Eigenvalue-S matrix element relations for some common devices with two-fold symmetry using group theory

Linear relations between the S matrix eigenvalues and S matrix entries of symmetrical multi-port networks have frequently been useful for understanding the properties of such networks. Generally, they have only been derived for networks possessing sufficient symmetry to allow the application of methods based on matrix algebra. Some common multi-port devices possess only two-fold symmetry, however. In this paper a technique based on group theory is developed for systematically deriving such relations in cases of limited symmetry as well.