Abstract This research proposes a novel circularly polarized (CP) reconfigurable microstrip loop antenna for 2.4–2.5 GHz advanced wireless communication using two parasitic patches and two PIN diodes. The reconfigurable antenna can alternate between right hand circular polarization (RHCP) and left hand circular polarization (LHCP) at the main beam by manipulating the ON/OFF status of the PIN diodes. Simulations were carried out for the optimal antenna parameters, and an antenna prototype was fabricated and experiments were undertaken. The simulation and measured results are in good agreement. The antenna achieves an impedance bandwidth of 2.4–2.5 GHz and unidirectional radiation pattern with a maximum gain of 5 dBic and 3-dB axial ratio for both RHCP and LHCP. As a result, the proposed reconfigurable antenna could be utilized to improve wireless communication performance. In essence, the novelty of this research lies in the utilization of parasitic patches and shorted PIN diodes to transform linear to circular polarization; and the reconfigurability of polarization between RHCP and LHCP.

中文翻译：

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使用寄生贴片和 PIN 二极管的圆极化可重构微带环形天线

摘要 本研究提出了一种新颖的圆极化 (CP) 可重构微带环形天线，用于使用两个寄生贴片和两个 PIN 二极管的 2.4-2.5 GHz 高级无线通信。通过操纵 PIN 二极管的开/关状态，可重构天线可以在主波束处在右旋圆极化 (RHCP) 和左旋圆极化 (LHCP) 之间交替。对最佳天线参数进行了仿真，并制作了天线原型并进行了实验。仿真结果与实测结果吻合良好。天线实现了 2.4–2.5 GHz 的阻抗带宽和单向辐射图，RHCP 和 LHCP 的最大增益为 5 dBic，轴比为 3 dB。因此，建议的可重构天线可用于提高无线通信性能。本质上，这项研究的新颖之处在于利用寄生贴片和短路的 PIN 二极管将线性极化转换为圆极化；以及 RHCP 和 LHCP 之间极化的可重构性。