Pattern reconfigurable Yagi-Uda antenna with seven switchable beams for WiMAX application

In this paper, a pattern reconfigurable printed Yagi-Uda antenna with linear polarization is presented. The proposed design consists of three parts, including a driving element centered between two other parasitic elements. To achieve pattern reconfigurability, the approach of Yagi-Uda configuration is employed, where the positions of the director and reflector are exchanged using PIN diodes. The proposed antenna employing six PIN diodes is designed to radiate the main beam at seven scanning angles (−60°, −40°, −20°, 0°, 20°, 40°, and 60°). The beam tilt depends on the size of the antenna's partial ground plane. The proposed design is simple in structure realized on a single substrate board of dimensions 75 × 70 mm². The measured peak directivity obtained at various scanning angles is about 6.5 dB. The simulated and measured results are in good agreement. The proposed reconfigurable antenna is suitable for WiMAX applications operating around the frequency of 3.6 GHz.