Scattering of a plane electromagnetic wave by a metal-dielectric composite cylinder

The scattering of a plane electromagnetic wave by an infinite circular metal-dielectric cylinder (CMDC) is considered. The metal part of the cylinder is a sector of arbitrary angle of opening. One may use such structures in order to model the properties of a wedge-shaped load, which is frequently used in electromagnetic control applications. Since in some cases the analysis of the experimental data may be not reliable due to the small magnitude of the measured reflection coefficient and relative errors of the measurement equipment, there is a need for a closed-form analysis of the model structures. In the presented study the method of reexpansion in the basis functions at a given interval is used (Smirnov 1957; Shepilko 1979). The resulting field is presented in terms of the Bessel and Hankel functions. Applying the boundary condition to the Fourier series representation of the scattered field, the problem is reduced to the solution of a matrix equation with unknown expansion coefficients, which can be calculated with controlled accuracy. The scattered field is evaluated asymptotically and the backscattering radar cross section (BRCS) expression is derived. Accurate numerical results are presented in the case of E-polarized waves.