This paper presents a circular monopole antenna with uniquely packed quad T-shaped strips etched on FR4 epoxy substrate having material permittivity 4.4, loss tangent 0.02, and thickness 1.6 mm. The 3.5 GHz band is achieved through this arrangement, which has return loss less than −10 dB while maintaining VSWR <2. It provides a peak gain of 2.65 dBi at 3.5 GHz and average gain of 2.52 dBi in the entire operating frequency band. The radiation pattern is almost omnidirectional in E plane and bidirectional in H plane. The proposed antenna has a compact size of 41.25 mm × 30.55 mm. The simulated results of S11 parameters, gain, VSWR, radiation pattern, and efficiency are studied and verified with the measured results of fabricated antenna as well as its equivalent lumped circuit model. Investigation shows that the proposed antenna can be employed for WLAN/WiMAX applications efficiently.

中文翻译：

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用于 WLAN/WiMAX 应用的具有独特封装的四 T 形条的圆形单极天线

本文介绍了一种圆形单极天线，该天线具有独特封装的四 T 形条带，蚀刻在 FR4 环氧树脂基板上，材料介电常数为 4.4，损耗角正切为 0.02，厚度为 1.6 mm。3.5 GHz 频段是通过这种布置实现的，其回波损耗小于 -10 dB，同时保持 VSWR <2。它在 3.5 GHz 时提供 2.65 dBi 的峰值增益，在整个工作频带内提供 2.52 dBi 的平均增益。辐射方向图在 E 平面几乎是全向的，在 H 平面是双向的。建议的天线具有 41.25 mm × 30.55 mm 的紧凑尺寸。对S11参数、增益、驻波比、辐射方向图和效率的仿真结果进行了研究和验证，并结合所制作天线的实测结果及其等效集总电路模型进行了验证。