In this paper, a high gain wideband circularly polarized (CP) microstrip antenna is presented for broadband operation. The proposed structure comprised of a partially grounded printed monopole antenna loaded with a split ring resonator and a metallic reflector. By using the metallic reflector surface underneath the patch radiator results in the reflected waves in the same phase with main lobe radiation, thereby improving the gain and it also acts like a secondary radiator to generate wideband CP behavior in the proposed design. A gain enhancement of 4.3 dBi is achieved in the operating frequency band as compared with the design without a metallic reflector. The maximum gain achieved in the presented method is 8.6 dBic over the entire operating range. The proposed design shows a wideband behavior ranging from 4.30 to 9.10 GHz with the 10-dB impedance bandwidth of 71.64%. In addition, the proposed design yielded a broadside right hand CP radiation with a 3-dB axial ratio bandwidth of 33.88% from 4.98 to 7.01 GHz. The proposed antenna is fabricated and experimental results on reflection coefficient, gain, axial ratio, and radiation patterns concede well with simulation results.

中文翻译：

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一种高增益宽带圆极化微带天线

本文提出了一种用于宽带操作的高增益宽带圆极化 (CP) 微带天线。所提出的结构包括一个部分接地的印刷单极天线，该天线装有一个开口环谐振器和一个金属反射器。通过在贴片辐射器下方使用金属反射器表面，可以使反射波与主瓣辐射同相，从而提高增益，并且它还充当二次辐射器，在所提出的设计中产生宽带 CP 行为。与没有金属反射器的设计相比，工作频段的增益提高了 4.3 dBi。在所提出的方法中实现的最大增益在整个工作范围内为 8.6 dBic。建议的设计显示了从 4.30 到 9 的宽带行为。10 GHz，10 dB 阻抗带宽为 71.64%。此外，所提出的设计在 4.98 至 7.01 GHz 范围内产生了具有 3-dB 轴比带宽为 33.88% 的宽边右手 CP 辐射。所提出的天线已制作完成，反射系数、增益、轴比和辐射方向图的实验结果与仿真结果吻合良好。