Microwave Characterization of Low-Loss Solid Dielectric Materials using Rectangular Waveguide

The work of this article is a contribution to the characterization of new materials at microwave frequencies and an enrichment the existing database. The transmission/reflection technique for complex permittivity determination is employed to characterize a set of low-loss dielectric materials. The algorithm for permittivity extraction eliminates mathematically the systematic errors of the experimental setup. This technique needs two uncalibrated scattering parameter measurements by the Vector Network Analyzer; the first is done with a partially filled rectangular waveguide by a standard dielectric Teflon sample (PTFE), and the second is performed with the sample under test. The relative complex permittivity of Delrin, Peek, Spanish Peek, Nylatron, Vulkollan, Arnite and Celotex materials are measured over the X-band frequencies (8.2 - 12.4 GHz), and the average relative errors between the calibrated and uncalibrated results are calculated. As other non-resonant methods, rough results are indicated of the imaginary part of the permittivity for very low-loss samples.