A wide band log periodic millimeter-wave antenna is proposed for 5G femtocells applications. This log periodic antenna consists of circular patches with radius kept up at a proportion of scaling factor . The proposed antenna prototype is designed and simulated at a frequency range of 25 to 35.5 GHz with a fractional bandwidth of 34.73%. This proposed antenna exhibits low return loss at all frequency bands such as 26, 27.5, 29, 30, 32, 33, 35, and 38.1 GHz with reflection coefficient values such as , and dB including almost 101% radiation efficiency and attained maximum gain values such as , and dBi. Over the entire frequency band, the proposed antenna exhibits right-hand circular polarization with an axial ratio of under 3 dB. Furthermore, the antenna is fabricated and measured the results where there is a better agreement with simulated results. This type of low-profile antenna can be applicable for femto base stations for 5G communications.

中文翻译：

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用于 5G 毫微微蜂窝应用的宽带对数周期毫米波天线

为 5G 毫微微蜂窝应用提出了一种宽带对数周期毫米波天线。这个对数周期天线由圆形贴片组成，半径保持在比例因子。建议的天线原型在 25 至 35.5 GHz 的频率范围内进行设计和仿真，部分带宽为 34.73%。这种提议的天线在所有频段（例如 26、27.5、29、30、32、33、35 和 38.1 GHz）均表现出低回波损耗，反射系数值如和dB 包括几乎 101% 的辐射效率并获得最大增益值例如，和分贝。在整个频带上，所提出的天线呈现出轴比低于 3 dB 的右旋圆极化。此外，制造天线并测量结果与模拟结果有更好的一致性。这种类型的低剖面天线可适用于 5G 通信的毫微微基站。