Characterization of ferrimagnetic and dielectric materials with a rectangular waveguide-method, limits of validity

The development of passive components in the microwave range for telecommunication applications is a major focus for the next years. Some microwave passive components (such as circulators, isolators, etc.) still use magnetic materials. It is then necessary to characterize the electromagnetic properties of such materials, their scattering behaviours and to eventually highlight a non-reciprocal propagation. A method for the dielectric and magnetic characterization of multi-layer materials in the X-band (8.2-12.4 GHz) is presented as well as its reliability and its domain of validity. It allows to determine the elements of the permeability tensor of ferrite sample.