文档介绍：摘要摘要射频识别(Radio Frequency Identification,RFID)技术是上世纪90年代开始兴起并渐渐走向成熟的一种自动识别技术,它利用射频信号及其空间耦合和传输特性进行非接触双向通信、实现对静止或移动目标的阅读和信息采集,具有快速、实时、准确等优点, 已经被世界公认为本世纪最有发展前途的信息技术之一,在生产、零售、物流、交通等各个行业有着广阔的应用前景。因此对射频识别技术以及相关设备的研究和设计有着十分重要的意义。在很多诸如停车场,物流仓储等场合的应用中对RFID的阅读距离有着很高的要求, 一般需要能够实现对无源标签达到10米的阅读距离,这就要求阅读器天线的增益达到 II~12dBi以上,另外考虑到标签天线的极化方式一般为线极化,为了尽量避免漏读的情况发生阅读器天线最好为圆极化方式工作,因此设计一款适用于固定式场合的圆极化高增益阅读器天线一项十分紧迫的任务。本文首先对射频识别技术进行了简要的介绍,包括其系统组成、工作原理等方面; 接着阐述了天线的基本理论以及RFID系统中阅读器天线特点应用指标等;论文的第三部分是作者设计的两款适用于固定式场合的UHF频段高增益的阅读器天线。论文首先分析了高增益读写器天线必须具备的一些基本特性,包括提高增益、高带宽、圆极化、阻抗匹配等;并以此为出发点,研究了微带天线实现高增益、圆极化和展宽带宽的常用方法,并利用三层层叠贴片的结构设计了高增益RFID阅读器天线;接下来又对天线阵理论进行了深入的研究,在以上理论研究的基础上,设计了适用于固定式场合的高增益 RFID阅读器天线阵。关键词:射频识别,阅读器天线,高增益,层叠贴片,天线阵列 Abstract Abstract Radio Frequency Identification(RFID)is a-kind ofautomatic identification technology which has developed very fast since 90’ collects information from the stationary or moving objects by radio fi'equency signals and itsspace coupling and transmission characteristic谢tll advantages of rapid,real-time, has been recognized worldwide as one ofthemostpromising informationtechnology thiscentury,and ithas abroad applicationprospects intheproduction,retail,logistics,transportation and other research and design ofRFID technology and relatedequipment has great significance. Inmany places such舔parking lot,warehouse require thereaders can read much morelonger,maybe 0m topaSsive tags 011average,SO the readerantennas should has a gain morethan thetagantennas usually are linepolarized,SO thereader antenna should becircularlypolarized toavoid itis avery urgent taskto design ahigh—gainandcircularlypolarized readerantenna aSion. The paper firstintroduces therelativetheory andtechnology ofRFID system,inculding ponents,work principle thepaper describes thebasictheory ofthe antenna and thespecial requirements in theapplication thirdpart introducestwo readerantennasdesigned by