Geometrical stability criteria for two-port networks in invariant immittance parameters representation

This paper has presented the formulation of geometrical stability criteria for linear two-port networks in immittance parameters representation. The formulation has been carried out in terms of a more convenient set of S-parameter conversion formulas. A general expression of geometrical stability parameter has been obtained which takes the same invariant form for all immittance (z, y, h, g) parameters. Such expression finds more convenience in certain circuit stabilization, equivalent circuit modeling, feedback analysis and three-port network extension. The formulation herein may be extended readily to other criteria involving alternative stability parameters.