A Wideband Half-Circle Metasurface Augmented Luneburg Lens for Millimeter-Wave Applications

This paper presents a method for the design of a wideband two-dimensional (2D) metasurface Luneburg lens antenna optimized for millimeter-wave (mmWave) applications. The metasurface, with overall dimensions of 12 × 200 mm, operates in a reflective mode and consists of an 80-element array of Phoenix unit cells. We demonstrated that the 2D metasurface Luneburg lens antenna can steer the radiated beam with a wideband performance of 24-38 GHz. It is shown that the steering angle can be controlled to a desired direction within an angular range of 75°, contingent on the distribution of phasing elements and the position of the feeding source. In specific cases, we demonstrate beam-steering towards 0°, 30°, and 45°, achieved when the feeding source is oriented at −15 degrees as well as towards 0°, 15°, and 45° achieved when the feeding source is oriented at –30°.