A new method to determine the complex permittivity and complex permeability of dielectric materials at X-band frequencies

Abstract

This paper presents a simple waveguide measurement technique to determine the complex permittivity and complex permeability of a dielectric material. The dielectric sample is loaded in the transmission line rectangular waveguide WR90. The S-parameters of the waveguide are measured by Network analyzer and calculated as a function of the complex permittivity and complex permeability using theory of transmissions lines. Using the MatLab Optimization Tools, a simple MatLab scripts is written to look for complex permittivity and complex permeability of a dielectric material so as to match the measured and calculated values of S-parameters. The complex permittivity and complex permeability of Teflon, Nylon and Delrin at the X-band frequencies are then determined.