A Wideband Rotary-Joint-Free H-Plane Horn Antenna With 360° Steerable Radiation Pattern Using Gap Waveguide Technology

Considering the limitations of electronically steerable antennas such as limited steering span, gain degradation for large steering angles, complexity, and cost, this article is focused on the design of a simple mechanically steerable H-plane horn antenna. It is shown that since there is no need for an electrical connection between the top and bottom sections of a gap waveguide (GWG), if a sectoral horn is properly designed and realized using this technology, the pattern of the antenna can be easily steered without a rotary joint. To demonstrate this concept, a rotary-joint-free H-plane horn antenna is designed, and its performance is predicted using EM simulations. The antenna offers a wide operating band covering almost the entire Ku-band and provides a full 360° continuous steering span. Additionally, the proposed antenna benefits from a constant gain over the full range of steering angles. This is in contrast to phased array antennas whose gain degrades when the main beam is steered away from the broadside. The proposed concept and computed characteristics are verified by the good agreement between the simulated and measured characteristics of the fabricated prototype.