Title :
The measurement of the permittivity of sheet materials at microwave frequencies using an evanescent waveguide technique
Author :
Kumar, Akhileshwar ; Smith, D. Geoffrey
Author_Institution :
Dept. of Electronic Sci. & Telecommunications, Univ. of Strathclyde, Glasgow, UK
Abstract :
Based on a method first proposed by Barlow (1962) the paper discusses how the complex permittivity of a sheet material can be determined by measuring the Q and frequency change produced by a sample when it is placed in a circular evanescent waveguide which is coupled to a resonant cavity. The method appears to be satisfactory for dielectric materials with loss tangents above about 0.01. Measurements on two mixtures of polystyrene and carbon, taken at 9 GHz, are reported.
Keywords :
microwave measurement; permittivity measurement; Barlow´s method; Q-factor measurement; complex permittivity; evanescent waveguide technique; frequency change measurement; loss tangents above 0.01; measurements at 9 GHz; permittivity at microwave frequencies; permittivity measurement; permittivity of sheet materials; resonant cavity coupled to waveguide; Cavity resonators; Couplings; Frequency measurement; Permittivity; Permittivity measurement; Q measurement;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.1976.6312344
