Accurate passivity enforcement algorithm for broadband S-parameter macromodels

This paper applies a reliable and efficient algorithm for passivity enforcement of multiport S-parameter macromodels. It minimizes the passivity violations in each iteration step, and converges to a uniformly passive macromodel. The method iteratively updates the residues of the macromodel by means of a simple least-squares fitting procedure. Numerical examples indicate that passive macromodels are obtained at a limited computational cost while preserving a good accuracy.