FDTD modeling of absorbing materials for EMI applications

A few scenarios of applying different magneto-dielectric absorbing sheet materials to mitigate electromagnetic inference (EMI) are analyzed in this paper using a full-wave 3D finite-difference time-domain (FDTD) technique. Frequency characteristics of both permittivity and permeability of these magneto-dielectric materials are approximated by the series of the Debye terms suitable for time-domain simulations. This approximation is accomplished using a new curve fitting technique based on the Legendre polynomials and the regression analysis optimization. The results of the numerical simulations are verified by the corresponding experiments, and the good agreement is obtained.