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关键词： Batteryless sensors   Lithium ion battery safety   Radio frequency identification   Thermal runaway detection   Ultra high frequency   Wireless temperature sensor  

摘要： This study introduces a novel approach to enhance fire protection in aircraft cargo compartments, motivated by the urgency to address catastrophic in-flight fires recorded between 2006 and 2011. The method uses ultra-high frequency (UHF) radio frequency identification (RFID) temperature sensing tags and advanced algorithmic analysis to enhance fire detection capabilities within unit load devices (ULDs). This approach significantly reduces detection times while minimizing false *** first objective was to create an economical, battery-free fire detection system with UHF RFID temperature sensing tags installed within ULDs. This positions the temperature sensing tags closer to potential fire sources than traditional cargo compartment ceiling-mounted smoke detectors. Wireless temperature sensing tags allow the ULDs to move in and out of aircraft. Passive sensors address the challenges of battery-powered systems, such as battery changes and thermal runaway *** second objective sought to enhance the RFID-based system with near real-time temperature monitoring capabilities within ULDs. The system provides accurate temperature trend analysis by incorporating a moving average convergence divergence (MACD) algorithm adapted from financial markets. This significant advancement improves fire detection times and supports communication of conditions within ULDs to flight crews, enabling quicker response *** third objective aimed to reduce false alarms through an algorithm capable of identifying significant temperature differences between separate ULDs. To achieve this, RFID temperature sensors were installed across all ULDs for continuous environmental monitoring. Under normal conditions, only minimal temperature variance is expected among ULDs. However, if the system detects a notable temperature differential between any two ULDs, it issues an alert. This method enhances the accuracy of fire detection while significantly reducing the likelihood of false alarm

关键词： RFID   本体知识   整车制造   全流程追溯  

摘要： 在全球汽车制造业竞争日益激烈的环境中，保障产品质量、提升生产效率、加强供应链管理以及提升客户满意度已经成为汽车企业持续发展的关键。传统的制造追溯系统往往存在信息孤岛、数据不一致及追溯效率低下等问题。本文深入探讨了将RFID技术与本体知识库相结合设计的系统架构，分析技术融合与实现的方式，提出系统具体应用方面的见解，并对该系统的实施效果进行评估。

关键词： RFID protocol   UMAPs   mutual authentication   low-cost RFID tags   replay attacks   security analysis  

摘要： The most recent ultra-lightweight mutual authentication protocol (UMAP) adopts a mechanism for key updating to keep the security forward and backward. The back-end server updates the secret keys immediately after sending the final message. Certainly, an adversary can intercept the final messages so that the back-end server updates the secret keys while the RFID tag does not. The replay attack can send the last messages by continuing to render the back-end server and RFID tags unauthorized. The major problem faced by existing protocols, when using high cryptographic operations on low-cost RFID tags, requires more memory, and computational power makes them unusable for these types of tags. In addition, there are weaknesses in the design of the existing protocols that lead to the emergence of desynchronization, secret disclosure, and replay attacks. Therefore, this paper proposes the design and development of an ultra-lightweight mutual authentication protocol that overcomes the weaknesses in earlier protocols and builds by implementing the rotation operator, mechanism of the secret keys, T-function, and timestamp technique. The informal and formal analysis results using security protocol verification official tools (Scythe and AVISPA) show that the proposed protocol has the ability to prevent attacks, especially replay attacks. Experimental analyses of our protocol to measure the performance shows that the proposed protocol involves a lower overhead than previous protocols. The total execution time in milliseconds of the processes of the proposed protocol with the existing protocols is 0.031ms, and it achieves an average of 78.51% over other protocols. In addition, this paper provides a comparison with the most recent protocols on performance, privacy and security requirements. Our proposed protocol storage space requirement is lowest than the existing protocols, the cryptographic requirement is ultra-lightweight and efficient and shows that the communication messages

摘要： Objects made of metal are not randomly made out of this material, but because they must be accordingly resistant due to use and environment. Their labeling with conventional barcode labels is subject to high wear and tear, which can quickly lead to problems of identifiying the parts. A remedy is provided by RFID labels which are especially designed for use on metals and which make possible a permanently reliable labeling and identification of metallic objects.

