Analysis of the radiation from multiple circumferential slots on a conducting circular cylinder

Abstract

Electromagnetic wave radiation from narrow circumferential slots on a conducting circular cylinder is theoretically investigated and rigorous analytic formulations are derived. The Green``s function is used to evaluate electromagnetic wave scattering from delta electric point sources in a conducting circular waveguide and theoretical analysis is performed using the electric and magnetic vector potentials for field representations. The scattered fields are represented in terms of discrete and continuous modes based on the eigenfunction expansion, and Fourier transform. The boundary conditions are enforced to obtain a set of simultaneous equations for discrete modal coefficients. The residue calculus is applied to transform the scattered-field integral representations into fast-converging series forms,thereby facilitating the numerical computations. Numerical computations illustrate the behavior of radiation in terms of the slot geometry,the operating frequency, and point source`` position. Our theoretical model for radiation from multiple circumferential slots is useful for the analysis and design of circumferential slot array antennas using a conducting circular cylinder.