• Journal of Internet Computing and Services
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• v.14 no.4
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• pp.25-33
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• 2013

The procedure of the arbitration which is the tag collision is essential because the multiple tags response simultaneously in the same frequency to the request of the Reader. This procedure is known as Anti-collision and it is a key technology in the RFID system. In this paper, we propose the 4-Bit Pattern Slot Allocation(4-BPSA) algorithm for the high-speed identification of the multiple tags. The proposed algorithm is based on the tree algorithm using the time slot and identify the tag quickly and efficiently through accurate prediction using the a slot as a 4-bit pattern according to the slot allocation scheme. Through mathematical performance analysis, We proved that the 4-BPSA is an O(n) algorithm by analyzing the worst-case time complexity and the performance of the 4-BPSA is improved compared to existing algorithms. In addition, we verified that the 4-BPSA is performed the average 0.7 times the query per the Tag through MATLAB simulation experiments with performance evaluation of the algorithm and the 4-BPSA ensure stable performance regardless of the number of the tags.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.11A
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• pp.1130-1137
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• 2006

One of the important performance issues in large-scale RFID systems is to resolve collisions among responses from RFID tags. Considering two do facto anti-collision solutions, namely the binary-tree splitting algorithm and the Slotted-Aloha algorithm, we propose to use multi-packet reception (MPR) capability to enhance the RFID tag reading rate (i.e., throughput). MPR allows an RFID reader to receive multiple reponses transmitted by tags at the same time. We analyze the effect of MPR capability in the above anti-collision algorithms, which is also validated by simulation. The analysis and simulation results show that RFID reader antenna design and signal separation techniques play an important role in improving RFID system performance with MPR capability.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.434-437
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• 2006

Today, Hospital Information System that integrates ubiquitous technologies are introduced in limited basis due to problems like standardization and limits on medical use, where responsibilities lie, legal safeguard on transmission, invasion of privacy etc. Particularly, problems like absence of tag design suitable for medical environment, compatibility issue with previous medical information system. In order to solve such problems, we have designed medical tags for the first time that are consistent with future ubiquitous environment by deciding on medically suitable field with 96bit tag offered by EFC as its base. Second, improving on previous multi-tag recognizing crash prevention algorithm, we have designed a priority anti-collision algorithm that reflects priorities on the needs in medical environment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.712-714
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• 2016

The PS algorithm divides the tags within the identification range of reader into smaller groups by increasing the transmission power incrementally and identifies them. In 13.56MHz RFID system of Auto-ID center, STAC protocol is defined as an anti-collision algorithm for multiple tag reading. In this paper, we propose a STAC/PS algorithm that the PS algorithm is applied in the STAC protocol. The simulation results show that the STAC/PS algorithm can achieve faster tag identification speed compared with STAC protocol due to the low collision rate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.55-58
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• 2008

RFID(Radio frequency IDentification) leader is collision of data, when recognizing the multiple tag the inside area. This collision became the cause which delays the tag recognition time of the leader. The protocol which prevents the delay of tag recognition time of the leader the place where representative it uses QT(Query Tree) algorithms, it uses a collision bit position from this paper and are improved QT-MTC(Query Tree with Multi-Tag Cognition) algorithms which it proposes. This algorithm stored the bit position which bit possibility and the collision where the collision happens occurs in the stack and goes round a tree the number of time which, it reduced could be identified two tags simultaneously in order, it was planned. A result of performance analysis, It compared in QT protocols and the this algorithm against the tag bit which is continued a tush efficiency improvement effect was visible.

• 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.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.5
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• pp.547-554
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• 2010

RFID is core technology to lead ubiquitous computing, and attract the notice of the world. It also improves social transparency, creates employment, and invigorates the allied industries. However, The technical characteristic with RFID has some problems with security and privacy. The commercialization of RFID is delayed due to these problems. This paper introduces the technical method to find solutions about an invasion of privacy to be due to introduce RFID system. First, this method applies Hash-Chain proposed by M. Ohkubo and some other researchers. The more tags increase, the more it demands lots of computation time. We divide SPs equally to solve these problems. And then, We'll suggest solutions to shorten the identification time of tag by implementing SPs with multi nodes of Grid environment at the same time. This makes it possible to keep the privacy protection of RFID tag, and process RFID tag in real time at the same time.

• The KIPS Transactions:PartA
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• v.16A no.4
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• pp.289-298
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• 2009

Generally, RFID systems are composed of one reader and several passive tags, and share the single wireless channel. For this reason, collisions occurwhen more than two tags simultaneously respond to the reader's inquiry. To achieve this problem, many papers, such as QT[8], HCT[10], BSCTTA[2], and QT-BCS[9], have been proposed. In this paper, we propose the tree-based anti-collision algorithm using a bit change sensing unit (TABCS) based on BSCTTA algorithm. The proposed algorithm can identify bits returned from tags through bit change sensing unit, even if multi collisions occur. So, it rapidly generates the unique prefix to indentify each tag, and reduce the total of bits. As the result, the cost of identifying all tag IDs is relatively reduced as compared with existing algorithms. It is verified through simulations that the proposed algorithm surpass other existing algorithms.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.6
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• pp.999-1005
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• 2008

RFID(Radio Frequency IDintification) leader is collision of data, when recognizing the multiple tag the inside area. This collision became the cause which delays the tag recognition time of the leader. The protocol which prevents the delay of tag recognition time of the leader the place where representative it uses QT(Query Tree) algorithms, it uses a collision bit position from this paper and are improved QT-MTC(Query Tree with Multi-Tag Cognition) algorithms which it proposes. This algorithm stored the bit position which bit possibility and the collision where the collision happens occurs in the stack and goes round a tree the number of time which, it reduced could be identified two tags simultaneously in order, it was planned. A result of performance analysis, It compared in QT protocols and the this algorithm against the tag bit which is continued a high efficiency improvement effect was visible.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06d
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• pp.172-176
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• 2007

유통분야에서 물품관리를 위해 사용되었던 바코드를 대체할 차세대 인식기술로 꼽히는 RFID 기술은 IT기술의 주요 시장으로 부상하면서 다양한 연구가 이루어지고 있는 분야이다. 유통 및 물류분야에서는 다량의 물품을 실시간으로 식별해야 하는 경우가 필요한데 이를 위해 여러 개의 리더가 동시에 사용 된다. RFID 시스템을 구축하는데 있어서 다중 리더 운영 기법은 전체 RFID 시스템의 성능을 좌우한다. EPCglobal에서 제안 된 Gen2 프로토콜은 900MHz 대역의 단일 통합 표준으로서 ISO/IEC 18000-6 C타입으로 채택되었다. 하지만 Gen2 프로토콜에서 다중 리더 운영 정책에 대해서 Session 기능을 간단히 내놓았을 뿐 자세한 소프트웨어 응용법을 제시하지 않았으며, 이에 관한 미들웨어 연구도 이루어지고 있지 않다. 본 논문에서는 현재 Gen2 프로토콜에서의 태그 인식 기술과 EPCglobal에서 제안하는 RFID 프로토콜, Sesssion 개념을 소개하고 Gen2 프로토콜을 이용하는 RFID 시스템에 다중 리더 관리 모듈을 설계를 통해 다중 리더를 운영하는 기법을 제안한다.