用于5G智能手机的宽带高隔离度MIMO天线  

Broadband High-isolation MIMO Antenna for 5G Smartphone Application

作　　者：姚婷 杨雪霞[1] YAO Ting;YANG Xuexia(School of Communication and Information Engineering,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海大学通信与信息工程学院,上海200444

出　　处：《无线电工程》2024年第1期164-172,共9页Radio Engineering

基　　金：国家自然科学基金(62171270)。

摘　　要：提出了一种用于第五代移动通信(5G)智能手机的紧凑型宽带高隔离度多输入多输出(Multiple-Input Multiple-Output,MIMO)天线对,将其在手机两侧边框内表面对称放置,组成相关性低的8元MIMO阵列。采用耦合馈电方式设计了宽带倒F天线(IFA)单元,以零间距镜像对称的方式组成一个结构紧凑的双单元天线对,其-6 dB阻抗带宽为3.3~6.5 GHz(65.3%),完全覆盖了n77/n78/n79和LTE band 46的5G频段,其尺寸仅为26.8 mm×6 mm(0.29λ0×0.07λ0,λ0为3.3 GHz的自由空间波长)。利用差/共模对消理论及加载分布式电容的方法提高了天线对两端口间隔离度,带内隔离度高于11 dB,在n79和LTE band 46频段(4.4~5.925 GHz)隔离度高于15 dB,且在4.9 GHz中心频点处的峰值隔离度能达到40 dB,在整个带内的天线总效率为59%~88.8%。为了提高8元MIMO阵列隔离度,在相邻两天线对之间的接地板上蚀刻矩形缺陷地去耦结构,单元间包络相关系数(Envelope Correlation Coefficient,ECC)均小于0.1。对该天线阵列进行加工实测,仿真和测量结果基本一致。A compact broadband high-isolation Multiple-Input Multiple-Output(MIMO)antenna pair is proposed for 5G smartphones.By symmetrically placed the antenna pairs on the inner surface of both side frames,an 8-element MIMO array with low correlation is designed.A compact antenna pair is suggested based on a broadband coupling fed inverted-F antenna(IFA)arranged in null-space mirror symmetry.The-6 dB impedance bandwidth of antenna pair is 3.3~6.5 GHz(65.3%),which covers the 5G bands of n77/n78/n79 and LTE band 46.The size of antenna pair is only 26.8 mm×6 mm(0.29λ0×0.07λ0,λ0 is the free space wavelength of 3.3 GHz).By using the differential/common mode cancellation theory and loading distributed capacitors,the isolation between the two ports of the antenna pair is greatly improved.The isolation in the whole band is higher than 11 dB.Within the n79/LTE band 46(4.4~5.925 GHz),the isolation is higher than 15 dB with the peak isolation of 40 dB at the center frequency point of 4.9 GHz.The total efficiency is 59%~88.8%within the whole band.To improve the isolation of the 8-element MIMO array,a rectangular defective ground structure is etched between two adjacent antenna pairs.The Envelope Correlation Coefficient(ECC)are less than 0.1.A prototype of the proposed MIMO array is fabricated and measured,and the measured and simulated results agree well.

关 键 词：5G 多输入多输出天线 宽带 高隔离度 去耦 

分 类 号：TN822[电子电信—信息与通信工程]