• 프린팅코리아
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• v.7 no.8
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• pp.38-43
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• 2008

RFID(Radio Frequency Identification)는 IC칩과 무선을 통해 식품, 동물, 사물 등 다양한 개체의 정보를 관리할 수 있는 첨단 인식 기술이다. 기존에 널리 사용되고 있는 바코드가 일정한 방향으로 인쇄된 내용을 리더기를 이용해야만 인식하는데 비하면 RFID는 초소형칩(IC)을 내장해 무선 주파수로 추적하기 때문에 인식범위가 넓고 인식 속도 역시 매우 빠르다. 뿐만 아니라 담을 수 있는 정보량에서도 모델에 따른 차이는 있지만 바코드와는 비교가 되지 않을 정도로 많다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.6C
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• pp.626-633
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• 2009

ISO/IEC/WD 24753 defines new modem specifications for a long-range RFID communications and application protocol for a sensor tag system. According to the standard, the frequency offset of the tag is 4%. In general wireless communications systems, it is known that a coherent receiver is superior to a non-coherent receiver. However, if the frequency offset is large, it is difficult to restore the original data accurately with a coherent receiver, and the performance of a coherent receiver is easily degraded. In this paper, a non-coherent receiver structure is adopted to solve the frequency offset problem of long-range RFID communications. We designed a frequency estimation block to find an optimal frequency from the received signal with 4% frequency offset and proposed a start frame delimiter (SFD) detection algorithm to determine the start position of the payload. The frequency estimation block finds the optimal frequency from the received signal using 9-correlators. And the SFD detection block searches the received signal to find the start position of the payload with dual correlator. We implemented a long-range RFID reader with the proposed methods and evaluated its performance in a wired/wireless test network. The implemented long-range RFID reader showed more superior performance than the commercial RFID reader in terms of recognition range.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.8
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• pp.79-85
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• 2004

In this paper, the RF-ID system for ubiquitous tagging applications has been designed, fabricated and analysed. The RF-ID System consists of passive RF-ID Tag and Reader. The passive RF-ID tag consists of rectifier using zero-bias schottky diode which converts RF power into DC power, ID chip, ASK modulator using bipolar transistor and slot loop antenna. We suggest an ASK undulation method using a bipolar transistor to compensate the disadvantage of the conventional PIN diode, which needs large current Also, the slot loop antenna with wider bandwidth than that of the conventional patch antenna is suggested The RF-ID reader consist of patch array antenna, Tx/Rx part and ASK demodulator. We have designed the RF-ID System using EM and circuit simulation tools. According to the measured results, The power level of modulation signal at 1 m from passive RF-ID Tag is -46.76 dBm and frequency of it is 57.2 KHz. The transmitting power of RF-ID reader was 500 mW

• The Journal of the Korea Contents Association
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• v.9 no.1
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• pp.62-72
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• 2009

In this paper, we propose an application of RFID(Radio Frequency Identification) tag to food wastes disposal system of Cheongju city. The existing system of Cheongju city is monthly fixed amount levy system. The weak point of this system must pay a same commission in spite of each other different food wastes quantity. Also the accurate occurrence quantity of the food wastes and present condition grasp of control are impossible. It will not be able to reflect to a policy decision because does not manage the control of the food waste efficiently. On the other hand, when a food wastes measuring system using RFID is executed tag, it will manage and analyze automatically the obtained data. And collecting, transporting and handling of the food wastes come to be very easy. Also the reproduction and embezzlement of the tag are impossible. As a result of this system, it brings the decrement of the food waste. Therefore the economic effect could be come true and the food wastes is controlled environment-friendly. The food wastes disposal system using RFID tag will be able to contribute in u-city constructions with RFID/USN technology which pursues from the government.

• Aerospace Engineering and Technology
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• v.7 no.1
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• pp.236-244
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• 2008

The evolution and application of RFID technologies have been at the forefront of allowing aviation industries to improve the quality of aircraft maintenance and air cargo handling. However, safety problems in airplane operation are arising from the hazards of frequencies transmitted due to RFID systems. Though the intensities of frequencies back-scattered from the tags are very weak, some malfunctions are anticipated due to induction coupling on aircraft wiring. Therefore, safety assessment such as electromagnetic compatability should be accomplished upon aircraft critical and essential equipments before installations.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1007-1010
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• 2005

RFID(Radio Frequency IDentification)란 일정(무선) 주파수 대역을 이용한 자동인식기술로 원거리에서도 대상물을 분석하여 개체의 정보를 읽거나 기록할 수 있는 시스템이다. 현재 RFID기술은 바탕으로 한 유비쿼터스(Ubiquitous)환경 및 물류시스템, 바코드 시스템을 사용하기 힘든 동물 태깅이나 고속도로 요금부과, 도난 방지, 치매환자의 보호관리 등에 사용할 수 있다는 점으로 사회 전반에 걸쳐 그 사용 폭을 넓혀 가고 있다. 그러나 RFID의 낮은 연산능력과 기억능력의 특징상 정보 보안이나 개인의 프라이버시측면에서 여러 문제들을 발생시킨다. 본 논문에서는 기존의 RFID 인증 프로토콜들을 비교 분석하고, 태그와 리더기 사이의 정보 전송 중 공격자에 의한 정보의 변형을 방지하는 RFID 인증 프로토콜을 제안한다.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.3
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• pp.1-7
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• 2007

RFID ( Radio Frequency IDentification ) is an automatic realization technology that recognizes things or a person with data stored tag, card, label, etc that have microchip by using radio frequency. Automation and efficient data base management(DBM) of system are possible by replaces using Bar-code that is used widely with using RFID. In this paper, we designed RFID tag data format that used to recognize information of books in Library and implemented library management system. Library management system is divided checking collection of books, self-loaning books system, self-returning books system, management books information system for a librarian. RFID leader realized information of tag and transfer it to host computer through RS-232 interface. Host computer processes and operates information with middleware. System that we made is depending on executive system for a librarian.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.10
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• pp.45-52
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• 2008

We investigated the design of an RF-powered, wireless temperature sensor tag chip using $0.18-{\mu}m$ CMOS technology. The transponder generates its own power supply from small incident RF signal using Schottky diodes in voltage multiplier. Ambient temperature is measured using a new low-power temperature-to-voltage converter, and an 8-bit single-slope ADC converts the measured voltage to digital data. ASK demodulator and digital control are combined to identify unique transponder (ID) sent by base station for multi-transponder applications. The measurement of the temperature sensor tag chip showed a resolution of $0.64^{\circ}C/LSB$ in the range from $20^{\circ}C$ to $100^{\circ}C$, which is suitable for environmental temperature monitoring. The chip size is $1.1{\times}0.34mm^2$, and operates at clock frequency of 100 kHz while consuming $64{\mu}W$ power. The temperature sensor required a -11 dBm RF input power, supported a conversion rate of 12.5 k-samples/sec, and a maximum error of $0.5^{\circ}C$.