Reconstructing scattering matrix of a three-port nonreciprocal network from One-Port measurements

This paper presents a method to reconstruct the scattering matrix (S-matrix) of a three-port nonreciprocal network from thirteen one-port measurements. By using two auxiliary circuits, the off-diagonal elements of the S-matrix of a two-port nonreciprocal network can be solved. The port reduction method is then applied to reconstruct the three-port S-matrix from two-port results. Reconstructed results of a three-port circulator are shown in good agreement with the directly measured results.