A four-beam switchable cascaded cavity antenna loaded with bifunctional slots

A cavity-cascaded antenna loaded with bifunctional slots and featuring four reconfigurable beams is proposed in this work. First, a compact trapezoidal cavity-cascaded antenna is realized using metallic vias. Then, three U-shaped slots are ingeniously etched onto the patch, serving the dual purposes of notch filtering and phase alteration, enhancing the antenna’s operational flexibility. Finally, diodes are loaded at the slot openings to realize the reconfigurable bifunctional slotas, and by controlling their operational states, the field distribution is regulated, resulting in four distinct directional radiation modes. A prototype capable of covering the WiFi 5.8-GHz band (5.725–5.85 GHz) was fabricated and tested. The experimental results reveal that the proposed antenna achieves a peak gain exceeding 8.65 dBi and a radiation efficiency above 88% within the operating frequency band. It is worth noting that, this antenna design distinguishes itself from existing pattern-reconfigurable antennas by its simplified structure and gteat functionality, driven by the innovative use of reconfigurable bifunctional slots.