• Journal of the Korean Society for Railway
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• v.4 no.3
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• pp.102-109
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• 2001

In this paper, it has a proposal of the RFID reader antenna design that expand the dedicated short-range communication distance between a static object on the ground and a mobile object attached on the moving article. The static reader equipped with micro-processor makes it possible to have a serial communication with a main system, so that much data can be transfer to the main system. An antenna is adjusted in order to a communication, the scale is designed by results values of simulation using matlab. It is achieved to systematically manage logistics, person resource and security system by grasping the information and location of mobile object on the basis that this system receives the information between a static reader and a mobile object tag at 134.2kHz band on real time, also to make it possible the main system to process. Therefore, the reader antenna scale is controlled on the foundation of a magnetic field theory in order to expand a recognition distance of reader and tag, so that can be optimistically recognized with minimizing the direction influence of reader and tag.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.5
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• pp.776-796
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• 2010

Integrated RFID-WSNs (wireless sensor networks) have recently been researched to provide object identities, sensing information, mobile service, and network functionalities. In integrated RFID-WSNs, the reader collision is one of the critical problems. Above all, due to the absence of universally applicable anti-collision protocols and the channel capture phenomenon, the medium access control protocols in integrated RFID-WSNs suffer from reader collision and starvation problems. In this paper, we propose an efficient MAC protocol, called EMP, to avoid the above problems in integrated RFID-WSNs. EMP is a CSMA-based MAC protocol which is compatible with sensor networks operating on integrated nodes which consist of an RFID reader and a senor node. EMP resolves not only the reader collision problem, but also the starvation problem using a power control mechanism. To verify the performance of EMP, we compared it with other anti-reader collision MAC protocols using simulations. As a result, the performance of EMP showed improvements in throughput, system efficiency, and energy consumption compared to the single data channel protocols (CSMA/CA, Pulse, and DiCa) in dense deployment environments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2805-2810
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• 2010

The Passive Device called SAW Device of the ID Tag or a small sensor that can replace all of MEMS technology Micro Device. When using SAW Device will be able to replace that sensor control the power needed or separate space. Enlarge the scope of this advantage to use as a platform for various SAW Device is required. However, the current SAW Sensor development has many, but SAW Sensor that can leverage the platform's development is sketchy. Therefore, this paper implements SAW Reader can be measured in SAW Device Using an FPGA more simple and efficient Reader platform.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.141-142
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• 2018

본 발표문은 서두수의 Korean Literary Reader(1965)를 소개하고 영어를 중심으로 쓰인 한국문학 교과서로서의 면모를 파악하는 것을 목적으로 한다. '영어로 쓰인'이 아닌 '영어를 중심으로 쓰인'이라는 수식을 붙인 이유는 한국문학에 대한 개략적인 역사는 영어로 서술되었지만, 한글로 된 원문을 수록한 본문에서는 어렵거나 생소한 단어만 영어로 주석을 달았기 때문이다. 따라서 완전히 영어로만 서술된 한국문학 교과서라고는 할 수 없다. 하지만 Korean Literary Reader(1965)를 통해 초창기 미국-한국문학 교과서의 형태를 살필 수 있다는 점에서 의미가 있다고 하겠다. 또한 저자 서두수의 행적 안에서 미국에서 이 책을 발간한 목적 중 몇 가지를 유추하는 것으로 발표를 마친다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.447-450
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• 2010

SAW Device 라는 Passive 소자는 ID Tag나 소형센서들을 대체할 수 있는 MEMS 기술의 초소형 Device 다. 이 SAW Device를 이용하면 독립된 공간이나 전원이 필요한 센서 제어 등을 대신할 수 있을 것이다. 이렇게 활용범위가 확대됨에 따라 다양한 SAW Device를 사용하기 위한 플랫폼이 요구된다. 하지만 현재 SAW Sensor는 많은 발전을 해왔지만 SAW Sensor를 활용할 수 있는 플랫폼의 발전은 미흡하기 때문에 본 논문에서는 이러한 SAW Device를 측정할 수 있는 SAW Reader를 FPGA를 이용하여 좀 더 간단하고 효율적인 Reader platform을 구현해 보고자 한다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.2 s.344
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• pp.27-38
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• 2006

