无线电子标签读写器天线的研究

天线是射频识别技术(radio frequency identification,RFID)中读写器的重要组成部分.实验测定了天线尺寸、品质因数、天线电感值以及金属环境对天线性能的影响,发现天线的读写距离大约为天线内部直径的2倍;品质因数最好为13～20;最佳电感值为700μH;金属环境会对天线性能的影响包括读写器天线与金属距离、金属材料、金属板开孔大小以及应答器安装孔的大小,最后给出了改善天线性能的4种方法.     

Readability and Modulated Signal Strength of Two Different Ultra‐high Frequency Radio Frequency Identification Tags on Different Packaging

Radio frequency identification (RFID) does not require the line‐of‐sight scanning, which is a benefit in comparison with barcodes; moreover, it is believed that it improves the inventory management. Nowadays, this is still a costly solution; however, in the near future, it is expected to become widespread especially in packaging. This paper analyses some effects that have to be considered before the application of the system on packaging. The readability of two ultra‐high frequency RFID tags with different antenna sizes and shapes but the same reading range as stated by the supplier was evaluated. The influence of water and metal was analysed by labelling each tag onto an empty corrugated box, a box filled with water and a box covered with aluminium foil on the inside. The read rate in a line‐of‐sight and the readability in a horizontal plane were measured, applying a horizontal linearly polarized wave. The strength of the signal in a direct line‐of‐sight between the reader antenna, and RFID tag was measured with circularly polarized waves. The obtained results confirmed the effects of the tagged antenna and of the labelled boxes content. To show the effect clearly, the influence of metal and water on the two‐dimensional horizontal tag readability was measured and presented with two‐dimensional sketches of tag reading/non‐reading zones. Different results were obtained for both tags, with the content of labelled boxes having a great influence. Copyright © 2011 John Wiley & Sons, Ltd.     

Radio frequency identification (RFID) performance: the effect of tag orientation and package contents

The objective of this research was to determine the relationship between different product types and tag orientations on the readability of RFID tags on shipping containers in a palletload that is driven through a portal type reader. This research finds that the content of packages can dramatically reduce the read rate. Only 25% of the tags on shipping containers containing water‐filled bottles could be read. Rice‐filled jars had a higher read rate (80.6%). Even empty boxes did not have a 100% read rate. For the variables without appreciable package contents, only 74–79% of loads had all of their tags read. The orientation of the tag does make a difference, especially when coupled with a filled package between it and the reader antennae. Tags facing outwards, towards the reader antennae, had the highest likelihood of a successful read. When tags for the boxes of water‐filled bottles were all facing downwards, no tags were read. Supply chain managers need to understand these limitations of the technology and find ways to overcome them before RFID can be successfully implemented in supply chains. Copyright © 2005 John Wiley & Sons, Ltd.     

低功耗无源超高频射频识别应答器芯片的射频电路设计与实现

提出了一种符合ISO/IEC 18000-6B标准的高性能低功耗无源超高频(UHF)射频识别(RFID)应答器芯片的射频电路.该射频电路除天线外无外接元器件,通过肖特基二极管整流器从射频电磁场接收能量.其构成包括本地振荡器、时钟产生电路、复位电路、匹配网络和反向散射电路、整流器、稳压器以及AM解调器等几个主要模块.该射频电路芯片采用支持肖特基二极管和EEPROM的chartered 0.35μm 2P4M CMOS工艺进行流片,测试结果表明其读取距离大于3m,在915MHz ISM频带下工作时其电流小于8μA,该芯片核心面积为300μm×720μm.     

