A Fast Prediction Method for Wide-Angle Bistatic Scattering and Reflection Coefficients of Acoustically Coated Plates

Area of Science:

• Acoustics
• Materials Science
• Signal Processing

Background:

• Multistatic sonar enhances underwater target detection.
• Accurate wide-angle bistatic scattering data is crucial for system performance and acoustic coating design.
• Experimental measurements and conventional finite-element method (FEM) simulations face challenges in obtaining full-angle scattering characteristics.

Purpose of the Study:

• To develop a fast and accurate method for predicting wide-angle scattering from acoustically coated plates.
• To enable efficient evaluation of bistatic reflection coefficients for complex targets and environments.
• To provide a foundation for rapid target strength prediction using the Planar Element Method.

Main Methods:

• Constructing a scattering transfer matrix from surface mesh data.
• Retrieving equivalent source density from a limited set of scattered pressure samples.
• Reconstructing the full-angle scattering field and extracting reflection coefficients.

Main Results:

• The proposed method accurately reproduces bistatic reflection coefficients for rigid and coated plates.
• Predictions align with finite-element calculations, capturing non-linear dispersion and interference fringes.
• The method demonstrates high accuracy across a wide frequency band (100 Hz to 5 kHz).

Conclusions:

• The developed method significantly reduces computational time compared to traditional FEM sweeps.
• It offers an efficient tool for designing acoustic stealth materials.
• This approach lays the groundwork for rapid target strength prediction of complex targets.