FDTD Analysis of Electromagnetic Scattering Sheet Using Surface Impedance Method

Electromagnetic scattering sheet (EMSS) is a structure which can diffuse an incoming EM field to many different directions. EMSS can be configured with a specific combination of perfectly electric conductor (PEC) and perfectly magnetic conductor (PMC). To analyze the EMSS, collocation of both electric and magnetic fields at the medium surface is required, which is not compatible with the conventional FDTD method. To address this problem, the fast inverse Laplace transform and Prony method is applied to incorporate the surface impedance of an electric conductor with σ = 58×10
¹⁰
S/m to model a PEC while a PMC is modeled by enforcing the magnetic field at the medium surface to be zero. Validation of the PEC modeling is confirmed from 1D simulation results. Scattering cross section of the EMSS is calculated and compared with the result obtained by the method of moments.