Genetic algorithm based CAD of microwave waveguide filters with resonating bend

An accurate and efficient CAD tool is presented and aims at designing evanescent mode waveguide filters with resonating mode in the uniform bend. It arises from mode-matching method suited in this case to the bend of a waveguide. The scattering parameters of the whole structure are computed and compared to those of experimental prototypes. The innovation rests in a specific propagation property of resonating modes in the bend allowing replacing the usual dielectric inserts. An optimization based on a modified genetic algorithm is added to this CAD tool for improving the design efficiency. The calculations exhibit good convergence behavior with the required specifications.