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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.
21

Anti-collision techniques for RFID systems.

January 2006 (has links)
Chiang Kong Wa. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 74-79). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Technology Overview --- p.4 / Chapter 2.1 --- Components of RFID Systems --- p.5 / Chapter 2.1.1 --- Tag --- p.6 / Chapter 2.1.2 --- Reader --- p.9 / Chapter 2.1.3 --- Software systems --- p.10 / Chapter 2.1.4 --- Communication infrastructure --- p.11 / Chapter 2.2 --- Frequency Regulations and Standards --- p.11 / Chapter 2.2.1 --- RFID frequency bands --- p.11 / Chapter 2.2.2 --- Standards --- p.12 / Chapter 2.3 --- Advantages and Limitations of RFID Technology --- p.14 / Chapter 2.4 --- Applications --- p.17 / Chapter 3 --- Background of Research --- p.20 / Chapter 3.1 --- Anti-collision methods for RFID systems --- p.22 / Chapter 3.1.1 --- Stochastic Anti-collision Protocols --- p.25 / Chapter 3.1.2 --- Deterministic Anti-collision Protocols --- p.27 / Chapter 4 --- Even-Odd Binary Tree Protocol --- p.30 / Chapter 4.1 --- Protocol Description --- p.31 / Chapter 4.2 --- Time Complexity Analysis --- p.34 / Chapter 4.3 --- Performance Evaluation --- p.37 / Chapter 4.4 --- Summary --- p.41 / Chapter 5 --- Prefix-Randomized Query-Tree Protocol --- p.44 / Chapter 5.1 --- Tag Identification - Known Tag Set Size --- p.45 / Chapter 5.1.1 --- Protocol Description --- p.45 / Chapter 5.1.2 --- Time Complexity Analysis --- p.47 / Chapter 5.1.3 --- Optimal Initial Prefix Length --- p.50 / Chapter 5.1.4 --- Optimal Number of Level-1 Nodes --- p.52 / Chapter 5.2 --- Tag Identification - Unknown Tag Set Size --- p.53 / Chapter 5.2.1 --- Initial Prefix Length Adaptation Algorithm --- p.54 / Chapter 5.2.2 --- Computing r*Δ(l) --- p.55 / Chapter 5.2.3 --- Optimal Choice of Step Size Δ --- p.56 / Chapter 5.3 --- Performance Evaluation --- p.59 / Chapter 5.4 --- Summary --- p.64 / Chapter 6 --- Conclusion and Future Work --- p.68 / Chapter 6.1 --- Conclusion --- p.68 / Chapter 6.2 --- Future Work --- p.70 / Bibliography --- p.74
22

Advanced power saving technologies for UHF band active RFID systems.

