• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.60-64
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• 1997

The design process and construction method of a strip line is described for measuring radiated susceptibility of vehicular components having electrical cables more than 2 min length. he characteristic impedance of the trip line was determined 90$\Omega$ to obtain the field uniformity of $\leq$${\pm}$3 dB in the frequency range from 100 kHz to 500 MHz. Tapered coaxial lines were used instead of the traditional lumped circuit element for the impedence matching units, therefore, the strip line has high power capability. Using these techniques, the field uniformity and power capability of a strip line could be considerably improved.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.2
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• pp.266-271
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• 2014

The Electromagnetic Interference(EMI) generating from corona discharge of transformer area can interference the digital Instrument and Control(I&C) systems located nearby transformers. When the potential gradient of the electric field around the conductor is high enough to form a conductive region but not high enough to cause electrical breakdown to nearby objects, the EMI of corona discharge emits with the conducted and radiated noise and it interferences the signals of the I&C systems. Since digital I&C systems have an efficiency and competitive price, the analog I&C systems have been upgraded and displaced with the digital I&C systems but which have less EMI Immunity. There was no assessment to I&C systems by EMI generating corona discharge nearby transformers. When the safety-related I&C systems are installed in plants, the verification of equipment EMI should be done not in site-specific test but in test facilities. There are the need to do the site-specific EMI evaluation of corona discharge nearby transformers. This paper assesses the margin between plant emission limits and the highest composite plant emission of corona. When the non safety-related I&C systems are placed in transformer area, it suggests the appropriate radiated susceptibility level to EMI of corona discharge.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.220-227
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• 2011

With the rapid development of mobile communication technology, the technologies based on the diverse digital modulation schemes have been used for the frequency range of over 800 MHz. The only radiation immunity has been tested using only AM signal based on IEC 61000-4-3 without any consideration of the influence of electromagnetic radiation in Korea. However, it has not been tested by wideband digital modulation signals such as cdmaone(IS-95), WCDMA and PM signal. The purpose of this study was to review the standards. In addition, the input signals were analyzed and tested considering the environments in Korea. The results showed that the devices were influenced by digital modulation signal or PM signal more than by AM signal.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.51-59
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• 2023

The tracking radar system is installed and operated on the ground, ships, and aircraft, and requires a design to withstand electromagnetic interference with nearby electronic devices. In this case, radiation and immunity standards for cable connection must be satisfied to prevent malfunction of other equipment due to electromagnetic wave interference caused by cables connected to the tracking radar. The radiation standard must also be satisfied so that the electromagnetic wave noise generated and radiated from the tracking radar does not affect the peripheral device, so that the immunity standard for the electromagnetic wave emitted from the peripheral device must be satisfied. In this paper, we propose a design to satisfy MIL-STD-461G including CE, CS, RE, and RS, and explain design satisfaction through tests.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.3
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• pp.130-137
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• 2015

This study is about the controller development of the Electric Operating Cell(EOC) which will replace the Mechanical Operated Cell(MOC) of the vacuum circuit breaker which has been used in the power plant and the performance test for the developed controller. The controller developed through this study was manufactured considering the harsh installation environment and electrical condition of the power plant, and the controller performance certification test for confirming the product reliability was taken to know whether or not to withstand fully in various electrical and mechanical problems. Items for performance certification test were AC power frequency voltage withstand test, combined surge immunity test, 1 [MHz] oscillatory SWC test, fast transient SWC test, radiated electromagnetic interference test, vibration test. As a result, all tests has passed an examination without malfunction.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.11a
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• pp.408-413
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• 1998

Electromagnetic wave absorbers for anechoic chamber are needed to broaden the useful frequency bandwidth, reduce the thickness, and decrease the weight. There are various absorbers proposed for the above conditions, but they could not decisively solve it the alone requirements. The Electromagnetic wave absorber made by a conventional ferrite tile has, for example, broadened the useful frequency bandwidth by the way of forming air layer(practically use urethane foam, etc.) on the ferrite tile. Therefore, an air layer is formed between a reflection plate and a sintered Ni-Zn ferrite tile of 7 mm in thickness, which has reflectivity less than -20 dB from 30 MHz to 600 MHz in bandwidth. Accordingly, in this paper, a broadened electromagnetic wave absorber will be designed, which has the reflection characteristics less than -20 dB from 30 MHz to 6000 MHz in the bandwidth. Then we will design a super broadband electromagnetic wave absorber by inserting square Ferrite Cylinders Type with the thickness less than 11 m and with the frequency band from 30 MHz to 6000 MHz under the above tolerance limits. The purpose of this research is on the development of a universal anechoic chamber for measuring radiated electromagnetic wave or immunity of electronic equipments, GTEM-cell, wall material for prevention TV ghost, etc.

