Calibration and Vector Error Correction

The vector network analyzer (VNA) error correction process consists of two steps: the first step, typically called calibration or VNA-cal, is to characterize known standards, such as an open/short/load, to determine the systematic VNA error terms. The second step is measuring the DUT and applying the error correction algorithms to obtain a corrected result. Correction of systematic errors of S-parameter measurements in VNAs has been available for decades; the details of how the systematic errors affect the measurement results of a two-port S-parameter measurement are presented. In general, there are two distinct calibration methodologies based on either the 12-term error model, or the eight-term error model. The effects of the real-world conditions are discussed in this chapter. Some of the errors are random errors, such as noise, stability and connector repeatability, which must be treated in a statistical manner. Controlled Vocabulary Terms error correction codes; network analysers; S-parameters