Determination of the Complex Permittivity of High Loss Liquids with a Novel Reentrant Cavity

In this paper a novel cell designed to measure the complex permittivity of high loss liquids is proposed. The cell consists of a reentrant cavity with insertion hole where the liquid can be poured easily because of the large diameter of the holder, unlike those of the literature. The high quality factor of the cavity provides accurate results for high loss liquids. The theoretical model is based on a full-wave modal analysis, which combines mode-matching technique and circuit analysis. Results show comparisons between simulations and measurements, which are in good agreement. Finally, the complex permittivity of some calibration liquids is obtained accurately using this technique.