A wideband circularly polarized (CP) antenna is presented to achieve enhanced impedance, axial ratio (AR), and gain bandwidths. The antenna consists of two circular patches, a split-ring microstrip line with six probes, and a circular ground plane. By using these six probes which are placed in sequence on the split-ring microstrip line, the operating bandwidth of the proposed antenna is increased. The characteristic mode method is used to analyze different modes of the antenna and reveal the mechanism of extending the 3-dB AR bandwidth. Measured results show that the proposed antenna obtains an impedance bandwidth of 1.486–2.236 GHz (40.3%) for S₁₁ ≤ −18 dB, a 3-dB AR bandwidth of 1.6–2.2 GHz (31.6%), and a boresight gain of 8.89 ± 0.87 dBic.

中文翻译：

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具有特征模式分析的宽带圆极化天线

提出了一种宽带圆极化（CP）天线，以实现增强的阻抗，轴向比率（AR）和增益带宽。天线由两个圆形贴片，带六个探头的开口环微带线和圆形接地平面组成。通过使用按顺序排列在开环微带线上的这六个探针，可以提高所建议天线的工作带宽。特征模式方法用于分析天线的不同模式，并揭示了扩展3-dB AR带宽的机制。测量结果表明，所提出的天线，用于获取1.486-2.236千兆赫（40.3％）的阻抗带宽小号₁₁  ≤-18分贝，1.6-2.2 GHz的（31.6％）的3-dB的AR带宽，以及8.89一个瞄准增益±0.87分贝