A Modified Stripline Resonator for High‐Frequency Characterization of Dielectric Substrate Materials

This letter presents a novel stripline resonator (SR) that can be used for high‐frequency characterization of dielectric substrates, which is excited at the center of the upper and lower metal grounds by using coaxial probes. The proposed resonator is studied using simulation software as well as experiments. The main advantages of the improved stripline resonator are that it makes coupling tuning more efficient and easier, allows fast and accurate testing of different materials without prior consideration of impedance or size matching, and reduces the influence of edge effects of conventional coupling structures. This resonator is used to measure two well‐known commercial substrates in the frequency range from 2 to 27 GHz, and the results are in good agreement with the reference data, suggesting that the proposed methods can perform broadband and high‐accuracy measurements of the complex permittivity for the substrates.