An Accelerated GSTC-based Integral Equation Method using Characteristic Basis Functions for Metasurface-Based Radar Absorbing Material

This paper proposes an accelerated integral equation method using the characteristic basis function(CBF) for metasurface-based radar absorbing material. The metasurfaces are converted into zero-thickness sheets having specific surface susceptibilities which satisfy the generalized sheet transition conditions (GSTCs) in our formulation. To address general problems, we consider the geometry of composite structures in which the PEC surface and metasurface are combined to each other. The characteristic basis functions (CBFs) are used to reduce the number of unknowns to analyze problems including electrically large metasurfaces. We provide various numerical simulation results to validate the accuracy of the proposed method by comparing the results from commercial FEM-based full-wave simulation. Also, we conduct the evaluation and optimization for enhancing the performance of our method.