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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Tag-collision resolution techniques for RFID systems.

January 2007 (has links)
Nie, Jing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 73-77). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (Chinese Version) --- p.iii / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Technology Overview --- p.4 / Chapter 2.1 --- History --- p.5 / Chapter 2.2 --- RFID Systems --- p.7 / Chapter 2.2.1 --- Tag --- p.8 / Chapter 2.2.2 --- Reader --- p.10 / Chapter 2.2.3 --- Software system --- p.12 / Chapter 2.2.4 --- Communication infrastructure --- p.13 / Chapter 2.3 --- Frequency Regulations and Standards --- p.13 / Chapter 2.3.1 --- RFID frequency --- p.13 / Chapter 2.3.2 --- Standards --- p.14 / Chapter 2.4 --- Technology Comparison and RFID Applications --- p.16 / Chapter 2.4.1 --- Technology Comparison --- p.16 / Chapter 2.4.2 --- RFID Applications --- p.19 / Chapter 3 --- Research Background --- p.22 / Chapter 3.1 --- Tag-Collision Resolution Techniques for RFID systems --- p.23 / Chapter 3.1.1 --- Deterministic Collision-Resolution Technique --- p.25 / Chapter 3.1.2 --- Stochastic Collision-Resolution Technique --- p.27 / Chapter 4 --- Optimized Anti-Collision Protocol --- p.30 / Chapter 4.1 --- System Description --- p.31 / Chapter 4.2 --- Mathematical System Model --- p.35 / Chapter 4.3 --- Optimal Parameter --- p.40 / Chapter 4.3.1 --- Stochastic Shortest Path --- p.41 / Chapter 4.3.2 --- Optimal Parameter --- p.44 / Chapter 4.4 --- Performance Evaluation --- p.45 / Chapter 4.4.1 --- Initial and Optimal Policy --- p.45 / Chapter 4.4.2 --- Performance Comparison --- p.48 / Chapter 4.5 --- Summary --- p.53 / Chapter 5 --- Unknown Tag Set Anti-Collision Protocol --- p.54 / Chapter 5.1 --- Protocol Description --- p.55 / Chapter 5.1.1 --- System Model --- p.55 / Chapter 5.1.2 --- Tag Estimation --- p.57 / Chapter 5.2 --- Performance Evaluation --- p.62 / Chapter 5.3 --- Summary --- p.67 / Chapter 6 --- Conclusion and Future Work --- p.68 / Chapter 6.1 --- Conclusion --- p.68 / Chapter 6.2 --- Future Work --- p.70 / Bibliography --- p.73
2

Antenna positioning analysis and dual-frequency antenna design of high frequency ratio for advanced electronic code responding labels.

Leong, Kin S. January 2008 (has links)
The research background of this thesis is Radio Frequency Identification (RFID), where an object can be identified remotely using electromagnetic waves. The focus of this thesis is on the in-depth investigation of two major problems in the RFID deployment in supply chain applications, namely the reader collision problem in dense reader environments and the tag performance problem in hostile environments. To resolve the reader collision problem, the first part of this thesis offers a comprehensive path loss model for the analysis of the positioning of RFID reader antennas. Simulation software was developed to predict the signal strength at a certain distance from a reader antenna in a dense reader environment. This simulation software was also utilised to publish insights and research results in four major areas, which are: (i) Investigation on the sources of error in RFID simulation, to provide sensible and meaningful simulation results before actual deployment of RFID readers. (ii) The development of the idea of reader synchronisation, mainly to address the strict regulations imposed on the deployment of RFID readers in Europe. (iii) The determination of the threshold value for second carrier sensing in RFID, to enable the proper enforcement of second carrier sensing to avoid tag confusion in dense reader environments. (iv) The examination of Specific Absorption Rate (SAR) to ensure human safety in a dense RFID reader environment. The second part of this thesis addresses the RFID tag performance problem in hostile environments. The focus is on the development of HF and UHF tags, from the initial tag antenna design, tag antenna simulation, tag antenna prototyping and measurement, to the manufacturing of fully functional RFID tags at laboratory standards by combining RFID chips on to tag antennas. Though there are existing commercial grade HF and UHF RFID tags, they are mostly aimed at pallet level applications and are not suitable for deployment in hostile environments. The study cases presented in this thesis are mostly industrially driven, where there is a need to design specialty HF and UHF tag antennas. With a strong foundation in the development of HF and UHF RFID tags for various industrially driven applications, the research then concentrates on the development of a novel dual-frequency RFID antenna, which operates in both the HF and UHF regions. This dual-frequency RFID tag antenna embraces the benefits of both the HF and UHF tag antenna, which enable it to have a good read range while operating in environments that pose difficulties for RFID technology, for example applications in which ionised liquid is present, such as in cases of wine or bottled drinks. Several methodologies were used to develop a dual-frequency antenna, including the merging of HF and UHF antennas, and having a UHF resonance point on a typical HF antenna. With the successful development of an original dual-frequency antenna, the research was then expanded to miniaturise this dual-frequency antenna. The benefits of RFID deployment in supply chains are undoubtedly massive, though there are still issues and challenges to be resolved before a world-wide adoption is possible. This thesis contributes in recommending various reader antenna positioning and deployment techniques, and also contributes in developing HF tag antennas and UHF tag antennas for hostile environments, and a novel dual-frequency tag antenna to progress towards the aim of ubiquitous object identification. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1330885 / Thesis (Ph.D.) - University of Adelaide, School of Electrical and Electronic Engineering, 2008
3

