Dk and Df Characterization of Low-loss Dielectric Liquid by Cylindrical Cavity Resonator

A novel cylindrical cavity resonator-based measurement method was developed to characterize the dielectric property of the low-loss dielectric liquid in the paper. The proposed method can be used to accurately measure the dielectric constant (Dk) and the loss tangent (Df) of the low-loss coolant for signal integrity analysis. The cylindrical cavity resonator works at tangential magnetic (TM010) mode is used in the paper to demonstrate the proposed method. A cylindrical cavity resonator apparatus was designed and investigated using full-wave simulations at first. The relative error of Dk and Df extractions based on the designed apparatus are less than 1% and 5% from simulation results, respectively. In addition, the designed apparatus was manufactured to verify the proposed method through measurements. Measurements demonstrate the high accuracy and repeatability of the proposed method for low-loss dielectric liquid characterization. The measurement uncertainty for Dk could be less than 1%.