公开(公告)号：KR100720113B1

公开(公告)日：2007-05-18

申请号：KR1020050098651

申请日：2005-10-19

Applicant: 한국과학기술원

Inventor： 이창희 ,  박근열 ,  문실구

IPC: H04B10/2581 ,  H04B10/2507 ,  H04J14/02 ,  H04L12/28

CPC classification number: H04J14/0226 ,  H04B10/506 ,  H04B10/572 ,  H04J14/02 ,  H04J14/0246 ,  H04J14/025 ,  H04J14/0282

Abstract: The present invention relates to a wavelength-division multiplexed passive optical network (WDM-PON) for reducing degradation in noise characteristic of a wavelength-locked Fabry-Perot Laser Diode (F-P LD). A WDM-PON for reducing degradation in a noise characteristic of a wavelength-locked F-P LD in accordance with the present invention comprises a central office (CO); a remote node (RN) being connected to the CO by a single mode fiber; and one or more optical network terminations (ONTs) being connected to the RN by one or more single mode fibers, respectively, wherein the CO comprises: a broadband light source (BLS) for generating light to be injected; a first wavelength-division multiplexing (WDM) filter for filtering for the injected light generated from the BLS and having a bandwidth wider than a bandwidth of the injected light in order to minimize a filtering effect; and one or more optical transceiver having one or more F-P LDs into which light being filtered by the first WDM filter is injected; and wherein the RN filters the injected light generated from the BLS and injects the filtered light into the one or more ONTs; and wherein the RN comprises a second WDM filter having a bandwidth wider than a bandwidth of the injected light in order to minimize a filtering effect.

公开(公告)号：KR1020050028987A

公开(公告)日：2005-03-24

申请号：KR1020030064970

申请日：2003-09-19

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  박근열

IPC: H04J14/02

CPC classification number: H04J14/0298 ,  H04B10/2581 ,  H04B10/2587 ,  H04J14/0216

Abstract: A wavelength-shared WDM-SCMA(Wavelength Division Multiplexing-Subcarrier Multiple Access) passive optical network is provided to enhance subscriber capacity of a WDM-PON(Passive Optical Network) based optical network by adding separate sub-carriers in a multiplexed optical signal. A central office(CO) includes plural first transceiver(A) and a first WDM multiplexer/demultiplexer. A second WDM multiplexer/demultiplexer and optical splitters(10b) are connected to a remote node(RN). The optical splitters separate or couple signals to n transmission lines at respective ports. A subscriber node includes plural optical network units(ONU11 to ONUn1,ONU12 to ONUn2,ONU1N to ONUnN) connected to the splitter. A single optical fiber(20) couples the first and second WDM multiplexer/demultiplexer and transmits bidirectional signals.

Abstract translation: 提供波长共享的WDM-SCMA（波分复用子载波多址）无源光网络，以通过在复用的光信号中添加单独的子载波来增强基于WDM-PON（被动光网络）的光网络的用户容量。 中心局（CO）包括多个第一收发器（A）和第一WDM多路复用器/解复用器。 第二WDM多路复用器/解复用器和光分路器（10b）连接到远程节点（RN）。 光分路器在各个端口处将信号分离或耦合到n个传输线。 用户节点包括连接到分路器的多个光网络单元（ONU11至ONUn1，ONU12至ONUn2，ONU1N至ONUnN）。 单个光纤（20）耦合第一和第二WDM复用器/解复用器并传输双向信号。

公开(公告)号：KR1020030072786A

公开(公告)日：2003-09-19

申请号：KR1020020011982

申请日：2002-03-06

Applicant: 한국과학기술원

Inventor： 이창희 ,  김성만 ,  백진석 ,  박근열

IPC: G02B6/00

Abstract: PURPOSE: A receiving error rate improving system of a low frequency-added optical signal is provided to lessen the increase of error rate generated due to low frequency modulation effect. CONSTITUTION: According to an optical communication receiver system for improving a receiving error rate of an optical signal using a variable decision threshold signal, a low frequency band extraction unit is connected to the rear of one side of an optical isolator(11) where an optical signal with low frequency modulation is inputted and thus an output optical signal is used as a variable decision threshold signal of a decision circuit(16). And a high frequency signal receiving unit is connected to the rear of another side of the optical isolator and thus the output optical signal is used as a data signal of the decision circuit.

