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Polarization of ocean acoustic normal modes
Julien Bonnel1, Julien Flamant2, David R Dall'Osto3
1Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02540, USA.
The Journal of the Acoustical Society of America
|October 2, 2021
Summary
This study introduces a novel framework using Stokes parameters to describe the polarization of acoustic normal modes in shallow water. This method enhances the analysis of underwater sound propagation using particle velocity sensors.
Area of Science:
- Ocean acoustics
- Wave physics
- Signal processing
Background:
- Shallow water acoustic propagation is often modeled using normal mode propagation.
- Describing the polarization of these acoustic normal modes is crucial for a comprehensive understanding of underwater sound.
Purpose of the Study:
- To propose a framework for describing the polarization of acoustic normal modes in shallow water.
- To adapt the Stokes parameters, commonly used in light polarization, for acoustic wave analysis.
Main Methods:
- Theoretical derivation of Stokes parameters for acoustic normal modes.
- Development of a signal processing framework to estimate these parameters.
- Introduction of the polarization spectrogram for visualization using vector sensor data.
Main Results:
- The Stokes parameters for acoustic normal modes were theoretically derived.
- A practical signal processing method for estimating these parameters was introduced.
- The framework was successfully demonstrated on both simulated and experimental data.
Conclusions:
- The Stokes parameter framework offers a new approach to analyzing acoustic normal mode polarization in ocean acoustics.
- This framework opens up possibilities for applying established polarization analysis techniques from other fields to underwater acoustics.
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