Analysis of Electromagnetic Scattering By Infinite Conducting Cylinders of Arbitrary Smooth Cross Section Using a Genetically Optimised Technique (Ga/Mas)

The utilisation of elemental auxiliary sources located inside the scatterer in order to approximately describe the scattered field has proved to be an efficient numerical method for the analysis of electromagnetic (EM) scattering by metallic bodies. In this paper the problem of TM scattering by perfectly conducting cylinders of arbitrary but smooth cross section is treated with the integration of the above technique with the strategy of Genetic Algorithm (GA) optimisation. The GA is employed in order to allocate the auxiliary sources inside the scatterer and minimise the boundary condition error (BCE), which is an endogenous effect of the point matching procedure involved in the numerical solution. For such a case, the trial and error stage usually required for the selection of the source locations is omitted and at the same time GA stochastic search can be potentially conducted in a similar way in complex space. For a predefined accuracy of the BCE, the resulting pleiotropic, GA-optimised allocations of the sources are non-intuitive but notably affected by the geometry of the scatterer. Results are presented for the cases of infinite, perfectly conducting circular, elliptic, and periodically corrugated cylinders, demonstrating sufficient agreement with available solutions.