Influence of TMSO calibration standards uncertainties on VNA S-parameter measurements

For the widespread, 12-term TMSO calibration of four-sampler vector network analyzers (VNAs), the sensitivity coefficients of the S-parameters of two ports are determined as functions of the deviations of the reflection coefficients of the one-port calibration standards and of an imperfect through connection. The expressions obtained, which have been experimentally verified, are suitable for the establishment of the uncertainty budget.