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1.
多个应答器的碰撞问题是影响超高频射频识别(RFID)系统读取效率的一个关键问题。从EPC Class1 Generation2(C1G2)RFID系统帧长受约束特点出发,分析了帧时隙ALOHA防碰撞机制及其经典应答器估计方法的特点。提出了应答器间隔估计方法(IEM)以及基于该方法的EPC C1G2 RFID防碰撞算法,并给出了仿真结果。与现有基于经典应答器估计方法的射频识别系统防碰撞算法相比较,提出的防碰撞算法减少了识别时间,提高了系统的识别效率。  相似文献   

2.
Presently the necessity of building anticollision RFID systems with dynamic location change of tags appear more often. Such solutions are used in identification of moving cars, trains (automatic identification of vehicles – AVI processes) as well as moving parts and elements in industry, commerce, science and medicine (internet of things). In the paper there were presented operation stages in the RFID anticollision system necessary to communicate with groups of tags entering and leaving read/write device interrogation zone and communication phases in conditions of dynamic location change of tags. The mentioned aspects influence RFID system reliability, which is characterized by the efficiency coefficient and the identification probability of objects in specific interrogation zone. The communication conditions of correct operation of multiple RFID system are crucial for efficient exchange of data with all tags during their dynamic location changes. Presented problem will be the base to specify new application tag parameters (such as maximum speed of tag motion) and synthesis of interrogation zone required for concrete anticollision RFID applications with dynamic location change of tags.  相似文献   

3.
一种基于现场总线的RFID互联系统研究与实现   总被引:2,自引:1,他引:2  
单个孤立的RFID系统已经不能满足现在的应用需求,依据射频识别系统特点和工作原理,提出了一种基于现场总线技术的RFID互联系统;在研究与实现阅读器射频识别、天线设计和通信功能基础上引入现场总线控制FC(FieldbusControl)技术,提出了基于CAN总线的阅读器节点互联模型,完成了RFID节点硬件电路、电磁兼容性以及应用层通信协议设计。实验表明系统能对各个节点数据进行充分交换和控制,达到了可靠性高、实时性强、扩展灵活、纠检错能力强、布线维护简单、高性价比的设计目标。  相似文献   

4.
Transmission Delay Line Based ID Generation Circuit for RFID Applications   总被引:4,自引:0,他引:4  
A transmission delay line based ID generation circuit is presented for radio frequency identification (RFID) applications. The ID generation circuit has been designed using microstrip transmission lines as delay lines for its operation at ultra high frequency (UHF: 915MHz). The layout has been realized on a flexible substrate using photolithography based fabrication techniques. The circuit has been tested with an on-off-key (OOK) modulated input signal and different combinations of 4bit ID code have been generated. Obtained results confirm the concept and its use in RFID applications  相似文献   

5.
苏健  杨晓娇  韩雨 《电子学报》2018,46(4):903-910
多标签碰撞问题严重影响射频识别RFID系统的识别效率.在研究子帧观测机制的基础上,针对常规动态帧时隙Aloha多标签防碰撞算法存在的复杂度高、时间效率低等问题,提出了一种基于子帧的动态帧时隙Aloha算法,其在识别过程中采取设定的子帧观测,运用空闲与碰撞时隙数的关系估计剩余标签数,再依据预估的结果优化设置新的帧长,显著提升了大容量多标签RFID系统的识别效率.该算法的运算复杂度低、计算量小,易于在常规RFID读写器中实现,工程应用前景广阔.仿真结果表明:同传统的Aloha类防碰撞算法相比,提出的算法具有复杂度低、稳定好、识别效率高等优势.  相似文献   

6.
Ultra-high frequency (UHF) radio frequency identification (RFID) system suffers from large leakage of the carrier due to insufficient TX-to-RX isolation. A narrowband leaking carrier canceller (LCC) for UHF RFID is proposed to enhance the isolation. Hardware realization is carried out based on simulation model in ADS (Advanced Design System). Measurement results indicate that the TX-to-RX isolation is improved from 20 dB to above 40 dB within UHF RFID frequency band of 920–925 MHz. Upper limit of increase in isolation versus amplitude and phase distortion are also presented and discussed.   相似文献   

7.
Collision and security issues are considered as barriers to RFID applications.In this paper,a parallelizable anti-collision based on chaotic sequence combined dynamic frame slotted aloha to build a high-efficiency RFID system is proposed.In the tags parallelizable identification,we design a Discrete Markov process to analyze the success identification rate.Then a mutual authentication security protocol merging chaotic anti-collision is presented.The theoretical analysis and simulation results show that the proposed identification scheme has less than 45.1%of the identification time slots compared with the OVSF-system when the length of the chaos sequence is 31.The success identification rate of the proposed chaotic anti-collision can achieve 63%when the number of the tag is100.We test the energy consumption of the presented authentication protocol,which can simultaneously solve the anti-collision and security of the UHF RFID system.  相似文献   

