The impedance boundary condition implementation for the 3D random auxiliary sources method

The Random Auxiliary Sources (RAS) method is used to solve the electromagnetic scattering problem from structures with impedance boundary conditions. Basically, the RAS method exploits a uniformly distributed random infinitesimal electric/magnetic dipoles as the expansion function, where their unknown amplitudes are used to directly satisfy the boundary conditions. Typically, the flexibility of the formulation and implementation of the developed RAS method enables an easy adaptation for arbitrary boundary conditions. The results of the proposed implementation are compared to analytical expressions for canonical geometries as well as the full-wave analysis of HFSS of several cases.