• Title/Summary/Keyword: RFID Reader Collision

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Fast Anti-collision Algorithm for Improving Tag Identification Speed in EPC Class 1 RFID System (EPC Class 1 RFID 시스템에서 태그 인식 속도 향상을 위한 고속 태그 충돌 방지 알고리즘)

  • Lee, Choong-Hee;Kim, Jae-Hyun
    • 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.

Adaptive Group Separation Anti-Collision Algorithm for Efficient RFID System (효율적인 RFID 시스템을 위한 Adaptive Group Separation 충돌방지 알고리듬)

  • Lee, Hyun-Soo;Lee, Suk-Hui;Bang, Sung-Il
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.299-300
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    • 2008
  • In this paper, we propose Adaptive Group Separation(AGS) algorithm for efficient RFID system. AGS algorithm determines the optimized initial prefix size m, and divides the group of ��$2^m$. A reader requests the group and searches the tag ID. If a tag collision occurred, reader adds a one bit, '0' or '1' at first bit of collision point. As a result, we observe that transmitted data bits and the recognition time are decreased.

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Improvement of Tag Collection Performance for Active RFID Systems (능동형 RFID 시스템을 위한 태그 수집 성능 개선)

  • Yoon, Won-Ju;Chung, Sang-Hwa;Moon, Young-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.7B
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    • pp.518-527
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    • 2008
  • Tag collection is one of the major functions in Radio Frequency Identification (RFID) systems. IS0/IEC 18000-7 defines the tag collection algorithm using the anti-collision algorithm, based on the framed slotted ALOHA for active RFID systems. However, it has inefficiency problems that reduce tag collection performance by deciding non-optimum slot size or using point-to-point commands to put collected tags to sleep. In this paper, we propose two mechanisms to overcome the inefficiency problems and improve tag collection performance: 1) a new slot size decision mechanism to allow the reader to choose the optimum slot size flexibly and 2) a broadcast-based sleep mechanism to put collected tags to sleep effectively. We also implemented an active RFID system, composed of an active RFID reader and multiple tags, and the reader is designed to maximize tag collection performance when the proposed mechanisms are applied. In experiments, we evaluated the tag collection performance using one reader and 50 tags in the real-world environment. The experimental results show that when two mechanisms are applied and the initial number of slots is chosen appropriately, the performance of the proposed tag collection algorithm is greatly enhanced, compared with that of the standard.

A Slot Allocated Blocking Anti-Collision Algorithm for RFID Tag Identification

  • Qing, Yang;Jiancheng, Li;Hongyi, Wang;Xianghua, Zeng;Liming, Zheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.6
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    • pp.2160-2179
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    • 2015
  • In many Radio Frequency Identification (RFID) applications, the reader recognizes the tags within its scope repeatedly. For these applications, some algorithms such as the adaptive query splitting algorithm (AQS) and the novel semi-blocking AQS (SBA) were proposed. In these algorithms, a staying tag retransmits its ID to the reader to be identified, even though the ID of the tag is stored in the reader's memory. When the length of tag ID is long, the reader consumes a long time to identify the staying tags. To overcome this deficiency, we propose a slot allocated blocking anti-collision algorithm (SABA). In SABA, the reader assigns a unique slot to each tag in its range by using a slot allocation mechanism. Based on the allocated slot, each staying tag only replies a short data to the reader in the identification process. As a result, the amount of data transmitted by the staying tags is reduced greatly and the identification rate of the reader is improved effectively. The identification rate and the data amount transmitted by tags of SABA are analyzed theoretically and verified by various simulations. The simulation and analysis results show that the performance of SABA is superior to the existing algorithms significantly.

Anti-Collision Algorithm for Improvement of Multiple Tag Identification in RFID System (RFID 시스템에서 다중 태그 인식 개선을 위한 충돌방지 알고리즘)

  • Kim, Yong-Hwan;Ryoo, Myung-Chun;Park, Joon-Ho
    • Journal of Information Technology Services
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    • v.12 no.3
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    • pp.331-343
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    • 2013
  • In RFID systems, the anti-collision algorithm is being improved to recognize Tag's ID within recognition area of the reader quickly and efficiently. This paper focuses on Tag collision. Many studies have been carried out to resolve Tag collision. This paper proposes a new N-ary Query Tree Algorithm to resolve more than Tag collision simultaneously, according to the value of m(2 ~ 6). This algorithm can identify more tags than existing methods by treating a maximum 6 bit collision, regardless of the continuation/non-continuation Tag's ID patterns. So, it extracts maximumly different $2^6$ bit patterns per single prefix in recognition process. The performance of N-ary Query Tree Algorithm is evaluated by theoretical analysis and simulation program.

Improved variable bits M-ary QT conflict resolution algorithm for discrete m-bits recognition in RFID system (RFID 시스템에서 불연속 m-bits 인식을 위한 개선된 가변비트 M-ary QT 충돌해소 알고리즘)

  • Kim, Kwan-woong;Kim, Byun-gon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.10
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    • pp.1887-1894
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    • 2016
  • In the RFID system, the reader transmits a query message to tags in order to identify a unique ID of tags within its detection range. The procedures for arbitrating a collision is essential because the multiple tags can response simultaneously in the same to the query of the Reader. This procedure is known as conflict resolution algorithm and it is a key technology in the RFID system. In this paper, we proposed a variable bits M-ary QT algorithm based on Manchester coding techniques. The proposed algorithm use the location information of the collision bits in the reader and tags. The proposed algorithm can reduce the number of the query-response cycle because it is capable of recognizing discontinuous bits and a variable number of bits. From computer simulation, the proposed method give better performance than the conventional M-ary QT techniques in terms of response, recognition efficiency, communication overhead.

