S-Parameter Based Macro Model of Distributed-Lumped Networks Using Exponentially Decayed Polynomial Function

A Scattering-Parameters (S-Parameters) based macromodel of distributed-lumped networks is presented. The networks can include capacitive cutsets, inductive loops, RLC meshes, and lossy transmission lines. An efficient network reduction algorithm is developed to reduce the original network into a network containing one multiport component together with the sources and loads of interest. The S-Parameters of the circuit components are approximated by Taylor series to simplify the reduction process. Exponentially Decayed Polynomial Function (EDPF) approximation is used to derive the macromodel, the higher accuracy can be obtained by selecting time constant according to an error criterion. The macromodel is always stable for a stable system and very flexible that the accuracy of the model can be controlled by adjusting the order of approximation. The experimental results indicate that our model can approach the accuracy of SPICE with one or two order less computing time.