8.
Radio frequency identification (RFID) technology system is quickly evolved many applications to manage personnel can be more efficient for automation systems. We combine the RSA encryption and decryption algorithms to raise the safety and the information security systems. The RFID environment has been communicated to exchange data for heterogeneous wireless networks. In this paper, it is implemented the RFID-based campus system solutions to security and privacy of RFID system for wireless mesh network applications. We propose to enhance the security algorithm combined RFID devices for the antenna arrays system. This paper is also presented the integrated framework for the application and integration systems based on service oriented architecture, and given a specific application of the framework combined with campus system.  相似文献   

9.
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   

10.
声表面波(SAW)射频识别(RFID)技术是当前信息识别系统向无源无线发展的关键技术,在工业、国防及商业等领域有重要作用和广泛应用前景。该文探讨了SAW RFID技术原理及信息编码方案;综述了典型的SAW RFID产品及应用;提出了SAW RFID技术发展趋势,对推动SAW RFID技术发展和应用有重要意义。  相似文献   

11.
Over the past several years, significant improvements have been made in solid-state devices (that is, avalanche diodes, Gunn diodes, varactors, mixer diodes, etc.) that have enhanced the overall capability and low-noise performance of millimeter-wave receivers. With these improved devices, it is now possible to configure completely solid-state low-noise millimeter-wave receivers. As is similar in the microwave region, low-noise parametric amplifiers, broad-band low-conversion-loss mixers, and solid-state local oscillators are now available. Furthermore, cryogenically cooled parametric amplifiers and mixers are also being developed that will result in achieving the ultimate in system sensitivity. With the flexibility offered by these completely solid-state millimeter-wave components, it is now possible to design the optimum system configuration for the intended application whether it be an advanced communication system, a sophisticated EW application, a RADAR system, a radiometric system, or satisfying any of the numerous receiver requirements that are being evolved. This paper explores the trends that are being developed in the millimeter-wave region and their application to system design. The performance criterion of various receiver systems and their sensitivity requirements are presented. A review of the system operating noise temperature concept and the method by which it can be determined and its applicability to low-noise components is demonstrated. A review of the state-of-the-art of low-noise systems and experimental data obtained in the millimeter-wave region is also presented.  相似文献   

12.
This paper describes the application of a SAW multiplexer to develop range line resolution in FMCW millimeter-wave radar systems. The basic system design concept as well as test results are presented describing the function of the SAW multiplexer in developing the multiple-range cells in the millimeter-wave terminal guidance seeker. The SAW multiplexer has 16 channels and uses the offset multistrip coupler technique for sorting the acoustic beans into various acoustic tracks according to frequency.  相似文献   

13.
于广威  何文才 《通信技术》2010,43(4):106-108
RFID射频识别是一种非接触式的自动识别技术,它通过射频信号自动识别目标对象并获取相关数据,识别工作无须人工干预,可工作于各种恶劣环境。RFID技术可识别高速运动物体并可同时识别多个标签,操作快捷方便。首先简要介绍了RFID技术的概念、优势以及RFID系统的组成和工作原理。并提出了一种基于RFID技术的身份识别系统,并提出标签的存储防静态分析和存储数据的访问控制;以及读卡器和标签之间的认证和密钥协商协议的方案,以满足身份识别的要求。  相似文献   

14.
Due to the rapid acceptance of mobile devices and localisation technologies like global positioning system (GPS) in every day life, the fascination in utilising such technologies for entertainment is also increasing. The concept of urban gaming employs localisation technology to incorporate player's position into the game concept, generating a truly pervasive game experience. Urban gaming has immense potential and is often cited by denizens as the next gaming behemoth, however it is somewhat hampered by the existing technologies that it employs. GPS is the more commonly used technology in this genre; however it displays some serious limitations, especially in urban areas. This research investigates the feasibility of incorporating radio frequency identification (RFID) as an alternate technology in location-based urban gaming. RFID is an emerging and increasingly popular technology, whose versatile capabilities offer a wide range of possible uses. This article documents a middleware RFID-enabled location-based gaming prototype.  相似文献   

