2026-10-05
Microwave Measurements of Complex Permittivity by a Cylindrical Dielectric Resonator in a Closed Metal Cavity - A Further Analysis
By
Progress In Electromagnetics Research M, Vol. 140, 66-73, 2026
Abstract
This paper describes various aspects of the analysis of a technique for measuring the dielectric constant and loss tangent using a cylindrical dielectric resonator in a closed metal cavity. The resonator's TE01δ resonant mode mode was selected as the measurement target. The clear electric and magnetic field patterns inside the dielectric resonator are provided from a theory derived by improving a very simple field model. Resonant frequencies under different dielectric constants are studied. All the possible sources of the conducting dissipation are investigated to improve the accuracy of the loss tangent measurement. The influence of the energy storage factor on the calculation of loss tangent measurement is investigated, too. This cavity is also used for measuring complex permittivity over a sweeping frequency range, and the accuracy as well as the limitations of its swept-frequency capability are discussed. The improved field model is compared with the primitive one through experimental measurements.
Citation
Jyh Sheen, and Zuo-Wen Hong, "Microwave Measurements of Complex Permittivity by a Cylindrical Dielectric Resonator in a Closed Metal Cavity - A Further Analysis," Progress In Electromagnetics Research M, Vol. 140, 66-73, 2026.
doi:10.2528/PIERM26072604
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