• 한국인터넷방송통신학회논문지
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• 제12권1호
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• pp.217-223
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• 2012

다양한 산업 분야와 일상생활에서 시각동기 문제는 매우 중요하다. 일상생활에서 사용하는 전자제품 중에서 보다 정확한 시각정보를 활용 한다면 좀 더 정확한 동작을 수행하게 할 수 있다. 전력선을 통해 전원을 공급받아 동작하는 제품의 경우, 전력선을 통해 정확한 시각 정보를 전송 받을 수 있다면 시각동기 문제를 좀더 쉽게 해결할 수 있다. 본 논문에서는 GPS위성으로부터 수신한 시각정보를 전력선을 통해서 각 단말에 전송하는 전력선 방송 시스템을 개발하였다. 또한 시각 소스를 GPS에 동기된 스마트폰을 이용할 수 있도록 하였으며, 전력선 모뎀 기술이 갖는 장거리 전송의 어려움을 해결하기 위한 중계 방식을 제안하고 중계 시스템을 구현하였다. 본 논문에서 개발된 시스템은 시각 정보의 전송 거리를 확장하여 광역 PLB(Power Line Broadcasting) 시각방송을 구현하였다. 또한 본 논문에서는 중계 시스템의 성능을 평가하여 그 유용성을 확인하였다.

• 한국전자통신학회논문지
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• 제5권2호
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• pp.171-179
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• 2010

일반적으로 송전용 전력선 및 절연체의 감시 및 유지 보수를 위한 한 방법으로서 유인 헬기를 이용하여 가시영상 및 적외선 열영상을 측정하고 이를 분석하는 방법이 이용되고 있다. 이러한 감시 및 유지보수 방법을 무인화하기 위해 항공 영상으로부터 전력선의 자동 추출에 대한 연구가 진행 되어 왔다. 본 논문에서는 열영상 기반의 전력선 영상에서 전력선을 효과적으로 검출하기 위해 Hough변환 및 전력선의 방향성을 이용하는 방법을 제안하고자 한다. 제안된 방법은 얻어진 에지성분을 바탕으로 하프변환을 하고 방향성분을 분석하여 전력선의 분포특성을 얻고 이를 이용하여 전력선을 검출한다. 특히 얻어진 항공영상에서 전력선이 평행한 경우와 원근법에 의해 평행하지 않은 경우 모두 양호한 검출특성을 보인다. 모의실험을 통하여 이러한 전력선 검출 방법은 배경 영상의 복잡성과 항공영상의 전력선 방향에 무관하게 유효한 방법임을 확인할 수 있었다.

• 센서학회지
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• 제23권5호
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• pp.349-355
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• 2014

In this paper, we developed a new method to transmit multiple visible light channels in time division mode using the AC power line frequency in order to prevent the crosstalk between adjacent optical signals. Synchronizing pulses are generated from the 220 V power line, and one pulse period is subdivided into several time slots for visible light channels. Each channel transmits data in a predefined time slot without interfering adjacent channels. In experiments, synchronizing pulses with a repetition rate of 240 Hz were generated from the 60 Hz power line, and three VLC channels with a bit rate of 9.6 kbps transmitted data independently using the time slots between synchronizing pulses. This configuration is very useful in constructing time division VLC networks for multiple sensors.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.116-119
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• 2004

The existing monitoring and control systems of utility-pipe conduit (power tunnel, cable tunnel etc) have established communication lines using optical fiber, leaky coaxial cable (LCX), and several kinds of control cable. Due to the properties of the used media, the cost of equipment is considerably high and the maintenance of the system is difficult. Also, the term of carrying out is long so that the extension of the system is in difficulty. Now it is desirable to adopt Power Line Communication (hereinafter, PLC) technology in the monitoring and control systems and use the existing low-voltage power-line for lamplight as communication line. This will lead the reduction of the construction cost and the easy maintenance of the system. In this paper, we research the characteristics of PLC in conduit, design and manufacture the field test system, and analyze the performance of the system by field test. Then, we introduce the reliable monitoring and control system of utility-pipe conduit using PLC.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1956-1958
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• 2002

This paper reviews the calculation of induced voltage to a communication line from Power Transmission Line. Power lines, both overhead and underground, often run parallel to weak current lines, such as telecommunication, signal or data transmission systems or protection circuits. The coexistence of both systems in parallel over long lengths is accompanied by the possible induction of significant longitudinal voltage in the weak current line. In order to evaluate a precise induced voltage, this paper indicated problem about coefficient and numerical formula and present some induced voltage production technology standard application.

• Journal of Electrical Engineering and Technology
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• 제9권4호
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• pp.1394-1400
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• 2014

The current flowing through the overhead transmission lines causes induced voltage on the communication lines, which can be prevented by calculating the induced voltage at the planning stage for overhead transmission line installment through an agreement between the communication and electric power companies. The procedures to calculate the induced voltages, however, are complicated due to the variety of parameters and tower types of the overhead transmission lines. The difficulty necessitates the development of a simulator to measure the induced voltage on the communication lines. This paper presents two simulators developed for this purpose; one using the Data Base (DB) index method and the other using the Graphic User Interface (GUI) method. The simulators described in this paper have been implemented by the EMTP (Electromagnetic Transient Program).

• 산업기술연구
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• 제27권B호
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• pp.21-27
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• 2007

The power line channel has time-variant characteristics caused by various kind of electrical devices. This characteristics are synchronized with the main voltage by their own characteristics. The main factors of disturbance are the variation of the channel impedance and noises. In other papers, the synchronous noise modeling has been achieved. But the modeling is not satisfied simultaneously with the time domain and the frequency domain and there are not any discussion about short-term variations of the channel impedance which cause to the signal fading. Therefore, this paper researched to solve problems about the signal fading by analyzing the short-term variation of the channel impedance, and proposed the synchronous noise modeling which is satisfied simultaneously in the time domain and the frequency domain.

• 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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.480-481
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• 2009

In the paper we study for the ubiquitous networking based on power line communication technology with digital signal transmission. The necessity of research for using resources in the network effectively is being increase as network to use the PLC with smart grid networking. The data rate has compared with implemented modem 250Mbps in the pixel resolution and bandwidth, which has degraded with 80%. We also proposed for design of high-definition digital signal transceiver, which has used in the network between digital multimedia with PLC. Using resources in the network effectively can be also verified with this research.

• 한국위성정보통신학회논문지
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• 제12권2호
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• pp.46-50
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• 2017

본 논문에서는 전력선통신 시스템에서 인공지능 기반 스펙트럼 할당 기법을 제안한다. 송신 신호의 주파수 대역은 스펙트럼 할당 기법을 통해서 조정이 가능하고, 이를 통해 간섭을 피할 수 있다. 이에 따라 전력선 통신 시스템의 성능과 스펙트럼 효율이 향상된다. 시뮬레이션 결과를 통해 제안된 스펙트럼 할당 기법을 통해 스펙트럼 효율 향상과 통신 시스템의 성능이 향상된다는 것을 증명하였다.