• Journal of information and communication convergence engineering
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• 제15권4호
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• pp.237-243
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• 2017

This paper presents an analysis of the electromagnetic interference of a heterogeneous power bus where electromagnetic bandgap (EBG) cells are irregularly arranged. To mitigate electrical-noise coupling between high-speed circuits, the EBG structure is placed between parallel plate waveguide (PPW)-based power buses on which the noise source and victim circuits are mounted. We examine a noise suppression characteristic of the heterogeneous power bus in terms of scattering parameters. The characteristics of the dispersion and scattering parameters are compared in the sensitivity analysis of the EBG structure. Electric field distributions at significant frequencies are thoroughly examined using electromagnetic simulation based on a finite element method (FEM). The noise suppression characteristics of the heterogeneous power bus are demonstrated experimentally. The heterogeneous power bus achieves significant reduction of electrical-noise coupling compared to the homogeneous power buses that are adopted in conventional high-speed circuit design. In addition, the measurements show good agreement with the FEM simulation results.

• ETRI Journal
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• 제31권2호
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• pp.201-208
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• 2009

This paper proposes a spiral-shaped power island structure that can effectively suppress simultaneous switching noise (SSN) when the power plane drives high-speed integrated circuits in a small area. In addition, a new technique is presented which greatly improves the resonance peaks in a stopband by utilizing ${\lambda}$/4 open stubs on a conventional periodic electromagnetic bandgap (EBG) power plane. Both proposed structures are simulated numerically and experimentally verified using commercially available 3D electromagnetic field simulation software. The results demonstrate that they achieve better SSN suppression performance than conventional periodic EBG structures.

• ETRI Journal
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• 제41권6호
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• pp.731-738
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• 2019

We proposed a novel electromagnetic band-gap (EBG) cell-embedded antenna structure for reducing the interference that radiates at the antenna edge in wireless access in vehicular environment (WAVE) communication systems for vehicle-to-everything communications. To suppress the radiation of surface waves from the ground plane and vehicle, EBG cells were inserted between micropatch arrays. A simulation was also performed to determine the optimum EBG cell structure located above the ground plane in a conformal linear microstrip patch array antenna. The characteristics such as return loss, peak gain, and radiation patterns obtained using the fabricated EBG cell-embedded antenna were superior to those obtained without the EBG cells. A return loss of 35.14 dB, peak gain of 10.15 dBi at 80°, and improvement of 2.037 dB max at the field of view in the radiation beam patterns were obtained using the proposed WAVE antenna.

• 한국전자통신학회논문지
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• 제10권1호
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• pp.27-32
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• 2015

본 논문에서는 GNSS(Global-Navigation Satellite Service)에서 사용되는 단말기의 PCB(Printed Circuit Board) 전원안정화를 위해서 PCB 내층에 삽입될 EBG(Electromagnetic Band Gap) 구조체를 제안한다. 버섯모양의 제안된 EBG 구조체를 통한 PCB에서의 관심 금지대역폭/저지대역폭 주파수는 GNSS와 이동통신 관련 주파수를 포함하는 1.55GHz에서 1.81GHz이었으며, 시뮬레이션 결과, 이 구간에서 삽입손실(S21)이 약 -40dB 이하로 형성됨을 볼 수 있었다. 본 연구결과는 향후, PCB 회로 설계의 PDN(Power Delivery Network)구조의 안정화 향상 및 EMI(Electro Magnetic Interference) 대책에 효과적 대응이 유용할 것으로 기대된다.

• 한국전자파학회논문지
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• 제27권10호
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• pp.945-948
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• 2016

최근 프리미엄급 스마트폰들은 대부분 메탈 프레임을 채용하고 있으며, 이는 중저가 스마트폰으로 확산되고 있는 추세이다. 하지만, 메탈 프레임은 스마트폰 내 디지털 부품에서 발생하는 전자파 노이즈의 좋은 전달 경로가 되어, 스마트폰 상단부 또는 하단부에 위치한 무선 안테나에 전자파 간섭을 일으키는 원인이 될 수 있다. 본 논문에서는 메탈 프레임에 EBG(Electromagnetic Band Gap) 구조를 적용하여 안테나로의 전자파 간섭을 줄일 수 있는 방법을 제안하였다. $7{\times}6$ 배열의 다중 비아(Multi-via) EBG 구조를 갖는 메탈 프레임을 설계하였으며, 이를 적용할 경우, 메탈 프레임을 통한 표면 전자파 노이즈 간섭을 20 dB 정도 저감시킬 수 있음을 시뮬레이션을 통해 확인하였다.

