Design of a beam scanning metamaterial antenna with polarization transform for high‐power microwave application

Abstract An all‐metal beam scanning metamaterial antenna with polarization transform based on the concept of Risley prism is presented in this paper. The antenna is composed of a feed source and three different all‐metal metamaterial lenses. Each lens consists of numerous cross‐slot metamaterial elements. A full transmission phase range of 360° can be achieved for a transmission efficiency over 99% at 14.25 GHz by rotating the cross‐slot on the element. Mechanically rotating the three lenses along the same axis can steer the radiation beam in both azimuth and elevation planes. The simulation results agree well with the theoretical analysis which indicates that the metamaterial antenna can realize a beam scanning range of 120° revolving cone angle with the side lobe better than −13 dB. During the scanning, the directivity of the antenna varies from 34.82 dBi to 37.84 dBi, with the aperture efficiency in the range of 38%‐76%. For the radiated circular polarized (CP) plane wave beam, the beam width remains below 4° and the axial ratio is basically better than −5 dB. Furthermore, the power handling capacity of the metamaterial antenna in this paper is gigawatt (GW) class, which can be applied in the field of high‐power microwave (HPM).