A Highly Integrated Low Sidelobe Non‐Standard Waveguide Antenna Array With High‐Efficiency Sum and Difference Beamforming

This article presents a highly integrated low‐sidelobe non‐standard waveguide antenna array with high‐efficiency sum and difference beamforming designed for detecting low, slow, and small (LSS) targets. The low sidelobe is achieved through the particle swarm optimization algorithm. A prototype antenna array is fabricated and measured, showing that the bandwidth (S 11 −10 dB) is more than 4.2%. The measured results show that the gain of the antenna array ranges from 32.25 to 32.7 dB across the operating band, and the overall efficiency of the feed system exceeds 65%. It enables beam scanning over a 0° to 16° range in the V‐plane over the operating band. This compact, highly integrated structure can effectively reduce the weight of the antenna array, making it suitable for portable radars used to scan LSS targets.