In this article, a meander line-shaped pentaband (2.18–2.24, 2.38–2.46, 2.65–2.70, 3.10–3.32, 3.38–3.46 GHz) four-element multiple-input–multiple-output antenna is presented. The proposed antenna is also circularly polarized in two bands (at 2.2 and 2.4 GHz) with dual-polarization like right-handed at port 1 or 3 and left-handed at port 2 or 4, which is widely used for mobile satellite services (MSS) and Internet of Things applications. This antenna is designed and fabricated with compact size 50 × 70 × 1.6 mm3 on the FR-4 substrate with good diversity performance in pentaband. Simulated results of antenna-like return loss, isolation, and parameters-related diversity have also been tested experimentally in a controlled environment, which is within the permissible limit. The designed antenna will be appropriate for MSS, industrial scientific and medical (ISM), broadband radio services and educational broadband services, WiMAX radio location services, and amateur radio services. Meanwhile, specific absorption rate of the designed antenna has been examined in an empirical environment for the Fresnel radiating near-field applications.

中文翻译：

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用于多种无线应用的四元五频段 MIMO 天线，包括双频段圆极化特性

本文介绍了一种曲折线形五频带（2.18-2.24、2.38-2.46、2.65-2.70、3.10-3.32、3.38-3.46 GHz）四元多输入多输出天线。建议的天线在两个频段（2.2 和 2.4 GHz）中也是圆极化的，具有双极化，例如在端口 1 或 3 为右旋，在端口 2 或 4 为左旋，广泛用于移动卫星服务（MSS ) 和物联网应用。该天线采用紧凑尺寸 50 设计和制造×70×1.6 毫米3在 FR-4 基板上具有良好的五波段分集性能。类似天线的回波损耗、隔离和与参数相关的分集的模拟结果也在受控环境中进行了实验测试，该环境在允许的范围内。设计的天线将适用于 MSS、工业科学和医疗 (ISM)、宽带无线电服务和教育宽带服务、WiMAX 无线电定位服务和业余无线电服务。同时，在菲涅耳辐射近场应用的经验环境中检验了所设计天线的比吸收率。