Two applications of algebraic invariants to linear transmission networks

The application of algebraic invariants of linear multivalue
n
-ports is Investigated for the optimization of linear
(2m + n)
-ports transmission networks. As a concrete example the restrictions on the scattering matrix of a linear passive embedding are determined for optimum performance as a phase or amplitude modulator. A sensitivity invariant is presented, which leads to a relation between differential sensitivities and sensitivities for large parameter variations.