• Title/Summary/Keyword: 파장다중분할

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A centralized approach in mult-channel access scheme for single-hop WDM local area networks (단일흡 파장 분할 다중화 지역망을 위한 집중화된 방식의 다중 접근 방안)

  • 오영열;손장우;조원홍;이재용;이상배
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.4
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    • pp.1035-1044
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    • 1998
  • A new multi-channel access scheme and the associated network architecture for a single-hop WDM local area network is proposed in this paper. The proposed architecture has Central Scheduling Node (CSN) for the transmission coordination among many users, which is one of the key issues in single-hop WDM networks. The data channels, source nodes, and destination nodes are selected at CSN in very simple menner. Our scheme can relive the control processing overhead at all nodes in the network which is caused in existing distributed scheduling algorithms. CSN is simple in the architecture can be implemented easily. in respect to the network performance, the maximum obtainable throughput is up to that of the ideal output queuing because of collision free scheduling. We use the MQMS (multi-queue multi-server) model for performance analaysis.

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광통신용 광학 박막의 최신 기술 동향

  • 황보창권
    • The Optical Journal
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    • v.13 no.1 s.71
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    • pp.60-72
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    • 2001
  • 광통신 기술의 발달에 따라 광학 박막을 이용한 광학 소자가 많이 사용되고 있으며, 다양하고 정교한 광학소자로서 광학박막이 계속 많이 사용될 것으로 기대되고 있다. 광통신 광학박막, 파장 다중 분할 필터(WDM), 이득 평탄 필터, 파장 가변 패브리-페로 필터, 증착 방법을 소개한다.

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Optical tunable wavelength add/drop multiplexer employing piezoactuated fiber Bragg gratings for WDM system (압전 소자형 광섬유 격자 소자를 이용한 파장 분할 다중화 시스템용 파장 가변형 광 분기/결합 장치)

  • Kim, Se-Yoon;lee, Sang-Bae;Choi, Sang-Sam;Chung, Joon;Jeong, Ji-Chai
    • Korean Journal of Optics and Photonics
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    • v.8 no.4
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    • pp.340-344
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    • 1997
  • We proposed and demonstrated a tunable wavelength optical add/drop multiplexer(OADM) employing piezoactuated fiber grating pairs and polarization beam splitters. We used piezostack act as a fiber stretcher, using the fact that the resonant wavelength of the grating can be controlled by the axial strain along the fiber grating. The polarization controlled configuration showed high stability because the reflected signals from the two identical gratings are dropped or added not by interference but by polarizations of the beams. We could add and drop not noly 1549.3nm signal channel(original gratings), but also 1550.1nm(tuned gratings) with PZT actuators and in both cases, we found that the rejection of adjacent channels was more than -26dB, and signal leakage at the gratings was less than -34dB.

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Fiber Sensor Network for Vessel Monitoring based on Code Division Multiple Access (코드분할 다중방식을 기반으로 하는 선박 상태 모니터링 광섬유 센서 네트워크)

  • Kim, Young-Bok;Lee, Seong-Ro;Jeon, Sie-Wook;Park, Chang-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.10B
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    • pp.1216-1221
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    • 2011
  • We propose a multiplexed fiber Bragg grating (FBG) sensor network for vessel monitoring to measure the variation of strain and temperature by environmental perturbation based on code division multiple access (CDMA). The center wavelength of FBG was linearly changed by environmental perturbation such as strain and temperature variation so that we could be monitoring the state of sensors. A RSOA was used as optical broadband source and which was modulated by using pseudo random binary sequence (PRBS) signal. The correlation peak of reflected signal from sensor networks was measured. In this paper, we used the sliding correlation techniques for high speed response and dynamic rage of sensors.