A Study on Performance Enhancement of RFID Anti-Collision Protocols (RFID 충돌방지 프로토콜의 성능 개선에 관한 연구)

  • Kim, Young-Beom
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.4
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    • pp.281-285
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    • 2011
  • One of the key issues in implementing RFID systems is to design anti-collision protocols for identifying all the tags in the interrogation zone of a RFID reader with the minimum identification delay. In this paper, Furthermore, in designing such protocols, the limited resources in tags and readers in terms of memory and computing capability should be fully taken into consideration. we first investigate two typical RFID anti-collision algorithms, namely RFID Gen2 Q algorithm (accepted as the worldwide standard in industrial domain) and FAFQ algorithm including their drawbacks and propose a new RFID anti-collision algorithm, which can improve the performance of RFID systems in terms of tag identification time considerably. Further, we compared performance of the proposed algorithm with Q algorithm and FAFQ algorithm through computer simulation.

Adaptive RFID anti-collision scheme using collision information and m-bit identification (충돌 정보와 m-bit인식을 이용한 적응형 RFID 충돌 방지 기법)

  • Lee, Je-Yul;Shin, Jongmin;Yang, Dongmin
    • Journal of Internet Computing and Services
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    • v.14 no.5
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    • pp.1-10
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    • 2013
  • RFID(Radio Frequency Identification) system is non-contact identification technology. A basic RFID system consists of a reader, and a set of tags. RFID tags can be divided into active and passive tags. Active tags with power source allows their own operation execution and passive tags are small and low-cost. So passive tags are more suitable for distribution industry than active tags. A reader processes the information receiving from tags. RFID system achieves a fast identification of multiple tags using radio frequency. RFID systems has been applied into a variety of fields such as distribution, logistics, transportation, inventory management, access control, finance and etc. To encourage the introduction of RFID systems, several problems (price, size, power consumption, security) should be resolved. In this paper, we proposed an algorithm to significantly alleviate the collision problem caused by simultaneous responses of multiple tags. In the RFID systems, in anti-collision schemes, there are three methods: probabilistic, deterministic, and hybrid. In this paper, we introduce ALOHA-based protocol as a probabilistic method, and Tree-based protocol as a deterministic one. In Aloha-based protocols, time is divided into multiple slots. Tags randomly select their own IDs and transmit it. But Aloha-based protocol cannot guarantee that all tags are identified because they are probabilistic methods. In contrast, Tree-based protocols guarantee that a reader identifies all tags within the transmission range of the reader. In Tree-based protocols, a reader sends a query, and tags respond it with their own IDs. When a reader sends a query and two or more tags respond, a collision occurs. Then the reader makes and sends a new query. Frequent collisions make the identification performance degrade. Therefore, to identify tags quickly, it is necessary to reduce collisions efficiently. Each RFID tag has an ID of 96bit EPC(Electronic Product Code). The tags in a company or manufacturer have similar tag IDs with the same prefix. Unnecessary collisions occur while identifying multiple tags using Query Tree protocol. It results in growth of query-responses and idle time, which the identification time significantly increases. To solve this problem, Collision Tree protocol and M-ary Query Tree protocol have been proposed. However, in Collision Tree protocol and Query Tree protocol, only one bit is identified during one query-response. And, when similar tag IDs exist, M-ary Query Tree Protocol generates unnecessary query-responses. In this paper, we propose Adaptive M-ary Query Tree protocol that improves the identification performance using m-bit recognition, collision information of tag IDs, and prediction technique. We compare our proposed scheme with other Tree-based protocols under the same conditions. We show that our proposed scheme outperforms others in terms of identification time and identification efficiency.

A study on improvement method about the collision problem of RFID reader (RFID 리더 상의 충돌 문제 개선 방안에 관한 연구)

  • 김봉재;윤미연;박종일;신용태;나정정
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10c
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    • pp.712-714
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    • 2004
  • 최근 유비쿼터스 주요 이슈로 부각되는 Atuo ID나 유비쿼터스 ID(Ubiquitous ID)은 RFID(Radio Frefuency Identification) 태그(Tag)를 사용한 차세대 ID 체계이다. 이들 식별 체계는 해당 물품에 부착된 태그 정보를 RFID 리더(Reader)가 판독하여 이를 바탕으로 식별 작업을 수행함으로써 짧은 시간에 많은 물류 식별 처리가 가능할 수 있는 메커니즘을 가지고 있다. 하지만 리더가 수많은 태그 정보를 한꺼번에 모두 받아드림으로써 발생하는 여러 가지 오류가 발생할 수 있는데, 이를 충돌 문제(collision problem)이라 한다 본 논문은 충돌 문제들의 형태를 분석하고, 이를 개선할 수 있는 방안에 대해 모색, 제안하고자 한다.

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