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 degrees/180 degrees 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(g) x 0.93 lambda(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 degrees, +/- 19 degrees, +/- 31 degrees, and +/- 51 degrees, demonstrating good dual-beam steering properties.