用于金属表面的UHF RFID标签天线优化设计

UHF RFID 标签天线置于金属表面会引起阻抗变化以及阻抗失配,因此为了减小金属表面的影响,提出一种用于金属表面的UHF RFID 标签天线阻抗匹配优化设计方法。首先在折叠偶极子天线臂上附加短路段来调整标签天线的输入阻抗,通过粗略调节短路段的位置使天线和RFID 标签芯片在金属表面达到阻抗的基本匹配,然后利用遗传算法优化得到天线最优的长度、宽度和短路段位置,使天线和RFID 标签芯片在金属表面达到准确的阻抗匹配。所设计天线阻抗及方向图的仿真和测试结果表明该优化设计方法能够使RFID 标签天线在金属表面正常工作。

Optimization Design of UHF RFID Tag Antenna for Metallic Face

When a RFID tag is attached to the metal surface, input impedance of UHF RFID tag antenna will be changed, and even it will lead to impedance mismatching with tag's chip, so a optimization design method of the UHF RFID tag antenna impedance matching for the metal surface is proposed. Firstly, adjusting the position of short-stubs of the dipole antenna roughly, basic configuration of the input impedance of the UHF RFID tag antenna will be gotten, then genetic algorithm is used to optimize length, width and position of short-stubs of the tag antenna, so accurate impedance matching between the dipole antenna and chip of RFID tag can be reached. The simulated and measured results of the designed antenna input impedance and antenna patterns indicate that the optimization design method can make the RFID tag antenna work on the metal surface regularly.