A weighted-average scheme for accurate FDTD modeling of electromagnetic wave propagation in conductive media

The letter presents a new finite-difference scheme for the incorporation of conductive media into finite-difference time-domain (FDTD) simulators. The method is based on the approximation of the current density term by a weighted average with coefficients that are not known a priori. The optimum values of these coefficients are determined by minimizing the dispersion error inside the conductor. The cases of single-frequency and wide-band FDTD simulations are discussed. The superior performance of the proposed scheme over other existing approaches is shown.