• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.715-716
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• 2006

Nowadays, research of EMI/EMC is very important in electromagnetic wave surroundings generated from many electric and electronic devices. Especially, analysis of electromagnetic radiation characteristic and field have to be performed first of all. At the present most of EMI/EMC problems are solved by the method of practice and inspiration. Hence in this paper, will provide the first step for solving EMI/EMC problems in design process. Model of analysis is structure composed of PCB and Frame. By the first step, theory of dipole antenna is adapted to analyze electromagnetic radiation characteristic and field. Because it is fundamental of analysis of electromagnetic radiation. And it will be expanded for structure of PCB and Frame. Finally, it provide the basic method of analysis of electromagnetic radiation characteristic and field by making similar dipole antenna to PCB and Frame structure.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.527-531
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• 2010

The optimized sheet for EMI shielding was prepared by metal power with Fe series. Then various metal powders were deposited on the sheet by PVD method. Moreover, the PVdF nanofiber membrane was used to compare the characteristic of EMI shielding efficiency of various metal powders. The electrical property was measured by the 4-point probe method. The result from EDS confirmed that the metal powder existed on the sheet. EMI shielding efficiency was analysed by EMI shielding measurement apparatus. The lowest electrical resistance, $641.95{\Omega}{wcdot}cm$, was obtained with $1000\;{\AA}$ deposition of Cu on the sheet. It was revealed that the EMI shielding efficiency increased with increase of the metal deposition thickness. The sheet deposited by Cu with $1000\;{\AA}$ showed the highest EMI shielding efficiency, 32.5 dB.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.3
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• pp.232-242
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• 1990

This paper presents the formulas for load currents of a cascaded transmission line excited by external plane wave using Smith's method for EMI currents of a single transmission line. Calculating under the condition that the lines having same characteristic impedence are cascaded, numerical results of this study are well agreed with those of Smith and show the fact that as the width and length of the line reduced to 1/10 respectively, the load-EMI currents decreased by about 40dB.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.2
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• pp.137-143
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• 2015

This paper presents the intra capacitance modeling based on the winding method and section bobbin for CM choke capable of EMI attenuation of broad bands from lower to higher frequency bands and high frequency type common-mode choke capable of EMI attenuation of high frequency band used in the EMI Block of LED-TV SMPS. The case of high frequency type CM choke can be explained by the parasitic capacitance of three types of CM choke. The winding method of section bobbin type is smaller than the others. The first resonant frequency of the proposed CM choke tends to increase as the parasitic capacitance becomes small and its impedance characteristics improved performance as the first resonant frequency increases. The CM chokes of the proposed section bobbin type shows that in the future, the method may have practical use in LED/LCD-TV SMPS and in several applications, such as LED lighting, adapters, and so on.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.12
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• pp.277-284
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• 2012

In this paper, we analyzed various noise in the video stream system that have largely influence on EMI noise. We presented the remedy for these various noises and then designed the wireless video streaming system for a vehicle. To minimize EMI noise, we derived the improvement of noise characteristic from impedance matching, new design of the inner layer of the PCB line design and new design of high-speed data Interfaces. As a result, the final system showed 40[dBuV/m] and 47[dBuV/m] dB in the each regulation band.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.3
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• pp.48-58
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• 1994

In this paper, a CLPDA (Crossed Log-Periodic Dipole Antenna) for EMI / EMC Measurement is presented, and is analyzed by Combining the moment method and the transmission line theory. The CLPDA has a broaddband characteristic. It is so important to achieve a impedance matching over op- erating frequency range that Twin-boom method is used at feed point. Here, the current distribution, input admittance, radiation pattern and gain are calculated. In practice CLPDA is fabricated. Calculated result for radiation pattern and gain are very closed to measured result.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.2
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• pp.84-89
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• 2007

MIL-STD-461E, EMI military standard for the equipment and subsystems, requires reception characteristic tests to verify the susceptibility of a receiver against the jntermodulation and spurious signals. Because the CS103 and CS104 of MIL-STD-461E show the test configuration of the equipment unit like a traditional receiver, it is possible to verify the susceptibility only for the reception signal through analog filters. However, at present when software programming techniques make a progress, the CS103 and CS104 tests need to evaluate the reception signal of the subsystem which includes both the digital filtering effects and analog filter characteristics. These test and evaluation techniques applied to a surveillance radar subsystem. This paper researched the EMI test methods in order to confirm feasibility of these test and evaluation techniques. Also the test results are compared and analyzed.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.212-215
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• 1995

In this paper, The characteristic of Harmonic spectrum is studied for generally used three-phase diode rectifier. and filter design criteria is showen in the sense of THD, DPF, and PF. As the becoming of Automative and informative era, the demand of critical and stable control becomes more and more important. But much EMI emissions are generated for more critical and stable control in power electronic system these EMI emissions can be measured using LISN(Line Impedance Stabilization Network). So we are to investigate the behavior of Conducted EMI emission in Diode Rectifiers using LISN in frequency domain.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.389-395
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• 2016

The evolution of electro-mechanical impedance (EMI) of the piezoelectricity (PZT) sensor was investigated to determine the setting times of cementitious materials in this study. The PZT sensor coated with non-conductive acrylic resin was embedded in cement paste before casting and the EMI signatures were continuously measured. Vicat needle test and semi-adiabatic calorimetry test were also conducted to justify the validity of EMI senssing technique in setting monitoring of cementitious materials. The results show that significant changes in EMI resonant peak magnitude and frequency during setting process were observed, and that the setting times determined by EMI sensing technique were relevant to the setting times measured by Vicat needle test and semi-adiabatic calorimetry test.

• Korean Journal of Materials Research
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• v.17 no.5
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• pp.239-243
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• 2007

The evaluation and comparison have been made for the EMI noise which was included in the signal from the sensors in the acoustic emission testing for the bottom plate of ground tank at full. The EMI signal has been classified into two types. One is the signal with very short AE count, and this signal possibly can be filtered by front end filter setting of the channel count with low level of 4 and high level of $10^8$. The other EMI signal occurred from CH 1, CH 3 and CH 10, and had high and constant duration with high energy and count (maximun duration > $10^5\;{\mu}s$), and has characteristic gradient of accumulation amplitude distribution. This signal should be removed in the AE signal evaluation by filtering, because this may affect to the total gradient.