Novel Evaluation Method of the Complex Dielectric Constant of High-Permittivity Material at Microwave Frequency

Abstract

A novel accurate measurement method for high-permittivity materials in the microwave region, by adopting a discontinuity structure in the coaxial transmission line, is proposed. Electromagnetic field analysis is carried out using the extended spectral domain approach in combination with the mode-matching method (ESDMM). Numerical results obtained by ESDMM are compared with the values obtained by the finite element method (FEM) and excellent agreement is observed. However, ESDMM is more efficient in numerical computations and can be utilized for the iterative fitting of the measured values to identify the material. A simple but practically effective characterization method for high-permittivity materials at microwave frequency was developed.