초단 광펄스와 광롱신 및 광 신호처리

  • 김경헌
    • Optical Science and Technology
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    • v.7 no.2
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    • pp.40-49
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    • 2003
  • 근래에 들어와 초단 광펄스 생성 기술이 발전되어 다양한 초고속 현상 및 물성 분석 연구에 활용되고 있으며 통신 및 신호처리에 대한 응용 기술에 대해서도 연구되고 있다. 특히 대용량 광통신 기술로는 이미 기술적인 성숙도를 보인 파장분할다중 (WDM) 기술과 더불어 전기적 신호를 다중화하여 광신호로 변환하여 통신하는 전기적 시간분할다중 (ETDM) 기술이 있으며, 초단 광펄스를 이용하는 40 Gbps 급 이상의 고속 광시간분할다중 (OTDM) 광통신 기술도 연구되고 있다. 이 OTDM기술에 있어서는 초단 광펄스 생성 기술과 고속 광신호 다중화 및 역다중화 기술. 광동기신호 재생 기술 등이 주요 핵심 기술을 이루고 있다. 본 글에서는 근래에 들어와 활발히 연구되고 있는 광통신용 펨토초급 초단 광펄스 생성 기술과 이를 이용한 40 Gbps급 이상의 고속 광시간분할다중 (OTDM) 광전송 및 광신호처리에 관련된 기술 현황을 살펴보고자 한다.

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Dense Wavelength-Division Multiplexed Passive Optical Network Employing Wavelength-Locked Fabry-Perot Lasers (파장 고정된 Fabry-Perot 레이저를 사용한 고밀도 파장분할 다중방식 수동형 광통신망)

  • Kim Hyun Deok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.1
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    • pp.33-38
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    • 2005
  • A cost-effective dense WDM-PON employing wavelength-locked Fabry-Perot lasers has been demonstrated. We have successfully demonstrated a dense WDM transmission of 4×622 Mb/s upstream signal with 50-GHz channel spacing over 30-km conventional single mode fiber. We have also investigated the heating noise characteristics of a wavelength-locked Fabry-Perot laser and showed the wavelength-locked Fabry-Perot laser suppresses the intensity noise of the incoherent light injected which enables a dense WDM transmission with a channels spacing of 50 GHz.

Simultaneous Generation of Brillouin Pump and its Brillouin Stokes in Erbium-Doped Fiber Ring Laser (어븀이 도핑된 광섬유 링 레이저에서 브릴루엥 폄프 신호와 브릴루엥 스토크스의 동시 발생)

  • 박갑동;박재형;이재형;장준성
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.08a
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    • pp.142-143
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    • 2000
  • 파장분할 다중화 방식(WDM)이 광통신 시스템의 통신 속도를 획기적으로 향상시키는 방법으로 자리잡음에 따라 다파장 발생에 관한 많은 연구가 이어지고 있다. 지금까지의 연구 결과들은 크게 두가지로 나눌 수 있는 데, 넓은 대역의 이득 매질에서 다양한 방식의 파장선택 특성들을 이용하여 여러 개의 파장을 원하는 간격으로 발생시키는 방법$^{(1).(2)}$ 과 하나의 외부레이저 신호입사에 의한 유도산란을 통하여 일정한 파장간격을 가진 연속차수의 스토크스 신호를 발생시키는 방법$^{(3).(4).(5)}$ 이 있다. (중략)

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Development of 2.5 Gbps Multi-Channel Tunable Wavelength Converter Based on Cross Gain Modulation in Semiconductor Optical Amplifier (반도체 광증폭기의 상호 이득 변조를 이용한 2.5 Gbps 다채널 가변형 파장변환기)

  • Son, Jung-Min;Lee, Sang-Sun
    • Korean Journal of Optics and Photonics
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    • v.16 no.4
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    • pp.392-396
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    • 2005
  • A new structure of tunable wavelength converter based on XCM in SOA was tried and analyzed. This converter used single SOA and had very simple structure. In this paper, results were experimentally obtained and demonstrated. Pump signal was generated with NRZ $(PRBS\;2^{31}-1)$ and data rate 2.5 Gbps. WDM multi conveted signals showed more than 8.3 dB extinction ratio. For BER performance, all these converted signals had within 5.0 dB power penalty compared with the pump signal. With these results, we showed that this converter was suitable for 2.5 Gbps WDM multi-channel wavelength converting.