This letter introduces a wideband circularly polarized (CP) array antenna for wireless communication application. The array consists of 2 × 2 sequentially rotated symmetric antenna elements and a wideband weakly coupled feed network providing stable 90° phase difference. By using the proposed feed network and introducing the slot coupling feed, the CP array antenna can achieve a wideband CP performance with a low profile of 0.03 λ₀ (at 5.0 GHz). The proposed antenna exhibits the impedance bandwidth (IMBW) of 73.9%, axial ratio bandwidth (ARBW) of 53.6%, and 3-dB gain bandwidth (GBW) of 60% with the peak gain of 10.4 dBi and the maximum efficiency of 82%. The measured results are in good agreement with the simulated results, indicating that a promising application in compact wideband C-band wireless systems.

中文翻译：

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基于弱耦合序贯相馈网络的宽带圆极化阵列天线

这封信介绍了一种用于无线通信应用的宽带圆极化 (CP) 阵列天线。该阵列由 2 × 2 顺序旋转对称天线元件和宽带弱耦合馈电网络组成，提供稳定的 90° 相位差。通过使用所提出的馈电网络并引入缝隙耦合馈电，CP阵列天线可以以0.03 λ ₀的低剖面实现宽带CP性能（在 5.0 GHz）。该天线的阻抗带宽 (IMBW) 为 73.9%，轴比带宽 (ARBW) 为 53.6%，3-dB 增益带宽 (GBW) 为 60%，峰值增益为 10.4 dBi，最大效率为 82% . 测量结果与模拟结果非常吻合，表明它在紧凑型宽带 C 波段无线系统中具有良好的应用前景。