Lens antennas with flat-top radiation patterns: Benchmark of beam shaping techniques at the feed array level and lens shape level

The objective of this paper is to investigate the feasibility of shaping lens radiation patterns without shaping the lens profile as traditionally done. The proposed solution is based on focal array fed lens antennas that consist of standard extended hemispherical integrated lenses illuminated by focal phased sub-arrays. To demonstrate the feasibility of this concept, beam shaping techniques at the lens profile level and feed array level are implemented and compared numerically and experimentally through the design of lenses with flat-top beams at 28 GHz.