• Journal of the Korean Institute of Navigation
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• v.22 no.4
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• pp.51-57
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• 1998

According to the rapid development of the electric industry, the demand of the frequency allocation and the usage of electromagnetic wave are increased due to automation of modem society. Electromagnetic wave absorbers for anechoic chamber are needed to broaden the effective frequency bandwidth, reduce the thickness, and decrease the weight. There are various absorbers proposed for the above conditions, but they could not decisively solve the above requirements. The Electromagnetic wave absorber made by a conventional ferrite tile has, for example, broadened the effective frequency bandwidth by the way of forming air layer(practically in urethane foam, etc.) on the ferrite tile. Therefore, an air layer is formed between a reflection plate and a sintered Ni-Zn ferrite tile of 7 mm in thickness, which has reflectivity less than -20 dB from 30 MHz to 400 MHz in bandwidth. In this paper, a broadband electromagnetic wave absorber are designed, which has the reflection characteristics less than -20 dB from 30 MHz to 8,000 MHz in the bandwidth. A super broadband electromagnetic wave absorber is achieved by inserting square Ferrite Cylinders Type with the thickness less than 23.5 mm and with the frequency band from 30 MHz to 8,000 MHz under the above tolerance limits. The purpose of this research is on the development of a universal anechoic chamber for measuring radiated electromagnetic wave or immunity of electronic equipments, GTEM-cell and also a wall material for preventing TV ghost, etc.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.1
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• pp.43-50
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• 1999

Electromagnetic wave absorbers for anechoic chamber are needed to broaden the useful frequency bandwidth, reduce the thickness, and decrease the weight. There are various absorbers proposed for the above conditions, but they could not decisively solve the above requirements. The Electromagnetic wave absorber made by a conventional ferrite tile has, for example, broadened the useful frequency bandwidth by the way of forming air layer. Therefore, an air layer is formed absorber between a reflection plate and a sintered Ni-Zn ferrite tile of 7 mm in thickness, which has reflectivity less than -20 dB from 30 MHz to 450 MHz in frequency band, far narrower than the aimed bandwidth. The purpose of this paper is on the development of a universal anechoic chamber for measuring radiated electromagnetic wave or immunity of electronic equipments, GTEM-cell, wall material for prevention of TV ghost, etc. Accordingly, in this paper, a broadened electromagnetic wave absorber is designed, which has the reflection characteristics less than -20 dB from 30 MHz to 5,430 or 8,000 MHz in the bandwidth. Then we will design a super broadband electromagnetic wave absorber by inserting square Ferrite Cylinders Type with the thickness less than 23.5 m in three-layed type and with the frequency band from 30 MHz to 5,430-8,000 MHz under the above tolerance limits.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.11-15
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• 2004

This paper deals with EMC filter for a personal computer( PC). A PC contains many sources of noise inside and out, with many connected cables. High noise levels are also emitted from the PC became of high-speed signals. So radiated noise from the computer body may sometimes cause problems. Therefore, we design and fabricate an electromagnetic compatibility (EMC) filter for PC, which is composed of feed-through capacitors and ferrite beads with high permeability. Through extensive test, the proposed EMC filter is shown to have excellent differential-mode and common-mode noises filtering characteristics above 30 dB in the frequency band from 10 MHz to 1.5 GHz. The immunity characteristics are improved more than 10 to 30 dB over the frequency band from DC to 1.8 GHz

• Journal of the Korean Institute of Navigation
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• v.23 no.1
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• pp.23-28
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• 1999

With a rapid progress in electronic industry we enjoy various conveniences of life. As many kinds of information equipments are supplied even to most of individuals as to be called an information society, we are exchanging much information with one another surprisingly. Consequently the occupation density of microwave frequency band is highly increased, and electromagnetic environment is getting more seriously bad. It often gives fatal blow to even human life and thus becomes serious social problems. Electromagnetic wave absorbers for anechoic chamber are needed to broaden the effective frequency bandwidth, reduce the thickness, and decrease the weight. There are various absorbers proposed for the above conditions, but they could not decisively solve it the alone requirements. The Electromagnetic wave absorber made by a conventional ferrite tile has, for example, broadened the useful frequency bandwidth by the way of forming air layer(practically use urethane foam, etc.) on the ferrite tile. Therefore, an air layer is formed between a reflection plate and a sintered Ni-Zn ferrite tile of 7 mm in thickness, which has reflectivity less than -20 dB from 30 MHz to 400 MHz in bandwidth. Accordingly, in this paper, a broadened electromagnetic wave absorber are designed, which has the reflection characteristics less than -20 dB from 30 MHz to 6,000 MHz in the bandwidth. Then we achieved the goal by design the inserting square Ferrite Cylinders with the thickness less than 17.5 mm on existing grid type Ferrite absorber. The purpose of this research is on the development of very wide-band electromagnetic absorber for a universal anechoic chamber for measuring radiated electromagnetic wave or immunity of electronic equipments, GTEM-cell, wall material for preventing TV ghost, etc.