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Reverberation due to a moving, narrowband source in an ocean waveguide
Brian T Hefner1, William S Hodgkiss2
1Applied Physics Laboratory, University of Washington, 1013 NE 40th Street, Seattle, Washington 98105, USA.
The Journal of the Acoustical Society of America
|October 9, 2019
Summary
This study presents a new model for ocean acoustic reverberation from a moving source, revealing a wide Doppler spread in scattered sound. This model aids in understanding seafloor scattering and its applications in seafloor characterization.
Area of Science:
- Ocean acoustics
- Acoustic reverberation
- Waveguide propagation
Background:
- Doppler effect studies in waveguides typically focus on forward propagation.
- Scattered sound from moving sources exhibits a broader Doppler shift spectrum.
Purpose of the Study:
- Develop a model for bistatic reverberation from a moving source in an ocean waveguide.
- Investigate Doppler reverberation for seafloor characterization.
Main Methods:
- Modeled incident sound field using rays.
- Applied ray-mode analogies for seafloor scattering.
- Propagated scattered sound to the receiver using normal modes.
Main Results:
- The developed model accounts for the full range of Doppler shifts in scattered sound.
- Model results were validated against experimental data from the Target and Reverberation Experiment 2013.
Conclusions:
- The model accurately describes bistatic reverberation from a moving source.
- Doppler reverberation shows potential for seafloor characterization.
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