Broadband measurement of complex permittivity for liquids via the open-ended cut-off waveguide reflection method using a large-bore connector

In this study, the complex permittivity of certain types of liquid were measured using the large-bore-type open-ended circular waveguide reflection method with an N connector. The effectiveness of the proposed approach for measuring a liquid with high permittivity and high loss was also confirmed by comparing the measurement results with those obtained using the SMA connector-type open-ended cut-off circular waveguide reflection method and the open-ended coaxial line reflection method with an SMA connector.