This article presents the designs of dual‐polarized dual wideband textile‐based two and four elements multiple‐input multiple‐output (MIMO) antennas for WLAN (IEEE 802.11a/b/g/c/n) and WiMAX (IEEE 802.16d) applications. These MIMO antennas cover the frequency spectra from 1.5 to 3.8 GHz (87% bandwidth) and 4.1 to 6.1 GHz (40% bandwidth). The characterization of the textile jeans substrate is determined experimentally using a vector network analyzer and dielectric assessment kit. These antennas provide near about 70% radiation efficiency with around 4 dBi peak gain in desired frequency ranges. The diversity performance is improved noticeably by printing meandered line structures on both planes. The proposed MIMO structure has a very low envelop correlation coefficient (ECC) <0.1 and high diversity gain (DG) >9.9. The Medium effective gain (MEG) also lies within a satisfactory value of ±3 dB. The two elements MIMO Antennas provide linear polarization at all desired frequency band while the four‐element antenna provides circular polarization at 2.4 GHz and linear polarization at 5.2 and 5.8 GHz application bands. The antenna also depicts good performance in wearable condition with safe specific absorption rate < 1.6 W/kg in all desired frequencies.

中文翻译：

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基于双极化纺织品的两/四元素MIMO天线，具有更高的隔离度，可用于双宽带应用

本文介绍了用于WLAN（IEEE 802.11a / b / g / c / n）和WiMAX（IEEE 802.16d）的基于双极化双宽带纺织品的二元和四元多输入多输出（MIMO）天线的设计应用程序。这些MIMO天线覆盖1.5至3.8 GHz（87％带宽）和4.1至6.1 GHz（40％带宽）的频谱。使用矢量网络分析仪和介电评估套件通过实验确定纺织品牛仔裤基材的特性。这些天线在所需的频率范围内提供约70％的辐射效率，峰值增益约为4 dBi。通过在两个平面上印刷曲折线结构，可以显着提高分集性能。所提出的MIMO结构具有非常低的包络相关系数（ECC）＜0.1和很高的分集增益（DG）＞ 9.9。中有效增益（MEG）也位于±3 dB的令人满意的值内。两个元素的MIMO天线在所有所需的频带上提供线性极化，而四个元素的天线在2.4 GHz上提供圆极化，在5.2和5.8 GHz应用频带上提供线性极化。该天线在可穿戴条件下也表现出良好的性能，在所有所需频率下的安全比吸收率均<1.6 W / kg。