# CUBIC-SPLINE EXPANSION FOR A PARTIALLY IMMERSED CONDUCTING CYLINDER ILLUMINATED BY TE WAVES

## Keywords:

cubic-spline, inverse problem, partially immersed, conductor, steady-state genetic algorithm, transverse electric wav## Abstract

This paper presents a computational approach to the imaging of a partially immersed perfectly conducting cylinder. Both cubic-spline method and trigonometric series for shape description are used and compared. A conducting cylinder of unknown shape scatters the incident transverse electric (TE) wave in free space while the scattered field is recorded outside. Based on the boundary condition and the measured scattered field, a set of nonlinear integral equations is derived and the imaging problem is reformulated into an optimization problem. An improved steady-state genetic algorithm is employed to find out the global extreme solution of the object function. It is found that the shape described by Fourier series can be reconstructed by cubic-spline expansion. On the contrary, the shape described by cubic-spline and reconstructed by Fourier series expansion will fail. Numerical results are given to show that the shape description by using cubic-spline method is much better than that by the Fourier series.

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*Journal of Microwaves, Optoelectronics and Electromagnetic Applications (JMOe)*,

*8*(1), 19-32. Retrieved from http://www.jmoe.org/index.php/jmoe/article/view/248