Uncertainty estimation based on the transmission reflection method for measuring the complex permittivity of materials with coaxial airline

This article comprehensively analyzes and evaluates the influence of all sources of uncertainty on the measurement of complex dielectric constants using the coaxial airline-based transmission reflection method. The research results indicate that within the range of (εr' = 1–30, tanδ = 0.01-1), the measurement uncertainty of dielectric constant is 4.87%, and the measurement uncertainty of dielectric loss tangent is 5.17%. Among them, the inner radius of the specimen has the greatest impact on measurement uncertainty, causing measurement uncertainties of 1.30% and 1.33% for the dielectric constant and dielectric loss tangent, respectively.