Understanding and mitigating the impact of passing ships on underwater environmental estimation from ambient sounda)

  • 0Department of Electrical and Computer Engineering, Portland State University, 1900 Southwest 4th Avenue, Suite 160, Portland, Oregon 97201, USA.

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Summary

This summary is machine-generated.

Low-rank interference degrades seabed type discrimination using ambient sound. A novel method reconstructs interference-free data, enabling accurate acoustic seabed analysis and improving bottom loss estimation.

Area Of Science

  • Acoustic signal processing
  • Geophysical remote sensing
  • Statistical hypothesis testing

Background

  • Distinguishing seabed types relies on analyzing acoustic data, often using covariance matrices.
  • Box's M-test is a standard method for comparing seabed types based on covariance.
  • Low-rank interference, like ship noise, can significantly impair the accuracy of these tests.

Purpose Of The Study

  • To investigate the performance degradation of seabed type discrimination due to low-rank interference.
  • To develop a method for mitigating the effects of such interference in acoustic data.
  • To improve the accuracy of hypothesis testing for seabed characterization and bottom loss estimation.

Main Methods

  • Formulated seabed type discrimination as a two-sample hypothesis test for covariance equality.
  • Developed a method to construct a worst-case low-rank interference field.
  • Implemented an alternating optimization procedure to recover the interference-free covariance matrix.

Main Results

  • Constructed interference significantly degraded hypothesis testing performance in synthetic experiments.
  • The proposed recovery method effectively eliminated interference for small interference ranks.
  • Real-world experiments demonstrated successful interference mitigation and improved bottom loss estimation.

Conclusions

  • Low-rank interference poses a significant challenge to acoustic seabed discrimination.
  • The developed interference recovery technique enhances the reliability of hypothesis testing.
  • This approach offers a practical solution for improving seabed characterization in noisy acoustic environments.

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