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射频识别动态定位方法 总被引:1,自引:0,他引:1
提出一种新型的通过参考标签和移动RFID射频读写器进行定位的方法。该定位方法的主要优点是不需要记录任何测量信息如TOA、RSSI等,而是通过移动读写器,不断对目标标签和参考标签进行读取,经椭圆还原算法对读区域进行还原,最终以交集计算实现定位。该方法思路简单,但实现了较高精度的RFID室内定位。实验结果表明,该定位方法的精度可在最小的参考标签单元格内(可到达数十厘米级)。同时建立的原型定位系统具有成本低、易于部署等特点,存在应用于大规模RFID仓储定位管理的可行性。 相似文献
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本文提出一种基于RFID传感标签和深度信念网络(Deep belief networks, DBN)的人体活动识别技术。首先,设计了一种无源RFID(Radio frequency identification,RFID)传感标签,人体加速度信号存入传感器数据区,标签序列号和硬件版本组成了标签ID可以进行唯一标识。然后从数据中提取初始特征,采用核主成分分析(KPCA)和线性判别分析(LDA)对特征进行进一步处理,使其更具鲁棒性,有利于快速的人体活动识别。最后,利用这些特征训练DBN。在一个可穿戴传感器数据集上进行实验,仿真结果表明,所设计的传感标签最小灵敏度约为-17dBm,对应在2W的阅读器功率下传感标签最大工作距离为10.5m;所提出的DBN算法优于其他算法,也极大的提高了识别准确率。 相似文献
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RFID(Radio Frequency Identification)射频识别系统中,如何在识别标签基本信息的基础上进一步精准地感知标签的实时位置一直是一个重要问题.本文首次提出一种基于二维相控阵天线的非测距RFID标签定位方法(Phased Array based Range Free Tag Localization,PATL).该方法利用相控阵天线辐射波束角度可调的特点,对搜索平面依次进行扫描,并通过统计不同天线区域内标签出现的次数,利用加权算法给出标签的二维位置.该方法能够在不借助参考标签或辅助设备的前提下对多个目标标签进行实时定位.通过利用一款集成有相控阵天线的商用超高频RFID阅读器对方法进行了实验验证.结果表明,算法的定位精度能达到21cm. 相似文献
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提出了一种基于PIC16F877A微控制器和CC2500射频收发器芯片的低功耗、低成本RFID(Radio Frequency Identification,无线射频识别)局域定位系统设计方法,介绍了系统的定位工作原理、主要硬件电路模块及定位算法的设计和实现。采用基于序列号对时隙数运算的排序算法有效解决了多标签识别碰撞的问题,基于射频辐射强度(Received Signal Strength Indication,RSSI)和圆周定位算法实现了基于RFID多标签系统的平面定位。实验测试表明,这种射频定位方法能够实现一定精度下的无线局域定位的功能。 相似文献
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RFID标签(无线射频系统)已在许多领域推广应用。在RFID标签制作中,蚀刻法是常见的一种制作方法。文章主要介绍凹印蚀刻制作RFID标签天线的技术要领。 相似文献
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V. F. Dmitriev A. S. Koigerov 《Journal of Communications Technology and Electronics》2011,56(10):1256-1265
A realization of the method of correlation signal processing for solving problems of collisions in radio frequency identification
(RFID) systems using RFID tags is considered. The reflecting structures of RFID tags are fabricated in the form of surface
inhomogeneities with typical dimensions of several tens of nanometers. An algorithm for the search of codes for SAW RFID tags
and a method for calculating the SAW RFID tags with phase-shift keyed codes are proposed. Modeling and experimental study
of SAW RFID tags designed for formation of signals with phase-shift keyed codes possessing specified correlation properties
are performed. Oscillograms of signals formed by the RFID tags are presented, and their correlation properties are studied. 相似文献
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声表面波射频识别系统应用前景广阔,选择结构简单、解码可靠的声表面波标签识别方法十分重要。分析比较了基于IQ解调和功率检波两种不同技术的声表面波标签识别方法,基于功率检波技术的识别方法更具优势。设计制作了基于功率检波技术的阅读器,在测试了阅读器关键元件对数功率检波器静态性能和动态性能的基础上,结合声表面波标签进一步验证了阅读器识别标签编码的能力。实验结果表明,采用功率检波技术可以实现声表面波标签编码的准确识别,且阅读器电路结构更简单,成本更低。 相似文献
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Passive surface acoustic wave (SAW) tags require a large signal-to-noise ratio (SNR) in order to increase the interrogation range. For the purpose of achieving high SNR for radio frequency identification (RFID) communication systems, Barker codes, a binary phase shift keying (BPSK) modulation technique, have been adopted in this study. Passive SAW RFID tags were designed with 5-bit Barker code sequences to generate BPSK modulated signals. Through the SNR analysis, the improvements in SNR were about 11?dB using Barker codes along with a correlator, which can be further improved by optimisation in the correlator. 相似文献
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识别和定位是用于室内服务的关键信息,常见方法是估计RFID标签的位置。而在室内环境下,信号遭受严重的损耗,标签的性能也会受到一定的限制。针对这些问题,文中对现存的RFID定位技术和定位原理加以总结,在对RFID定位技术进行阐释和分类分析的基础上,讨论了在此领域的未来发展趋势。 相似文献
