• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.1
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• pp.165-182
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• 2014

An RFID systems employ efficient Anti-Collision Algorithms (ACAs) to enhance the performance in various applications. The EPC-Global G2 RFID system utilizes Frame Slotted Aloha (FSA) as its ACA. One of the common approaches used to maximize the system performance (tag identification efficiency) of FSA-based RFID systems involves finding the optimal value of the frame length relative to the contending population size of the RFID tags. Several analytical models for finding the optimal frame length have been developed; however, they are not perfectly optimized because they lack precise characterization for the timing details of the underlying ACA. In this paper, we investigate this promising direction by precisely characterizing the timing details of the EPC-Global G2 protocol and use it to derive a precise-optimal frame length model. The main objective of the model is to determine the optimal frame length value for the estimated number of tags that maximizes the performance of an RFID system. However, because precise estimation of the contending tags is difficult, we utilize a parametric-heuristic approach to maximize the system performance and propose two simple schemes based on the obtained optimal frame length-namely, Improved Dynamic-Frame Slotted Aloha (ID-FSA) and Exponential Random Partitioning-Frame Slotted Aloha (ERP-FSA). The ID-FSA scheme is based on the tag set estimation and frame size update mechanisms, whereas the ERP-FSA scheme adjusts the contending tag population in such a way that the applied frame size becomes optimal. The results of simulations conducted indicate that the ID-FSA scheme performs better than several well-known schemes in various conditions, while the ERP-FSA scheme performs well when the frame size is small.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.10
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• pp.1491-1497
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• 2013

Radio frequency identification (RFID) is an important and essential components of ubiquitous computing, with the development of wireless communication technologies and mobile computing environment. Recently, RFID becomes the mainstream application that helps fast handling and uniquely identifying the physical objects. It utilizes the electromagnetic energy for data transmission from a tag to a reader in the presence of arbitrary interference and noise. In order to employ the portable mobile RFID reader, a tag-collision problem between two or more adjacent tags should be considered. In this paper, we present the operation of RFID system in which numerous tags are present in the interrogation zone of a single reader at the same time. Since there may exist a number of tagged objects in the narrow area, multiple RFID tags may interfere each other, caused to degrade the data reliability and efficiency of the RFID system. In order to suppress interference signals from multiple neighboring tags, we present an application of Gold code for RFID communication system, which uses spread spectrum technique. In this RFID system, data bits are spreaded in each tags with the unique Gold code and the spreaded data bits are despreaded in the reader with the same Gold code. The performance analysis of the considered RFID anti-collision system is illustrated via computer simulation examples.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.4
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• pp.118-124
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• 2010

We proposed a goods load simulator for optimum RFID distribution, which includes experiment process modeling guidelines for stable RFID scan rate, efficient cost-reduction of RFID application or even speedy management of RFID field. We show verification of this simulator using field test of distribution, and the proposed simulator has better performance than the classic method, and demonstrate the proposed is efficient method of draw up guidelines on RFID distribution.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.4
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• pp.30-38
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• 2007

In this study, we propose an RFID based container terminal operation process. Field tests are conducted for 900 MHz (truck identification) tag and 433 MHz RFID (container identification/e-seal) tag at an Incheon container terminal to verify possibility of applying RFID in the container terminal gate. To evaluate effect of applying RFID in the container terminal operation, simulation models for current and RFID based container terminals are developed using ARENA. Simulations are carried out using industrial field data and the result indicates that performance of the container terminal can be prominently improved after RFID application.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.8 no.3
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• pp.144-151
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• 2009

In this paper, we consider various international and local standards and applied ontology concepts which are used in Semantic Web, to make more structured test methods/procedure. Based on the ontology concept, we classify test method as three categories (i.e., conformance test, interoperability test and performance test), and make test structures for each category. We believe that this research provides test methods which reflect various standards as well as the guidelines for users to construct RFID device software more structurally.

• 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.

• Journal of Magnetics
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• v.20 no.3
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• pp.295-301
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• 2015

We evaluated certain issues related to magnetic resonance imaging (MRI) coupled with the use of active 2.5 GHz radio frequency identification (RFID) tags for patient identification using low field (0.3 T) MRI and computed tomography (CT) scans. We also investigated the performance of the RFID reader located outside the MRI room by considering several factors. A total of ten active RFID tags were exposed to several MRI sequences and X-rays of CT scan. We found that only card type active RFID tags are suitable for patient identification purpose in MRI environment and both wristbands as well as card tags were suitable for the same in CT environment. Severe artifacts were found in the captured MRI and CT images when the area of the imaging was in proximity to the tags. No external factors affected the performance of active RFID reader stationed outside the MRI scan room.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.17-20
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• 2012

In the RFID system, A collision occurs when the multiple tags transmit at the concurrent in slot. Reduce conflicts, in order to maximize the efficiency of the system, the number of tags with the same number of slots are allocated. the number of slots to the next frame determined by the number of contention tags. In this paper, it estimate the number of tags based on the DFSA. Analyzed the performance of the system by the initial set number of tags through simulation.

• The KIPS Transactions:PartA
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• v.15A no.5
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• pp.287-294
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• 2008

A tag collision arbitration algorithm for RFID passive tags is one of the important issues for fast tag identification, since reader and tag have a shared wireless channel in RFID system. This paper suggests Hyper-Hybrid Query Tree algorithm to prevent the tag-collisions. The suggested algorithms determine the specified point in time for tag to transfer ID to reader by using value 1 of the upper 3 bit based on Query Tree. Also, because the transferred upper 3 bits of tag is different depending on the time of transfer, it is possible to predict in the suggested Algorithm. In the performance evaluation through simulation, it shows the suggested algorithm has higher performance in the number of queries compared to other Tree-based protocols.

• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.876-883
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• 2009

In 2008, Kim-Jun proposed RFID Mutual Authentication Protocol based on One-Time Random Numbers which are strong in Eavesdropping Attack, Spoofing attack and Replay attack. However, In 2009, Yoon-Yoo proved that it was weak in Replay attack and proposed a protocol which can prevent Replay attack. But Yoon-Yoo's protocol has problems that efficiency on communication and Brute-force attack. This paper shows weak points of Yoon-Yoo's protocol and proposes an RFID mutual authentication protocol with security and performance improvements.