$\mathrm{S}_{11}$ Calibration of a Coaxial-Loaded-Type Stepped Cut-Off Circular Waveguide with SOM Termination

Abstract

A novel jig structure for $\boldsymbol{S}_{11}$ calibration with short/open terminations and one reference material (referred to here as SOM) in dielectric measurement of liquids using a coaxial feed type cut-off circular waveguide was examined, and a formula for exact calculation of $\boldsymbol{s}_{11}$ for the analytical model of the structure using the method of moments (MoM) was derived. The accuracy and validity of $\boldsymbol{S}_{11}$ values calculated using the relevant formula was verified for frequencies of 0.50, 1.5 and 3.0 GHz, and $\boldsymbol{S}_{11}$ measurement accuracy with each termination condition was verified after calibration with SOM by combining the jig of the proposed structure with the study's electromagnetic (EM) analysis method.