From the indefinite-impedance and scattering matrices to the port-based indefinite-scattering matrix

The authors develop the concept of the indefinite S-matrix and, in particular the port-based indefinite S-matrix, which corresponds to the low-frequency indefinite-impedance matrix and which is the dual of the terminal-based indefinite S-matrix. Fundamental relationships between this matrix and the indefinite-impedance matrix are presented. Its fundamental property and conversion relationships between the various normal S-matrices of the same network are examined. These derivations are all based on the complex-frequency plane. Finally, applications are discussed in microwave parallel feedback design, in performance comparison between various configuration, and in S-parameter measurement.<>