Presentation Information
[C-2B-20]Feasibility of Effective Conductivity Measurement of Metalized Surface Utilizing Hollow Cylindrical Whispering Gallery Mode Resonator
〇Yosuke Tsuzaki1,2, Jiro Hirokawa1, Takashi Tomura1, Takashi Ohara2 (1. Institute of Science Tokyo, 2. Mitsubishi Electric Corporation)
Keywords:
Whispering gallery mode resonator,Effective conductivity
In recent years, fabrication methods such as resin plating and metal 3D printing have been proposed for hollow waveguide antennas. For their design, it is important to determine the effective conductivity of the metal surface accurately. Conventional resonator-based methods have limitations in obtaining broadband characteristics and high accuracy. Therefore, in this study, targeting frequencies above 50 GHz, we applied the whispering gallery mode (WGM) resonator-based approach, which has conventionally been proposed for dielectric substrates, to metal plate samples. We carried out a fundamental investigation of effective-conductivity measurement using a hollow cylindrical WGM resonator. The investigation used FEM analysis, assuming a resonator with a diameter of 80 mm and a height of 1.5 mm, and focusing on the TMm, 1, 0 mode to examine the dependence of the Q factor on the assigned conductivity. As a result, the electric field was concentrated near the inner wall of the resonator, and clear resonance peaks were obtained for each WGM of azimuthal order m. In addition, the Q factor calculated from S21 agreed well with the eigenvalue-analysis results of the resonator, confirming the possibility that the proposed method can measure effective conductivity at each frequency. In the future, we will investigate a port structure that enables weakly coupled feeding for experimental validation.