The effects of air stacked on reconfigurable quadratic slots antenna for WiMAX and 4G applications

This research presents the effects of an air-stacked configuration on the novel reconfigurable quadratic antenna. The proposed antenna is made feasible by using a feeding line, PIN diodes, and an aperture coupled feeding structure with quadratic slots shape and varied levels of air-stacked sequence: 0, 5, 10, 15, and 20 mm. Instead of a quadratic slot, it is proven through simulations and measurements that the performance of four types of radiation patterns is greatly influenced by the air-stacked structure at 2.3 GHz operating frequency. The activation of certain PIN diode switch configuration enables the variety of outcomes of the radiation patterns with different beamwidths and gains at a single time. This novel antenna is competent to shape its radiated beam in terms of gain and half-power beamwidth up to 12.92 dB (˜ 13 dB) and 110.9°, respectively, with 81.76% of efficiency. The air-stacked formation also affords a good quality factor, Q, as low as less than 1 (<1) to indirectly indicate that the quality of the antenna in terms of efficiency and gain is outstanding. The proposed antenna has a massive potential to be deployed in WiMAX application in future.