High-resolution modal wavenumber estimation in range-dependent shallow water waveguides using vertical line arrays

Area of Science:

• Ocean acoustics
• Geophysical signal processing

Background:

• Accurate modal wavenumber estimation is crucial for shallow water geoacoustic inversion and matched field processing.
• Range-dependent environments pose challenges due to spatially varying modal content and resolution requirements.

Purpose of the Study:

• To generalize high-resolution wavenumber estimation algorithms for synthetic horizontal aperture geometries.
• To evaluate the performance of these generalized methods using simulated shallow water acoustic data.

Main Methods:

• Generalization of matrix pencil and MUSIC algorithms for synthetic horizontal aperture (SHA) configurations.
• Utilizing a towed acoustic source and a fixed vertical line array (VLA) to form the SHA.
• Performance evaluation using simulated noisy shallow water data.

Main Results:

• The proposed methods demonstrate superior performance compared to existing techniques.
• Significant reduction in the required aperture size for accurate modal wavenumber estimation was achieved.
• Effective performance in a noisy shallow water environment was confirmed.

Conclusions:

• Generalized matrix pencil and MUSIC algorithms offer improved wavenumber estimation in range-dependent shallow water waveguides.
• The synthetic horizontal aperture approach effectively mitigates aperture limitations for modal analysis.
• These advancements are vital for enhanced geoacoustic inversion and acoustic signal processing.