Full-Wave Scattering From a Grooved Cylinder-Tipped Conducting Wedge

The problem of full-wave electromagnetic scattering from a cylinder-tipped conducting wedge with either a sectoral or annular groove is formulated using the mode-matching technique. The mode expansion of the sector involves ratios of Bessel functions with large order as the order is inversely proportional to the inner angle of the sector. An asymptotic expansion of Bessel functions with large orders is introduced in order to overcome the numerical difficulty involved using a regular series expansion. Numerical results indicate good agreement with data obtained using the finite element method (FEM).