一种提高移动终端天线隔离度的方法  

A Method to Improve the Isolation of Mobile Terminal Antenna

作　　者：刘巍 林辉 廖淑敏 郭恒 宋以祥 

机构地区：[1]联想(上海)信息技术有限公司,上海

出　　处：《天线学报》2022年第4期61-68,共8页Journal of Antennas

摘　　要：本文研究移动终端天线的隔离度提高方法。首先通过理论的推导得出了对称设计的天线当共模(CM)与差模(DM)阻抗相等的时候隔离度最优的结论。基于此分析思路提出并设计了紧耦合情况下通过在两个相邻的倒F天线地脚之间同时串联电感和电容来提升隔离度的方法。首先,通过xfdtd仿真软件对比了串联电感和电容前后天线间隔离度的变化。其次,制作了实验治具并对隔离度和回损进行了测试。实验结果表明,此方法在设计频段内隔离度提升约4.5~8.5 dB,仿真和实验结果均表明该方法有效。In this paper, the isolation improvement method of mobile terminal antenna is studied. For the symmetrically designed antennas, the isolation is optimal when the impedances of the common mode (CM) and the differential mode (DM) are equal. Based on this analysis method, a method is proposed to improve the isolation by connecting simultaneously inductance and capacitance in series between two adjacent inverted-F antenna ground points in the case of tight coupling. First, the isolation without and with series inductance and capacitance is compared by the xfdtd simulation software. Secondly, the proposed antenna was manufactured then the isolation and return loss were measured. The experimental results show that this method could improve the isolation by about 4.5~8.5 db in the operational frequency band, and both the simulated and measured results show that the method is effective.

关 键 词：隔离度 移动终端 倒F天线 串联电感 差模 共模 对称设计 回损 

分 类 号：TN820[电子电信—信息与通信工程]