When an RFID reader attempts to read tags, interference might occur if the neighboring readers also attempt to communicate with the same tag at the same time or the neighboring readers use the same frequency at the same time. These interferences cause the RFID reader collision. When the RFID reader collision occirs, either the command from the reader can not be transmitted to the tags or the response from the tags can not be received by the reader correctly. RFID reader anti-collision algorithms have been developed to reduce it. One of the best blown reader anti-collision algorithms is the Colorwave algorithm proposed by MIT. The Colorwave algorithm reduces the reader collisions by having the readers operate at different times. In Colorwave the time is divided into frames and a frame is divided into a number of slots. Each reader can access the tags using the slot time assigned to it. Depending on the probability of the interference, the colorwave adjusts the frame size to improve the efficiency. In this paper, we analyze the operations and the performance of the Colorwave algorithm and identify the problems of the algorithm. We also show that by adding some modifications to the algorithm the performance can be improved significantly.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.7
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• pp.731-738
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• 2007

Recently UHF RFID system has drawn a great deal of attention because of its potential to revolutionize supply chain management. In this article, RFID reader-to-reader interference is analyzed in terms of interrogation range. For evaluating RFID interference quantitatively, the new figure-of-merit, IRRR, is defined. In order to show the usefulness of IRRR, calculated IRRR is verified by measurement using two RFID readers and a tag in multiple-reader environment. IRRR can be referred to an important design parameter to analyze more complex interfering problems in actual RFID system deployments.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.491-497
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• 2015

In this paper a method of design and Implementation of RFID based control system for reducing standby power consumption at the power outlet is described. The system is composed of a RF controlled power outlet having relay and an active RFID tag communicating with the RF reader module controlling the relay. When the tag carried by human approaches to the RF reader the reader recognizes the tag and switch off the relay based on the RSSI level measurement. A low power packet prediction algorithm has been used to decrease the DC power consumption at both the tag and the RF reader. The result of experiment shows that successful operation of the relay control has been obtained while low power operation of the tag and the reader is achieved using above algorithm. Also setting the distance between the reader and the tag by controlling transmission power of the tag and adjusting the duty cycle of the packet waiting time when the reader is in idle state allows us to reduce DC power consumption at both the reader and the tag.

• 전자공학회논문지 IE
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• v.48 no.4
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• pp.40-46
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• 2011

In this paper, we introduce a hybrid RFID reader to recognize the pets. There is no the RFID reader to recognize a different types of frequency simultaneously. The RFID reader with 134.2 KHz has disadvantages with limited recognition radius and direction. The developed reader is dual-frequency RFID reader (134.2 KHz, 13.56 MHz) that is capable of identifying the pets with a different types of tags. The prototype model in the field test shows that the recognition coverage increases compared to the imported reader.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10A
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• pp.987-996
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• 2008

In this paper, the conventional anti-collision algorithms, such as Channel Monitoring algorithm and Pulse Protocol algorithm are analyzed. To decrease tag identification time, and increase system throughput and efficiency, we propose a new reader anti-collision algorithm, Pulse Protocol-based Hybrid Reader Anti-collision Algorithm, using Slot-occupied Probability under dense reader environment. The proposed algorithm uses Slot-occupied Probability to improve the performance of Pulse Protocol Algorithm. That is, A reader checks Slot-occupied Probability after generating random backoff time. If Slot-occupied Probability is greater than 0, it uses another new random backoff time to avoid reader collision. We also compare the performance of the proposed algorithm with those of Channel Monitoring and Pulse Protocol algorithms in respect of identification time system throughput, and system efficiency. Simulation results show that the proposed algorithm has an increment of 5% of identification time and system throughput as increasing the number of readers.