A fast volume-surface integral equation solver for radiation and scattering from wire antennas, IBC surfaces and inhomogeneous dielectric objects

Dielectric materials are often involved in electromagnetic simulation for real-world problems. Previously, researchers have applied the fast multipole method and a hybrid volume-surface integral equation (VSIE) formulation to solve scattering problems involving both PEC and inhomogeneous dielectric objects. Although the above solver can solve scattering from electrically large objects with optimal computational complexity, it only involves surface and volume basis functions to model currents on PEC surfaces and in dielectric media. In order to solve problems involving additional types of scatterers and radiators, such as wire antennas, thin dielectric sheets, and impedance surfaces, we have enhanced the multilevel fast multipole code in Chao et al. (1998) with the impedance boundary condition (IBC) and the hybrid VSIE formulation. The paper discusses how a variety of basis functions are incorporated into the hybrid VSIE formulation and the multilevel fast multipole algorithm (MLFMA).