Dielectric Measurement of Liquids via the Cut-off Waveguide Adapted Rectangular Waveguide Reflection Method

Abstract

The author proposes a method for dielectric measurement of a liquid using the open-ended cut-off waveguide loaded rectangular waveguide with rectangular dielectric plug technique. For this purpose, the mode-matching technique (MMT) was applied for exact calculation of the analytical model. Moreover, this method has the advantage of eliminating errors caused by jig removal because it is wholly unnecessary to remove the measurement system when calibration and measurement are performed. The complex permittivity of certain types of high-loss liquid materials was actually measured in the 3 GHz band as a fundamental study. The effectiveness of the presented method of measuring a liquid phantom with high permittivity and high loss was also confirmed by comparing the results of measurement with those obtained using the TM010 circular cavity resonator method.