Low-Profile and Wider-Angle Beam Tilting Parasitic Array Resonator Antenna with Optimized Deflected Ground Plane on FR-4 Substrate

• Published in: Micromachines (Basel) 2023-04, Vol.14 (4), p.834
• Main Authors: Mohd Zainudin, Nur Ain Fatihah, Osman, Mohamed Nasrun, Sabapathy, Thennarasan, Jusoh, Muzammil, Mohd Yasin, Mohd Najib, A Rahim, Mohamad Kamal
• Format: Article
• Language: English
• Subjects: Antenna arrays; Antenna radiation patterns; Antennas; Antennas (Electronics); Beam steering; beam tilting; deflected ground plane; Design; Diodes; Driven elements (antennas); Ground plane; Network switches; Optimization; Parasitic elements (antennas); parasitic patch; pattern reconfigurable antenna; Radiation; RF switches; Sensors; Substrates; Switches; Wireless sensor networks
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi14040834

A low-profile and wide-angle radiation pattern reconfigurable antenna is designed, analyzed, and fabricated for wireless sensor network (WSN) applications, which operate at a 2.5-GHz frequency. This work aims to minimize the number of switches and optimize the parasitic size and ground plane to achieve a steering angle of more than 30° using a low cost-high loss FR-4 substrate. The radiation pattern reconfigurability is achieved by introducing four parasitic elements surrounding a driven element. In this work, the single driven element is fed by a coaxial feed, while other parasitic elements are integrated with the RF switches on the FR-4 as the substrate with dimensions of 150 × 100 mm (1.67 × 2.5 λ ). The RF switches of the parasitic elements are surface mounted on the substrate. By truncating and modifying the ground plane, the beam steering can be achieved at more than 30° on the xz plane. Additionally, the proposed antenna can attain an average tilt angle of more than 10° on the yz plane. The antenna is also capable of attaining other important results, such as a fractional bandwidth of 4% at 2.5 GHz and an average gain of 2.3 dBi for all configurations. By adopting the ON/OFF condition on the embedded RF switches, the beam steering can be controlled at a certain angle, thus increasing the tilting angle of the wireless sensor networks. With such a good performance, the proposed antenna has high potential to serve as a base station in WSN applications.