• 대한전자공학회논문지SD
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• 제37권9호
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• pp.23-30
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• 2000

본 논문에서는 InGaAs/InAlAs 다중 양자우물을 이용한 두가지 타입의 비대칭 Fabry-Perot 전광 스위치에 대한 해석을 시도하였다. 전광 스위치의 동작을 해석하기 위해서 먼저 양자우물의 광 흡수계수와 굴절율의 변화 특성을 계산하였다. 양자우물의 비선형성 해석 결과를 토대로 전광 수위치의 ON/OFF 비와 스위칭 속도를 비교하였다. 시뮬레이션 결과로부터, DBR을 이용한 구조의 전광 수위치는 DBR이 없는 형태의 전광 수위치보다 ON/OFF 비를 향상시킬 수 있을 뿐만 아니라 스위칭 시간도 단축시킬 수 있음을 알 수 있었다.

• Journal of Electrical Engineering and information Science
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• 제3권3호
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• pp.336-341
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• 1998

We describe the architecture of an optical cross-connect (OXC) which is modular in structure and is able to be upgraded to a virtual wavelength path by adding wavelength converters. The additional feature of the OXC is the all-optical nature. It can be implemented with commercial components including mechanical optical switches. As a result of the test on the experimental OXC, it has been shown that 2.5 Gb/s signal can be transmitted via the OXC through 100 km length o an ordinary single mode fiber with 3 dB penalty.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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• pp.116-117
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• 2000

전광 네트워크(All-optical Network)에서 중요한 기능을 담당하는 전광 교환기는 전광 교환 소자 (All-optical Switching Element)로 이루어져 있는데, 각 교환 소자들은 스위칭 모듈(SM), 라우팅 제어 처리기(RCP), 헤더 처리 모듈(HPM), 그리고 입/출력 인터페이스 모듈(IIM, OIM)로 이루어져 있다. 스위칭 시스템 내에 도착하는 패킷은 원하는 스위치의 출력단에 도착하기 전에 많은 교환 소자(SE)들을 지나가게 되는데, 이 때 수많은 패킷들이 서로 충돌하게 되며, 이 과정에서 패킷이 손실된다. (중략)

• 한국광학회:학술대회논문집
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• 한국광학회 1995년도 광학 및 양자전자학 워크샵 논문집
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• pp.210-215
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• 1995

Technology development toward the use of LiNbO3-based acoustic tunable filters as WDM 2$\times$2 cross-connect switches is reviewed. Recenly, it was found that a fundamental behavior of multi-wavelength Bragg scattering critically affects the crosstalk performance of the acousto-optic tunable filter. We revuew serveral reported methods of overcoming the performance degradation. We will eventually ask whether the device is up to task of WDM optical switching.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1261-1263
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• 1997

Two kinds of optically-triggered p-i-n switches with planar and V-groove structures have been fabricated with gold-doped silicon. The V-groove device exhibits a higher threshold voltage and is more sensitive to light. The minimum optical power indicates that a certain minimum illumination is required to optically turn on the silicon p-i-n devices.

• 전자공학회논문지D
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• 제34D권1호
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• pp.41-48
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• 1997

Design rules of directional coupler optical switches are discussed in consideration of parasitic couplings in the bending section. The parasitic coupling phenomenon is analyzed based on the coupled-mode theory and the solutions are represented in the form of the transfer matrix. The modified switching conditions due to the parasitic coupling are derived and the resultant switching diagrams are illustrated. It is revealed that the parallel section's length needs to be adjustd less than the coupling length $l_c(=\pi/2\textsc{k}o)$ to obtain the desired crosstalk and that the adjustment depends on the strength of the parasitic coupling. However, it is discovered that, for weak parasitic coupling, the switching voltage does not need to be altered but may maintain the same value as if no parasitic coupling is taken into account.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2006년도 하계학술대회
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• pp.19-23
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• 2006

Latching optical switches and optical logic gates AND and OR are demonstrated, for the first time, by the monolithic integration of a vertical cavity lasers with depleted optical thyristor structure, which have not only a low threshold current with 0.65 mA. but also a high on/off contrast ratio more than 50 dB. By simple operating technique with changing a reference switching voltage, this single device operates as two logic functions, optical logic AND and OR. The thyristor laser fabricated using the oxidation process achieved a high optical output power efficiency and a high sensitivity to the optical input light.

• 한국광학회지
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• 제14권4호
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• pp.466-472
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• 2003

본 논문에서는 서로 다른 길이의 광섬유 지연선로를 광 2${\times}$2 MEMS 스위치로 선택하여 위상 배열 안테나의 각 안테나 소자에 급전되는 RF 신호의 위상을 고속으로 제어할 수 있는 광 실시간 지연선로의 구조를 제안하였다. RF 신호의 주사 방향이 8개인 10 GHz 선형 위상 배열 안테나용 광 실시간 지연선로를 구현하였으며, 실험 결과 최대 시간 지연 오차가 0.2 ps이하, 즉 최대 주사 각 오차 0.84$^{\circ}$로 측정되었다. 또한 제안된 실시간 지연선로에 의해 구동되는 8개의 마이크로 스트립 패치 안테나 소자로 구성된 10 GHz용 선형 위상배열 안테나를 설계하였고, 시뮬레이션을 이용하여 이 안테나의 방사 패턴을 분석하였다.

• Current Optics and Photonics
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• 제2권1호
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• pp.23-26
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• 2018

Optical-layer restoration has been demonstrated with a wavelength-blocker (WB) -based reconfigurable optical add/drop multiplexer (ROADM). Two $2{\times}2$ optical switches with a control circuit were placed before and after a WB-based ROADM to provide automatic path restoration under fiber-failure conditions. Using the proposed node configuration, a 3-node self-healing ring (SHR) network has been implemented to demonstrate the feasibility of the automatic optical-layer restoration. From the results, the restoration time was measured to be ~4 ms under fiber-failure conditions, without any additional power penalty in receiver sensitivity.

• 제어로봇시스템학회논문지
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• 제9권3호
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• pp.251-258
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• 2003

Optical Switching Matrix (OSM) or Optical Multistage Interconnection Networks (OMINs) comprising photonic switches have been studied extensively as important interconnecting blocks for Optical Cross Connects (OXC) based on Optical Burst Switching (OBS). A basic element of photonic switching networks is a 2$\times$2 directional coupler with two inputs and two outputs. This paper is concerned with the diagnosis of multiple crosstalk-faults in OSM. As the network size becomes larger in these days, the conventional diagnosis methods based on tests and simulation become inefficient, or even more impractical. We propose a simple and easily implementable algorithm for detection and isolation of the multiple crosstalk-faults in OSM. Specifically. we develop an algorithm for isolation of the source fault in switching elements whenever the multiple crosstalk-faults arc detected in OSM. The proposed algorithm is illustrated by an example of 16$\times$16 OSM.