Patent attributes
An antenna (10) having outer and inner sections (12, 14) of electrically conductive material and coaxial with a longitudinal axis (19). The outer section includes an outer side wall (22) extending from the bottom to join an outer top wall at the top of the antenna. The inner section includes an inner side wall extending upward from the bottom to join an inner top wall. The outer and inner sections define an interior region (32) filled with dielectric material. The outer section has at least one slotted opening (34) with opposed ends, wherein each such slotted opening extends from one end in the outer side wall, across the outer top wall, and to the opposed end in the outer side wall. The inner section including at least one feed (36) to convey electromagnetic energy into or out of said interior region of the antenna.