volume | PIER Journals

Abstract

The scattering problem for an inhomogeneous twodimensional biisotropic cylinder is solved in the frequency-domain by means of a hybrid method, in which finite difference equations in the interior region are combined with a mesh truncation in terms of a boundary integral equation that realizes a global absorbing boundary condition. The influences of the chirality and non-reciprocity parameters on the scattering properties are investigated. Numerical results for the bistatic echo widths are presented and compared with a reference solutions in the circular cases and it is found that the method yields more accurate results than what can be achieved with a local absorbing boundary condition. It is realized that, for a given mesh, the method presented is computationally slower than a method based on a local absorbing boundary condition but in on the other hand the method is much faster than the readily used method of moments. The present method is thus suitable for solving scattering problems involving scatterers of intermediate sizes.

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Dr. Martin Norgren