In this article, a multiband fractal antenna loaded with parasitic elements for gain enhancement is reported. The proposed radiator has a nested hexagonal loop with an opening at the top. The three hexagonal open loops with a small hexagonal radiator at the center, is fed with a microstrip line. The proposed design composed of parasitic elements to enhance the gain of the antenna. By loading two parasitic elements in the opening of the antenna, gain performance improved by 2 dB at each resonant frequency which are 2.07, 3.73, and 4.96 GHz. The proposed antenna is covering an impedance matching less than −10 dB in the frequency bands of (1.96‐2.22) GHz, (3.51‐3.91) GHz, and (4.78‐5.26) GHz which are supported for LTE, 5G and WLAN applications. An omnidirectional radiation pattern in both E‐plane and H‐plane at all three resonant frequencies is observed. The overall size of the fabricated antenna has a dimension of 37 mm × 28 mm × 1.6 mm, which is fabricated on FR‐4 laminate. A very high correlation is observed between the simulated and measured characteristics.

中文翻译：

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加载有寄生元件的多频带分形天线以提高增益

在本文中，报道了一种带有寄生元件的多频带分形天线，用于增强增益。所提出的散热器具有嵌套的六边形环，该六边形环在顶部具有开口。三个带微型六角形辐射器的六边形开环被送入微带线。所提出的设计由寄生元件组成，以增强天线的增益。通过在天线的开口中装入两个寄生元件，在每个谐振频率为2.07、3.73和4.96 GHz的情况下，增益性能提高了2 dB。拟议中的天线在（1.96-2.22）GHz，（3.51-3.91）GHz和（4.78-5.26）GHz频段覆盖的阻抗匹配小于-10 dB，这些频段受LTE，5G和WLAN应用支持。在所有三个谐振频率下，在E平面和H平面上均观察到全向辐射方向图。制成天线的整体尺寸为37 mm×28 mm×1.6 mm，是在FR-4层压板上制成的。在仿真特性和测量特性之间观察到非常高的相关性。