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Accession Number ADA571588
Title Acoustic Coherent Backscatter Enhancement from Aggregations of Marine Animals.
Publication Date Sep 2011
Media Count 4p
Personal Author D. R. Dowling
Abstract LONG-TERM GOALS: The overall long-term goal for this project is to determine if and how acoustic coherent backscatter enhancement (ACBE) can be used for classification of active sonar returns in a wide variety of ocean environments. During its first eight months, this project has focused on elementary simulations of acoustic multiple scattering from aggregations of omni-directional scatterers to determine the parametric realms in which ACBE might be observed. OBJECTIVES: The detailed objectives of the current research effort are to determine the parametric dependence of ACBE peak amplitude, peak emergence rate, peak angular width, and peak time dependence. Here the independent parameters are source-scatterer range, receiving array characteristics, incident wave characteristics (wave type, waveform, frequency, bandwidth, duration), and aggregation characteristics (scatterer cross section, mean spacing, resonant frequency, overall size, etc.). Eventually, underwater waveguide characteristics will be considered as well.
Keywords Acoustic scattering
Aquatic animals
Coherent radar
Cross sections
Long range(Time)
Parametric analysis
Peak values
Resonant frequency
Time dependence

Source Agency Non Paid ADAS
NTIS Subject Category 57C - Botany
57Z - Zoology
47C - Physical & Chemical Oceanography
46A - Acoustics
Corporate Author Michigan Univ., Ann Arbor. Dept. of Mechanical Engineering.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1316
Contract Number N00014-11-1-0258

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