基于RFID的药品生产管理及包装信息化

基于射频识别(RFID)的药品生产管理信息化需做到在药品整个生产周期及管理过程的可追溯性,可实现从药品原材料、生产过程、流通过程、销售过程,到消费者安全使用的全程信息化追溯。同时,药品的整个监管过程中也需信息化,并构建完善的药品监管溯源体系。基于RFID的钱夹式药品包装不仅给服用者以更灵活、理性的消费体验,还可通过终端连接制作厂商或药房医院,给消费者提供辨伪咨询等服务。药品生产管理及包装信息化模式虽然存在成本较高、应用平台整合难度大等问题,但其价值体现在能使高度复杂的数据共享成为现实,可帮助我国改善包装机械和制药行业打破"小而散"的行业态势,同时还能减少企业人工与管理成本,完善流通与销售监管,因此,具有较好的市场发展前景。     

Graphene-Based RFID Tag Antenna for Vehicular Smart Border Passings

Globalization has opened practically every country in the globe to tourism and commerce today. In every region, the volume of vehicles traveling through border crossings has increased significantly. Smartcards and radio frequency identification (RFID) have been proposed as a new method of identifying and authenticating passengers, products, and vehicles. However, the usage of smartcards and RFID tag cards for vehicular border crossings continues to suffer security and flexibility challenges. Providing a vehicle's driver a smartcard or RFID tag card may result in theft, loss, counterfeit, imitation, or vehicle transmutation. RFID sticker tags would replace RFID tags as vehicle border passes to solve the mentioned problem. The RFID sticker tag adheres to the windscreen, side screen, dash, hood, or door of the vehicle, or any other acceptable location. Any damage or stripping from the installed location may cause data corruption and cannot be reused. Overall, these sticker tags will make the border crossings more secure and efficient. This article focuses on designing a rectangular-shaped RFID sticker tag antenna made of graphene sheets as a possible solution for smart border crossings. The proposed antenna is mathematically designed and analyzed with CST software to determine the optimum parameters. The design parameters are then used to create an antenna on a prepared graphene sheet. The performance results are carried out with CST software and a network analyzer. The designed RFID antenna stick on a car windscreen offers approximately 900 MHz bandwidth over the frequency range from 1.8 GHz to 2.7 GHz with an average gain of 1.23 dBi at the frequency to be used of 2.4 GHz microwave RFID band. The radiation is an omnidirectional pattern. The proposed graphene-sheet rectangular-shape monopole antenna is compact, low-cost, and bendable to fit into the windscreen of a car while retaining excellent wave propagation capabilities. These findings illustrate the suggested antenna's potential as an RFID tag antenna in a vehicular smart border pass system.     

The effects of item composition,tag inlay design,reader antenna polarization,power and transponder orientation on the dynamic coupling efficiency of backscatter ultra‐high frequency radio frequency identification

The effects of packaged content, packaging material, transponder inlay design, reader antenna polarization, interrogation power and transponder orientation on the detection rate of ultra‐high frequency radio frequency identification (UHF RFID) passive transponders were studied. The influence of individual factors and their interactions were determined using general linear model analysis of variance. Influences originated in order of importance, from sample type, antenna polarization, power and inlay design. Important interactions in decreasing order of significance exist between: power and antenna polarization; sample type and antenna polarization; sample type and inlay design; inlay design and antenna polarization; sample type, power and antenna polarization; sample type and power; inlay design and power; sample type, inlay design and power. It was also observed that random orientation of tags did not cause a statistically significant variation in tag detection rate. It can be concluded that the use of UHF RFID for item level of food requires multi‐parameter assessment before hand. Copyright © 2009 John Wiley & Sons, Ltd.     

Tag identification enhancement by using a distributed antenna structure for radio frequency identification systems

This study presents a distributed antenna structure operating at a frequency of 915 MHz to increase the tag identification sensitivity for passive radio frequency identification (RFID) systems. The distributed antennas are connected to a reader with a four-port power splitter/combiner which consists of Wilkinson power splitters (WPSs), band pass filters (BPFs) and power amplifiers (PAs). Due to the polarisation of the electromagnetic field, the antennas are positioned on opposite sides in both vertical and horizontal directions of the object. This positioning improves the performance of the system, and increases the sensitivity when identifying unclearly positioned tags. An experimental RFID system is also set up to demonstrate the proposed structure. Simulation and experimental results indicate that using four distributed patch antennae can improve tag identification in passive RFID systems.     

