USE OF 3-DIMENSIONAL FIELD SIMULATORS IN THE SYNTHESIS OF WAVE-GUIDE ROUND ROD BANDPASS-FILTERS

This paper presents the generalized bandpass filter design method of L evy and Rhodes based on three-dimensional (3D) electromagnetic analysi s and discontinuity modeling using commercial software. It shows how t o use Levy and Rhodes's famous method for very accurate theoretical de signs of waveguide post filters, using modern 3D solvers based on the finite element method, the mode matching method, and the transmission line matrix analysis method. This is the first time that design curves and equations are being presented for constant diameter single and do uble round rod filters by full electromagnetic modeling. The approach is demonstrated with designs for a number of waveguide round rod filte rs. This paper also demonstrates the generality of the method. This me thod can be applied to many other types of coupled resonator waveguide band pass filters. (C) 1998 John Wiley & Sons, Inc.