A low-profile microstrip patch antenna (MPA) with wide bandwidth, wide beamwidth, and reduced cross-polarisation is proposed here. Firstly, the far-zone radiated fields of the MPA are deeply studied to improve its radiation performance. It demonstrates that the E -plane half-power beamwidth (HPBW) of the antenna could be progressively widened by using a single equivalent slot instead of two equivalent slots. Meanwhile, its high cross-polarisation of the H -plane radiation patterns could be successfully decreased down by enlarging the width of the rectangular patch and loading the shorting pins. Secondly, the input impedance of the MPA operating in the fundamental mode is extensively investigated. The results illustrate that the resonant frequencies of its dual modes could be reallocated in proximity to each other for bandwidth enhancement by properly selecting the dimension of radiating patches. Finally, the proposed antenna is fabricated and tested. Experimental results show that the antenna has gained an improved bandwidth (| S ₁₁ |<;-10 dB) of about 12% ranging from 2.70 to 3.03 GHz, while keeping a thin thickness of about 0.029 free-space wavelength. Besides, its H -plane cross-polarisation is kept below -20 dB. Most importantly, the E -plane HPBW of the antenna is extended to around 140° over the wide band.

中文翻译：

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薄型微带贴片天线，在双谐振下具有同时增强的带宽，波束宽度和交叉极化

本文提出了一种低轮廓的微带贴片天线（MPA），该天线具有较宽的带宽，较宽的波束宽度和减小的交叉极化。首先，对MPA的远区辐射场进行了深入研究，以提高其辐射性能。它表明， 可以通过使用单个等效时隙而不是两个等效时隙来逐步扩大天线的E平面半功率波束宽度（HPBW）。同时，其H的高交叉极化 通过扩大矩形贴片的宽度并装入短路销，可以成功地减小平面辐射图。其次，广泛研究了在基本模式下工作的MPA的输入阻抗。的结果说明它的双模式的谐振频率可以在接近通过适当地选择发射导体板的尺寸被重新分配给彼此带宽增强。最后，所提出的天线被制造和测试。实验结果表明，该天线 在2.70至3.03 GHz范围内获得了约12％的改进带宽（| S ₁₁ | <;-10 dB），同时保持了约0.029自由空间波长的薄厚度。此外，它的H 平面交叉极化保持在-20 dB以下。最重要的 是，天线的E平面HPBW在宽带范围内扩展到大约140°。