Scattering-Based Characteristic Mode Theory for Structures in Arbitrary Background: Computation, Benchmarks, and Applications

TL;DR

This paper introduces a scattering-based characteristic mode theory that simplifies electromagnetic analysis of structures, offering improved efficiency, flexibility across numerical methods, and benchmark solutions for validation.

Contribution

A novel scattering matrix approach for substructure characteristic mode computation that is independent of specific numerical frameworks and enhances computational efficiency.

Findings

Developed analytical solutions for two-sphere structures as benchmarks.

Achieved improved numerical dynamics and efficiency over traditional impedance matrix methods.

Demonstrated the method's flexibility across different numerical techniques.

Abstract

This paper presents a novel approach for computing substructure characteristic modes. This method leverages electromagnetic scattering matrices and spherical wave expansion to directly decompose electromagnetic fields. Unlike conventional methods that rely on the impedance matrix generated by the method of moments (MoM), our technique simplifies the problem into a small-scale ordinary eigenvalue problem, improving numerical dynamics and computational efficiency. We have developed analytical substructure characteristic mode solutions for a scenario involving two spheres, which can serve as benchmarks for evaluating other numerical solvers. A key advantage of our method is its independence from specific MoM frameworks, allowing for the use of various numerical methods. This flexibility paves the way for substructure characteristic mode decomposition to become a universal frequency-domain technique.