Automatic identification in packaging — radio frequency identification in multiway systems

With regard to the increasing environmental awareness all over the world, many companies replace their one‐way packaging systems by reusable systems in order to save energy and resources and to reduce waste. But complex multiway networks entail several problems concerning the availability of returned empties and the control of the flow of materials. In order to guarantee a failure‐free operation of the logistic network at low cost, a complete tracking and tracing of the package based on efficient identification technologies is crucial. Concerning multiway systems, the requirements of a continuous information flow often exceed the capacity of barcode technologies. Radio frequency identification (RFID) technologies can fill this gap by offering the wide range of features necessary for disposition and control. This paper sets out the requirements and benefits connected with the use of RFID technologies using multiway systems that represent new results from current research projects. Copyright © 1999 John Wiley & Sons, Ltd.     

基于RFID的包装生产线检验系统的设计与研究

目的为了提高包装生产线上的产品检验效率,保证检验过程的正确率。方法在充分研究RFID射频技术、防伪算法与防碰撞算法的基础上,借助于RFID读写功能设计一套用于识别包装生产线上产品的检验系统,来对生产线上输送的出厂物品进行检测和管理。结果在设计包装生产线整体硬件结构的基础上,结合RFID硬件处理模块和PC机人机交互界面,对包装生产线上300个贴有电子标签的产品进行了检验实验,该系统能够自动完成检验,并且用时较少,检验过程中正确率较高。结论该设计的检验系统能够提高包装生产线的检验效率,具有较高的市场应用价值。     

嵌入式RFID系统识别率关键因子的分析

为提高RFID系统识别率,优化设计RFID系统,需要确定影响RFID系统识别率的关键因子.基于关键过程输入变量、关键过程输出变量的模型,提出了一种分析影响RFID系统识别率关键因子的试验设计方法,并确定了关键因子为标签与读写器平面夹角、读写器天线数量、标签与读写器距离.通过测试,分别在标签嵌入汽车轮胎未硫化和硫化两种情况下,进一步确定影响嵌入式RFID系统识别率的各关键因子.最后,应用MINITAB统计软件,采用二项logistic的回归分析方法,分析了各关键因子对识别率的贡献情况.统计分析结果有利于优化设计RFID系统,提高RFID系统识别率.     

Performance characterization of screen printed radio frequency identification antennas with silver nanopaste

The era of wireless communication has come and it is going to flourish in the form of radio frequency identification (RFID) tags. The employment of RFID tags in daily commodities, however, is constrained due to the manufacturing cost. Therefore, industries in the field have sought for alternative manufacturing methods at an ultra low cost and various printing processes have been considered such as inkjet, gravure, flexo, off-set and screen. Although such printing processes are age-old, their applications have been mainly limited to graphic arts and design rules for electronic appliances have not been fully established yet. In this paper, the selection of ink and printing process to fabricate RFID antennas is discussed. The developed silver nanopaste in the range of 20 to 50 nm without the inclusion of microparticles and flakes was sintered at 120 °C for 1 min, which is lower than that of conventional silver paste with microparticles and flakes, and its resistivity was found to be approximately 3 μΩ cm. The radiation performances of various screen printed RFID antennas with silver nanopaste were found comparable to those of copper etched ones.     

Examining the small world phenomenon in the patent citation network: a case study of the radio frequency identification (RFID) network

Despite strategic research has been done in recent years to study how network topology shapes the evolution of competition in various industries, previous researches do not investigate the importance of high betweenness point on the connectivity of patent citation networks. The goal of this report is to examine and characterize the small world phenomenon in the patent citations network by analyzing the data of RFID patents. The results suggest that the patent citation network can indeed be characterized as “small world”. Additionally, the patent citation network resembles the power-law connectivity distribution and exhibits preferential connectivity behavior. In other words, a few key patents have a great many more connections than the majority of patents with few connections. Furthermore, the patents of high betweenness centrality were identified. It is found that 81% of the patent citation activities have relations with the patents of high betweenness centrality. The result of this analysis will provide a specific way for managers to identify key patents, to map their own patent deployment and to derive insight into the best ways to navigate within such networks.     

