US Patent 9331392 Tapered slot antenna with a curved ground plane

An apparatus includes an antenna element and a curved ground plane positioned beneath the antenna element. The antenna element has a height h and a first end with a tapered width, where h is approximately equal to the distance of a width-wise cross-sectional curve of the curved ground plane. The width of the curved ground plane is less than or equal to ½ h. A load may be positioned on top of a second end of the antenna element. The second end of the antenna element has a thickness greater than the first end and less than a thickness of the load. The curved ground plane may be substantially hemispherical in shape or may have a tapered height and increase in width from a first end to a second end.