Design of Wideband High-Gain Segmented Luneburg Lens Antenna

This paper proposes a design of a spherical dielectric lens composed of several generalized Luneburg lenses with different focal lengths segmented together. The focal length of the outer layer of the segmented lens is small, and the focal length of the inner layer is large. Even if the feed radiation pattern is narrow, the radiation can still illuminate most of the segmented lens area. Compared to standard Luneburg lenses of the same size, the designed lens maintains higher aperture efficiency over a wide bandwidth. Assuming negligible insertion loss, the lens achieves aperture efficiencies ranging from 52% to 85% across the 6–12 GHz frequency band.