木托盘RFID标签安装方式有限元分析及试验研究

目的 采用仿真和试验手段并用的方法,研究RFID标签在木质平托盘上的适用安装方式及其对使用性能的影响。方法 进行Ansys有限元仿真,分析木质平托盘承载和冲击试验中采用螺钉紧固及黏结剂粘贴方式安装的RFID标签所受应力。作为对比,在实验室进行实物试验,测量RFID标签表面应力,并测试标签读写性能。结果 在托盘承载和冲击试验中,从RFID标签各构件及标签连接件的受力分析看,2种安装方式下的RFID标签均未出现脱落和物理性损坏。冲击试验后的RFID标签能够通过读写功能测试。有限元仿真与实物试验的应力分析结果相互吻合,验证了结果的正确性。结论 RFID标签采用螺钉紧固和黏结剂粘贴的安装方式都能满足使用要求,且螺钉连接的耐用性更好。研究结果为RFID标签在木质平托盘的安装方式选择提供了理论依据。     

判断二进制树中标签识别完毕的方法

分析了射频识别(RFID)系统阅读器与标签通信的二进制树算法,指出在标签识别过程中,阅读器并不知道是否识别完标签,阅读器会以连续多次没有接收标签响应为依据结束对标签的查询,这样往往会造成标签漏读或浪费时间在已识别完的标签上。基于此分析,提出了判断二进制树中标签识别完毕的方法。该方法通过在阅读器中设置计数器,就可以很好地跟踪标签的识别情况,准确地判断出标签是否识别完毕。分析结果表明,该方法可以准确地判断标签是否识别完毕,增加系统识别效率和可靠性。     

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.     

应用无线射频识别技术的配送中心系统设计

将高频和超高频RFID设备规划于同一配送中心管理系统之中,通过解决不同设备间相互"串读"的问题,使其分别读取电子标签数据信息并承担相应配送环节的数据采集任务.设备控制以及各设备与中心系统之间的数据传输通过RS232串口、有线及无线局域网的通讯方式来完成.为实现过滤不同类型的标签,提出在标签的数据块中设置标志符来加以区分的新方法.系统应用层囊括了入库管理、库存管理、出库管理、资源管理以及报表管理等配送中心实际功能模块,最终实现完全基于RFID技术的完整的配送中心实验室模拟系统.     

Mobile RFID Tag Detection Influence Factors and Prediction of Tag Detectability

Radio-frequency identification (RFID) readers are powered RF devices that communicate with tags (whether mobile or fixed) and read necessary information to be processed. A mobile RFID tag is detected by an RFID antenna. In a mobile RFID where the RFID tag is attached to a mobile object such as a vehicle, a human, or an animal, information is more difficult to detect than in the case where the tag is attached to a stationary object. Currently, deployment engineers and researchers use trial-and-error approaches to decide on the best conditions of the tag detection influence factors which affect tag detectability (detection rate). As expected, these approaches are time consuming. Even though mobile RFID systems have become widely used in industry and tag detection problems are crucial at deployment, very few researches on them have been conducted so far. Thus, a quick and simple method for finding tag detectability is needed to improve the traditional time consuming trial-and-error method. In this paper, we propose a unique approach ldquothe intelligent prediction method of tag detection rate using support vector machine (SVM).rdquo The intelligent method predicts the mobile RFID tag detectability instead of the trial-and-error experimental procedures. The simulation results of the proposed method are very comparable to the trial-and-error experimental approach. The proposed intelligent method gives a very high accuracy of mobile RFID tag detectability prediction and proves to be superior to the current method in time as well cost savings. The predicted tag detectability results can be used for analyzing mobile RFID tag detection influence factors and their conditions.     

