Electromagnetic scattering by a circular cylinder buried below a slightly rough Gaussian surface

Area of Science:

• Electromagnetics and Acoustics
• Wave Scattering Theory
• Surface Physics

Background:

• Understanding wave scattering from subsurface objects is crucial in various fields, including geophysics and non-destructive testing.
• Previous models often simplify surface roughness or object geometry, limiting their applicability.
• Accurate modeling requires accounting for both the buried scatterer and the surface characteristics.

Purpose of the Study:

• To develop a robust theoretical framework for analyzing two-dimensional wave scattering by a buried cylinder beneath a slightly rough surface.
• To integrate cylindrical wave expansions with spectral methods and small perturbation techniques.
• To validate the approach for a periodic surface with a Gaussian roughness spectrum.

Main Methods:

• Utilizing cylindrical waves as basis functions for scattered fields from the cylinder.
• Employing spectral representation for incident fields and cylindrical waves.
• Applying the first-order small perturbation method to account for surface roughness.
• Superimposing a first-order approximation onto a zeroth-order solution for a flat surface.

Main Results:

• The theoretical framework successfully models wave scattering from a buried cylinder under a rough surface.
• The method provides a zeroth-order solution for flat surfaces, enhanced by a first-order approximation for roughness.
• Implementation demonstrates effective analysis for periodic surfaces with Gaussian roughness spectra.

Conclusions:

• The combined cylindrical wave and perturbation method offers a powerful tool for analyzing complex scattering scenarios.
• This approach enhances the accuracy of modeling wave interactions with buried objects in the presence of surface irregularities.
• The findings have implications for subsurface sensing and characterization techniques.