Concerning measurements of high complex permittivity by the resonator perturbation method

Abstract

The measurement of complex permittivity at radio and microwave frequencies by means of a resonator may be based on the filling factor concept. With high permittivities, a simple approximation unfortunately is not satisfactory. As an extension of this principle, a high-order approximation is given for the case of a plane, transverse sample at an electric field node; this is compared with exact solutions. Further, it is adapted to the related problem of dielectric loss measurement of liquids contained in a tube within a waveguide resonator of the TE10n type. The result is a relation with three parameters, instead of one, to be adjusted by calibration.