• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 추계학술대회
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• pp.63-65
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• 2011

현재 범용성이 높은 전자계 시뮬레이터가 널리 보급되어 왔으며, 안테나 설계, EMC 설계, 측정, 초고주파 소자 설계 등에 활용되고 있다. 본 연구에서는 X 밴드 영역에서 다양한 전자계 문제 해석을 목적으로 멀티 코어 기반 PC 자원을 보다 효율적으로 활용하고, 나아가 TCP/IP 기반 네트워크 토폴로지 구성을 통한 효율성 높은 전자계 시뮬레이터 구현을 위한 프레임워크 구축과 구현 방안을 제안한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.743-748
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• 2007

This paper describes a lens transmissive type tilting actuator for a projection TV. An electromagnetic analysis and a structural analysis of the tilting actuator system is necessary to design a tilting actuator for a projection TV. The tilting actuator is composed a permanent magnet, coil and yoke as the electromagnetic components and it needs a driving hinge part as the mechanical component. The design of the tilting actuator for the projection TV is performed by the following procedure. Firstly, a magnetic flux density of the tilting actuator system is analyzed by a mathematical theory and an electromagnetic FEM. Secondary, a magnetic circuit method is used to determine tilting force. Thirdly, the structural FEM is carried out with an FE model of a lens-transmissive type tilting actuator and then the prototype of the model is manufactured. The characteristic of the prototype is experimentally observed. Finally, a design for a new hinge configuration is suggested for better performance.

• 한국전기전자재료학회논문지
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• 제23권11호
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• pp.906-910
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• 2010

This paper describes the design and analysis of vibration driven cylindric electromagnetic energy harvester. The proposed harvester consists with spring, coil and rear earth magnet. The design utilizes an electromagnetic transducer and its operating principle is based on the relative movement of a magnet pole with respect to a coil. In order to optimal design and analysis, ANSYS FEA (Finite Elements Analysis) and Matlab model were used to predict the magnetic filed density with vibration and the generated maximum output power with load resistance. The system was designed for 6 Hz of natural frequency and spring constant was 39.48 N/m between 2 mm and 6 mm of displacement in moving magnet. When moving magnet of system was oscillated, each model was obtained that induced voltage in the coil was generated 2.275 Vpp, 2.334 Vpp and 2.384 Vpp, respectively. Then maximum output powers of system at load resistance ($1303{\Omega}$) were generated $124.2{\sim}132.2\;{\mu}W$ during magnets input displacement of 3 mm and 6 Hz periodic oscillation.

• 전기전자학회논문지
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• 제21권3호
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• pp.272-275
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• 2017

최근 반도체의 집적도가 증가하고 배선 폭이 미세해짐에 따라 칩 수준의 EMI(electromagnetic interference)가 문제로 대두되고 있다. 이에 따라 칩 제조사는 칩 수준의 EMI를 측정하기 위해 TEM 셀(transverse electromagnetic cell)을 사용하고 있다. 이를 위해 측정용 PCB(printed circuit board)를 제작하여야 하지만, PCB의 배선 패턴 등이 EMI 측정에 영향을 미칠 수 있다는 점이 간과되고 있다. 본 논문에서는 PCB 설계 변수를 변화시켜가며 테스트 패턴을 제작한 다음 TEM 셀의 EMI 측정에 미치는 영향을 분석하였다. 또한 이를 바탕으로 EMI 측정에 미치는 영향을 최소화하기 위한 PCB 설계 가이드라인을 제시하였다.

• 한국전자파학회논문지
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• 제12권1호
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• pp.50-57
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• 2001

본 논문에서는 광대역 특성을 가지는 원편과 마이크로스트립 EMC 크로스 다이폴 어레이 안테나의 설계에 관하여 기술하고 있다. 광대역 특성과 원편과 특성을 실현하기 위해, 급전선과 전자기적으로 결합하는 크로스다이폴 소자를 제안한다. 원편파 EMC 크로스 다이폴 소자의 최적 설계 파라미터들은 FDTD와 앙상블에 의해 계산되었다. 어레이에 있어서 전계의 균일한 개구분포를 얻기 위하여, 크로스 다이폴 소자들을 마이크로스트립 급전선로를 중심으로 하여 지그재그로 배치하는 Offset 기법을 사용하였다. 20소자 어레이 설계로부터 12 GHz에서 계산된 축비와 이득은 각각 0.1 dB와 9.9 dBi 였다. 제작된 20소자 어레이 안테나의 주파수 특성이 측정되었고 계산 결과와 잘 일치하였다.

• ETRI Journal
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• 제40권4호
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• pp.546-553
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• 2018

Since the Gyeongju earthquakes in 2016, there have been increased research interests in the areas of seismic design, building collapse, and rescue radar applications in Korea. Ground penetrating radar (GPR) is a nondestructive electromagnetic method that is used for underground surveys. To properly design ground penetrating radar that detects buried victims precisely, it is important to study electromagnetic wave propagation channel characteristics in advance. This work presents an electromagnetic propagation environment analysis of a trapped victim for GPR applications. In this study, we develop a realistic collapse model composed of layered reinforced concrete and a victim positioned horizontally. In addition, the effects of rebars and the distance between the radar antenna and target are investigated. The numerical analysis presents the electromagnetic wave propagation characteristics, including amplitude loss and phase difference, in the 450-MHz and 1,500-MHz frequency band, and it shows the electric field distribution in the environment.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1998년도 추계종합학술대회
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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.

• 한국정보통신학회논문지
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• 제3권1호
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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.

• 한국자기학회지
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• 제26권2호
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• pp.55-61
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• 2016

본 논문에서는 설계변수 변화에 따른 특성을 빠른 시간 내에 파악할 수 있는 등가자기회로법(equivalent magnetic circuit method)을 활용하여 콜레노이드(colenoid) 타입의 선형 액츄에이터 설계 알고리즘을 제시하였다. 우선 선형 액츄에이터의 중요치수가 결정되면 등가자기회로법에 의해 슬롯 폭 비율 및 인가전류에 따른 클램핑력으로 파라미터 맵(parameter map)을 완성하고 이를 활용하여 효율적인 슬롯 폭 비율을 결정하였다. 또한 최대 클램핑력(clamping force)을 얻기 위해 극 폭 조절 알고리즘을 수행하여 최적의 극 폭 치수를 선정하였으며 이를 바탕으로 인가전류에 따른 클램핑력을 계산하여 40 kN 이상 출력하기 위한 최적의 극 수, 극 폭 치수 및 인가전류를 결정하였다. 제안된 설계 알고리즘은 최적설계 방법인 반응표면법(response surface method)과 비교하여 제안한 설계 알고리즘의 타당성을 검증하였다.

• International Journal of Contents
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• 제7권4호
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• pp.50-55
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• 2011

To achieve efficient field formulations and fast numerical computations, the reciprocal relations and equivalence between tangential and normal boundary conditions for electromagnetic fields are discussed in terms of the Maxwell's differential equations. Using the equivalence of each boundary condition, we propose the six essential boundary conditions, which may be applicable to matching electromagnetic discontinuities to efficiently design RF devices. In order to verify our approach, the reflection characteristics of a rectangular waveguide step are compared with respect to six essential boundary conditions.