一种小型化双低频4T4R基站天线阵列设计方法

A novel two low-band 4T4R base station antenna array

能够支持双低频4T4R的MIMO基站阵列天线已成为目前运营商布网主流,当采用常规设计时,往往造成天线尺寸过大、风载荷过高等问题.在MIMO阵列天线小型化设计时,由于各阵列间距离缩小,电磁耦合急剧上升,导致各天线水平面波束宽度恶化,性能下降严重.针对此问题,提出了一种小型化阵列天线设计方法.采用波束合成技术,利用一种功率比随频率变化的新型不等功分电桥复用一组辐射单元,这样每列天线均可复用一个窄波束宽度单元,再通过该窄波束单元与其他宽波束单元合成理想的水平面波束宽度,提升天线覆盖性能.实测结果表明:采用本文阵列天线设计方法能够得到收敛的水平面波束宽度,范围在56°～68°,同时具有较好的增益和系统隔离度,大幅改善了天线性能.

4T4R MIMO antennas are commonly required by operators at base stations.Existing designs of these antennas exhibit several disadvantages,such as large dimensions,high wind loads,and high costs.Thus,a new compact MIMO antenna design can help overcome these limitations.However,when two low-band 4T4R antennas come to a compact design,the electromagnetic coupling between the two arrays will increase dramatically.This can cause several problems such as ultra-wide horizontal beam width,decrease in gain,and worse inter-system isolation.In this study,a novel antenna array design method is proposed to address this issue.Using hybrid bridges,which have a typical characteristic of different frequency points with different power divides,and horizontal beam-forming technologies,a better horizontal beam width can be achieved in compact two low-band antennas.The experimental results show that,with the proposed design,the two low-band antennas exhibit a 4T4R antenna sexhibita good performance in terms of horizontal beamwidth,gain,and inter-system isolation.