Radio frequency identification (RFID) at SMG Manufacturing, Inc.

Gay, Steven M. January 2004 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2004. / Includes bibliographical references.
4

High-performance RFID systems.

Jamali, Behnam January 2006 (has links)
Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / In this thesis, I present and analyze two of the most fundamental constraints of Radio Frequency Identification Systems (RFID), power rectification and signaling. These two issues play an important role in the continuing development of RFID systems. A passive RFID tag draws power from the RF field created by an RFID reader and uses it to energize its circuitry. It does this by rectification of the reader's radiated RF field using rectifying circuitry. The power then available to the tag is dependent upon both the available field strength and the efficiency of the rectification process. One option for increasing the operating range of an RFID system without increasing the reader's field strength is to increase the efficiency of the tag's rectification structure. A major component of any rectification circuit is a diode type device and so, the first part of the thesis focuses on the design and implementation of a novel high efficiency Schottky Barrier Diode (SBD) on a standard CMOS process. The forward voltage drop of the SBD diode was investigated and analytic equations formulated considering the Schottky barrier drift region resistance and the contributions from the p⁺ guard-grid. A design procedure to minimize the drift region resistance for any blocking voltage was derived. The fundamental trade-off between the forward voltage and leakage current in the novel SBD concept was determined. Based on the critical review of the Schottky diodes fabricated in the first part, new structures of novel SBD were designed to address most of the open issues related to its reverse break-down voltage and series resistance. Detailed analysis of the important design parameters of the novel Schottky barrier diode were performed using HSPICE with the parameter set used in the calibration process. The novel structure was also compared to an alternative fabrication approach, specifically, a NMOS and PMOS gate-cross-connected bridge. The comparison shows that the novel structure provides a 10% higher figure of merit for power rectification. In the later part of the thesis, an analysis of circuit advantages enabled by the novel SBD is given. The circuit simulation showed that by utilizing the novel SBD the operating frequency of the circuit can be increased to the UHF region while maintaining approximately the same power efficiency as that achievable when using a discrete Schottky diode. This leads to the possibility of dramatic improvements in size, weight and cost of the RFID transponder circuits. Signaling also plays an important role in the development of RFID systems. The choice of signaling methods and protocols determines not only the spectrum bandwidth usage, but also the data throughput. Also with constantly changing standards and regulations, it is important to be able to characterize and optimize these issues. Therefore the second part of this dissertation presents the design, implementation and evaluation of a novel RFID data logging reader architecture based on software radio concepts. The system is designed to overcome the many challenges and exploit the advantages of performing real-time signal processing and data logging in an RFID environment. The proposed concept has a unique multi-band RFID tag reader platform and has been designed to read tags conforming to the Electronic Product Code (EPC ) specifications in both the HF and UHF frequency bands. The hardware architecture consists of a general purpose analogue front end up/down-converter for each band, followed by a software radio based architecture allowing easy adaptation to new frequencies and protocols if required. The last chapter presents the results of investigations conducted to determine the ability of the proposed reader architecture to communicate with tags in typical channel noise and environmental conditions present in an RFID operational environment. Studies of the effects of reader interference in multi-reader environments and the development of an anti-collision protocol signaling to address and mitigate those effects are also presented. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1222149 / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2006
5

High-performance RFID systems.