15.
A radio frequency identification (RFID) system is a special kind of sensor network to identify an object or a person using radio frequency transmission. A typical RFID system includes transponders (tags) and interrogators (readers): tags are attached to objects/persons, and readers communicate with the tags in their transmission ranges via radio signals. RFID systems have been gaining more and more popularity in areas such as supply chain management, automated identification systems, and any place requiring identifications of products or people. RFID technology is better than barcode in many ways, and may totally replace barcode in the future if certain technologies can be achieved such as low cost and protection of personal privacy. This paper provides a technology survey of RFID systems and various RFID applications. We also discuss five critical research issues: cost control, energy efficiency, privacy issue, multiple readers' interference, and security issue. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

16.
射频识别芯片TMS3705在汽车智能防盗报警装置中的应用   总被引:3,自引:0,他引:3  
介绍了以TMS3705为射频基站的射频识别系统 ,给出了其在汽车智能防盗装置中的应用工作原理、硬件组成 ,以及软件设计方法和软件流程 ;同时介绍了为提高识别可靠性而对TMS3705信息读取采用的16位循环冗余校验的具体算法。  相似文献   

17.
Radio frequency identification (RFID) is a wireless technology used in various applications to minimize the complexity of everyday life. However, it opens a large number of security and privacy issues that require to be addressed before its successful deployment. Many RFID authentication protocols are proposed in recent years to address security and privacy issues, and most of them are based on lightweight cryptographic techniques such as pseudo-random number generators (PRNGs), or bitwise logical operations. However, the existing RFID authentication protocols suffer from security weaknesses, and cannot solve most of the security and privacy problems. A new solution is necessary to address security and privacy issues. In this paper, an improved three-pass mutual authentication protocol (ITPMAP) for low-cost RFID tags is proposed to offer an adequate security level for RFID systems. The proposed ITPMAP protocol uses one PRNG on the tag side and heavy-weighted cryptographic techniques (i.e., digital signature and password-based encryption schemes) on the back-end server side instead of lightweight cryptographic techniques to address the security and privacy issues. The ITPMAP protocol is secure against various attacks such as cloning, spoofing, replay, and desynchronization attacks. Furthermore, as a proof of concept, the ITPMAP protocol is adopted to propose the design of three real-life RFID systems; namely: Signing and Verification of Graduation Certificate System, issuing and verification of e-ticketing system, and charging and discharging of prepaid card system. The Unified Modeling Language is used to demonstrate the design of the proposed ITPMAP protocol and systems. Java language is used for the implementation of the proposed systems. In addition, the “Mifare Classic” tags and readers are used as RFID apparatuses for the proposed systems.  相似文献   

18.
RFID系统中有限的标签芯片资源,导致数据与信息的安全成为RFID系统的重要问题之一,散列函数的单向性为RFID的识别和认证提供了一种既可靠又有效的途径.在分析了现有几种典型散列认证协议的基础上,提出了一种新的基于散列函数的安全认证协议.本协议旨在解决手持式、无线连接的RFID阅读器与标签、服务器间的识别,利用散列函数实现服务器、阅读器以及电子标签三者之间的相互认证.经过安全性与性能的分析,新协议在采用较小的存储空间和较低的运算开销的情况下,可抵抗已知的大多数攻击,有效地保证了RFID系统中数据和隐私的安全,实现了终端与服务器间的双向认证和匿名认证,非常适合于在大型分布式系统中使用.  相似文献   

19.
The basic concept and features are presented of double-sided microwave integrated circuits (double-sided MICs), which effectively utilize various kinds of transmission lines on both sides of a substrate. The fundamental circuits such as 180° hybrids (magic Ts) and many application circuits described here are very useful in developing microwave and millimeter-wave band equipment. The concept of the double-sided MIC technique is also suitable for application to monolithic MICs  相似文献   

20.
Internet of Things (IoT) is a new vision of the future technological ubiquity in ubiquitous computing, which becomes the mapping from the real world to the digital one. Radio frequency identification (RFID) technology is a key enabler of the future IoT and it has a great economical potential. However, the RFID system uses of Electronic Product Code (EPC) tags can drastically threaten the security of applications. With the widespread use of RFID technology, its security problems become the hot topic in the academic and industrial fields. Aiming at the RFID network's security problems, we propose a novel P2P based RFID network architecture (P2P-RFID), and analyze the security problems in this kind of network. And a feasible and scalable protocol to guarantee P2P-RFID network security is also presented in this paper. The proposed protocol uses P2P storage technology together with the utilizing of asymmetric encryption algorithm (RSA) based authentication. An analysis proves that the presented protocol is secure. Moreover, the protocol authentication does not require a Certificate Authentication (CA) database, which avoids the single-point bottleneck.  相似文献   

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