• 한국ITS학회 논문지
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• 제16권1호
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• pp.176-185
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• 2017

본 논문은 지능형교통시스템(ITS: Intelligent Transport System)을 위한 V2X 간의 무선통신시스템에 적용되는 WAVE(Wireless Access in Vehicle Environments) 안테나 시스템에 대한 연구이다. 5.825~5.9GHz 주파수대역의 WAVE 통신은 차량이 주행하면서 도로 인프라에 설치되어 있는 기지국과 다른 차량에 장착되어 있는 단말기간의 무선통신에 사용할 수 있도록 하는 표준화된 프로토콜이다. 최근의 WAVE 통신시스템 연구에서는 통신거리에 따른 통신성능을 향상시키기 위해서 기지국과 차량 단말기 기술개발 위주로 연구되고 있으나, 본 논문에서는 시스템 성능 개선 가능성을 검토하고자 차량 루프에 장착가능한 자동차용 안테나 시스템의 설계구조 개선에 대한 연구를 진행하였다. WAVE 안테나 베이스 구조에 EBG(Electro Band-Gap) 구조를 적용하여 비교시뮬레이션을 통해 반사손실이 저감되어 성능이 향상되는 것을 확인하였다.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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• pp.138-140
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• 2009

This paper investigates a method to remove the undesirable resonance of the rectangular power-bus structure(PBS) using an inductive layer. The equivalent surface impedance of the proposed loading is calculated for characterizing the proposed EBG geometry. The effects of the strips and the immediate surroundings are illustrated by a number of numerical experiments.

• Journal of electromagnetic engineering and science
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• 제14권4호
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• pp.346-348
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• 2014

A dispersion analysis is performed to estimate the stopband characteristics of electromagnetic bandgap (EBG) structures with defected ground structures (DGS) of various shapes. Design guidelines are suggested for both elliptical and rectangular DGS patterns that result in a maximum stopband bandwidth for a given perforation area. This method provides a basis for numerical optimization techniques that can be used in synthesizing DGS shapes to meet bandgap requirements and layout constraints.

• 한국식생활문화학회지
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• 제34권4호
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• pp.378-388
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• 2019

This study aimed to assess the nutritional quality of breakfast among Korean school-aged children and adolescents depending on eating together as a family, based on the 2013-2014 Korea National Health and Nutrition Survey. One day 24-hour recall data of 1,831 children and adolescents aged from 6 to 17 years were collected. The nutritional quality of breakfast was analyzed and compared between Family Breakfast Group (FBG, n=1,410) and Eating-alone Breakfast Group (EBG, n=421). The results showed that age, family structure, number of family members, and frequency of breakfast were associated with eating breakfast as a family. The calorie intake from breakfast explained 19% and 16% of the daily intake for FBG and EBG, respectively. The percentages of children and adolescents consuming Vitamin A, Vitamin $B_1$, Vitamin $B_2$, Vitamin C, Niacin, and Iron less than 1/4 of the Estimated Average Requirements were significantly lower in FBG than in EBG. The average numbers of serving for "Grains" and "Vegetables" food groups and the average Dietary Diversity Score were significantly higher in FBG than in EBG. Overall, the results indicated that eating breakfast as a family is positively associated with nutritional quality of breakfast among Korean school-aged children and adolescents.

• 한국군사과학기술학회지
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• 제17권4호
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• pp.485-491
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• 2014

An Antenna & RF system for a fly-away satcom terminal application on ka-band is presented in this paper. The Fly-away satellite terminal can be moved and operated by two person and adapt automatic satellite tracking system in order to decrease the tracking time. Additionally, for low-power consumption, compact size and light-weight, a dual reflector antenna is constructed using dual-offset gregorian antenna structure. For minimize weight, the reflector of the antenna is made of Magnesium. For low-power consumption and light-weight, the pHEMT MMIC compound devices is utilized. The Electronic Band-Gap(EBG) Low-Pass Filter(LPF) is designed for harmonic rejection. In the receiving part, Low-Noise Block converter(LNB) structure is designed for compact and lightweight. In this paper, fly-away satcom terminal with low-power consumption, compact size and light-weight is described with antenna system and RF system performances. Through the experimentation, fly-away terminal's EIRP is more than 50dBW, G/T is more than $17dB/^{\circ}K$.