• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.52-53
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• 2002

파장분할 다중화 광통신 선로 상에서, 특정 파장 채널을 임의로 선택하여 분리/첨가 할 수 있는 동적파장가감기(wavelength-division dynamic optical add-drop multiplexer)는 광 네트워크의 효율을 높이는데 핵심 소자라 할 수 있다. 지난 수년간 개발된 수많은 기술들 중에서, LiNbO$_3$ 광도파로 음향광학소자(acousto-optic tunable filter： AOTF)는 몇 가지의 특징적인 장점들을 보여줬는데, 예를 들면 넓은 영역의 파장 선택성, 짧은 스위칭 시간, 다중 채널 동작 가능성 등이다. (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2000.08a
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• pp.144-145
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• 2000

파장 분할 다중화(WDM)기술은 빠른 속도로 발전해 왔으며, 이에 대한 연구는 계속되고 있다. 전송용량의 증가에 의해 전송 채널의 수가 증가하고 이에 따라 이득 대역도 더 넓어져야한다.$^{(1)}$ 파장 분할 다중화(WDM) 시스템의 구성에서 어븀 첨가 광섬유 증폭기(EDFA)는 시스템의 핵심 요소로 각 단계마다 몇 개씩의 EDFA가 사용된다. EDFA에서는 이득의 변화가 10 ms정도로 천천히 일어나므로 입력의 평균값에 의해 이득이 결정된다. 따라서, EDFA는 모든 채널의 입력의 합이 일정할 때 이득의 상호 포화로 인한 채널 간의 누화가 없다는 장점이 있기 때문에 다채널 WDM 시스템의 광섬유 증폭기로 매우 유용하게 이용되고 있다.$^{(2)}$ (중략)

• ETRI Journal
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• v.9 no.2
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• pp.92-95
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• 1987

코우히어런트 광전송에 관한 연구의 현황을 간략히 기술하였다. 그 내용은 광원인 단일 주파수 레이저의 안정화 방법, 광의 변조 방식, 국부 발진광의 주파수 변환 방법, 평형 광검파 방법, 수신 광신호와 국부 발진광의 편극 상태를 정합시키는 기법 및 파장 분할 다중화 기술등이다.

• Proceedings of the Optical Society of Korea Conference
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• 1997.08a
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• pp.24-24
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• 1997

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.1
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• pp.6-12
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• 2010

Fiber optic sensor using fiber Bragg grating(FBG) probes is used for monitoring strain and temperature distributed on the wide surfaces of large structures. In this paper, in order to use many FBG probes in one optical fiber line, we propose a complex multiplexing technology which is composed of two techniques, one is time division multiplexing and another is wavelength division multiplexing. However, we only investigate the characteristics of time division multiplexing because FBG sensors basically can be operated by wavelength division multiplexing. We calculate the optimal reflectivities and the lengthwise location of five FBG probes in serial connection in order to obtain the unique reflected intensities from the FBG probes. We fabricate five FBG probes with the reflectivities of 13%, 16%, 25%, 40% and 80%, which are determined by the theoretical calculation, and observe the signal reflected from each FBG in the time domain from the experiment. There are differences between experimental and theoretical results caused by the signal noise and the differences of reflectivities of FBG probes. But the experimental results shows the reflected signals of five FBG probes which prove the availability of complex multiplexing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.1
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• pp.67-74
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• 2009

In this paper, we investigate the performance limitations of SubCarrier Multiplexed(SCM) WDM systems using optical Double-Side Band(DSB) modulated 16 QAM signals. The Bit-Error Rate(BER) performance is evaluated under various optical transmission links including the effects of the dispersion and fiber nonlinearities such as SPM(Self-Phase Modulation) and XPM(cross-phase modulation). After simulation of SCM-WDM systems, the dominant factors determining the entire system performance are appeared to be the nonlinearity of MZ(Mach-Zehnder) modulator and the SCM channel spacing. The BER performance of subcarrier channels in the higher frequencies was degraded with the large dispersion effect only, however, the performance was improved a little with a combined effect of fiber dispersion and nonlinear effect when the hish fiber launching power was applied.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.523-524
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• 2006

• 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)

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.40-48
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• 2015

An optical network-on-chip(ONoC) architecture is emerging as a new paradigm for solving on-chip communication bottleneck. Recent studies on ONoC have been focusing on supporting the parallel transmission and avoiding path collisions using wavelength division multiplexing(WDM). However, since the maximum number of wavelengths, which a single waveguide can accommodate is limited by crosstalk and insertion loss. Therefore previous WDM studies based on incrementing the number of different wavelengths according to the number of nodes would be infeasible due to the implementation complexity. To solve such problems, we combined time division multiplexing(TDM) and wavelength-routed ONoC, along with an optimized channel allocation algorithm, which can minimize the number of extra wavelength channels and latency caused by combining TDM scheme.

• Korean Journal of Optics and Photonics
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• v.22 no.3
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• pp.122-128
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• 2011

The AWG-filtering effect was investigated on a bidirectional 100-GHz-channel-spacing WDM-PON link using spectrum-sliced and RSOA-amplified light sources for downstream signals and a wavelength reuse technique for upstream signals. Signal performances of three different filtering AWGs, including Gaussian, trapezoidal, and rectangular types, were compared on link transmission with fiber nonlinear effects. As an extinction ratio of a downstream signal varied, the effect for both directional signals was analyzed and optimized. It was found that there was an optimal pass bandwidth of an AWG for the balance between relative intensity noise decrement and cross phase modulation noise increment as the bandwidth got wider.