A Microwave Method for the Determination of the Real Parts of the Magnetic and Dielectric Material Parameters of Premagnetized Microwave Ferrites

A microwave method is presented for the determination of the real parts of the magnetic and dielectric material parameters of premagnetized microwave ferrites. It is based on the simultaneous utilization of certain dynamic modes that occur in a cylindrical cavity partly filled with a ferrite sample. Employing the corresponding eigenvalue equations of these modes, the material parameters are computed from the measured resonant frequencies of the cavity. In contrast to other techniques, the described method requires only a single cavity and a single, easily produced sample of the ferrite material to be examined. The evaluation of the measurements can be done with a simple desk-top computer. The material parameters of two different ferrite materials have been measured and found to be in satisfactory agreement with parameters calculated from formulas based on model conceptions.