• 한국통신학회논문지
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• 제22권7호
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• pp.1403-1410
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• 1997

Because streaming mode connection server suitable to wide area ATM networks performs transmission, reception and lookup with time restriction for the transmission time of a cell, it has demerits of large cell loss incase that burst traffic occurs. Therefore, in this paper to decrease cell loss we propose a high speed CAM (Content Addressable Memory) which is capable of processing data of streaming mode connections server at a high speed. the proposed CAM is applied to forwarding table VPC map which performs function to output connection numbers about input VPI(Virtual Path Identifier)/VCI(Virtual Channel Identifier). The designed high speed CAM consist of DBL(Dual Bit Line) CAM structure performed independently write operation and match operation and two-port SRAM structure. Also, its simulation verification and full-custom layout is performed by Hspice and Composs tools in 0.8 .$\mu$m design rule.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1997년도 전력전자학술대회 논문집
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• pp.211-215
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• 1997

Localized communication networks for office automation, security monitoring, environmental management of buildings, computer communications, and other applications enjoy every increasing demand. This paper proposes a direct sequence spread spectrum communication system for use in power line data transmission. Advantages of power distribution circuits include reasonably universal coverage and easy access vis a standard wall plug. Disadvantages include limited communication bandwidth, relatively high noise levels, and varying levels of impedance, noise, and attenuation. Spread spectrum signalling provides immunity to narrow-band signal impairments and multiplexing capability. Our prototype power line communication module supports completely physical and data link layers based on the international standard ISO 10368 for reliable high-speed power line communication system. Moreover it provides useful functions to compose a plant monitoring and control system. All the circuits of the communication module are included in one compact circuit. Thus a functional communication system for the power line plant monitoring and control is implemented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.3121-3123
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• 2000

Power line communications is a topic which has been studied for many years, However. the technology has not been widely adopted for data networking in homes and small businesses due to low speed. low functionality. and other barriers. Recently. with a proper technology. it is shown that the power line infrastructure can also be served as a high-speed communications medium. This paper describes a transmission scheme for power lines that is based on orthogonal frequency division multiplex(OFDM) technique. This technique can be used for high-speed data communication over the power line. This paper also presents an adaptive tracking algorithm which allocate bits and power adaptively according to the channel characteristics. The performance of the proposed scheme has been demonstrated by some simulations with taking modeled channel conditions into account.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.757-766
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• 2005

A speed of a train is controlled by Automatic Train Control system and the continuous transmission system provide the speed related information in the Korean High Speed Line. The primary objective of this paper is to measure the level of continuous signal and to calculate the message of that signal. A measuring equipment is introduced and the equipment provide the base line of the level of current and the correction information of the message.

• 한국전자통신학회논문지
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• 제9권10호
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• pp.1197-1205
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• 2014

최근 초고화질(4K-UHD) 영상 시스템의 신호전송은 비압축 고속 데이터로 전송되며 고속 신호의 인터페이스 구간에 서로 다른 케이블 사이에서 나타나는 EMI, 스큐(skew) 문제로 인하여 영상신호의 왜곡, 지터 등으로 시스템 구현에 한계가 있다. 이와 같이 비압축 고속 데이터를 고속전송하기 위하여 V-by-One HS 인터페이스 기법을 적용하여 본 논문에서는 고속 영상신호에 대하여 HSD(High Speed Differential) 전송선로의 신호무결성을 분석하였다. UHD 영상패턴 제어 인터페이스의 PCB 설계 방법을 RF 전송기법으로 적용하였으며 구현된 4K-UHD급 영상패턴 제어 신호발생기의 V-by-One HS 영상신호를 측정한 결과, 전송품질이 고속전송신호규격에 만족함을 보였다.

• 전자공학회논문지A
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• 제33A권2호
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• pp.69-77
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• 1996

We analyzed wideband propagation characteristics of a microstrip transmission line based on FR-4 composite substrate using the wideband complex dielectric constant model and the phenomenological loss equivalence method. The loss calculated by constant relative permittivity and loss tangent is greatly overestimatd compared to that calculated by the frequency-dependent complex relative permittivity. This wideband analysis can be helpful to characterize high-speed and high-density transmission lines associated with the wideband dielectric characteristics and shows that the FR-4 composite substrate has high potential of high frequency circuit applications in terms o fthe propagation loss.

