A Triple-band Multiple-Input-Multiple-Output (MIMO) antenna for 5G mobile terminal applications is proposed in this paper. The design comprises four-port/two resonators, each having two concentric circular slot ring radiators etched on a ground plane of size 50 mm ×${\times}$ 50 mm. The antenna is fed by perpendicularly arranged 50 Ω microstrip line feeds on the top layer. Decoupling techniques were used to suppress mutual coupling between the two resonators. The perpendicular arrangement of the feed lines and port reduces mutual coupling between the two ports and increases isolation. The antenna operates in multiple bands: 3.35–3.69 GHz, 24–28 GHz, and 37–40 GHz frequency range with central frequencies at 3.5 GHz, 26 GHz, and 38 GHz, respectively allocated for 5G. The antenna provides a gain of 2.7–7.8 dB and a radiation efficiency of 0.49–0.85 in the operating bands. Diversity performance is studied in terms of the Envelop Correlation Coefficient (ECC), Diversity Gain (DG), and Total Active Reflection Coefficient (TARC) were found to be less than 0.01, greater than 9.99 dB, and less than −10 dB respectively. The proposed antenna offers good S-parameters, voltage standing wave ratio (VSWR), TARC, radiation pattern, high gain, and low ECC. The antenna was fabricated and tested. The measured results and simulated results are in good agreement. It possesses sufficient potential for 5G mobile terminal and smart wearable applications.

中文翻译：

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适用于5G应用的双环形缝隙环形三频MIMO天线

本文提出了一种适用于5G移动终端应用的三频多输入多输出（MIMO）天线。该设计包括四端口/两个谐振器，每个谐振器均具有两个同心圆槽环形辐射器，辐射体蚀刻在尺寸为50 mm×50毫米的接地板上。天线由顶层上垂直排列的50Ω微带线馈线馈电。去耦技术用于抑制两个谐振器之间的相互耦合。馈线和端口的垂直排列减少了两个端口之间的相互耦合，并增加了隔离度。天线工作在多个频带：3.35-3.69 GHz，24-28 GHz和37-40 GHz频率范围，中心频率分别分配给5G的3.5 GHz，26 GHz和38 GHz。该天线的增益为2.7–7.8 dB，辐射效率为0.49–0。在工作频段中为85。从包络相关系数（ECC），分集增益（DG）和总有源反射系数（TARC）分别研究了分集性能，分别小于0.01，大于9.99 dB和小于-10 dB。所建议的天线具有良好的S参数，电压驻波比（VSWR），TARC，辐射方向图，高增益和低ECC。天线被制造和测试。测量结果与模拟结果吻合良好。对于5G移动终端和智能可穿戴应用而言，它具有足够的潜力。和分别小于-10 dB。所建议的天线具有良好的S参数，电压驻波比（VSWR），TARC，辐射方向图，高增益和低ECC。天线被制造和测试。测量结果与模拟结果吻合良好。对于5G移动终端和智能可穿戴应用而言，它具有足够的潜力。和分别小于-10 dB。所建议的天线具有良好的S参数，电压驻波比（VSWR），TARC，辐射方向图，高增益和低ECC。天线被制造和测试。测量结果与模拟结果吻合良好。对于5G移动终端和智能可穿戴应用而言，它具有足够的潜力。