I. Introduction
To model high-speed integrated and microwave circuits, macromodeling algorithms are often used to convert the partial differential equations describing distributed components into ordinary differential equations [1] [2] [45]. However, due to the complexity of distributed networks, this results in large system of equations, simulation of which is prohibitively CPU expensive. This problem is further compounded when one considers the typical design process which includes optimization and design space exploration and thus requires repeated simulation of the same problem for different design parameters.