Wideband and low-loss waveguides of nonuniform cross-section

ABSTRACT Waveguides of nonuniform cross‐section are introduced, analyzed and then their cross‐section is optimized to reach wideband and low‐loss waveguides. The waveguide cross‐section is defined as a Fourier series whose unknown coefficients are optimized using genetic algorithm to reach a proper cross‐section for waveguide. A verified finite difference method is used in analysis stage of optimization. The results show that optimum designed nonuniform cross‐section waveguides have lower conductor attenuation constant in comparison with double ridged waveguides of the same bandwidth. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:115–121, 2015.