A Compact Dual-Beam Steering Antenna Array Based on a Simplified Beamforming Network

Dual-beam steering has the advantage of providing extensive and efficient scanning in multitarget environment. However, the existing methods of dual-beam steering antenna arrays are generally large or complex in structure. Therefore, this communication proposes a simplified beamforming network based on the theoretical analysis on a Hadamard matrix. The proposed beamforming network was constructed using a simplified topology, consisting of three 0°/180° couplers and four p-i-n diodes. For verification, a dual-beam steering antenna array at 2.4 GHz was designed, fabricated, and measured. Both simulated and measured results agree well with each other. The size of the fabricated network is
$0.70\,\,\lambda \text{g}\,\,\times 0.93\,\,\lambda \text{g}$
, which is only 20.3% of the size occupied by a traditional Hadamard matrix. At the center frequency, the implemented antenna array realizes steering angles of 0°, ±19°, ±31°, and ±51°, demonstrating good dual-beam steering properties.