Swarm optimization of raised cosine non-linear cylindrical waveguide taper for high-power applications

Abstract

A non-linear cylindrical waveguide taper with given end diameter and length is designed for a raised cosine shape profile.Nonlinear taper has been analyzed for the transmission and reflection coefficient using mode matching technique.This taper design has been optimized further using artificial neural network technique for the maximum power transmission and minimum mode conversion in the desired mode of operation and operating frequency.Scattering parameters are calculated in terms of design parameters of taper and then the optimized for both the transmission (S21) and reflection (S11) coefficients using particle swarm optimization technique for best fitness value, which is found to be > 97% and < 2%, respectively in a typical design case of TE03 mode cylindrical waveguide taper with modified raised cosine shape profile.Final optimized nonlinear taper has been also simulated using commercial simulation code ̀CST Microwave Studio'.Simulated values for the reflection and transmission coefficients for the optimum design have been found in close agreement with the analytical results.