Removing Fabry-Pérot artifacts for electromagnetic homogenization of lossless and lossy dielectric composites based on scattering parameters

An efficient method to restore the physically reasonable macroscopic dispersive electromagnetic parameters of periodic dielectric composites is proposed. Physical explanation and mathematical formulation of the proposed method are elucidated. By determining the effective thickness of the composite slab at each single frequency, the proposed method targets on correcting the inappropriately defined impedance, an intermediate parameter in the retrieval process into which the broadband Fabry-Pérot artifacts are introduced. Moreover, one advantage of the method lies in that it does not require a priori information from preceding frequency points. Finally, numerical simulations are performed for both lossless and lossy dielectric composite slabs, which demonstrate the validity of the proposed method.