ELECTROMAGNETIC SCATTERING FROM IMPEDANCE ELLIPTIC CYLINDERS USING FINITE-DIFFERENCE METHOD (OBLIQUE-INCIDENCE)

The electromagnetic scattering from elliptic impedance cylinders illum inated by an obliquely incident plane wave is presented. The finite di fference technique is used to solve this problem. Impedance Boundary C ondition (IBC) is enforced on the cylinder surface and an Absorbing Bo undary Condition (ABC) is applied on the outer boundary. Between the c ylinder surface boundary and the outer boundary, the wave equation is solved with the finite difference technique to obtain the scattered fi eld. Two methods are used to solve this problem and comparison between both methods is used to verify the solution. One method is based on t ransforming the elliptic cylinder into circular cylinder in polar coor dinates. The other method is the direct implementation of the finite d ifference method in the elliptic coordinates. Consequently, proper tra nsformation of IBC, ABC and wave equation is used. The solution obtain ed from both methods are found to be in good agreement with each other .