Jamali, Behnam January 2006 (has links)
Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / In this thesis, I present and analyze two of the most fundamental constraints of Radio Frequency Identification Systems (RFID), power rectification and signaling. These two issues play an important role in the continuing development of RFID systems. A passive RFID tag draws power from the RF field created by an RFID reader and uses it to energize its circuitry. It does this by rectification of the reader's radiated RF field using rectifying circuitry. The power then available to the tag is dependent upon both the available field strength and the efficiency of the rectification process. One option for increasing the operating range of an RFID system without increasing the reader's field strength is to increase the efficiency of the tag's rectification structure. A major component of any rectification circuit is a diode type device and so, the first part of the thesis focuses on the design and implementation of a novel high efficiency Schottky Barrier Diode (SBD) on a standard CMOS process. The forward voltage drop of the SBD diode was investigated and analytic equations formulated considering the Schottky barrier drift region resistance and the contributions from the p⁺ guard-grid. A design procedure to minimize the drift region resistance for any blocking voltage was derived. The fundamental trade-off between the forward voltage and leakage current in the novel SBD concept was determined. Based on the critical review of the Schottky diodes fabricated in the first part, new structures of novel SBD were designed to address most of the open issues related to its reverse break-down voltage and series resistance. Detailed analysis of the important design parameters of the novel Schottky barrier diode were performed using HSPICE with the parameter set used in the calibration process. The novel structure was also compared to an alternative fabrication approach, specifically, a NMOS and PMOS gate-cross-connected bridge. The comparison shows that the novel structure provides a 10% higher figure of merit for power rectification. In the later part of the thesis, an analysis of circuit advantages enabled by the novel SBD is given. The circuit simulation showed that by utilizing the novel SBD the operating frequency of the circuit can be increased to the UHF region while maintaining approximately the same power efficiency as that achievable when using a discrete Schottky diode. This leads to the possibility of dramatic improvements in size, weight and cost of the RFID transponder circuits. Signaling also plays an important role in the development of RFID systems. The choice of signaling methods and protocols determines not only the spectrum bandwidth usage, but also the data throughput. Also with constantly changing standards and regulations, it is important to be able to characterize and optimize these issues. Therefore the second part of this dissertation presents the design, implementation and evaluation of a novel RFID data logging reader architecture based on software radio concepts. The system is designed to overcome the many challenges and exploit the advantages of performing real-time signal processing and data logging in an RFID environment. The proposed concept has a unique multi-band RFID tag reader platform and has been designed to read tags conforming to the Electronic Product Code (EPC ) specifications in both the HF and UHF frequency bands. The hardware architecture consists of a general purpose analogue front end up/down-converter for each band, followed by a software radio based architecture allowing easy adaptation to new frequencies and protocols if required. The last chapter presents the results of investigations conducted to determine the ability of the proposed reader architecture to communicate with tags in typical channel noise and environmental conditions present in an RFID operational environment. Studies of the effects of reader interference in multi-reader environments and the development of an anti-collision protocol signaling to address and mitigate those effects are also presented. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1222149 / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2006
6

Antenna positioning analysis and dual-frequency antenna design of high frequency ratio for advanced electronic code responding labels

Leong, Kin Seong. January 2008 (has links)
Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2008. / "January 2008" Includes bibliography (p. 333-342) Also available in print form.
7

Interactive visual optimization and analysis for RFID system performance /

Chung, Ka Kei. January 2009 (has links)
Includes bibliographical references (p. 45-47).
8

On the testing of the RFID security /

Xu, Dongming. January 2009 (has links)
Includes bibliographical references (p. 52-53).
9

RFID meets GWOT considering a new technology for a new kind of war

Kirby, Kevin Lee 06 1900 (has links)
The purpose of this thesis is to provide insight into the potential benefits that Radio Frequency Identification (RFID) technology may provide USSOCOM and other commands in the Global War on Terror. This thesis will explain the basic concept behind RFID, and cite some of the current day applications of today that are revolutionizing the civilian sector. More importantly, this thesis will introduce conceptual security applications that could benefit USSOCOM today, highlighting the possible successes and downfalls that these applications might include. / US Army (USA) author
10

Selektivt larmsystem

Cronholm, Simon, Zelejakovic, Faruk, Olofsson, Mikael January 2003 (has links)
No description available.

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