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Optimal Time Structure for Tag Cognizance Scheme based on Framed and Slotted ALOHA in RFID Networks  

Choi, Cheon-Won (Dankook University)
Publication Information
Journal of the Institute of Electronics Engineers of Korea TC / v.47, no.9, 2010 , pp. 29-36 More about this Journal
Abstract
Consider an RFID network configured as a star such that a single reader is surrounded by a crowd of tags. In the RFID network, prior to attaining the information stored at a tag, the reader must cognize the tags while arbitrating a collision among tags' responses. For this purpose, we present a tag cognizance scheme based on framed and slotted ALOHA, which statically provides a number of slots in each frame for the tags to respond. For the evaluation of the cognizance performance, we choose the cognizance completion probability and the expected cognizance completion time as key performance measures. Then, we present a method to numerically calculate the performance measures. Especially, for small numbers of tags, we derive them in a closed form. Next, we formulate a problem to find an optimal time structure which either maximizes the cognizance completion probability under a constraint on the cognizance time or minimizes the expected cognizance completion time. By solving the problem, we finally obtain an optimal number of slots per frame for the tags to respond. From numerical results, we confirm that there exist a finite optimal number of slots for the tags to respond. Also, we observe that the optimal number of slots maximizing the cognizance completion probability tends to approach to the optimal number of slots minimizing the expected cognizance completion time as the constraint on the cognizance time becomes loose.
Keywords
RFID network; tag cognizance; framed and slotted ALOHA; cognizance completion; optimal structure;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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1 B. Glover and H. Bhatt, RFID Essentials. O'Reilly, 2006.
2 K. Finkenzeller, RFID Handbook - Fundamentals and Applications in Contactless Smart Cards and Identification. John Wiley & Sons, 2006.
3 H. Vogt, "Efficient Object Identification with Passive RFID Tags," Proceedings of International Conference on Pervasive Computing 2002, pp. 98-113, 2002.
4 J. Cha and J. Kim, "ALOHA-type Anti-collision Algorithms Using Tag Estimation Method in RFID system," Journal of KICS, vol. 30, no. 9A, pp. 814-821, September 2005.   과학기술학회마을
5 J. Park, W. Shin, J. Ha, J. Jung, and C. Choi, "Estimation of the Number of Tags for Framed and Slotted ALOHA in RFID Networks," Proceedings of JCCI 2007, 2007.
6 J. Park, W. Shin, J. Ha, and C. Choi, "Bayes Action for Tag Cognizance in RFID Networks," Proceedings of IEICE/IEEK ITC-CSCC 2007, 2007.
7 J. Park, W. Shin, J. Ha, and C. Choi, "Decision of the Number of Slots for Framed Slotted ALOHA in RFID Networks: Bayesian Approach," Proceedings of IEEE APWCS 2007, 2007.
8 J. Park, J. Ha and C. Choi, "Bayesian Cognizance of RFID Tags," Journal of IEEK, vol. 46, no. 5, pp. 524-531, May 2009.   과학기술학회마을
9 W. Feller, An Introduction to Probability Theory and Its Applications. 2nd edition, John Wiley & Sons, 1968.