISSION LOSS, SOUND RANGING, WATERBORNE, CONVERGENCE ZONES.

Subject Categories : Physical and Dynamic Oceanography
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE