A Multifrequency Reflector Base Station Antenna With Enhanced Beam-Scanning Capabilities for 6G

This letter presents a multifrequency base station antenna with enhanced beam-scanning capabilities for high data rate 6G communication. The antenna consists of a dual-polarized multifrequency feed and a novel dual-cylindrical reflector antenna. Through the rotation of the subreflector, which is illuminated by the feed, the beam can be scanned across a wide angle along the planar cylindrical orientation of the main reflector. This scanning process results in a beam-scanning angle that is roughly twice the rotation angle of the subreflector. The phase center of the reflected beam from the subreflector is designed to coincide with the focal line of the main reflector, enabling 2-D focusing of the beam without loss of the scanning angle. A concise design formula based on the described antenna structure is derived, enabling the entire antenna design to follow a clear design flowchart, which incorporates a rapid method for determining the focal length product and focal point locations using near-field fast Fourier transform. The designed antenna achieves ± 20° beam-scanning coverage at 45 GHz, 100 GHz, and 220 GHz, with a gain exceeding 50 dBi at 220 GHz. Both simulation and experimental results validate the effectiveness of the proposed method.