Over the past decades, many radome designs to extend the angular scan range of phased-array antennas have been devised by utilizing dielectric materials and metamaterials.More recently, metasurface technology such as planar lenses and beam deflectors have been applied to phased arrays, enabling scan-angle enhancers new belial model to have a low profile.In this work, a physical Huygens’ metasurface (HMS) two-lens system for scan-angle doubling of a phased array is presented.For the HMS unit cells, the wire-loop topology is deployed to achieve high transmission for the required phase-angle shift.
The proposed two-lens system is analyzed by full-wave simulations and experiments.The simulation results demonstrate that the scan angle ngetikin doubles when the incident angle is below 15° in accordance to the design specification.Furthermore, the directivity degradation of the refracted beams by the two-HMS lenses is in good agreement with theory.Finally, a fabricated two-lens system with two $15lambda $ long by $15lambda $ wide metasurface lenses and a $16 imes 16$ -element patch antenna array as a source is experimentally verified at ${mathrm {10 ext {GHz}}}$.
The experimental results are in good agreement with the simulated results by showing angle-doubling performance with ±2° scan errors.