Coaxial-line driven monopole on an electrically thick conducting cylinder over a ground plane

A coaxial-line-driven monopole mounted on top of an electrically thick conducting cylinder over a ground plane is studied analytically in the paper. Coupled integro-differential equations are formulated for the evaluation of the current distribution on the antenna surface and the electric field in the annular aperture of the coaxial-line feed. Current distributions and input admittances of representative monopole cylinders are presented, and excellent agreement with available measurements is observed. The present method yields good results for large-radius antennas.