• Title/Summary/Keyword: visible distance

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A Design and Development of the Smoke Detection System Using Infra-red Laser for Fire Detection in the Wide Space (광역 화재감지를 위한 적외선 레이저 연기 검출 시스템의 설계 및 구현)

  • Park, Jang-Sik;Song, Jong-Kwan;Yoon, Byung-Woo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.6
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    • pp.917-922
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    • 2013
  • In this paper, we propose a smoke detection system in order to detect a fire in a wide space, such as tunnel, airports using infra-red and visible laser. The proposed smoke detection system is composed of infra-red laser transmitter and receiver, visible laser and Zigbee wireless communication network. A visible laser is used to match transmitter and receiver and Zigbee network is utilized to propagate warnings of fire. If smoke is appeared between transmitter and receiver, received signals are decreased and it can be considered as occurring smoke. As IR laser transmitter and receiver are separated by long distance, it is difficult to match due to large variations caused by small change of direction. In this paper, it is proposed to match effectively using visible laser. When smoke is detected, warning informations are propagated by Zigbee network in the developed smoke detection system.

Experimental Demonstration of Long-reach 2×2 Multiple-Input Multiple-Output (MIMO) Visible Light Communications Using an Image Sensor Receiver (이미지 센서 수신부를 이용한 장거리 2×2 MIMO LED 무선 가시광 통신 실험)

  • Jeon, Jong-Bae;Kim, Sung-Man
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.8B
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    • pp.706-711
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    • 2012
  • The current visible light communication (VLC) systems have a short transmission distance and a low data rate. To overcome this, we studied on the method of appling MIMO technology to VLC. However, it is difficult to apply the original MIMO technology used in RF frequency to wireless VLC. In VLC system, a lens can be used to separate the transmitted signals. And, if we use an image sensor as the receiver, MIMO technology can be applied to LED wireless visible light communication. In this paper, we report an experiment of $2{\times}2$ LED wireless visible light communication using a commercial image sensor receiver. We show the experimental demonstration with a transmission length of 10.5 m and a data rate of 200 bit/s.

Design of Vehicle Safety Protocol on Visible Light Communication using LED (LED 가시광 통신을 이용한 자동차 안전 프로토콜 설계)

  • Kim, Ho-Jin;Kong, In-Yeup
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.563-565
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    • 2010
  • LED is low power and pro-environment semiconductor element. That can be used not only as the lighting function but also for Visible Light Communication(VLC). The VLC is the communication technology that can send data by blinking a fluorescent or LED using visible spectrum. That velocity of blinking can not be usually recognized by eyesight. Visible Light Communication using LED can be used in many fields. In the field of ITS(Intelligent Transportation System), Under construction on the road, Emitting traffic signs can be applied to transfer the vehicle information. In this paper, Emitting traffic signs in addition to the VLC give information about road condition, safety distance and the lane change. We design Communication protocol to provide safety service and verify protocol by experiment.

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Spectacle and "Keeping Distance from Spectacle" in Fashion (패션에 나타난 '스펙터클' 및 '스펙터클과 거리두기')

  • Park, Ju-Hee
    • Journal of the Korean Society of Costume
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    • v.59 no.5
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    • pp.83-100
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    • 2009
  • In the 'Society of the Spectacle', Guy Debord argued that modern life was dominated by the commodity form and the false desires it engendered. He predicted in 1967 that culture would become the driving force in the development of the economy by the end of the century, He was sure when culture becomes nothing more than a commodity, it must also become the star commodity of the spectacular society. Fashion, the starriest of star commodities with its seductive fantasy approaches to the viewers occluding the commercial reality. From this point, the spectacular property of the modern fashion can be found. This study starts on the notion that the modern fashion is on the center of capitalist consumer culture and is constructed by spectacle. On this premise, the purpose of this study is analysing the attribute of 'spectacle' and 'keeping distance £Tom spectacle' in modern fashion expressed in fashion show, fashion media and fashion store. The fashion houses in the 1990s that recognised the commercial value of shock and spectacle were eager to employ young spectacularly visible named designers. They generated the publicity necessary for sales of perfume, cosmetics, bags and diffusion range of clothes through the visible fashion show and fashion media. In the fashion show and fashion media, fashion goods as the commodity both flaunts and disguises its commercial nature in spectacle. The spectacle on the fashion store is the process turning the commodity into image to arouse viewer's higher interest. In the fashion store, the appearance of the commodity such as space, display, package is considered more importantly than its 'utility value'. Meanwhile, the study also covered the innovative trial to evade the ubiquitous 'spectacle' in fashion area.

