The six-port technique promises to have a major impact on the next generation of automatic network analyzers because complex heterodyne methods may be replaced by simple amplitude detectors. This projection, however, is predicated upon the existence or development of calibration techniques which permit one to conveniently and accurately obtain the parameters which characterize the six-port. This paper describes a number of substantial refinements to a previously described procedure which is based upon the use of sliding terminations.
Glenn F. Engen, "Calibrating the six-port reflectometer by means of sliding terminations," IEEE Transactions on Microwave Theory and Techniques, vol. 26, no. 12, pp. 951-957, December 1978.
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