关键词： 无源UHF RFID标签   模拟前端电路   数据读取电路   低功耗  

摘要： 近年来,物流、零售等行业的快速发展对电子标签的识别距离和设计成本提出了更高要求,在各类电子标签中,无源UHFRFID标签凭借其成本低、识别距离远、多对象同时识别的优势成为这些大规模应用领域的最佳选择。无源UHF RFID作为被动式的非接触识别技术,其标签芯片的工作能量全部来自于读写器发射的射频载波,则标签芯片的功耗便成为制约其识别距离的主要因素。因此,对无源UHF RFID标签芯片展开低功耗研究具有十分重要的意义。 为了满足大规模应用场景对电子标签的要求,本文研究了用于无源UHF RFID标签芯片的低功耗模拟前端电路和基于反熔丝型OTP存储器的低功耗数据读取电路,在保证标签芯片稳定工作的同时降低了电路功耗,进而提升标签的识别距离和整体性能。 对于低功耗模拟前端电路,研究主要集中在以下几个方面。第一,利用亚阈值技术和有源电阻技术设计了一款低压低功耗基准源电路,该电路在1.2V的典型工作电压下,仅以232nW的静态功耗即可实现所需基准电压,且其低频处的PSR优于-69dB,在降低功耗的同时有效兼顾了精度和面积要求。第二,设计了一款低静态电流LDO电路,通过采用工作在亚阈值区的一级运放作为误差放大器,将静态功耗降低至420nW,并利用二极管连接型PMOS管代替大的反馈电阻,有效减小了电路面积,从而降低标签芯片成本。第三,提出了一种基于可控延迟单元和信号保持单元的高可靠性上电复位电路,其在缓慢上电、快速上电、小电源纹波和大幅度掉电等情况下,均能够正常输出有效复位脉冲,且静态电流仅为81nA,在保证低功耗的同时进一步提高了复位信号可靠性。第四,设计了一款低功耗弛豫振荡器,其利用NMOS管的阈值电压取代了传统弛豫振荡器中复杂的比较器单元,将电路功耗降低至664nW,并通过温度补偿电路和开关电容自校准电路克服了因温度或工艺变化造成的时钟信号偏差,使输出时钟频率精度可达到2.34%,兼顾了标签芯片低功耗与高稳定性的设计要求。从整体来看,模拟前端电路功耗仅为1.4μW,版图面积为60μm×150μm,具有功耗低、面积小和稳定性高的特点。 对于低功耗数据读取电路,本文采用基于预充电机制的电压型灵敏放大器作为其核心单元,利用严格的时序控制信号即可对反熔丝型存储单元进行有效读取,避免了额外参考电流的存在,显著降低了电路功耗。此外,在低功耗灵敏放大器研究的基础上,完善了数据读取通路中的其他模块设计,并利用不同电阻值来模拟存储单元编程前后的不同状态,对完整的低功耗数据读取电路进行了相应仿真验证。后仿真结果表明:在读取频率为160kHz的情况下,所设计的数据读取电路平均功耗仅为3.6μW,相较于以电流型灵敏放大器为核心的传统读出电路,功耗优化率可超过50%。 本文深入研究了应用于无源UHF RFID标签芯片的低功耗模拟前端电路以及低功耗数据读取电路,并基于UMC110nm工艺完成了相应的原理图设计、版图绘制以及仿真验证,为实现RFID标签的大规模应用奠定了坚实的基础。

关键词： RFID tags   Backscatter   Switches   Impedance   Wireless communication   Thermal noise   Standards   Modulation   backscatter   RFID   Johnson noise   modulated noise   thermal noise  

摘要： In this work, we demonstrate that it is possible to read UHF RFID tags without a carrier. Specifically, we introduce an alternative reader design that does not emit a carrier and allows reading RFID tags intended for conventional carrier-based systems. While traditional RFID tags modulate a carrier, it is important to note that a modulation circuit used for backscatter also modulates the inherent noise of the tag circuitry, including the Johnson noise, irrespective of whether a carrier is present or not. Our Modulated Noise Communication (MNC) approach leverages recent work on Modulated Johnson Noise (MJN) and can be read by an alternative RFID reader design that enables simpler, more accessible RFID readings than a conventional backscatter reader by eliminating self-jamming obstructions. MNC is shown to support wireless transmission of data packets between 2 cm to 10 cm of separation between a standard UHF RFID tag and the proposed alternative reader for data rates of 1 bps and 2 bps.

关键词： 物联网   智能物流仓储   射频识别技术   自动导向车  

摘要： 随着物联网前沿技术的蓬勃发展,各行各业都在大力发展并采用物联网技术来实现生产和办公效率的提高以及人工成本的减少。针对物流行业和生产制造业而言,基于物联网技术下的物流仓储智慧化应用场景正逐步走进人们的视野。本文主要通过研究智能物流仓储市场发展趋势,以及对物联网技术和智能设备在智能物流仓储场景中的应用现状进行分析,从而深入剖析基于物联网技术下智能物流仓储应用的发展方向,以积极推动物流仓储系统智慧化建设为目标,进一步完善物流仓储的自动化、数字化应用模式。

