• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.253-259
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• 2008

RFID is a generic term for technologies which use RF waves to identify, track, or categorize any object. A radio frequency identification (RFID) reader recognizes objects through wireless communications with RFID tags. Tag collision arbitration for passive tags is a significant issue for fast tag identification due to communication over a shared wireless channel. One of the research areas in RFID system is a tag anti-collision protocol. In this paper, various anti-collision protocols are discussed. The pros and cons of different anti-collision protocols are compared with each other and their performance is analyzed and the better performance anti-collision protocol is suggested.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6B
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• pp.450-455
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• 2008

We analyze the tag identification procedure of conventional EPC Class 1 RFID system and propose the fast anti-collision algorithm for the performance improvement of the system. In the proposed algorithm, the reader uses information of tag collisions and reduces unnecessary procedures of the conventional algorithm. We evaluate the performance of the proposed anti-collision algorithm and the conventional algorithm using mathematical analysis and simulation. According to the results, the fast anti-collision algorithm shows greatly better performance than conventional algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.1B
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• pp.17-26
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• 2005

RFID(Radio Frequency IDentification) is a technology that automatically identifies objects attached with electronic tags by using radio wave. For the implementation of an RFID system, an anti-collision algorithm is required to identify several tags within the RFID reader's range. Few researches report the performance trade-off among anti-collision algorithms in terms of the communications traffic between the reader and tags, the identification speed, and so on. In this paper, we analyze both tree based memoryless algorithms and slot aloha based algorithms that comprise of almost every class of existing anti-collision algorithms. To compare the performance, we evaluated each class of anti-collision algorithms with respect to low-cost RFID system with 96-bit EPC(Electronic Product Code). The results show that the collision tracking tree algorithm outperforms current tree based and aloha based algorithms by at least 2 times to 50 times.

• ETRI Journal
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• v.30 no.5
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• pp.653-662
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• 2008

Arbitration of tag collision is a significant issue for fast tag identification in RFID systems. A good tag anti-collision algorithm can reduce collisions and increase the efficiency of tag identification. EPCglobal Generation-2 (Gen2) for passive RFID systems uses probabilistic slotted ALOHA with a Q algorithm, which is a kind of dynamic framed slotted ALOHA (DFSA), as the tag anti-collision algorithm. In this paper, we analyze the performance of the Q algorithm used in Gen2, and analyze the methods for estimating the number of slots and tags for DFSA. To increase the efficiency of tag identification, we propose new tag anti-collision algorithms, namely, Chebyshev's inequality, fixed adjustable framed Q, adaptive adjustable framed Q, and hybrid Q. The simulation results show that all the proposed algorithms outperform the conventional Q algorithm used in Gen2. Of all the proposed algorithms, AAFQ provides the best performance in terms of identification time and collision ratio and maximizes throughput and system efficiency. However, there is a tradeoff of complexity and performance between the CHI and AAFQ algorithms.

• Journal of information and communication convergence engineering
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• v.6 no.1
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• pp.24-28
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• 2008

In RFID System, when multiple tags respond simultaneously, a collision can occur. A method that solves this collision is referred to anti-collision algorithm. Among the existing anti-collision algorithms, static framed slot allocation algorithm is very simple. But when the number of tags is variable, its performance degrades because of the fixed frame size. This paper proposes an optimal frame size allocation scheme that determines the frame size. The proposed scheme is based on the number of collision slots at every frame. According to the simulation results, the tag identification time is faster that of SFSA.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.4
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• pp.61-67
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• 2011

In these days, RFID adoption in supply chain management system needs technically part of the performance improvement of RFID Anti-Collision technology. We contrived new scanning algorithm that improve RFID Anti Collision performance, also can be applied to existing RFID readers. In this paper, the proposed algorithm were applied to the actual logistics scene recognition performance much better than the existing practices are presented. For improve of RFID Anti Collision performance, our algorithm implemented in the middleware associated with RFID PDA readers, and actually mount the RFID inventory data from the experiment were accumulated. Through this experiment, the proposed algorithm was confirmed that helps to minimize unaware area of the existing RFID inventory system and significantly improves performance of RFID field solution.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.1 s.343
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• pp.41-48
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• 2006

An anti-collision algorithm is very important in the RFID system because it decides tag identification time and tag identification accuracy. We propose improved anti-collision algorithms using Bin slot in RFID system. In the proposed algorithms, if the reader memorizes the Bin slot information, it can reduce the repetition of unnecessary PingID command and the time to identify tags. If we also use ScrollA11ID command in the proposed algorithm, the reader knows the sequence of collided E bits. Using this sequence, the reader can reduce the repetition of PingID command and tag identification time. We analyze the performance of the proposed anti-collision algorithms and compare the performance of the proposed algorithms with that of the conventional algorithm. We also validate analytic results using simulation. According to the analysis, for the random tag n, comparing the proposed algorithms with the conventional algorithm, the performance of the proposed algorithms is about $130\%$ higher when the number of the tags is 200. And for the sequential tag ID, the performance of the conventional algorithm decreases. On the contrary, the performance of the proposed algerian using ScrollA11ID command is about $16\%$ higher than the case of using random tag ID.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.4
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• pp.1460-1478
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• 2020

This paper proposes a novel anti-collision protocol for large-scale RFID tags identification, named Bi-response Collision Tree Protocol (BCT). In BCT, two group of tags answer the reader's same query in two response-cycles respectively and independently according to the bi-response pattern. BCT improves the RFID tag identification performance significantly by decreasing the query cycles and the bits transmitted by the reader and tags during the identification. Computation and simulation results indicate that BCT improves the RFID tag identification performance effectively, e.g. the tag identification speed is improved more than 13.0%, 16.9%, and 22.9% compared to that of Collision Tree Protocol (CT), M-ary Collision Tree Protocol (MCT), and Dual Prefix Probe Scheme (DPPS) respectively when tags IDs are distributed uniformly.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.5
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• pp.2294-2309
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• 2020

In this article, a new Aloha-based tag identification protocol is presented to improve the reading efficiency of the EPC C1 Gen2-based UHF RFID system. Collision detection (CD) plays a vital role in tag identification process which determines the efficiency of anti-collision protocols since most Aloha-based protocols optimize the incoming frame length based on the collisions in current frame. Existing CD methods are ineffective in identifying collision, resulting in a degradation of identification performance. Our proposed algorithm adopts an enhanced CD (ECD) scheme based on the EPC C1 Gen2 standard to optimize identification performance. The ECD method can realize timely and effective CD by detecting the pulse width of the randomly sent by tags. According to the ECD, the reader detects the slot distribution and predicts tag cardinality in every collision slot. The tags involved in each collision slot are identified by independently assigned sub-frames. A large number of numerical results show that the proposed solution is superior to other existing anti-collision protocols in various performance evaluation metrics.

• Journal of information and communication convergence engineering
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• v.7 no.3
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• pp.292-296
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• 2009

The performance of anti-collision algorithm in RFID systems, which are based on FSA algorithm, may be affected by the frame size a query round. In this paper, an anti-collision algorithm with early cancellation of query round is proposed to enhance the performance of EPCglobal Class-1 Gen-2. The Q-algorithm calculates a Q value to determine the next frame size during a query round. In the proposed algorithm, if the new Q value is different from the previous one, the reader transmits a QueryAdjust command to cancel the current query round. The simulation results show that the proposed algorithm can have a stable performance irrespective of the C value of Q-algorithm and the number of tags.