January 2006 (has links)
Wei Dacheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Abstracts in English and Chinese. / Table of Contents --- p.VIII / List of Tables --- p.XI / List of Figures --- p.XII / List of Abbreviations --- p.XV / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Introduction to RFID system --- p.1 / Chapter 1.2 --- Why we choose Active RFID system --- p.4 / Chapter 1.3 --- Objective of the research --- p.6 / Chapter 1.3.1 --- Requirement analysis --- p.7 / Chapter 1.3.2 --- Selection of RFID system and standard --- p.8 / Chapter 1.4 --- Original contribution of this dissertation --- p.9 / Chapter 1.5 --- Organization of the dissertation --- p.9 / Reference --- p.10 / Chapter Chapter 2 --- Implementation of An Active RFID System / Chapter 2.1 --- RFID System hardware design and related protocol --- p.1 / Chapter 2.2 --- Introduction to ISO 18000-7 --- p.7 / Chapter 2.3 --- Microcontroller specification --- p.12 / Chapter 2.4 --- RF model specifications --- p.14 / Chapter 2.5 --- Communication between a PC and a Reader --- p.15 / Chapter 2.6 --- Programming --- p.16 / Chapter 2.6.1 --- Procedure sequences of Reader and Tag --- p.17 / Chapter 2.6.2 --- Sequence of data transmission and reception --- p.24 / Chapter 2.6.3 --- CRC implementation --- p.28 / Chapter 2.7 --- Testing result --- p.31 / Reference --- p.35 / Chapter Chapter 3 --- Novel Power Saving Methods for an Active RFID System / Chapter 3.1 --- Some drawbacks of the existing Active RFID protocol --- p.1 / Chapter 3.1.1 --- Power consumption problem --- p.1 / Chapter 3.1.2 --- Multi-Reader problem --- p.9 / Chapter 3.2 --- Solutions of the Multi-Reader problem and power saving problem --- p.10 / Chapter 3.2.1 --- A solution to the power saving problem --- p.11 / Chapter 3.2.2 --- A solution to the Multi-Reader problem --- p.16 / Reference --- p.21 / Chapter Chapter 4 --- A Probe-fed Compact Half-wave Length Dipole Antenna for Active RFID System / Chapter 4.1 --- Requirement of an antenna for Active RFID system --- p.1 / Chapter 4.2 --- A probe-fed half-wave length dipole EE shape antenna for metallic object application --- p.2 / Chapter 4.3 --- Electromagnetic simulation results --- p.5 / Chapter 4.4 --- Operating principle analysis --- p.9 / Chapter 4.5 --- Using V shape structure to increase the bandwidth --- p.19 / Chapter 4.6 --- Prototyping and measurement results --- p.22 / Chapter 4.7 --- Conclusion --- p.28 / Reference --- p.29 / Chapter Chapter 5 --- Conclusion
23

A theory of RFID anti-collision mechanisms. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Due to the recent advances in semiconductor technology, the Radio Frequency Identification (RFID) technology is approaching the critical point for inventory application in global supply chain logistics. Its unique advantage to identify multiple tags simultaneously can remove large amount of labor-intensive scanning for inventory control and checkout process. To realize multiple-tag-identification, the tag collision problem, which is due to the signal collision of simultaneous transmission by multiple tags, needs to be solved. / Over the years, many different RFID systems and anti-collision algorithms were proposed, but a uniform theory which fully analyzes the anti-collision system is still lacking. Most of the previous work treated the RFID system as a special kind of Random Access (RA) system and designed anti-collision algorithms to maximize the temporary throughput. In this thesis, we provide a theoretical framework for the RFID anti-collision system. We differentiate the RFID system with the RA system and propose a general model for all types of the RFID systems. We also provide a general method for algorithm optimization in different RFID systems. As special examples, we analyze some popular RFID systems and derive the optimal algorithms under the system constraints. These optimal results are verified by computer simulation. / Zhu, lei. / Adviser: Tak-shing Peter Yum. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 152-156). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
24

RFIDs användning i produktionsprocesser : en studie bland operatörer på Lear Corporation

Andersson, Jessica, Larsson, Stina, Jendesand, Gunilla January 2005 (has links)
No description available.
25

Next Generation RFID Randomization Protocol

LaValley, Jason 06 December 2011 (has links)
Radio Frequency IDentification (RFID) is a wireless communications technology which allows companies to secure their assets and increase the portability of information. This research was motivated by the increased commercial use of RFID technology. Existing security protocols with high levels of security have high computation requirements, and less intensive protocols can allow a tag to be tracked. The techniques proposed in this thesis result in the increase of ciphertexts available without a significant increase in processing power or storage requirements. The addition of random inputs to the generation of ciphertexts will increase the number of possible results without requiring a more advanced encryption algorithm or an increased number of stored encryption keys. Four methods of altering the plaintext/ciphertext pair (random block, set pattern, random pattern, and indexed placement) are analyzed to determine the effectiveness of each method. The number of ciphertexts generated, generation time, and generation errors were recorded to determine which of the four proposed methods would be the most beneficial in a RFID system. The comparison of these method characteristics determined that the set pattern placement method provided the best solution. The thesis also discusses how RFID transmissions appear to attackers and explains how the random inputs reduce effectiveness of current system attacks. In addition to improving the anonymity of RFID tag transmissions, the concept of authenticating random inputs is also introduced in this thesis. These methods help prevent an adversary from easily associating a tag with its transmissions, thus increasing the security of the RFID system.
26

