Abstract: A broad-band monopole antenna for high voltage environments is provided. The monopole antenna includes a ground plane, a plurality of flat radiator elements and an electrical conductor. The ground plane has a flat upper surface, a lower surface, a smoothly-radiused outer edge and a hole centrally disposed through the upper and lower surfaces. Each flat radiator element has a thickness, a straight inner edge and a semicircular outer edge. The plurality of flat radiator elements are interconnected along each inner edge and symmetrically arranged about a vertical axis centered on the ground plane hole. The electrical connector extends through the ground plane hole and is coupled to the radiator elements.