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Accession Number ADA571701
Title Spatio-Temporal Characterization of Bio-Acoustic Scatterers in Complex Media.
Publication Date Sep 2011
Media Count 5p
Personal Author K. G. Sabra
Abstract LONG TERM GOALS: To develop a methodology for extracting the relevant spatial and temporal scales of bio-acoustic scatterers based on multi bi-static long-range measurements in shallow water waveguides. OBJECTIVE Characterization of biologically-induced ocean reverberation features is key to effectively parametrize acoustic models and thus ultimately improve the detection performance of long-range SONAR systems. Ocean reverberation signals measured in shallow water can be thought to result from the combined effect of both two- way multipath acoustic propagation and the intrinsic scattering function of compact (e.g. fish aggregates or submerged target) or extended (e.g. rough seabed) acoustic inhomogeneities. In particular, multipath effects in shallow water effectively yield multiple probing of the complex scattering function of fish aggregates or marine mammals. This complexity of the acoustic propagation and biological scattering prevents the use of conventional remote sensing techniques for mid-frequency long-range SONAR systems.
Keywords Aggregates(Materials)
Aquatic animals
Bioacoustics
Biological agents
Bistatic detection
Detection
Extraction
Fishes
Mammals
Media
Methodology
Multipath transmission
Ocean bottom
Oceans
Propagation
Reverberation
Roughness
Scattering
Shallow water
Signals
Sonar
Sound transmission
Spatial distribution
Underwater targets
Water
Yield

 
Source Agency Non Paid ADAS
NTIS Subject Category 98F - Fisheries & Aquaculture
63D - Magnetic Detection
47D - Biological Oceanography
Corporate Author Georgia Inst. of Tech., Atlanta. School of Mechanical Engineering.
Document Type Technical report
Title Note Annual rept.
NTIS Issue Number 1316
Contract Number N/A

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