• 한국멀티미디어학회지
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• 제1권1호
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• pp.19-32
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• 1997

There are many kinds of predominant modes to transfer Multimedia information on internet in the world. Various methods are applied to get real time multimedia data as possible as we need. At the moment it is very difficult to use acceptable technologies for performe those methods effectively on the Networks. This paper gives the alternative directions and trends for research and development of multimedia transmission on the internet. ATM is one of the best mode to transfer mass-multimedia data at the high speed on the Broad-Band ISDN until now. And xDSL (xDigital Subscriber Line) is an excellent typical method on the PSTN (Public Switched Telephone Network) using old type telephone line. But they are not yet applied into the phase of practical use together this time. So this paper analyzes what we need and how to develop the multimedia transmission modes which we can send on the internet without a problem or any difficulty for our various multimedia information all the time under low cost and high speed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.466-469
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• 2008

As the industry develops, they are interested in the fault of electric machines and the effect on human beings by electromagnetic fields and waves which generate through much use of electric machines and appliances. In foreign country, they confirmed the standard about electromagnetic interference and compatibility(EMI/EMC) of electromagnetic fields and waves generating electricity transmission/distribution equipments and electric appliance. In Korea, such criteria are applied too. Before EMI/EMC standard is applied, it is important to prepare the plan to predict and reduce electromagnetic fields and waves which generate in the inner and the outer part of electric machinery. To solve such a problem, they calculated Maxwell's equations by finite element method(FEM) and finite difference method(FDM) in most papers. However, these methods have the disadvantage that mathematical expansions are complex and need much memory allocations for grid and mesh generations. In this paper, we introduce transmission line matrix(TLM) method that media of which trains consists are regarded as transmission lines for electromagnetic field calculation in Korean High Speed Train, calculate the electric and magnetic field, and analyze the results.

• 전자공학회논문지S
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• 제36S권11호
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• pp.9-14
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• 1999

본 논문은 10Gbps 광 전송 장치의 저속부와 고속부 셀프 간에 77.76Mbps의 10라인의 전송 방법인 H-BUS 방식보다 효율적인 622Mbps 의 1라인으로 전송하기 위하여 622Mbps로 수신되는 데이터를 동기식 디지털 계위(SDH)에 정의된 동기식 전달방식(STM)-64 프레임 형태로 정렬할 수 있는 리프레임 방법을 설명하였으며 이를 VHDL로 설계하여 10Gbps 광 전송 장치의 T14U 보드의 10G-S4 ASIC내에 적용하였다.

• 한국정보통신학회논문지
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• 제19권7호
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• pp.1639-1645
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• 2015

UHD 고속영상 전송 시스템에서 EMI 특성은 특정 주파수 대역의 신호가 전기적, 구조적으로 주파수가 일치될 때, 에너지가 집중되고 신호의 흐름을 방해하여 왜곡이 발생하므로 시스템이 불안정해지는 원인이 된다. 이러한 신호의 왜곡을 제거하기 위하여 전원 무결성 분석과 EMI 현상에 대한 고주파 설계기법이 요구되어진다. 따라서 본 논문에서는 다층인쇄회로기판(MLB : Multi-Layer Printed Circuit Board) 구조에서 발생하는 고주파 잡음을 최소화하고 신호 무결성과 전원 무결성을 개선하면서 EMI를 억제하는 최적의 MLB 설계방법을 제안한다. 제안한 MLB의 특성 임피던스 파라미터는 비유전율 ε_r = 4.3, 고속영상 차동신호(HSVDS : High-Speed Vih = 0.145deo Differential Signaling)의 선로 폭 w = 0.203, 패턴의 간격 d = 0.203, 패턴의 두께 t = 0.0175, 베타층 위의 높이 를 고려하여 특성 임피던스 Zdiff = 100.186Ω으로 설계하였다. 실험결과 아이패턴의 출력 크기가 672mV, 지터는 6.593ps, 전송 주파수가 1.322GHz, 신호 대 잡음비는 29.62dB로 전송 품질이 개선 전보다 약 10dB 향상 되었다.