RFID丝印墨层厚度影响因素的研究

介绍了丝网印刷RFID标签天线的工艺特点;在分析了标签天线电阻的计算方法的基础上,提出了天线电阻主要受天线墨层厚度和导电油墨导电性能两方面的影响。分别分析了丝网、刮墨刀、丝网目数等因素对天线墨层厚度的影响,以及导电油墨的黏度及导电油墨的干燥效果对其导电性能的影响。为实际生产中,调整丝印RFID天线的电阻提供理论参考。     

Thermal characterization of screen printed conductive pastes for RFID antennas

Thermal resistance is an essential aspect of electronic circuits designing. It leads to unexpected changes in electronic components during their work. In this study, new materials for screen printed RFID tag's antennas were characterized in terms of their resistance to thermal exposure. Polymer materials containing silver flakes, silver nanopowder, carbon nanotubes or conductive polymer PEDOT:PSS were elaborated and used for antenna printing on flexible materials. In order to verify their long term susceptibility to damages caused by the changing environmental conditions, the temperature cycling test was used in three different temperature ranges: +65 °C, −12 °C, −40 °C/+85 °C (3 h in each temp., dwell time 1 h). The highest durability to thermal exposure exhibited the paste with carbon nanotubes dispersed in poly(methyl methacrylate) PMMA and the lowest one – the paste with conductive polymer PEDOT:PSS.     

RFID技术及其在智能包装中的应用

目的介绍国内外RFID技术的基本原理以及在智能包装中的应用,为RFID技术的后续发展与应用提供参考。方法详细介绍RFID技术与智能包装的结合,在商品仓储管理、零售管理、医疗管理以及身份识别等场景的应用现状。结果 RFID技术作为一种新型通信技术,有着巨大的市场应用前景,通过与传统条形码的对比,RFID技术通过信息感应就能实现数据统计,不再需要逐个扫描,大大节省了人力和物力,但由于RFID设备造价昂贵,导致RFID电子标签成本偏高,严重限制了其在智能包装领域的发展应用。结论结合了RFID技术的新型智能包装可通过信息感应实现数据的快速准确统计,不需要人工逐个扫描商品包装,节省了劳动力成本,安全高效。     

Investigation of RFID tag readability for pharmaceutical products at item level

Background: The applications of radio frequency identification (RFID) technology carry a tremendous potential for pharmaceutical industry. There is a pressing need to analyze the performance of RFID tags attached to various pharmaceutical dosage forms. Method: The readability of RFID-tagged pharmaceutical products is, for the first time, systematically investigated by experiments. Factors considered include dosage forms, ion concentration in solution, angle of rotation, and distance between the RFID tag and the interrogator. Results: Compared with empty container, the filling of any representative dosage forms causes deteriorated readability for the tag attached to container. Analysis of variance reveals that the effects of dosage forms, angle of rotation, and their interaction are statistically significant. In addition, an increase in distance (equivalent to higher RF attenuation level) and higher ion concentration in solution beyond a certain level have detrimental effect on tag readability. Conclusion: The analysis shows that the RFID tag readability is strongly dependent on the factors that are experimented with. The level of the factors for optimum RFID system performance should be adjusted based on the particular application.     

RFID天线的丝印工艺研究

为分析优化RFID天线的丝网印刷过程并提高其印刷质量,对丝网印刷工艺对天线印刷精度的各种影响因素进行了分析,包括网目数、印版特性、刮刀角度等各项参数。通过优化丝印工艺参数,印刷了RFID天线并测量了作为主要参数之一的阻抗,结果表明其阻抗波动较小,丝印工艺可满足天线印刷的质量要求。     

广东省RFID产业标准体系建设的SWOT分析

文章通过采用SWOT分析法,研究了开展广东省RFID产业标准体系建设的优势、劣势、机遇及威胁,建立了SWOT分析矩阵表,从而为后续RFID产业标准化发展提供指导,为其他省市乃至国家RFID产业标准建设提供示范。     

导电油墨厚度对RFID标签天线辐射效率的影响

为提高RFID电子标签天线的辐射效率,从理论上分析了影响标签天线辐射效率的一系列因素,以偶极子和叠缝隙2种天线为研究对象,研究了导电油墨厚度对RFID标签天线的辐射效率的影响。结果表明:决定天线的辐射效率的是印刷标签天线所用的总油墨量,而不是整个天线结构中不同区域内油墨的分布情况。为实际RFID电子标签生产中导电油墨的控制和改进,提供一些指导。