关键词： 物联网RFID   防碰撞识别   应急救援装备管理  

摘要： 近年来我国各类重大灾害事故频发,严重威胁着人们的生命财产安全。面对多样化的灾害事故,产生了大量种类繁多的现代化应急救援装备,对应急救援装备管理系统的要求越来越高。当前应急救援装备管理系统仍存在感知层缺乏装备关键信息检测、仓储出入库管理效率低以及系统平台管理流程不完善等问题。基于上述背景问题,本文深入调研了多类应急救援装备的应用过程,开发基于物联网RFID的应急救援装备管理系统,实现对应急救援装备的智能化管理过程。论文主要工作内容如下: (1)研究基于低功耗优化策略的系统感知层关键技术。针对便携式剪切器装备智能化程度较低的问题,研究了装备使用过程中关键信息智能感知技术,采用GPS、RFID、NB-IoT、温度传感器等技术,开发装备自身状态、定位信息、过载自保护等模块化低功耗嵌入式子系统;针对感知层终端的低功耗需求,提出基于周期性任务调度算法的低功耗优化策略,完成对救援装备自身状态、应用定位等关键信息检测。 (2)改进了基于动态帧时隙ALOHA的RFID防碰撞算法。针对救援装备仓储出入库管理过程在同时检测大量装备时会出现系统识别效率低和功耗增高的问题,在深入研究动态帧时隙ALOHA算法的基础上,采用BP神经网络模型对该算法中标签估算方法进行改进以代替原有标签估算方法,提出了一种可兼容现有ISO18000-6C协议的新型动态帧时隙ALOHA算法,利用matlab进行多次仿真实验验证了改进后算法的有效性,并将算法部署到嵌入式系统中。 (3)设计并实现了基于物联网RFID技术的应急救援装备管理系统。调研当前应急救援装备管理模式,分析并确定管理系统的功能需求,设计系统管理平台的功能架构和逻辑架构;建立基于阿里云的物联网数据平台,完成对救援装备多种数据的无缝接入、实时监测和远程控制;开发系统管理平台,设计用户管理、装备信息管理、装备使用管理、文档管理等系统模块,实现对应急救援装备采购、出入库、维护、使用、报废的全流程管理。 最后进行了系统功能测试和性能测试。结果表明,基于物联网RFID技术的应急救援装备管理系统实现了对应急救援装备的全流程动态监控和设备精细化管理,系统负载性能、响应速度、感知层装备功耗等指标符合设计需求,整体达到预期效果。

关键词： 射频识别   收发分离式RFID系统   组网部署优化   防碰撞算法  

摘要： 物联网以实现万物互联为目标,近年来发展迅速并广泛应用。其中,以射频识别(Radio Frequency Identification,RFID)技术为代表的无源物联网系统具备低成本、低功耗、自动化、大容量等优势,受到产学研用各领域的广泛关注。然而,随着应用规模的不断扩大,现有的无源RFID系统的通信距离短、标签接入容量小、可扩展性差等痛点问题逐渐凸显,这限制了无源RFID技术的进一步推广应用。与传统RFID技术相比,收发分离式超高频RFID系统由于采用“接收器-激励器-标签”三点式架构,能够大幅提升通信距离、抑制自/互干扰、增大覆盖范围、提高标签接入容量,成为了无源物联技术研究的重点和热点。为了进一步支持大规模组网部署、增大系统覆盖范围、提升接入容量及自动化管理效率,本文开展收发分离式超高频RFID系统组网和系统效率优化技术研究,主要工作和特色总结如下: (1)研究并提出了收发分离式超高频RFID系统组网部署规划方法。在指定区域内,以系统最大化覆盖率和最小化干扰为目标,结合粒子群优化算法、遗传算法与去冗余算法计算求解部署方案,实现接收器和激励器部署位置、数量最优化,求解算法与经典粒子群优化算法和遗传算法相比,优化效果明显提升。 (2)研究并设计了收发分离式超高频RFID系统组网控制协议。在时频空多域分集技术的基础上,研究设计了基于单接收器-多激励器以及多接收器-多激励器的超高频RFID高效组网控制协议,协同降低接收器、激励器等设备间的互扰,通过单接收器-多激励器、多接收器-多激励器之间的高效调度控制与并行工作,实现组网成功率的大幅提升、组网规模的倍升。 (3)研究设计了收发分离式超高频RFID系统组网效率优化算法。面向收发分离式超高频RFID系统大规模标签接入场景,研究大规模标签分组机制和基于子帧观测及帧分解相结合的改进型的DFSA算法。其能够突破传统DFSA算法36.8%的系统吞吐率瓶颈,有效提升标签接入效率。 本文研究研究的收发分离式超高频RFID系统组网以及效率优化技术,为收发分离式系统的实现和应用提供了解决方案,具备良好的工程应用参考价值。