Abstract translation: 目的：提供低频附加光信号的接收误码率改善系统，以减少由于低频调制效应而产生的误码率的增加。 构成：根据用于使用可变判定阈值信号来提高光信号的接收误差率的光通信接收机系统，低频带提取单元连接到光隔离器（11）的一侧的后部，其中光学 输入低频调制信号，由此输出光信号用作判决电路（16）的可变判定阈值信号。 并且高频信号接收单元连接到光隔离器的另一侧的后面，因此输出光信号被用作决定电路的数据信号。

公开(公告)号：KR100541062B1

公开(公告)日：2006-01-10

申请号：KR1020030064970

申请日：2003-09-19

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  박근열

IPC: H04J14/02

Abstract: 본 발명은 WDM PON 기반의 광가입자망에서 파장을 공유하는 RN단을 구성하고, CO단과 가입자단 양단의 광송수신기에 SCM/SCMA를 추가함으로써, 보다 스펙트럼 효율을 향상시키고 쉽게 가입자 수를 늘릴 수 있는 WDM-SCMA 광가입자망의 구조와 상하향신호 전달에 관한것이다.
본 발명에 따른 광가입자망은 광부품에 비해 상대적으로 저렴한 전기적 부품을 추가함으로써 저렴하게 용량을 확대할 수 있는 장점이 있으며, 아울러 하향신호에 SCM을 채용함으로써 CO단의 광원의 개수를 줄여 가입자 수 증가에 따른 광원 단가의 증가를 최소화 할 수 있다.
또한, SCM/SCMA를 혼합할 경우 단일 가입자가 여러 채널의 부반송파 채널을 동시에 송수신 할 수 있으므로 다양한 형태의 서비스를 손쉽게 수용할 수 있으며, 기존의 단일 채널 전송 방법에 비해 다양한 서비스 수용을 위해 송수신기에 추가되는 기능을 크게 간략화 시킬 수 있어 가입자 수 대비 시스템 구현 비용을 획기적으로 절감할 수 있다.
수동형 광가입자망, SCM, SCMA, WDM

公开(公告)号：KR1020050045649A

公开(公告)日：2005-05-17

申请号：KR1020030079806

申请日：2003-11-12

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  최기만 ,  민현식 ,  박근열

IPC: H04B10/2587 ,  H04B10/2581 ,  H04B10/00

CPC classification number: H04B10/502 ,  H01S5/005 ,  H04B10/506 ,  H04J14/02

Abstract: 본 발명은 WDM-PON 기반의 광가입자망에서 사용할 수 있는 파장 잠김된 FP LD를 구현하는데 필요한 광대역 비간섭성 광원에 관한 것으로, 저가의 FP LD의 상호 주입(Mutual Injection)을 이용한 방법과 처핑(Chirping)을 겪은 FP LD를 이용한 방법으로 광대역 비간섭성 광원을 제안한다.
현재 사용되고 있는 광대역 비간섭성 광원으로 LED, SLD, EDFA 등이 있으나, 파워 레벨이 낮거나 소자 자체의 가격이 높은 등의 비효율적인 특성이 있다. 이에 반해, 본 발명에서 제안하는 FP LD를 이용한 광대역 비간섭성 광원은 구성이 매우 간단할 뿐만 아니라 저가로 구현가능하다는 장점을 가진다.

