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Surficial sediment sound speed estimation from wide-angle multipath arrivals
Linus Y S Chiu1, Ying-Tsong Lin2
1Institute of Undersea Technology, National Sun Yat-sen University, Kaohsiung, Taiwan.
JASA Express Letters
|December 1, 2022
Summary
Seabed properties influence underwater acoustic signals. This study shows how to use acoustic arrival time delays and critical angle points to estimate sediment sound speed and attenuation, validated with experimental data.
Area of Science:
- Ocean acoustics
- Geophysical exploration
- Underwater acoustics
Background:
- Multipath acoustic arrivals in underwater waveguides are influenced by seabed properties.
- Wide-angle bottom reflections provide data for seabed geoacoustic parameter estimation.
Purpose of the Study:
- To theoretically analyze the effects of seabed properties on multipath acoustic arrivals.
- To develop a method for estimating sediment sound speed and attenuation using acoustic data.
Main Methods:
- Theoretical analysis of acoustic wave propagation in underwater waveguides.
- Identification of critical angle points in multipath arrivals.
- Utilizing time delays and source distances at critical angles for parameter estimation.
Main Results:
- Sediment sound speed can be determined from time delays and source distances at critical angle points.
- The influence of sediment attenuation on acoustic measurements is discussed.
- The proposed method was successfully demonstrated with experimental data.
Conclusions:
- Multipath acoustic arrivals offer a viable method for seabed geoacoustic parameter estimation.
- The study provides a practical approach for determining sediment sound speed and attenuation in underwater environments.
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