In this article, a multielement fully decoupled linearly placed inverted-F antenna (IFA) array is proposed for mobile terminals. A hybrid decoupling method is used to mitigate the mixed types of mutual couplings among the multiple IFAs: introducing multiple decoupling capacitors for the couplings of two back-to-back IFA pairs and T-shaped mode transformers for the remaining couplings. The decoupling capacitors not only decouple the back-to-back IFA pairs but also broaden the impedance bandwidth of each IFA. The T-shaped mode transformer transforms the concerned antenna from an IFA mode into a balanced loop mode, preventing the induced current on the victim IFAs of the face-to-face and back-to-face pairs. One four-element example and one eight-element example are designed and measured to justify the proposed decoupling concept. The measured results of the four-element IFAs show that after decoupling, all the six mutual couplings among the four IFAs are reduced by about 10 dB from 3.3 to 3.8 GHz, with average total efficiencies throughout the band improving from 57% to 72% for IFA 1 and from 47% to 55% for IFA 2. An eight-element IFA array is built utilizing the pattern diversity of two proposed four-element IFA blocks, achieving inter-block isolation of better than 20 dB. And a six-element linear IFA array is also designed to prove the generality of the proposed method.

中文翻译：

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可重构智能表面：简化架构发射机从理论到实现的改进


在本文中，提出了一种用于移动终端的多元件完全解耦线性放置倒F天线（IFA）阵列。采用混合去耦方法来减轻多个IFA之间的混合类型互耦：引入多个去耦电容用于两个背靠背IFA对的耦合，并引入T形模式变压器用于其余耦合。去耦电容器不仅可以对背靠背 IFA 对进行去耦，还可以加宽每个 IFA 的阻抗带宽。 T形模式变压器将相关天线从IFA模式转换为平衡环路模式，防止面对面和背对面对面对的受害IFA上产生感应电流。设计并测量了一个四元件示例和一个八元件示例，以证明所提出的解耦概念的合理性。四元件IFA的测量结果表明，去耦后，从3.3 GHz到3.8 GHz，四个IFA之间的所有六种互耦均降低了约10 dB，整个频段的平均总效率从57％提高到72％ IFA 1 和 IFA 2 从 47% 到 55%。利用两个提出的四元件 IFA 块的模式多样性构建了八元件 IFA 阵列，实现了优于 20 dB 的块间隔离。并设计了六元线性IFA阵列来证明该方法的通用性。