通信工程文献翻译——摘要：设计一个读取频率为2.4HGz八木RFID背瓣标签天线。由于EIRP（有效全向辐射功率）是有限的，扩展阅读范围内的标签的增益和前back ratio标签应该是高八木天线。根据ISO18000-4国际标准，在阅读器和读取器的EIRP天线约30mW的。它比超高频RFID的EIRP值较低带。用优化的5个元素八木天线的标签遗传算法（GA）具有低后瓣。5种元素尺寸和八木天线的间距进行了优化与GA。主瓣的增益8.2分贝和后瓣被减少到0dB。2.4GHz的八木型标签的性能天线比一般类型的标签天线和传统的八木天线的标签好。

关键词：2.45GHz的RFID标签，八木RFID标签，RFID标签，遗传算法。

一、引言

RFID（无线射频识别）系统是在广泛的领域，如售票用，银行，智能标签，电子护照，动物ID，跟踪容器等一般的RFID系统由应答器（标签），读取器天线和一台计算机连接到读取器。读者有一个或多个天线，并且标签包括RFID IC芯片和连接到所述RFID天线芯片的标签天线的馈电点。该的RFID系统的操作原理是以下几点：读者通过阅读器天线将信号传送到标签天线。被动标签接收所有从读写器的载波信号所需要的能量天线的基础上，后向散射方法。

根据ISO-18000（国际标准组织），的操作的频率范围2.45GHz的RFID频带为2400-2483.5MHZ，并且带宽大约为83MHz。这是狭隘的带宽比超高频RFID频段860?960MHz的。一个阅读器和阅读器天线的EIRP是为限制为30mW。延长标签天线的读取范围内，唯一的办法就是增加了标签天线的增益。的2.4GHz的频率比UHFRFID较高所以标签天线的尺寸更小。因此，2.45GHz的RFID系统的应用可以是应用到更小的物体和系统。

一般2.45GHz的标签的读取范围地使用有关5?10cm的基础上，日立mu芯片标记。至

扩展标记时，八木宇田的读取范围天线被应用。八木天线由一个驱动单元，一个或多个董事及反射器。光束模式是端射式，它具有良好的FBR（前端到后端的比例）和高指向性。

在RFID IC芯片的阻抗有实数阻性损耗和由于负虚值RFID芯片的寄生电容。要匹配芯......

Abstract — A long reading range 2.4HGz Yagi-Uda RFID tag antenna with low back-lobe is designed. Since the EIRP (Effective Isotropic Radiation Power) of the reader is limited, to extend a reading range of the tag, the gain and front-backratio of the tag should be high as Yagi-Uda antenna. According to ISO 18000-4, the EIRP of the reader and reader antennas is about 30mW. It is lower than EIRP of UHF RFID band. The optimized 5 elements Yagi-Uda tag antenna with a genetic algorithm (GA) has low back-lobe. The 5 elements sizes and spacing of Yagi-Uda antenna are optimized with a 

GA. The gain of main-lobe is 8.2dB and back lobe is reduced to 0dB. The performance of the 2.4GHz Yagi-Uda type tag antenna is better than that of general type tag and conventional Yagi-Uda tag antennas. 

Index Terms — 2.45GHz RFID Tag, Yagi-Uda RFID Tag, RFID Tag, Genetic Algorithm.

I. INTRODUCTION

RFID (Radio Frequency Identification) system is used in the wide fields such as ticketing, banking, smart labels, electronic passports, animal ID, tracking containers and etc. A general RFID system 

consists of a transponder (tag), a reader antenna and a computer connected to the reader. The reader has one or multiple antennas, and the tag consists of RFID IC chip and an antenna connected to the RFID chip at the feeding point of the tag antenna. The principle of RFID operation system is following: the reader transmits the signal through reader antennas to the tag antennas. The passive tag receives all the required energy from the carrier signal of the reader antenna based on the backscattering methods [1-3]. According to ISO-18000 (International Standard Organization), the operated frequency range of the 2.45GHz RFID band is 2400-2483.5MHz, and the bandwidth is about 83MHz [4]. It is narrow bandwidth than the UHF RFID band 860~960MHz. 

The EIRP of a reader and reader antenna is limited as 30mW. To extend the reading range of a tag antenna,......