Experimental technique for high-frequency conductivity measurement

• Published in: Compel Vol. 38; no. 5; pp. 1711 - 1722
• Main Authors: Marák, Károly, Bilicz, Sándor, Pávó, József
• Format: Journal Article
• Language: English
• Published: Bradford Emerald Publishing Limited 21-10-2019; Emerald Group Publishing Limited
• Subjects: Accuracy; Anisotropy; Backscattering; Carbon fiber reinforcement; Carbon fibers; Composite materials; Conductivity; Design parameters; Doppler effect; Electric fields; Experiments; Inverse problems; Investigations; Methods; Physical properties; Resonance scattering; Conductivity measurement; Micro-Doppler effect; Carbon fiber composites; Composite material; Material parameters
• ISSN: 0332-1649; 2054-5606
• DOI: 10.1108/COMPEL-12-2018-0502

Purpose
The purpose of this study is to introduce a novel method for the measurement of electromagnetic material parameters.
Design/methodology/approach
The main idea behind the approach is the fact that for slabs with elongated shapes, the intensity of the backscattered field and the electromagnetic resonance frequency corresponding to the length of the sample are dependent on the conductivity of the sample’s material.
Findings
It is shown that for a known scattered field and resonance frequency, it is possible to formulate an inverse problem as to the calculation of the conductivity of the sample’s material at the considered frequencies. To investigate the applicability of the method, demonstrative experiments are performed during which the micro-Doppler effect is used to increase the measurement accuracy. The idea is extended to the case of anisotropic samples, with slight modifications proposed to the experimental setup in the case of significant anisotropy in the investigated material.
Practical implications
The measurement method may prove useful for the investigation of the high-frequency conductive properties of certain materials of interest.
Originality/value
To the best of the authors’ knowledge, this is the first time the use of the micro-Doppler effect is proposed for the purpose of the measurement of material parameters.