CAD-ORIENTED FULLWAVE EQUIVALENT-CIRCUIT MODELS FOR WAVE-GUIDE COMPONENTS AND CIRCUITS

New multimode equivalent circuit models for single and cascaded E-plan e and H-plane step discontinuities in rectangular waveguides are prese nted. The computer-aided design (CAD)-oriented equivalent circuit mode ls enable rigorous and efficient fullwave analysis of waveguide compon ents and circuits entirely by circuit simulation. The method has been implemented on the microwave circuit simulator Libra and applied to wa veguide structures containing single and cascaded irises and stub disc ontinuities. Comparisons of circuit simulation results for single and cascaded inductive irises as well as a single and three E-plane stubs with the standard mode-matching method show perfect agreement, Results of a Ka-band bandpass filter analysis are in good agreement with a mo de-matching solution that includes the correct edge condition.