This paper presents a systematic and accurate calculation method to design the parasitic decoupling technique (PDT) for increasing antenna isolation in the multiple-element multiple-input multiple-output (M-MIMO) array. The mutual coupling among antennas is suppressed by incorporating the parasitic decoupling structure (PDS) to generate the desired interference against the original antenna coupling. The designed PDS is composed of the parasitic scatterers, transmission lines (TLs), and reactive loads. A general network model is developed to determine the TL lengths and load reactances to satisfy the criteria derived from antenna impedances for high isolation. The decoupling methodology is further verified by two benchmarks. The simulation and measurement results demonstrate that isolation over 25 dB, efficiency above 72%, and envelop correlation coefficient below 0.02 can be achieved for both examples after using the proposed PDT. Besides, the PDT leads to improved pattern diversity, suitable for MIMO applications.

中文翻译：

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一种新的基于计算的寄生去耦技术，用于增加多元素MIMO天线阵列的隔离度

本文提出了一种系统，准确的计算方法，以设计用于提高多元素多输入多输出（M-MIMO）阵列中天线隔离度的寄生去耦技术（PDT）。通过合并寄生去耦结构（PDS）来产生天线干扰，从而抑制了天线之间的相互耦合，从而对原始天线耦合产生了期望的干扰。设计的PDS由寄生散射体，传输线（TL）和电抗性负载组成。开发了一个通用的网络模型来确定TL长度和负载电抗，以满足从天线阻抗得出的高隔离标准。去耦方法已通过两个基准进一步验证。仿真和测量结果表明，隔离度超过25 dB，效率超过72％，使用建议的PDT后，两个示例的包络相关系数都可以达到0.02以下。此外，PDT还可以改善模式多样性，适用于MIMO应用。