基于nRf2401的高速路不停车收费系统

以射频识别（RFID）技术为核心的电子不停车收费系统（ETC）能够有效提高高速公路收费的工作效率。提出了一种以AT89S52、nRf2401无线收发芯片为基础的车辆自动收费系统,通过nRf2401无线通信交互通信各种信息,并将信息储存在上位机系统和用户卡中,最终实现自动收费。     

电子不停车收费系统车载单元设计

本文基于电子不停车收费系（ETC）,提出了一种车载单元设计方案,并设计了电子不停车收费系统车载单元的软件和硬件部分。其中,硬件部分以STC单片机为核心,通过扩展的IC卡接口和射频接口等设备完成系统的各项功能;软件部分完成了车载单元与路侧单元的通信,并使车载单元可以通过LCD与用户交互。由此可见,以单片机为核心开发ETC车载单元是完全可行的。     

射频识别标签用导电银胶研究进展

介绍了射频识别(RFID)技术和射频识别电子标签的概念、特点及应用,阐述了射频识别电子标签用导电银胶的性能要求,例举了国外典型产品的技术指标,对比分析了超细片状银粉、银纳米线、碳纳米管及镀银碳纳米管等制备的导电银胶特性,提出了电子标签用导电银胶的研究重点。     

射频识别系统及其产品

通过射频识别(RFID)技术自动识别目标对象并获得相关数据的非接触式RFID系统由电子标签、读写器和天线组成。电子标签的工作频率决定该系统的工作原理和识别距离。RFID产品的特点及适用场合:低频产品(125 k Hz~135 k Hz)具有良好的物体穿透性,适用于门禁、考勤、动物、固定设备等的管理;高频产品(13.56 MHz)适用于防伪、供应链、生产管理等;超高频产品(860 MHz~960 MHz)读写距离较远,适用于电子牌照、仓库管理等;微波产品(2.45 GHz)都为有源产品,读写距离可高达百米,主要应用于定位跟踪、自动收费、移动车辆识别等;433 MHz产品为有源产品,工作方式同微波产品。     

基于RFID和ZigBee的嵌入式电子生猪秤设计

为满足生猪养殖高度智能化和自动化的需求以及养猪物联网技术的应用,设计了一种基于RFID和ZigBee的嵌入式电子生猪称重综合系统.该电子秤可以实现生猪的自动称重、电子标签识别和称重信息的无线数据传输.介绍了系统实现的原理、单元模块和软件实现,重点阐述了电子秤数据采集电路、电子标签识别和无线数据传输的设计方法.     

前车干扰对ETC系统传播损耗的影响

车载通信系统通过车-车、车-路通信将人、车、路及环境有机结合,提高了交通系统的安全和效率。电子不停车收费系统(ETC)作为车-路通信的典型应用,在国内外得到广泛运用。目前,单车道有障碍应用模式ETC道路通行效率较低,为提高车辆通行效率,出现了多车道自由流(MLFF)模式,多台车辆可同时进入同一收费区域,自前车可能干扰后车通信。通过射线跟踪技术和一致性绕射理论,讨论了MLFF模式中路侧单元(RSU)→轿车→轿车情形下的前车干扰路径传播损耗模型,其次在仿真环境下分析了RSU与车载标签单元(OBU)距离以及OBU与前车距离的变化对传播损耗的影响,最后进行了现场测试,测试结果表明,所提出的路径损耗模型是有效的。     

超高频射频识别读写器设计

超高频射频识别系统具有读写速度快、存储容量大、识别距离远和可同时读写多个电子标签等特点,已经在物流等众多领域得到越来越广泛的应用.为了满足应用的需要,本文通过分析ISO 18000-6B标准中读写器的特性,提出了超高频射频识别读写器的解决方案,重点阐述了读写器的设计结构、工作流程,以及相关部分的设计.实际应用结果表明,该读写器基于ARM微处理器,具有读写速度快(单个标签64 bit/6 ms)、识别率高、识别距离远(≥6 m)等优点,能够满足应用需求.     