公开(公告)号：KR100380217B1

公开(公告)日：2003-04-16

申请号：KR1020000074462

申请日：2000-12-08

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  박근열

IPC: H04B10/2581

Abstract: PURPOSE: An automatic power control optical amplifier for a WDM(Wavelength Division Multiplexing) optical transmission system and a control method therefor are provided to obtain an excellent gain flattering characteristic by effectively controlling a local power of an output spectrum using a dynamic gain flattering filter. CONSTITUTION: The first amplifying unit(10) has a pump resource(10a) and a gain medium(10b) for providing a gain to an optical signal and controlling a power necessary for amplification. A dynamic gain flattering filter(22) converts a spectrum of the optical signal into a random type. The second amplifying unit(20) has a pump resource(20a) and a gain medium(20b) for providing a gain to the optical signal and controlling the power necessary for amplification. An optical monitoring unit(24) is tapped to the output of the second amplifying unit(20). A control circuit(18b) generates control signals of the dynamic gain flattering filter(22) and the pump resources(10a,20a) using the optical spectrum obtained from the optical monitoring unit(24).

Abstract translation: 目的：提供一种用于WDM（波分复用）​​光传输系统的自动功率控制光放大器及其控制方法，以通过使用动态增益平滑滤波器有效地控制输出频谱的局部功率来获得优异的增益平滑特性。 构成：第一放大单元（10）具有用于向光信号提供增益并控制放大所需的功率的泵浦源（10a）和增益介质（10b）。 动态增益平滑滤波器（22）将光信号的频谱转换为随机类型。 第二放大单元（20）具有用于向光信号提供增益并控制放大所需的功率的泵资源（20a）和增益介质（20b）。 光监控单元（24）被分接到第二放大单元（20）的输出端。 控制电路（18b）利用从光学监视单元（24）获得的光谱来生成动态增益平滑滤波器（22）和泵浦资源（10a，20a）的控制信号。

公开(公告)号：KR1020070025885A

公开(公告)日：2007-03-08

申请号：KR1020050098651

申请日：2005-10-19

Applicant: 한국과학기술원

Inventor： 이창희 ,  박근열 ,  문실구

IPC: H04B10/2581 ,  H04B10/2507 ,  H04J14/02 ,  H04L12/28

CPC classification number: H04J14/0226 ,  H04B10/506 ,  H04B10/572 ,  H04J14/02 ,  H04J14/0246 ,  H04J14/025 ,  H04J14/0282

Abstract: A WDM(Wavelength-Division Multiplexed) PON(Passive Optical Network) for reducing degradation of a noise characteristic of a wavelength-locked Fabry-Perot LD(Laser Diode) is provided to maximally use reduction effect of output noise of a wavelength-seeded reflective semiconductor optical amplifier, thus high-speed transmission at more than 1Gb/s is available. A central office(100) comprises the followings. A BLS(Broadband Light Source)(130b) forms broadband light. The first WDM filter filters the formed light, and has a wider bandwidth than that of the injected light. The light filtered from the first WDM filter is injected into plural optical transceivers(110a-110n). A remote node(200) comprises the second WDM filter filters which filters the broadband light formed in the BLS(130b) to inject the filtered light into plural ONTs(Optical Network Terminations)(300), and which has a wider bandwidth than that of the injected light.

Abstract translation: 提供了用于减少波长锁定法布里 - 珀罗LD（激光二极管）的噪声特性降低的WDM（波分复用）​​PON（无源光网络），以最大限度地利用波长种子反射的输出噪声的降低效果 半导体光放大器，因此高速传输超过1Gb / s。 中央办公室（100）包括以下内容。 BLS（宽带光源）（130b）形成宽带光。 第一个WDM滤波器对形成的光进行滤波，并且具有比注入光更宽的带宽。 从第一WDM滤波器滤波的光被注入到多个光收发器（110a-110n）中。 远程节点（200）包括第二WDM滤波器滤波器，其对形成在BLS（130b）中的宽带光进行滤波，以将经滤波的光注入到多个ONT（光网络终端）（300）中，并且具有比 注射光。

