Determination of complex permittivity and permeability of materials in rectangular waveguide using accurate hybrid numerical calculation

An effective simultaneous evaluation method for the complex permittivity and permeability of the specimen filling partially the rectangular waveguide is proposed. Electromagnetic field analysis for the evaluation is based on the extended spectral domain approach combined with the mode-matching method (ESDMM). ESDMM is accurate and more efficient than FEM and suitable for the iterative fitting to estimate the material characteristics. Microwave absorbing rubber sheet was measured over the X-band by the present method. The sample preparation and setting are far easy compared with conventional method, because it is not necessary to fill exactly the cross section of waveguide. The evaluated results by ESDMM for the several samples have showed good agreement with ones measured by conventional method.