电能计量设备的电子封印系统的手持终端开发

介绍了基于无线射频技术的电子标签,以RFID技术为手段,以Windows CE系统的PDA为平台,以C＋＋为编程语言,开发了电子封印管理系统所需的手持设备软件,并进行了测试。试验证明,该手持设备满足电子封印管理系统的功能要求。     

箱式大批量射频识别方法的研究与应用

针对传统射频识别技术中存在的批量采集物品电子标签的漏读和误读问题,文章提出一种大批量识别电子标签的方法,可对采用射频标签的产品进行批量识别和数据采集。本方法采用屏蔽技术,防止了外界电器干扰和非法标签的绕射干扰,利用屏蔽装置内部射频识别的空腔效应,采用变化电磁场的方法,通过多路径绕射,去识读直线遮挡电子标签物品,减少了遮挡盲点和叠加盲点。射频天线采用独立运行模式,传动模组利用驱动器和控制器控制天线位置和角度,实现了电子标签的全部识读。     

基于无线射频识别技术的自动导引车导航方法的研究

自动导引车是自动化物流系统、柔性生产组织系统的关键设备。为了克服自动导引车现有导航方法的某些缺点,设计了一种基于无线射频技术的导航方法。采用了无线射频识别技术与自动导引车的集成系统,通过无线射频系统中电子标签的配置和相应的导航算法,实现了精确导航。该方法已应用到实验室自动导引车的导航中,简化了导航系统,降低了成本。     

一种宽频带RFID阅读器天线的设计

UHF RFID标签在密集布放环境下,会由于标签天线间的互相影响,使工作频率发生偏移,造成系统漏读.因而本文设计了一款新型的圆极化阅读器天线,该天线工作在UHF频段,具有小型化、高增益、宽频带的特点.其中主辐射圆形贴片通过4个探针与微带匹配网络上下相连,匹配网络的引入提高了天线的圆极化轴比和工作带宽.仿真结果表明,该天线在UHF频段的阻抗带宽和3 dB轴比带宽分别为13％和5％,增益高达9.4 dBi.在空旷的环境下,对密集布放的多个RFID标签进行读取测试.实验表明,运用宽频带的RFID阅读器天线可以有效地提高标签的读取率.     

列车辅助定位系统的设计

城市轨道交通的运行主要是依靠信号系统,作为机电系统,不可避免会发生故障,在信号系统出现故障时,对行车会产生安全问题。在信号系统失效,工作人员采用人工方式控制列车运行情况下,利用无线射频(RFID)技术和红外技术,配合闭路电视监控(CCTV)系统,对列车进行定位和记录,使行车指挥人员了解列车位置、运行轨迹,从而为后续的列车运行指挥控制提供依据。从技术上和管理上,保障城市轨道交通的运行安全。     

Adaptive Power Control Protocol With Hardware Implementation for Wireless Sensor and RFID Reader Networks

The development and deployment of radio frequency identification (RFID) systems render a novel distributed sensor network which enhances visibility into manufacturing processes. In RFID systems, the detection range and read rates will suffer from interference among high-power reading devices. This problem grows severely and degrades system performance in dense RFID networks. Consequently, medium access protocols (MAC) protocols are needed for such networks to assess and provide access to the channel so that tags can be read accurately. In this paper, we investigate a suite of feasible power control schemes to ensure overall coverage area of the system while maintaining a desired read rate. The power control scheme and MAC protocol dynamically adjust the RFID reader power output in response to the interference level seen during tag reading and acceptable signal-to-noise ratio (SNR). We present novel distributed adaptive power control (DAPC) as a possible solution. A suitable back off scheme is also added with DAPC to improve coverage. A generic UHF wireless testbed is built using UMR/SLU GEN4-SSN for implementing the protocol. Both the methodology and hardware implementation of the schemes are presented, compared, and discussed. The results of hardware implementation illustrate that the protocol performs satisfactorily as expected.     

RFID系统动态仿真测试技术的研究

本文通过对影响RFID系统工作性能的实际应用环境中关键因素的分析建模,介绍了利用电子设备模拟实际工作现场的情况和动态信号特征设计RFID测试系统的方法.以铁路车号自动识别系统中地面读出设备动态仿真测试平台的设计为例,介绍了该方法的实现过程.利用该方法设计的地面读出设备动态综合测试系统可以通过参数设置和软件控制,方便地实现对各种典型测试场景的模拟,为铁路车号自动识别设备的研制和生产提供了方便有效的测试手段.     