An RFID-based power meter and outage recording system

Radio frequency identification (RFID) is looked upon as one of the top ten important technologies of the twentieth century. In coming years, public area applications are the key issue in developing RFID. Power systems are innately bulky, large, and definitely, an extremely important application area for RFID. In power areas, RFID has great potential to be applied extensively to customers. Therefore, an RFID-based power meter and outage recording system is proposed in this article. The proposed system can be used to fully collect and record power consumption data and power reliability information on customers. A small-scale power meter and outage recorder is designed first and then an RFID system is designed and embedded into the power meter and employed to record the power data in tags. A handheld meter management system is also designed in this article to collect the data stored in the tags and synchronize the collected data with rear-end processing if necessary. Due to the uniqueness of RFID tags, the power consumption data and outage information on customers can be recorded and then identified in a rear-end processing system. Experimental results show the validity of the proposed system.     

A Frame Breaking Based Hybrid Algorithm for UHF RFID Anti-Collision

Multi-tag collision imposes a vital detrimental effect on reading performance of an RFID system. In order to ameliorate such collision problem and to improve the reading performance, this paper proposes an efficient tag identification algorithm termed as the Enhanced Adaptive Tree Slotted Aloha (EATSA). The key novelty of EATSA is to identify the tags using grouping strategy. Specifically, the whole tag set is divided into groups by a frame of size F. In cases multiple tags fall into a group, the tags of the group are recognized by the improved binary splitting (IBS) method whereas the rest tags are waiting in the pipeline. In addition, an early observation mechanism is introduced to update the frame size to an optimum value fitting the number of tags. Theoretical analysis and simulation results show that the system throughput of our proposed algorithm can reach as much as 0.46, outperforming the prior Aloha-based protocols.     

无源RFID标签用材料研究进展

射频识别(RFID)是一种非接触式的自动识别技术,它是物联网的核心技术。该技术通过射频信号自动识别目标对象并获取相关信息数据,该识别工作不需要人工干预,RFID标签可在各种恶劣环境中工作。RFID的应用非常广泛,尤其是在服装、资产管理等方面的应用最为成熟。RFID标签是RFID技术中必不可少的重要组成部分。随着新材料、新工艺的出现与发展,RFID标签的新产品不断地涌现出来,就近年出现的一些与新材料密切相关的RFID标签新产品与新制造工艺、方法进行了总结。新材料的发展与新工艺的出现为物联网核心技术RFID标签产业提供了新的技术方向和新的经济增长点。     

电子标签在集装箱循环使用中的应用

介绍了电子标签的工作原理、优点及如何采用丝网印刷工艺获得电子标签;分析了集装箱物流管理中3种船公司的集装箱管理部门;从实际回收情况中得出,电子标签在集装箱循环使用中的作用.     

基于改进ALOHA算法的RFID标签防碰撞研究

目的 为提高射频识别技术(Radio Frequency Identification,RFID)标签识别成功率,以及包装生产线自动分拣效率、智能化水平.方法 以包装生产线检测系统为研究对象,结合RFID技术设计一种自动包装、检测、配送系统.介绍RFID检测系统,主要包括标签、阅读器、天线和控制系统.针对RFID识别过程中标签碰撞问题,提出一种改进ALOHA算法,采用动态预测权值估计标签数目使标签数目与数据帧长度大致相等.通过实验验证ALOHA算法的有效性.结果 实验结果表明,碰撞比率平均值只有1.1％,整个系统的检测成功率可以达到99.6％;所述改进ALOHA算法可以有效避免标签碰撞.结论 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,具有较高的市场应用价值.     

Evaluation of an innovative system for improving readability of passive UHF RFID tags attached to reusable plastic containers

Radio frequency identification (RFID) is a contactless identification technology that has proven to work well in conjunction with reusable plastic containers (RPCs). The impact of this technology on returnable containers has been explored by several past studies. This study evaluates an innovative system for improving readability of passive UHF RFID tags in conjunction with RPCs. The system involves an energy transfer device (ETD), which when attached to the RPCs, passively transfers radio frequency signals to interior regions of a unitized load thereby improving the readability of all RFID tags attached to the RPCs. This study included an evaluation of the improvement in readability of tagged RPCs in a unitized load with forklift truck speed, product type and pallet pattern as the variables and with readability as the main control variable. It was observed that ETDs vastly improve the readability rates by nearly 97%. Results are also included in this paper describing the effects of the product type, pallet patterns and forklift truck speeds on the readability of tagged RPCs in a unitized load. Copyright © 2011 John Wiley & Sons, Ltd.     

