Abstract-This paper presents an approach for the design and optimization of pseudo-gradual transitions in circular waveguides using the genetic algorithm (GA). The characterization of these transitions is carried out by the mode-matching method. This method, associated with the generalized scattering matrix technique, leads to determine the reflection coefficient on the useful band of the studied structures and to observe their frequential behavior. The GA is employed to optimize the choice of geometrical parameters by minimizing a cost function, corresponding to the maximum magnitude of the reflection coefficient in the band. The selection of the most relevant parameters allowed an improvement of the performances for the optimized components. Results of optimization are given for both two and four-section transformers.

In this paper, we apply robust optimizers (i. e. the simplex method and the genetic algorithm) to rectangular ridged waveguide filter design. We extend the use of the simplex method to the design of high performance filters in narrower relative bandwidth. The proposed optimization tool is successfully applied to narrower bandwidth of four pole and six pole rectangular ridged waveguide filters. The results outperform those produced by the conventional simplex method and genetic algorithm.

No abstract

No abstract

We propose here a rigorous and simplified formulation for the characterization of the junction between a smooth circular waveguide and a periodic corrugated circular waveguide using a hybridization of the mode matching method with the coupled integral equation technique. The modal basis of the Floquet modes, present in the periodic waveguide, is determined basing on the coupled integral equation technique. The results are compared to those obtained by the conventional mode matching method and the agreement is satisfactory. The dispersion diagrams of corrugated circular waveguides are also plotted and the influence of the radius ratio on the apparition of the complex modes is well shown.