VNA tools II: Calibrations involving eigenvalue problems

Many calibration algorithms for vector network analyzers using partially unknown standards can be stated as an eigenvalue problem. The construction of the eigenvalue problem is described and examples for line reflect match (LRM) and thru reflect line (TRL) calibrations are given. Advantages of the new algorithm are that all uncertainties can be taken into account and that it is fully analytic. A further advantage is that the same approach can be used for different calibration schemes. The algorithm is implemented in METAS VNA Tools II and METAS UncLib is used for the linear propagation of uncertainties.