Practical Minimalist Cryptography for RFID Privacy

The fear of unauthorized, hidden readouts has dominated the radio frequency identification (RFID) privacy debate. Virtually all proposed privacy mechanisms so far require consumers to actively and explicitly protect read access to their tagged items-either by jamming rogue readers or by encrypting or pseudonymizing their tags. While this approach might work well for activists and highly concerned individuals, it is unlikely (and rather undesirable) that the average consumer should be outfitted with RFID jamming devices before stepping outside, or that anyone would bother pseudonymizing every can of soda they buy with a personal PIN code. Juels' ldquominimalist cryptographyrdquo offers a simple, yet effective, identification and tracking protection based on simple ID rotation, but it requires that the corresponding mappings (i.e., from pseudonyms to real IDs) are electronically exchanged whenever a product changes hands (e.g., for buying a pack of chewing gum at a kiosk)-a rather impractical requirement. Our work extends Juels' concept in order to alleviate the need for passing ID mapping tables. Using carefully assembled sets of IDs based on the cryptographic principle of secret shares, we can create RFID tags that yield virtually no information to casual ldquohit-and-runrdquo attackers, but only reveal their true ID after continuous and undisturbed reading from up-close-something that can hardly go unnoticed by an item's owner. This paper introduces the underlying mechanism of our extension to Juels' proposal, called ldquoShamir Tag,rdquo analyzes its tracking resistance and identification performance, and discusses deployment aspects.     

Microwave Surfing: Has your cat gone phishing?

A radio frequency identification (RFID) system has two parts: a (usually portable) reader and a tiny transponder (radio tag, RFID chip), which is embedded in or attached to the tracked object (such as a piece of baggage on an airport conveyor belt or a pet). Researchers from Vrije Universiteit in Amsterdam demonstrate in [3] how these tiny RFID tags can be used to spread malicious computer code. Since the tags have a very limited memory (typically less than 1,024 b), it had been generally assumed that they were unsuitable vectors for introducing viruses into computers connected to RFID readers [4].     

基于RFID的变电站巡检系统

摘要：传统的变电站巡检方式由于其固有缺陷越来越不能满足变电站管理信息化和规范化的要求。提出了一种基于RFID技术的变电站巡检系统。该系统采用具有RFID读写器的PDA作为巡检器,应用RFID技术、GPRS无线通信技术和嵌入式数据库技术,可以方便地记录电力设备的到位情况和缺陷信息,解决了传统巡线方案中存在的人员到位困难和巡检数据不及时等问题,该巡检系统在电力巡检中有良好的推广使用价值。     

基于PUF和LED密码算法的轻量级RFID安全认证协议

无线射频识别技术是目前推动物联网发展的重要技术之一,具有不易涂抹,成本低廉等优势。由于无线射频信号在传输过程中易收到攻击,RFID系统需要建立完善的完全保障机制。本文基于RFID系统的安全要求和技术现状,提出了一种轻量级RFID安全认证协议,该协议基于LED密码技术和物理不可克隆函数,利用PUF的挑战-响应信号对进行身份验证,LED算法对PUF的响应信号进行加密传输保证认证信息安全,每次认证结束后都会更新服务器内的标签信息。本文使用Verilog语言对认证过程进行电路实现与仿真,并基于40nm平台的标准单元库对电路进行综合分析。仿真和综合结果表明该轻量级RFID安全认证协议可有效抵御常见攻击,并且标签存储、计算的硬件开销都较低,适用于资源受限的场景。     

RFID Technologym - Are You Ready for It?

In this paper, the technical considerations and broad business implications of RFID are focused. The basic RFID hardware elements are tags and readers. The data exchanged between these two elements may be encrypted or processed as needed. From a technical point of view, the challenges in designing an RFID tag are many. Silicon technology can deliver the required circuit performance at low cost and high volume and efforts are made to design a system on chip (SOC) at RF frequency.     

Design of a novel adder‐less Barker matched filter for RFID

Radio frequency identification (RFID) is the utilization of the radio frequency for the purpose of identification. RFID is lagging behind due to vendor specific solutions and excessive implementation cost. A Wireless Fidelity (WiFi) compatible IEEE 802.11 RFID tag can overcome these limitations. IEEE 802.11 utilizes Direct Sequence Spread Spectrum (DSSS) technique and a matched filter is a vital block in a DSSS system. A low‐power and low‐area novel adder‐less Barker matched filter is proposed in this paper by eliminating the conventional multiple multiplications. The matched filter designed in 0.18 µm CMOS technology achieves average and maximum power consumption of 33.747 μW and 8.08 mW, respectively and chip area of 0.41184 mm² only. The simulation result shows the correct matching of data against the threshold value. Compared with the conventional matched filter, the design achieves 25% power reduction (maximum power) and 51% chip area reduction. Therefore, the design will help to implement a low‐power matched filter for IEEE 801.11 compatible RFID tag. Copyright © 2013 John Wiley & Sons, Ltd.