一种新型宽带圆极化UHF RFID读写器天线  

Novel circular polarization planar broadband antenna for UHF RFID applications

作　　者：王斌[1] 何佳佳[1] 孔祥吉[1] 

机构地区：[1]重庆邮电大学光电工程学院,重庆400065

出　　处：《重庆邮电大学学报（自然科学版）》2015年第5期620-625,共6页Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)

基　　金：重庆市科委自然科学基金(cstcjj A40022);重庆市教委科学技术研究项目(KJ120505);重庆邮电大学自然科学基金(A2010-18)~~

摘　　要：针对超高频射频识别(ultra high frequency radio frequency identification,UHF RFID)技术的发展需求,设计了一款覆盖UHF RFID全频段(840—960 MHz)的圆极化读写器天线。天线采用简单的平面缝隙贴片结构,利用π型线耦合馈电,获得了良好的宽带圆极化性能。重点分析了天线的宽带圆极化辐射机理和双向圆极化波的形成过程。天线的仿真和测试结果表明,S11≤-13 d B的阻抗带宽为200 MHz,3 d B轴比(axial-ratio,AR)带宽达到175MHz,频段内增益均大于3.4 d Bi,且顶点的右旋圆极化(right-handed circular polarization,RHCP)电平和左旋圆极化(left-handed circular polarization,LHCP)电平差值均大于17 d B,具有较好的宽带性和抗干扰能力。仿真结果和实验测试结果的一致性良好,满足了UHF RFID读写器天线宽频带、高增益的应用要求。In view of the trend for UHF RFID（ ultra high frequency radio frequency identification） technology,a novel circular polarization（ CP） design of planar broadband（ 840—960 MHz） reader antenna for UHF RFID applications is proposed in this paper. The wideband CP radiation is easily achieved with a novel planar slot patch fed by the π type strip line. It focuses on the broadband CP radiation mechanism and the formation of double CP radiations of the antenna. The simulation and measurement results show that the impedance bandwidth of S11≤-13 d B is about 200 MHz and the 3 d B axial-ratio（ AR） bandwidth is about 175 MHz,while the gain in the whole band is greater than 3. 4 d Bi,the differences between right-handed circular polarization（ RHCP） levels and left-handed circular polarization（ RHCP） levels exceed 17 d B. The proposed antenna exhibit excellent operating bandwidth and a strong anti-interference capability. Close agreement is obtained between simulation and measurement results,it is supposed to meet the requirements of wideband and high gain for UHF RFID applications.

关 键 词：读写器天线 宽带 圆极化 超高频射频识别技术(UHF RFID) 

分 类 号：TN129[电子电信—物理电子学]