• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3614-3619
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• 2022

To operate the ion cyclotron resonance heating (ICRH) antennas in a better heating state and produce relatively low impurities, it is necessary to control the antenna spectrum by changing the antenna phasing. As the electrical length of the antenna feeding transmission lines is changing as a matter of the standing wave pattern at the ceramic supports, 90° elbows, T-connectors and antenna loops, we chose to measure the current at the grounding points of the antenna loops by antenna strap probe. The voltage drops along a small, several millimeter-long paths at the end of the antenna loops give a signal that is proportional to the current in the antenna loop. Through the simulation of the antenna strap probe and the actual measurement of the antenna phasing under vacuum conditions, the reliability of the antenna strap probe based diagnostic system have been successfully proved. Moreover, this system was successfully applied to the ICRH daily experiments in the spring of 2021. In the near future, the active real-time feedback control of the antenna phasing system will be developed based on this diagnostic system in the EAST tokamak.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3A
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• pp.417-423
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• 2000

A broadband antenna available in the range of 30MHz for electromagnetic interference (EMI) test is proposed in this paper, This antenna is configurated in a disk-loaded cylindrical dipole (DLCD) connected to an 180。 hybrid balun consisting of two coaxial feeders. The performance of EMI antenna is characterized with its accurate antenna factor. The antenna factor for this antenna is obtained by using the method of moments and the calculated results are compared with the measured ones. Normalized site attenuation (NSA) is also measured by using this antenna. The results present that the propose antenna could be used for a reference antenna having measurement reproducibility and represented by a theoretically accurate analysing model in EMI measurement.

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.4
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• pp.170-175
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• 2004

A three dimensional feed horn 10${\mu}{\textrm}{m}$ wavelength infrared antenna has been suggested, fabricated and characterized. It was applied to an infrared detector for efficient collecting of IR radiation and for reducing background noise. The horn antenna size was designed for maximum antenna directivity. The 3D feed horn antenna mold was fabricated using rotating and tilted illumination while the antenna plate was constructed by way of electroplating. Antenna characteristics were measured by coupling with a microbolometer. Measurement results indicated that the directivity of the antenna is 16.1㏈ and the background noise is reduced by approximately two times.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.9
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• pp.932-936
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• 2002

This paper has been studied a calibration techniques in CISPR A for 1 m monopole antenna factor in the frequency range below 30 MHz. The equivalent capacitance substitution method uses a dummy antenna in place of the actual rod element. Dummy antenna measure frequency from 150 kHz to 30 MHz and good results factor from 150 kHz to 25 MHz compare to using 1 m monopole antenna factor. It will be use to substitute dummy antenna factor for 1 m monopole antenna factor.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.3
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• pp.175-181
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• 2004

In order to increase the coupling efficiency of the Power and Phase of the active Phase way antenna, we have fabricated the active phased-array antenna which is coupled by the transmission line, and investigated the relationship between the length of the coupling transmission line and coupling power and phase. The following three types of driving method -(1) giving the frequency difference between the two active antenna, (2) applying the input signal to the one side of the two antennas, and changing the eigen frequency of the other side antenna, (3) appling the different phase inputs to the active antennas was investigated. The experimental results showed that the interval of the antenna elements has not affected the power and the phase of the antenna.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.525-528
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• 2005

The tracking antenna system must be always pointed to target moving vehicle. Especially, for an antenna mounted on a movable vehicle, it needs the stabilized antenna system. In this paper, two types of fuzzy controller were derived and applied to a data link antenna system and the altitude control of unmanned helicopter, respectively. A simplified Fuzzy-PID controller was designed for 2-axes antenna stabilization and tracking system and the performance was verified by simulations and experiments. Computer simulations were performed by Matlab and SIMULINK. A 2-Axes antenna (SeaTel 1898 model) was selected as test platform of this research. The antenna was modified by using two Blushless Direct Current motors and an embedded DSP controller. To verify the performance of designed antenna servo control system, the performance of the conventional PID controller and that of the Fuzzy-PID controller, designed by the same PID control gains, were compared.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.802-805
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• 2003

Structural surface becomes an antenna. The integration of antennas into structural body panels is a new high payoff technology. It emerged from the need to improve structural efficiency and antenna performance. In this paper, we developed new design concept for the structural surface which transmits and receives the electromagnetic signals, and it is termed Surface-Antenna-Structure (SAS). Design procedure was presented including structure design. material selection and design of antenna elements, which was processed according to the communication with KORSAT satellite at Ku-Band (12.25-12.75 GHz). The final demonstration article was 350$\times$200$\times$7.5mm flat antenna panel. Experimental results for antenna performances were in good agreements with design requirements. Also structural analysis was performed with SAS. estimating stress distributions under simply supported condition with Laminated Plate Theories and Wavier Solutions. The SAS concept can be extended to give a useful guide to manufacturers of structural body panels as well as antenna designers. promising innovative future communication technology.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.2
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• pp.11-15
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• 2013

We in order to use WLAN communication device planned wireless USB dongle internal antenna of 2.4 GHz/5.8 GHz band. So it uses square patch dual-wideband and quality is satisfactory and it designed print folded monopole antenna of the shape which is simple. The thickness of the antenna was fed by a $50{\Omega}$ coaxial cable feeding 1mm dielectric constant 4.4 FR4 substrate was used. The overall size of the antenna is $20mm{\times}50mm$. So the internal antenna is suitable. Measurement results of the fabricated antenna, the return loss of more than 10 dB in the two bands could be obtained. Radiation pattern has a maximum gain of 3.75 dBi value.

• International journal of advanced smart convergence
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• v.1 no.1
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• pp.1-5
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• 2012

We propose a structure for a multiple input multiple output antenna which has no space for isolation. The antenna operates in a frequency range of 2.4-2.48 GHz and can achieve a high channel capability as a Bluetooth antenna. The MIMO antenna consists of two planar inverted F antennas with symmetric structure. We designed the proposed antenna using HFSS simulator, and we designed the fabricated antenna using PCB fabricator. The MIMO antenna's isolation $S_{21}{\leq}-10dB$ and reflection coefficient $S_{11}{\leq}-20dB$. The proposed antenna's specification satisfies Bluetooth antenna's criteria and has more space than the existing MIMO antennas, which have space for isolation.

• Journal of electromagnetic engineering and science
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• v.17 no.4
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• pp.233-237
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• 2017

In this paper, a dual-band high frequency (HF) and ultra-high frequency (UHF) radio-frequency identification (RFID) tag antenna is presented that operates in the 13.56 MHz band as well as in the 920 MHz band. A spiral coil along the edges of the antenna substrate is designed to handle the HF band, and a novel meander open complementary split ring resonator (MOCSRR) dipole antenna is utilized to generate the UHF band. The dual-band antenna is supported by a single-feeding port for mono-chip RFID applications. The antenna is fabricated using an FR4 substrate to verify theoretical and simulation designs, and it has compact dimensions of $80mm{\times}40mm{\times}0.8mm$. The proposed antenna also has an omnidirectional characteristic with a gain of approximately 1 dBi.