• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.27 no.11
• /
• pp.972-977
• /
• 2016

This paper introduces development process and results of HF & UHF band(13.56 MHz, 920 MHz) tag antennas using a single-side printing method on a PE film. The size of tag antenna is designed in the area of $80mm{\times}50mm$, little bit smaller than a credit card. The UHF tag antenna, $76mm{\times}44mm$, is located at the outside of the card size tag antenna, and the HF tag antenna, $40 mm{\times}42 mm$, is located at the center of the UHF tag antenna. The UHF and HF tag antennas are designed with consideration of coupling effects. The single-side printing method with a jumper structure without using a via is used to make a loop antenna of HF tag antenna. The reading range of UHF tag antenna is about 6m, and the reading of HF tag antenna is about 5 cm. The designed tag antennas have long enough reading ranges for both bands. The tag is applicable to logistics and authentification.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.29 no.2
• /
• pp.93-98
• /
• 2018

This paper introduces the development of HF(NFC) and UHF band(13.56 MHz, 920 MHz) tag antennas, imbedded in a box. In dual band antennas, the HF band tag can be used to inspect the box using NFC, and the UHF band tag can be used for logistics. The dielectric constant of the box material is measured and used for simulation. The Ntag213 chip manufactured by NXP is used in HF loop antennas, since NFC is possible with Ntag213. For the UHF band, the Higgs-3 chip manufactured by Alien is used. The HF tag antenna is located at the center of the UHF tag antenna, and the location of the HF tag antenna is calculated while considering coupling effects. The designed tag can be used by both the bands for the purposes of logistics and authentication.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.2
• /
• pp.270-273
• /
• 2012

A plastic bolt shape UHF RFID tag has been developed for a live tree. The UHF tag is designed and installed into the head part of the bolt, inserted into a tree for management of tree. If the tag antenna is installed near the high dielectric constant material, the impedance of the tag antenna will be changed, and the tag does not work. Therefore, the dielectric constants of wood and plastic bolt are considered for tag antenna design. The input reflection coefficient characteristics and the reading range patterns are measured and compared. This UHF RFID tag can be applied into a live tree, and the status and location of tree can be controlled with the RFID tag. This developed UHF tag can be applied to any applications and objects using a bolt.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.9
• /
• pp.823-828
• /
• 2009

A small UHF RFID tag antenna for a key-chain installed inside of a metallic key-management cabinet has been designed. The tag antenna has been designed as small size as $66\;mm{\times}6\;mm$ with consideration of coupling among the tag antennas and metallic parts of key-chain and cabinet. The tag antenna is fabricated with a meander line dipole using T-matching method with FR-4 substrate. One tag antenna has been designed with consideration of coupling of adjacent tag antennas, and the other has been designed for the location close to the metallic part in the cabinet. The characteristics of tag antennas and reading distance have been analyzed based on the different numbers of adjacent tag antennas. As a results, the 360 tag antennas installed in the cabinet have been successfully recognized.

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

• Journal of Navigation and Port Research
• /
• v.32 no.5
• /
• pp.363-368
• /
• 2008

This paper presents a miniaturization design technique of radio frequency identification (RFID) tag antenna operated in 910 MHz band. Miniaturization structure design for a tag antenna is performed by structure application of the folded dipole and meander line. In order to realize the maximum power transmission, imaginary part of a chip impedance and a tag antenna impedance is matched by complex conjugate number. The optimized tag antenna size is $50\;nm\;{\times}\;40\;nm\;{\times}\;1.6\;nm$ and its size is reduced about 62 % comparison with antenna size of reference [4]. The measured results of fabricated tag antenna are confirmed the reasonable agreement with prediction. The read range of the tag antenna with chip observed about 5 m.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.48 no.1
• /
• pp.102-107
• /
• 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 Communications and Information Sciences
• /
• v.35 no.7B
• /
• pp.1081-1090
• /
• 2010

$0.18{\mu}m$ CMOS UHF RFID tag frontend is presented in this paper. Several key components are highlighted: the voltage multiplier based on the threshold voltage terminated circuit, the demodulator using current mode, and the clock generator. For standard compliance, all designed components are under the EPC Global Class-1 Generation-2 UHF RFID protocol. Backscatter modulation uses the pulse width modulation scheme. Overall performance of the proposed tag chip was verified with the evaluation board. Prototype Tag Chip dimension is neary 0.77mm2 ; According to the simulation results, the reader can successfully interrogate the tag within 1.5m. where the tag consumes the power about $71{\mu}W$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.18 no.11
• /
• pp.1211-1216
• /
• 2007

Yagi-Uda UHF RFID(Radio Frequency Identification) tag antennas with long reading range have been designed. According to ISO-18000, EIRP(Effective Isotropic Radiation Power) of reader and reader antenna is limited as 36 dBm. Therefore, the gain of a tag antenna should be high enough to extend the reading range. Yagi-Uda antenna has been applied to a UHF RFID tag antenna, and high gain and long reading range have been achieved. Three different of Yagi-Uda UHF antennas have been optimized to achieve the small size with low back-lobe patterns. The sizes, reading ranges and return loss of Yagi-Uda tag antennas are compared and measured.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.515-520
• /
• 2009

This paper presents the software design of RFID Educational system based on using 900MHz air interface between the reader and the tag. Software of the reader and active tag is developed on embedded environment and the software of PC controlling the reader is on window OS. ATmega128 processor is used for H/W of the reader and active tag, and C language is used for their developing. Programming on window OS used MFC. Main functions of this system are to control tag containing EPC global Data by PC through the reader, to obtain information of tag through the internet and to read/write data on tag memory. Software design of 900MHz RFID educational system is done on the basis of these functions.