Finite Difference Time Domain (FDTD) Impedance Boundary Condition for Thin Finite Conducting Sheets

Abstract–A new Impedance Boundary Condition (IBC) for two dimensional Finite Difference Time Domain simulations containing thin, good conductor sheets is presented. The IBC uses a recursive convolution scheme based on approximating the conductor’s impedance as a sum of exponentials. The effects of FDTD parameters such as grid size and time step on simulation accuracy are presented. The IBC verification is performed by comparing the quality factors of rectangular resonant structures determined by the FDTD simulation and analytical methods. The IBC is shown to accurately model the conductor loss over a wide frequency range.