基于二进制树的RFID系统自适应多分支防碰撞算法

为提高射频识别(RFID)系统的识别效率,研究了系统的标签防碰撞问题。考虑到对标签进行多分支处理能够有效地提高RFID系统标签识别效率,而传统的多分支防碰撞算法都是在标签估计的基础上对标签进行最优分组,标签估计产生的时延和误差都会影响整体的识别效率,提出了一种基于二进制树的自适应多分支(AMB)防碰撞算法。该算法根据二进制树结构特点,利用识别的标签数目对树结构中右节点标签进行估计并进行分组识别,经过多次调整的自适应多分支防碰撞算法,可以规避一次标签估计所引入的估计误差,从而提高系统的识别效率。仿真结果表明自适应多分支算法可以大大提高标签识别效率,在标签数量较大时系统效率可达43%左右。同时该算法实现简单,只需在阅读器中增加若干计数器,不需要改变任何空中接口,很容易与现有协议兼容。     

Inline SAW RFID tag using time position and phase encoding

Surface acoustic wave (SAW) radio-frequency identification (RFID) tags are encoded according to partial reflections of an interrogation signal by short metal reflectors. The standard encryption method involves time position encoding that uses time delays of response signals. However, the data capacity of a SAW RFID tag can be significantly enhanced by extracting additional phase information from the tag responses. In this work, we have designed, using FEM-BEM simulations, and fabricated, on 128 degrees -LiNbO3, inline 2.44-GHz SAW RFID tag samples that combine time position and phase encoding. Each reflective echo has 4 possible time positions and a phase of 0 degrees , -90 degrees , -180 degrees , or -270 degrees. This corresponds to 16 different states, i.e., 4 bits of data, per code reflector. In addition to the enhanced data capacity, our samples also exhibit a low loss level of -38 dB for code reflections.     

Improved Method for Object Recognition in Complex Scenes by Fusioning 3-D Information and RFID Technology

This work analyzes a new method for object recognition in complex scenes combining vision-based techniques applied to the 3-D data obtained using range sensors and object identification coming from radio frequency tags (radio frequency identification (RFID) technology). Three-dimensional vision-based algorithms for object recognition have many restrictions in practical applications, i.e., uncertainty, incapability for real-time tasks, etc., but they work well for pose determination once the object is recognized. On the other hand, RFID technology allows us to detect the presence of specific objects in a scene, but it cannot provide their localization, at least not with the accuracy required in applications such as ours. In this paper, we present a new and powerful recognition method obtained by fusing both techniques. The phases of the method are described, and abundant experimentation results are included. An in-depth performance analysis has been carried out to demonstrate the recognition improvements achieved by the algorithm when RFID assistance is considered. It helps to confirm the robustness of this fusion approach and prove its effectiveness. A final discussion is included, concerning what should be the most adequate size of the object database for optimal algorithm exploitation.     

Z-path SAW RFID tag

Surface acoustic wave (SAW) radio-frequency identification (RFID) tags are soon expected to be produced in very high volumes. The size and cost of a SAW RFID tag will be key parameters for many applications. Therefore, it is of primary importance to reduce the chip size. In this work, we describe the design principles of a 2.4-GHz SAW RFID tag that is significantly smaller than earlier reported tags. We also present simulated and experimental results. The coded signal should arrive at the reader with a certain delay (typically about 1 micros), i.e., after the reception of environmental echoes. If the tag uses a bidirectional interdigital transducer (IDT), space for the initial delay is needed on both sides of the IDT. In this work, we replace the bidirectional IDT by a unidirectional one. This halves the space required by the initial delay because all the code reflectors must now be placed on the same side of the IDT. We reduce tag size even further by using a Z-path geometry in which the same space in x-direction is used for both the initial delay and the code reflectors. Chip length is thus determined only by the space required by the code reflectors.     

