A simple evaluation procedure of the TAN calibration and the influence of non-ideal calibration elements on VNA S-parameter measurements

摘要

For the 7-term general TAN (Through-Attenuator-Network)self-calibration method of a four-sampler vector network analyser (VNA), andfor all derived calibration methods like TLN, TRL, TRM, TAR, or TMN, it isshown that a very simple evaluation procedure of the seven error terms ispossible, even if the Through connection is replaced by a reflectionlessnetwork with known transmission. Expressions for the deviations of themeasured S-parameters of two-port test objects (d.u.t.s) from the truevalues, which are caused by deviations of the modeled S-parameters ofnon-ideal calibration elements ("standards") from their true values, arealso presented. Additionally, it is shown that a TAN calibration is alsopossible in case of unequal reflections of the Network.