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论述了基于DSP技术的声表面波射频识别(SAW RFID)阅读器的设计方法.在此基础上给出了阅读器的硬件设计和与多个标签识别的流程图.最后对标签的反碰撞问题进行了研究. 相似文献
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声表面波射频识别无源电子标签 总被引:2,自引:0,他引:2
简述声表面波射频识别无源标签的原理与特点,介绍了434 MHz和915 MHz标签的试验结果:工作频率915 MHz、434 MHz,码容量>1 000,读写距离0.5~5 m。讨论了声表面波标签研究过程中的一些技术关键。 相似文献
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消防员在地下建筑、无窗建筑、大型建筑物内,执行火情控制与人员搜救时,不可避免会遇到浓烟、黑暗、高温、陌生等情况,因此就需要精确的室内定位系统支持,已有的室内定位技术无法满足定位精度和长期部署的需求.本文提出了一种基于无源射频识别(RFID)标签的消防员室内定位系统,通过在消防员头盔内安装可变功率的RFID读写器,并将建筑物内读取的已经过精确标定的RFID标签信息回传到远程服务器进行计算处理,可实现建筑物外指挥员对室内消防员的实时精准定位和指挥功能. 相似文献
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Piramuthu S. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2008,38(3):360-376
The explosion in recent interest in radio-frequency identification (RFID) tags stems primarily from advances in information processing in supply chain management. Given their processing power and memory capabilities, RFID tags can be used in a wide range of applications including those where barcodes can and cannot be used. Although the potential exists, it is hampered by the relatively high unit cost of implementation and issues related to privacy and security. As with any technology, unit cost of RFID tags and their related systems is bound to come down. As for security and privacy issues, the main impediments are limited processing power, memory, and external power to operate these tags. In spite of these resource constraints, recent years have seen a plethora of new authentication protocols that promise to alleviate security and privacy concerns associated with the use of RFID tags. We evaluate a few protocols that have been suggested for use in passive RFID-tagged systems and identify vulnerabilities that may be present. When appropriate, we present modifications of existing protocols to prevent identified vulnerabilities. 相似文献
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Vassilis Gikas Constantinos Antoniou Guenther Retscher Athanasios Panagopoulos Allison Kealy Harris Perakis 《Journal of Location Based Services》2016,10(4):241-261
A relatively low-cost system for indoor parking facilities management is proposed, which is a combined solution of RFID/WiFi and a MEMS IMU monitoring scheme. An RFID localisation module is proposed in the form of so-called virtual gates. To define such virtual gates, either RFID tags or readers are placed at known locations throughout the area of interest. In this study, a number of tags are fixed at known positions and a moving reader is carried by each participating vehicle. Based on this configuration set-up, the Cell of Origin (CoO) technique is applied, in which the system indicates the presence of the user carrying the reader in a cell around the tag location. To define a virtual gate, tags are installed along the parking lot corridors and at critical transit passages in the parking facility. The CoO technique is also proposed in the case of WiFi for location determination of vehicles in a multi-storey car park. In this study, WiFi is employed to monitor the passing vehicles and bridge the gap until a tag can detect a user’s reader again. Thus, a combined positioning solution of RFID and WiFi is achieved. As a complement to the proposed RFID/WiFi system, this study examines the potential and limitations of MEMS IMU sensors (i.e. accelerometers, gyroscopes and barometers) commonly found in modern smartphones. The paper concludes with a detailed discussion on the implications of alternative positioning techniques for indoor parking management. 相似文献