Cylindrical Transmit-Reflect Array for Full Azimuthal Coverage and Elevational Scanning

In this paper, a new cylindrical antenna array that combines the principles of transmit-reflect-array, resonant cavity and phased array is proposed to achieve full azimuth-plane coverage and elevation-plane scanning. The proposed design utilizes reconfigurable transmit-reflect elements to construct a resonant cavity with electrically adjustable radiation windows, enabling dynamic control of the radiation direction in the azimuth plane. Beam scanning in the elevation plane is facilitated by expanding the transmit-reflect elements into elevation-plane arrays. Each element of the proposed design is equipped with a continuous reconfigurable 0-360° phase shifter, implemented by a 0-180° reflection-type continuous phase shifter and a 1-bit reconfigurable phase shifter realized by reversing the feeding direction. The 0-360° continuous phase tuning range is used not only to compensate for path differences due to the curvature of the radiation window for gain enhancement but also to support beam scanning. The proposed design, with the reconfigurable beamforming network embedded within its structure, requires only a single RF port, eliminating the need for additional RF feed systems. A prototype has been fabricated and measured, demonstrating an approximate 14% bandwidth, a maximum gain of 15.5 dBi, complete azimuthal coverage and good elevation-plane scanning from 45° to 135°. The proposed design offers significant advantages, including wide bandwidth, compact size, high gain, cost-effectiveness, and ease of fabrication, making it a promising candidate for modern wireless communications.