Realization of Hybrid Localization System with Lighting LEDs and Ad-Hoc Wireless Network (LED 조명과 애드혹 무선 네트워크를 사용한 하이브리드 측위 시스템 구현)

  • Lee, Yong Up;Park, Joohyeon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37C no.9
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    • pp.774-783
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    • 2012
  • A simple, accurate, secure, long-lasting, and portable hybrid positioning system is proposed and designed in this paper. It consists of a lighting LED that generates visible light data corresponding to position information of a target and a Zigbee wireless network communication module with low power, security, and service area expansion characteristics. Under an indoor environment where there is 23.62m distance between an observer and the target, the presented hybrid positioning system is tested and is verified with the functions of Zigbee three hop wireless networking and visible light communication (VLC) scheme. The test results are analyzed and discussed.

Novel Gain Control Scheme of Efficient Signal Detection Technique for Multiple Access VLC Systems (다중 접속 가시광 통신을 위한 신호 검출 기법의 게인 조절)

  • Lee, Sun Yui;Kim, Jin Young
    • Journal of Satellite, Information and Communications
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    • v.11 no.1
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    • pp.32-36
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    • 2016
  • In this paper, a transceiver of VLC (Visible Light Communication) using LED white lighting has been implemented. We analyzed differences between conventional wireless communication and VLC with high-speed data transmission in a variety of environments, and confirmed symbols which passed through a channel using QAM. In order to get a high data rate, we found some variables that should be considered essentially though experiments. In addition, we set a bandwidth and found an optimal gain according to the distance between transmitter and receiver. We analyzed proposed system model through Labview and finally showed a system performance and to efficient data transmission and detection for VLC, we apply the orthogonal sequences to VLC system.

A study on the Frequency Modulation-based Audio Transmission System for Short-range Underwater Optical Wireless Communications (근거리 수중 광무선 통신을 위한 주파수 변조 기반 오디오 전송 시스템 연구)

  • Kim, Yeon-Joo;Sohn, Kyung-Rak
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.1
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    • pp.166-171
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    • 2012
  • In this paper, short-range underwater wireless communication technique using visible LEDs is proposed. As an alternative to conventional acoustic system, visible LED communications show high quality and high speed data transmission characteristics. We design a frequency modulation-based optical wireless audio transmission system. The CD4046B phase-locked loop device is applied to implement the frequency modulation and demodulation. With a transmission modulation of 100 kHz, audio signal has successfully received at a transmission distance of 30 cm.

Performance of CSK Scheme for V2I Visible Light Communication

  • Kim, Hyeon-Cheol;Kim, Byung Wook;Jung, Sung-Yoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.3
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    • pp.595-601
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    • 2015
  • These days, research related to Intelligent Transportation System (ITS) technology is being widely considered. ITS is inevitable for future transportation systems to reduce accidents, congestion, and offer a smooth flow of traffic. The use of Visible Light Communication (VLC) in ITS systems has been considered widely because of its EMC/EMI free and LED infrastructure reusable properties. Among the VLC schemes, this study analyzed the performance of the Color Shift Keying (CSK) scheme under a Vehicle-to-Infrastructure (V2I) downlink scenario to verify the capability of CSK as a communication tool for ITS. By modeling daylight noise using the modified Blackbody radiation model, this study examined the performance of V2I VLC under daytime conditions. The relationship between BER, the communication distance, and the amount of ambient-light noises under the pre-described V2I scenario were determined by simulations.

Color Clustered Multiple-input Multiple-output Visible Light Communication

  • Han, Phyu Phyu;Sewaiwar, Atul;Tiwari, Samart V.;Chung, Yeon-Ho
    • Journal of the Optical Society of Korea
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    • v.19 no.1
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    • pp.74-79
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    • 2015
  • A novel color clustered optical RGB multiple-input multiple-output (MIMO) system is presented. As visible light can be divided into three primary regions of red, green and blue, data can be modulated and transmitted separately using these three color clusters. Each color cluster comprised of 30 RGB LEDs is modulated using on-off-keying (OOK), and selection combining is performed at the receiver, producing a diversity effect within that color cluster. The simulations demonstrate that the proposed RGB MIMO VLC system provides high performance via a relatively simple design of MIMO. Moreover, the proposed system ensures sufficient illumination from LEDs and offers extended distance if more LEDs are applied.

VLC Wireless Data Transmission of High Luminance LED Irradiated by the High Dose-Rate Gamma-Ray (고 선량 감마선 조사에 따른 고휘도 LED의 가시광 무선 데이터 전송)

  • Cho, Jai-Wan;Choi, Young-Soo;Hong, Seok-Boong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.5
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    • pp.996-1000
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    • 2010
  • In order to apply VLC (visible light communication) in harsh environment of nuclear power plant in-containment building, the high luminance LEDs, which are key components of the VLC system, have been gamma irradiated at the dose rate of 4 kGy/h during 72 hours up to a total dose of 288 kGy. The radiation induced coloration effect in the high luminance LED bulb made of acryl or plastic material was observed. In the VLC wireless data transmission experiment using the high luminance LEDs irradiated by high dose rate gamma-ray, the radiation induced coloration effect of the high luminance LED bulb extended the communication distance compared to non-irradiated LEDs.