CAD of RF Windows Using Multiobjective Particle Swarm Optimization

In this paper, computer-aided design (CAD) of two types of RF windows, namely, double-disk RF window and pillbox-type RF window, is presented for use in high-power microwave/millimeter-wave sources. The design of double-disk RF window was carried out for 42-GHz band (TE
_0,3
mode) and 170-GHz band (Gaussian mode), while the design of pillbox-type RF window was carried out for 2.856-GHz band. The requirement for the design of RF window is to minimize the reflections with exact matching at desired resonant frequency. In the present approach, a scattering-matrix code was invoked with recently developed particle swarm optimization (PSO) method in order to optimize the geometrical parameters of the window. Multiobjective optimizations using PSO have been used to achieve optimized tradeoff between matching of desired resonant frequency and minimizing the power reflections in the desired band of operation.