• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.9
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• pp.971-978
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• 2010

In this paper, we propose a compact multiple meander RFID tag antenna with broadband characteristic. The proposed tag antenna has been designed using the multiple meander form to effectively minimize the U-shaped half wavelength dipole antenna as the radiator part. The commercial tag chip is attached to the upper center of the rectangular shaped feed for impedance matching. The size of the antenna is $20{\times}19.7\;mm^2$ and VSWR<5.8 bandwidth is 855~964 MHz which covers the world UHF RFID bandwidth.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.5
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• pp.46-51
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• 2013

In this paper, a dual-band antenna is proposed for the RF power harvester system as well as RFID tag. The proposed antenna operates as the passive and active RFID tag antenna in the UHF and microwave band, respectively. In addition, to charge the battery of an active RFID tag in the microwave band, it harvest the RF signal for tagging from the passive RFID tag antenna in the UHF band. The proposed antenna operates in the UHF band (917~923.5 MHz) and microwave band (2.4~2.45 GHz). In order to obtain the dual-band operation, the dipole structure and meander parasitic elements are proposed as the ${\lambda}/2$ and $1{\lambda}$ dipole antenna, respectively. The radiating dipole structure in the microwave band acts as the coupled feed for the meander parasitic elements in the UHF band. The impedance bandwidth (VSWR < 2) of the proposed antenna covers 917~923.5 MHz (UHF band) and 2.4~2.45 GHz (Microwave band). Measured total efficiencies are over 45 % in the UHF band and over 70 % in the microwave band. Peak gains are over 0.18 dBi and 2.8 dBi in the UHF and microwave band with an omni-directional radiation pattern, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.8 s.99
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• pp.797-802
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• 2005

In this paper, we design a UHF band RFID tag antenna which is conjugate matched to an impedance of a chip and also mountable on conductive materials. The proposed tag antenna is very compact($50{\times}30{\times}4mm$) with a modified PIFA shape. The proposed tag antenna has an advantage of easy matching to various chip input impedances. The performance of the antenna is evaluated by monitoring RCS in the reader direction. The RCS of the designed tag is $-10.2\;dBm^2$ when the chip is shorted and is $-21\;dBm^2$ when the chip impedance is a complex conjugate of the antenna impedance.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.2
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• pp.249-254
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• 2014

We have studied on the possibility of railway stability system using RFID tag. UHF RFID tag was desinged, manufactured and tested. Proposed UHF tag antenna has PIFA type structure and inset feed multi matching technique was attempted for impedance matching of antenna. The impedance bandwidth (VSWR < 3) of the proposed tag antenna covers 917~923 MHz. Measured peak gain is 3.225 dBi and UHF band with an omni-directional radiation pattern. RFID reader and tag installed in motor car and track, respectively. Then, tag recognition rate according to velocity of car (under 45 km/h) represented 100 %.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.263-268
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• 2010

This paper shows the key management system in a small metallic cabinet using a small UHF RFID tags. Each key chain with a key has a custom-designed small RFID tag antenna. There are 6 metallic racks in the small cabinet, and each rack can hold 60 key chains. Therefore, the small cabinet can hold 360 key chains with tags. The 360 key chains with RFID tags in a cabinet are recognized by RFID key chain management system. Even though it is hard to recognize 360 tags in the a cabinet, this RFID key management system with small custom designed RFID tags can recognize all the tags in the small cabinet. To read the all the tags, the locations of antennas and tag shapes are optimized. The reading rates based on the bios-version of the reader and the locations of the reader antennas are compared.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.1
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• pp.68-75
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• 2007

A single chip NFC transceiver supporting not only NFC active and passive mode but also 13.56MHz RFID reader and tag mode was designed and fabricated. The proposed NFC transceiver can operate as a RFID tag even without external power supply which has dual antenna structure for initiator and target. The area increment due to additional target antenna is negligible because the target antenna is constructed by using a shielding layer of initiator antenna. The analog front end circuit of the proposed NFC transceiver consists of a transmitter and receiver of reader/writer block supporting NFC initiator or RFID reader mode, and a tag circuit for target of passive NFC mode or RFID tag mode. The maximum baud rate of the proposed NFC device is 212kbps by using UART serial interface. The chip has been designed and fabricated using a Magnachip's $0.35{\mu}m$ double poly 4-metal CMOS process, and the effective area of the chip is 2200um by 3600um.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.1
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• pp.102-107
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• 2011

The current blood control system is using barcode and scanning one by one to manage blood bags. To have better management and accuracy, an RFID BIS (blood information system) is implemented with an UHF RFID tag antenna using a reflecter for a blood bag has been used.. The UHF RFID tag for blood bag, attached on the high permittivity blood, is designed and fabricated. The tag antenna is optimized and fabricated with the simulation tests such as the existence and nonexistence of the reflector, various distance between the reflector and the dipole tag, the different widths of the reflector and the existence and nonexistence of the T-matching structure. The characteristics and the reading range patterns of the tag antennas are measured. The BIS is implemented with the new tag design.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.3
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• pp.209-214
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• 2019

This paper presents the design of a 920 MHz ultra-high frequency(UHF) band radio frequency identification(RFID) conductive fabric tag antenna. The resistance values of four different conductive fabrics are measured, and the conductivities of the fabrics are calculated. The fabric with the best conductivity is selected, and the best conductivity of the fabric is used to simulate the fabric tag antenna design. The fabric UHF RFID tag antenna with a T-Matching structure and name-tag size of $80{\times}40mm$ is simulated and designed. The simulated and measured results are compared, and a laundry test is performed. The reading range of the fabric tag antenna is about 2 m. This fabric tag can be easily applied to an entrance control system as it can be attached to other fabrics and cloths.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.79-82
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• 2006

최근 사물에 태그를 부착하여 무선으로 사물과 주변의 정보를 감지하는 RFID 기술이 등장하여 IT시장을 선도할 기술로 주목받고 있다. 그 중 국내에서 아마추어용으로 사용되던 433MHz대역이 컨테이너용 RFID 대역으로 지정되면서 국내에서도 활발히 연구가 이루어지고 있으며, 부산항에서 시범 운영하고 있으며 향후 확대 운영할 계획에 있다. 이에 본 논문에서는 프랙탈 이론을 적용하여 433MHz대역의 RFID 태그 안테나를 설계 및 제작하였다. 프랙탈 이론 중 민코스키 곡선을 응용하였고, 중심에 미앤더를 둔 구조로 설계하였다. 또한 접지면을 안테나와 같은 면에 구조로 최종 설계하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.12B
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• pp.1468-1474
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• 2009

This paper shows an UHF RFID metallic tags using a Cavity structure for a long reading range. The reading range of a general passive tag is limited because the EIRP of a reader system is limited as 36㏈m by ISO 18000-6. To extend the reading range, the tag antenna should have a high gain antenna structure. The designed tag antenna is recognized over 10m range with a Cavity structure. The directivity pattern and the performance of the tag with the Cavity structure is stable when it is attached to a metallic object. The designed tag antenna has two kinds as cavity thickness. The sizes of designed tag antennas are $176\;{\times}\;52\;{\times}\;10\;mm$ and $176\;{\times}\;61\;{\times}\;30mm$ They can be attached to a large metallic materials and heavy equipments. The measured reading ranges of the tags are about 11m and 15m when they are attached to a metallic object.