An Efficient SPICE-Compatible Cavity Resonant Model for Microstrip Lines

A SPICE-compatible cavity resonant transmission line (CTL) model for a single-ended microstrip line is first presented by reducing 2-D cavity resonator to 1-D cavity resonator. This model has low efficiency since it consists of infinite higher-order components included inductors, capacitors, resistors, and ideal transformers. A modified CTL model is developed by using a fast algorithm to improve the simulation efficiency, which results in an accurate SPICE model in finite elements. Because the improved cavity resonant model uses higher-order (a little more complicated) elements in finite components, it has high efficiency in the time and frequency domain simulation. The model accuracy and simulation efficiency are validated by comparison with multiconductor transmission line and matrix rational approximation modeled methods.