A Dynamic Multi-ary Query Tree Protocol for Passive RFID Anti-collision

In this paper, a dynamic multi-ary query tree (DMQT) anti-collision protocol for Radio Frequency Identification (RFID) systems is proposed for large scale passive RFID tag identification. The proposed DMQT protocol is based on an iterative process between the reader and tags which identifies the position of collision bits through map commands and dynamically encodes them to optimize slots allocation through query commands. In this way, the DMQT completely eliminates empty slots and greatly reduces collision slots, which in turn reduces the identification time and energy costs. In addition and differently to other known protocols, the DMQT does not need to estimate the number of tags, reducing the protocol implementation complexity and eliminating the uncertainty caused by the estimation algorithm. A numerical analysis shows that DMQT has better performance than other algorithms for a number of tags larger than 300. Meanwhile, when the number of tags is 2000 and the tag identity (ID) length is 128 bits, the total identification time is 2.58 s and the average energy cost for a tag identification is 1.2 mJ, which are 16.9% and 10.4% less than those of state-of-the-art algorithms, respectively. In addition, a DMQT extension based on ACK command has also been presented to deal with capture effect and avoid missing identification.

     

RFID research and testing for packages of apparel,consumer goods and fresh produce in the retail distribution environment

Radio frequency identification (RFID) is a term used for any device that can be sensed at a distance by radio frequencies with few problems of obstruction. The origins of the term lie in the invention of tags that reflect or retransmit a radio‐frequency signal. According to a recent article by Forrester Research, the minimal ‘Slap and Ship’ approach to RFID compliance will cost an individual company between $2 million and $20 million. Because retailers like Wal‐Mart plan to share with their suppliers all the RFID‐generated data points (from when a case/pallet enters their distribution centre until it leaves their stockroom), suppliers will eventually be able to use this data as a powerful forecasting tool. RFID is an enabling technology that can potentially facilitate a real‐time, end‐to‐end supply chain visibility system. Suppliers who integrate full‐scale RFID systems will realize efficiencies in time, material movement, inventory planning, shipping and warehousing both internally and externally. This paper provides a brief overview of the RFID technology, mandates by retailers and federal agencies, advances towards global standardization and typical consumer level RFID applications, and discusses RFID initiatives taken by some of the global leaders in apparel, consumer goods and fresh produce industries. Copyright © 2007 John Wiley & Sons, Ltd.     

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.     

An evaluation of the ability of RFID tags to withstand distribution of fresh produce in the RPC pooling system

This study focused on the ability of radio frequency identification (RFID) tags applied on reusable plastic containers (RPCs) to withstand repeated abuse due to physical distribution and storage environment related hazards. It also studied the effect of the chemical cleaning environments that RPCs are commonly exposed to in the pooling/rental systems commonly used to distribute fresh produce. RPCs are being successfully deployed in the US, Europe and Asia to ship fresh produce from growers to retailers. The increasing demand for traceability and tracking of fresh produce from ‘farm to fork’ requires these containers to be monitored and identified in the food supply chain, and RFID technology provides one of the solutions. This study compared eight commercially available RFID tags mounted on RPCs for use in fresh produce distribution and subjected them to repeated physical and climatic cycles representing the distribution and cleaning environments, and their effective ‘read’ capabilities were tested. Copyright © 2010 John Wiley & Sons, Ltd.     

Feasibility of ultra-wideband SAW RFID tags meeting FCC rules

We discuss the feasibility of surface acoustic wave (SAW) radio-frequency identification (RFID) tags that rely on ultra-wideband (UWB) technology. We propose a design of a UWB SAW tag, carry out numerical experiments on the device performance, and study signal processing in the system. We also present experimental results for the proposed device and estimate the potentially achievable reading distance. UWB SAW tags will have an extremely small chip size (<0.5 times 1 mm²) and a low cost. They also can provide a large number of different codes. The estimated read range for UWB SAW tags is about 2 m with a reader radiating as low as <0.1 mW power levels with an extremely low duty factor.