Next Generation RFID Randomization Protocol

LaValley, Jason 06 December 2011 (has links)
Radio Frequency IDentification (RFID) is a wireless communications technology which allows companies to secure their assets and increase the portability of information. This research was motivated by the increased commercial use of RFID technology. Existing security protocols with high levels of security have high computation requirements, and less intensive protocols can allow a tag to be tracked. The techniques proposed in this thesis result in the increase of ciphertexts available without a significant increase in processing power or storage requirements. The addition of random inputs to the generation of ciphertexts will increase the number of possible results without requiring a more advanced encryption algorithm or an increased number of stored encryption keys. Four methods of altering the plaintext/ciphertext pair (random block, set pattern, random pattern, and indexed placement) are analyzed to determine the effectiveness of each method. The number of ciphertexts generated, generation time, and generation errors were recorded to determine which of the four proposed methods would be the most beneficial in a RFID system. The comparison of these method characteristics determined that the set pattern placement method provided the best solution. The thesis also discusses how RFID transmissions appear to attackers and explains how the random inputs reduce effectiveness of current system attacks. In addition to improving the anonymity of RFID tag transmissions, the concept of authenticating random inputs is also introduced in this thesis. These methods help prevent an adversary from easily associating a tag with its transmissions, thus increasing the security of the RFID system.
27

RFIDs användning i produktionsprocesser : en studie bland operatörer på Lear Corporation

Andersson, Jessica, Larsson, Stina, Jendesand, Gunilla January 2005 (has links)
No description available.
28

Design of Antennas for Radio Frequency Identification and Analysis of Power Coupling Effects

Wang, Pai-Chieh 25 July 2005 (has links)
In this paper, we propose tag antennas and reader antennas, which are suitable for radio frequency identification system. Antennas operating in the ISM and the UHF bands are designed. The antenna dimensions are minimized by employing the meander-line technology. Adopting the concepts of Yagi-Uda antennas, We use parasites to increase the antenna gain and to create an end-fire radiation pattern. The fact that the design comes without a ground plane can achieve cost down of the antenna. Higher antenna gains allow a greater effective read-zone distance. Also, the directional radiation pattern eliminates the degradation of performance due to multi-path loss. The design of tag antennas shows good performances in terms of both cost and antenna characteristics for radio frequency identification systems. The reader antennas are designed. Etching a slit in a square patch can achieve the requirement of circular polarization. It can effectively reduce the polarization mismatch when the tags are point to different orientation. Therefore the reliability of system operation will be improved. The antenna performance is measured by the experiments. Moreover, it will be compared with the simulation. In the latter part of paper, the simulation of the power coupling will be carried out. According to the result of power coupling simulation, we analyze and discuss which factor will affect the reliability of the identification. Identification failure will be effectively avoided and a robust identification system can be built if the analyses are properly employed.
29

Aerial remote radio frequency identification system for small vessel monitoring

Appler, Jason A. Finney, Sean M. McMellon, Michael A. January 2009 (has links) (PDF)
"Submitted in partial fulfillment of the requirements for the degree of Master of Business Administration from the Naval Postgraduate School, December 2009." / Advisor(s): Dew, Nicholas ; Hudgens, Bryan. "December 2009." "MBA Professional report"--Cover. Description based on title screen as viewed on January 26, 2010. Author(s) subject terms: RFID, Radio Frequency Identification, airborne, vessel monitoring. Includes bibliographical references (p. 103-110). Also available in print.
30

Object localization using passive RFID tags

Jayaraman, Ramprabhu, January 2009 (has links)
Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Electrical and Computer Engineering." Includes bibliographical references (p. 69-70).

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