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Source depth estimation in the presence of internal solitary waves based on matched mode function amplitude
Ziyu Zhang1,2, Chao Sun1,2, Lei Xie1,2
1School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an 710072, China.
The Journal of the Acoustical Society of America
|November 24, 2025
Summary
A new method using mode function amplitude (MFA) improves underwater source depth estimation in shallow waters, overcoming performance issues caused by internal solitary waves (ISWs) that affect traditional matched field processing (MFP) and matched mode processing (MMP).
Area of Science:
- Underwater acoustics
- Oceanography
- Signal processing
Background:
- Matched field processing (MFP) and matched mode processing (MMP) are used for source depth estimation in shallow water.
- Their performance degrades significantly in the presence of internal solitary waves (ISWs) due to feature sensitivity.
- Acoustic pressure and mode amplitude are susceptible to ISWs, causing field mismatches.
Purpose of the Study:
- To introduce a new feature, mode function amplitude (MFA), less sensitive to ISWs.
- To propose a novel processing method based on MFA for enhanced source depth estimation.
- To improve the accuracy and stability of source depth estimation in shallow water environments affected by ISWs.
Main Methods:
- Introduction of mode function amplitude (MFA) as a robust feature.
- Development of a matched mode function amplitude processing (MMFAP) method.
- Simulations to compare MMFAP with traditional MFP and MMP.
Main Results:
- MFA is less susceptible to ISWs compared to traditional features.
- The proposed MMFAP method demonstrates enhanced performance.
- Simulations confirm significantly higher accuracy and stability of MMFAP over MFP and MMP.
Conclusions:
- The MMFAP method effectively addresses the challenges posed by ISWs in shallow water.
- This approach offers a more reliable solution for underwater source depth estimation.
- The findings suggest a promising advancement in acoustic signal processing for oceanographic applications.
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