公开(公告)号：KR100566903B1

公开(公告)日：2006-04-03

申请号：KR1020030079806

申请日：2003-11-12

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  최기만 ,  민현식 ,  박근열

IPC: H04B10/2587 ,  H04B10/2581 ,  H04B10/00

Abstract: 본 발명은 WDM-PON 기반의 광가입자망에서 사용할 수 있는 파장 잠김된 FP LD를 구현하는데 필요한 광대역 비간섭성 광원에 관한 것으로, 저가의 FP LD의 상호 주입(Mutual Injection)을 이용한 방법과 처핑(Chirping)을 겪은 FP LD를 이용한 방법으로 광대역 비간섭성 광원을 제안한다.
현재 사용되고 있는 광대역 비간섭성 광원으로 LED, SLD, EDFA 등이 있으나, 파워 레벨이 낮거나 소자 자체의 가격이 높은 등의 비효율적인 특성이 있다. 이에 반해, 본 발명에서 제안하는 FP LD를 이용한 광대역 비간섭성 광원은 구성이 매우 간단할 뿐만 아니라 저가로 구현가능하다는 장점을 가진다.
광가입자망, 비간섭성 광원, 패브리 페롯 레이저 다이오드, 상호주입, 처핑

公开(公告)号：KR100473520B1

公开(公告)日：2005-03-10

申请号：KR1020020083410

申请日：2002-12-24

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  박근열 ,  장승현 ,  최기만 ,  민현식

IPC: H04L12/28

CPC classification number: H04J14/0226 ,  H04J14/0227 ,  H04J14/0246 ,  H04J14/0247 ,  H04J14/025 ,  H04J14/0252 ,  H04J14/0282 ,  H04L12/2801

Abstract: The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical network. The passive optical network includes light providing means provided in a central office to provide broadband incoherent light; a multiplexer connected to the central office via an optical fiber to divide the light transmitted from the light providing means according to wavelengths and to multiplex upstream signals; a plurality of splitters to branch divided lights and to combine the upstream optical signals; and a plurality of subscribers connected to the splitters, the subscribers including wavelength-locked Fabry-Perot laser diodes capable of performing direct and analog modulation, and means for directly modulating lights of the Fabry-Perot laser diodes and transmitting modulated lights to the subscribers using time division multiplexing.

公开(公告)号：KR1020040056828A

公开(公告)日：2004-07-01

申请号：KR1020020083410

申请日：2002-12-24

Applicant: 한국과학기술원

Inventor： 이창희 ,  백진석 ,  박근열 ,  장승현 ,  최기만 ,  민현식

IPC: H04L12/28

CPC classification number: H04J14/0226 ,  H04J14/0227 ,  H04J14/0246 ,  H04J14/0247 ,  H04J14/025 ,  H04J14/0252 ,  H04J14/0282 ,  H04L12/2801

Abstract: PURPOSE: An optical subscriber network using an FP-LD(Fabry-Perot Laser Diode) by injecting external incoherence light source is provided to enhance spectrum efficiency of a subscriber network at a low cost and remarkably increase the number of subscribers per line. CONSTITUTION: Uplink signals from a subscriber to central base station(71) are grouped according to wavelength division port of a multiplier(73), and each port is connected to light sources of each subscriber terminal sharing wavelength through a splitter(74). When a central base station(71) transmits a noncoherent light source(72) having a wider wavelength range, the light source is filtered at each port of the multiplexer(73) and then injected to the FP-LD of grouped subscriber terminals through the splitter(74). In this manner, the oscillation wavelength of the FP-LD is determined by the noncoherent light source injected from the outside, and output power of the wavelength-fixed FP-LD is used as an uplink transfer signal light source of each subscriber.

Abstract translation: 目的：提供通过注入外部不相干光源使用FP-LD（法布里 - 珀罗激光二极管）的光用户网络，以便以低成本提高用户网络的频谱效率，并显着增加每行用户数量。 构成：从用户到中央基站（71）的上行链路信号根据乘法器（73）的波长分配端口分组，并且每个端口通过分路器（74）连接到每个用户终端共享波长的光源。 当中央基站（71）发射具有较宽波长范围的非相干光源（72）时，光源在多路复用器（73）的每个端口处被滤波，然后通过该多路复用器（73）被注入分组用户终端的FP-LD 分离器（74）。 以这种方式，FP-LD的振荡波长由从外部注入的非相干光源确定，波长固定的FP-LD的输出功率用作每个用户的上行链路传输信号光源。