Frequency dependent finite‐difference–time‐domain [(fd) 2 td] formulation applied to ferrite material

When subjected to a constant magnetic field, ferrites exhibit anisotropic constitutive parameters. This anisotropy can be described in the frequency domain by using a permeability tensor [μ(ω)] instead of the usual scalar permeability. This article introduces a new method to analyze saturated ferrite structures by a FDTD algorithm where the convolution between the permeability tensor [μ(t)] = F −1 ([μ(ω)]) and the magnetic field H(t) = F −1 (H(ω)) are to be calculated. Results are obtained for a two‐dimensional problem and are compared with those given by direct differential FDTD algorithm [1] and a mode‐matching method [2]. © 1994 John Wiley & Sons, Inc.