Characterization of relative complex permittivity and permeability for magneto-dielectric sheets

A new method is developed to extract relative complex permittivity and permeability of magneto-dielectric sheets. Two test fixtures are used to separately extract electric and magnetic properties of the material under test (MUT). The unknown parameters corresponding to dispersion models of the complex permittivity and permeability of the magneto-dielectric sheet are optimized by comparing the measured |S₂₁| of the test fixtures containing the MUT with the |S₂₁| obtained from full-wave simulation. CST Microwave Studio is used to perform the simulations and optimization. The method is verified and the extracted electromagnetic properties of two ferrite sheet samples are presented. Also, the uncertainty of the system due to air gaps in the test fixtures is investigated.