Analysis and design of longitudinally corrugated cylindrical tips for reduced diffraction in the shadow region of a conducting wedge

The mode matching technique is used to formulate the problem of full-wave scattering from longitudinally corrugated cylinders centred at the tip of a conducting wedge. A line source with an impressed electric or a magnetic current is used to excite a cylindrical wave for soft (TM_z) or hard (TE_z) polarisation, respectively. The cylindrical tip has multiple corrugations with or without a dielectric filling. The underlined mode matching formulation is validated for the particular geometries by comparing against a two-dimensional nodal finite-element method. The rigorous mode matching formulation was used in order to develop a code in pursuit of numerous parametric studies for the design of optimum corrugated cylindrical tips that mitigate diffraction in the shadow region. From the parametric analysis performed, it is evident that a carefully designed corrugated cylindrical tip effectively reduces strong diffractions in the shadow region of a conducting wedge.