面向方向图保形的共口径基站天线去耦技术

为了节省基站天线所占空间资源，降低其运营成本，现代移动通信需要将多个天线阵列紧密地排列在一起，构成多频共口径基站天线。多天线的紧密排列势必造成天线间强烈的耦合，不仅使得天线阻抗失配、隔离度变差，同时也造成辐射方向图的严重变形。因此，近年来多频共口径基站天线的去耦成为工业界和学术界研究的热点，早期的去耦技术主要是面向改善天线的阻抗匹配和隔离度，而对面向方向图保形的去耦技术研究相对较少。文章在简要介绍面向方向图保形的基站天线去耦技术的研究现状的基础上，重点阐述了褚庆昕教授天线射频团队基于感应电流抵消、耦合场抵消和辐射阻断等原理，提出的几种新型的去耦技术。这些技术不仅可以有效地改善基站天线的阻抗匹配和隔离，更重要的是很好地实现了天线方向图保形。仿真和测试结果验证了原理的正确性和设计的可行性。一些技术已被用于5G基站天线产品。

Decoupling Techniques for Shared-Aperture Antennas with Restored Radiation Patterns

To save space and reduce operational costs of base station antennas, modern mobile communications require multiple antenna arrays to be densely packed together, forming multi-frequency shared-aperture base station antennas. The close arrangement of multiple antennas inevitably leads to strong coupling between antennas, causing impedance mismatch, reduced isolation, and significant deformation of the radiation patterns. Therefore, the decoupling of multi-frequency shared-aperture base station antennas has become a hot topic in the industry and academia in recent years. Early decoupling techniques mainly focused on improving impedance matching and isolation of antennas, with relatively little research on decoupling techniques aimed at preserving radiation patterns. After briefly introducing the current research status of decoupling techniques for preserving radiation patterns of base station antennas, This paper focuses on several novel decoupling methods proposed by our team based on principles including induced current cancellation, coupling field cancellation, and radiation blocking. These techniques not only effectively improve impedance matching and isolation,but, more importantly, also preserve the antenna radiation patterns effectively. Simulation and measurement results validate the principles and designs. Some techniques have been applied in products of 5G base station antennas.