A Compact Full 90° Cone-Metric-Space Beam-Scanning Antenna Array Using Resonant-Type Phase-Shifters

A compact and cost-effective antenna array that enables a 2-D full 90° cone-metric-space beam-scanning is designed in this article. To achieve this unique function, a resonant-type phase-shifter, which is characterized by small size and large phase-shifting ability, is proposed. Primary and secondary feed networks are designed in series configurations, in which resonant-type phase-shifters are periodically inserted. The beam-scanning of this antenna array is solely controlled by frequency in one dimension, while it is controlled by a combination of frequency and resonant-type phase-shifter in the other dimension. A validation is demonstrated by a $6\times12$ antenna array prototype operating from 4.45 to 4.95 GHz. Measurement results indicate a full 360° scanning range in the azimuth plane and a ±45° scanning range in the elevation plane. When the beam is toward the broadside direction, the radiation efficiency is estimated to be around 29%, while measured sidelobe levels (SLLs) are smaller than −19 dB in both E-plane and H-plane. Thanks for the proposed control mechanism of simplified 2-D beam-scanning, this method is considered cost-effective and very suitable to be deployed in low-cost systems.