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Published on: September 27, 2024
Fluctuating arrivals of short-range acoustic data
Cheolsoo Park1, Woojae Seong, Peter Gerstoft
1Maritime and Ocean Engineering Research Institute (MOERI), Daejeon 305-343, Korea.
The Journal of the Acoustical Society of America
|February 10, 2011
Summary
Understanding signal fluctuations is key for geoacoustic inversion. Experiments show that a strong thermocline and ocean surface wave motion cause these signal variations in shallow waters.
Area of Science:
- Ocean acoustics
- Marine geophysics
Background:
- Geoacoustic inversion relies on acoustic signal analysis.
- Signal fluctuations complicate accurate inversion.
- Previous studies lacked clear explanations for observed fluctuations.
Purpose of the Study:
- To investigate the origin of signal fluctuations in shallow water acoustic transmissions.
- To correlate signal variations with environmental factors and source motion.
Main Methods:
- Analysis of acoustic signal arrival amplitudes from short-range chirp transmissions.
- Experiments conducted in shallow water near the New Jersey shelf break.
- Utilized a vertical line array to record acoustic data.
Main Results:
- Observed significant fluctuations in direct path and surface-reflected arrivals.
- Identified a strong thermocline as a key contributing factor.
- Demonstrated that oscillating source motion from ocean surface waves also drives fluctuations.
Conclusions:
- The combined effects of a strong thermocline and source motion due to surface waves explain the observed signal fluctuations.
- Understanding these origins is crucial for appropriate use of signals in geoacoustic inversion.
- This research clarifies a significant challenge in underwater acoustic signal processing.
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