公开(公告)号：KR100698766B1

公开(公告)日：2007-03-23

申请号：KR1020050083256

申请日：2005-09-07

Applicant: 한국과학기술원

Inventor： 이창희 ,  박주희

IPC: H04B10/07 ,  H04J14/02 ,  H04B10/2581

CPC classification number: H04B10/071 ,  H04J14/02 ,  H04J14/0282 ,  H04J14/0287

Abstract: 본 발명은 파장 분할 다중 방식 수동형 광 가입자 망(WDM-PON) 시스템에 사용되는 광 선로의 장애 위치를 감시하는 장치 및 이를 구비한 파장분할 다중방식 수동형 광 가입자 망 시스템을 개시한다.
본 발명의 장애 위치 감시 장치는 상기 하나의 광 선로 상에서 발생하는 장애 위치를 찾기 위한 감시용 전기 펄스 신호를 발생시키는 신호 발생기; 상기 신호 발생기에 의해 변조되며, 상기 펄스 신호를 감시광으로 변환하여 출력하는 광원; 파장을 변화시키면서 일정한 파장 대역의 광만 통과시키는 가변 대역통과 필터; 상기 광원에 주입되는 광을 출력하는 새로운 대역의 비간섭성 광원 (N-BLS); 상기 N-BLS로부터 출력되는 비간섭성 광을 상기 가변 대역통과 필터를 통해 상기 광원에 입력되도록 우회시키고, 상기 광원으로부터 출력되며, 상기 가변 대역통과 필터를 통과한 상기 감시광을 상기 하나의 광 선로로 우회시키는 4-포트 광 회전기; 상기 4-포트 광 회전기에 의해 우회되는, 상기 하나의 광 선로 상에서 후방 산란 및 반사된 감시광을 수신하며, 수신된 상기 감시광을 전기 신호로 변환하여 출력하는 광 검출기; 상기 광 검출기로부터 출력되는 상기 변환된 감시광의 잡음을 제거하여 출력하는 신호처리부; 및 상기 신호처리부로부터 출력되는 신호를 표시하는 디스플레이부를 포함한다.
광대역 비간섭성 광원(BLS), 파장분할 다중방식 수동형 광 가입자 망(WDM-PON), 장애 위치 감시 장치

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：KR100683833B1

公开(公告)日：2007-02-16

申请号：KR1020050131999

申请日：2005-12-28

Applicant: 한국과학기술원

Inventor： 이창희 ,  이상묵 ,  문실구

IPC: H04B10/2581 ,  H04L12/28

Abstract: A multi-star WDM(Wavelength Division Multiplexing) PON(Passive Optical Network) using a wavelength allocation method is provided to easily maintain and manage a system by using the same type of an optical transmitter/receiver having a filter that splits only a base band, in every subscriber unit. A central station includes a WDM and an optical transmitter/receiver. The first RN(Remote Node) is connected with the central station by an optical fiber, splits downlink signal wavelength bands into several lower wavelength bands and combines uplink signal wavelength bands split into several lower wavelength bands, and includes a BSWDM(Band Splitting WDM) in which a guard band between basic bands used as an uplink signal wavelength band and a downlink signal wavelength band follows a certain equation. A plurality of the second RNs are connected with the first RN through several optical fibers and includes a WDM. ONTs(Optical Network Terminations) are connected with the second RNs through individual optical fibers and include an optical transmitter/receiver.

Abstract translation: 提供使用波长分配方法的多星级WDM（波分复用）​​PON（无源光网络），以通过使用具有仅分割基带的滤波器的相同类型的光发送器/接收器来容易地维护和管理系统 ，在每个用户单元中。 中心站包括WDM和光发射机/接收机。 第一个RN（远程节点）通过光纤与中心站连接，将下行链路信号波长带分成几个较低波长带，并组合分成几个较低波长带的上行链路信号波长带，并且包括BSWDM（波段分离WDM） 其中用作上行链路信号波段和下行链路信号波段的基带之间的保护带遵循一定的等式。 多个第二RN通过多根光纤与第一RN连接，并且包括WDM。 ONT（光网络终端）通过单根光纤与第二个RN连接，并包括光发射机/接收机。

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。

公开(公告)号：KR100411734B1

公开(公告)日：2003-12-18

申请号：KR1020010006738

申请日：2001-02-12

Applicant: 한국과학기술원

Inventor： 이창희 ,  박성범

IPC: H04L12/42

Abstract: PURPOSE: A bidirectional WDM(Wavelength Division Multiplex) add/drop self-recovery ring-shaped metro network is provided to perform self-recovery using only one optical fiber without a specific optical switch on a transmission line when a WDM optical signal is bidirectionally transmitted in a CO(Central Office) and each RN(Remote Node) and the fault of a system is generated. CONSTITUTION: One CO and a plurality of RNs(RN1-RN3) are composed in the bidirectional WDM add/drop self-recovery ring-shaped metro network. Nodes are connected by a ring-shaped type through one optical fiber(1) for bidirectionally transmitting and receiving an optical signal. Each RN(RN1-RN3) is embodied as a BADM(Bidirectional Add/Drop Multiplexer) so that a specific wavelength signal is dropped and added in each RN(RN1-RN3).

Abstract translation: 目的：提供双向WDM（波分复用）​​分插自恢复环形城域网络，当WDM光信号双向传输时，在传输线路上仅使用一根光纤而不需要特定的光开关来执行自恢复 在CO（中心局）和每个RN（远程节点）中，并且生成系统故障。 组成：一个CO和多个RN（RN1-RN3）由双向WDM分插自恢复环形城域网组成。 节点通过一个光纤（1）通过环形类型连接，用于双向传输和接收光信号。 每个RN（RN1-RN3）被实现为BADM（双向分插复用器），使得特定波长信号被分出并被添加到每个RN（RN1-RN3）中。

公开(公告)号：KR100405820B1

公开(公告)日：2003-11-14

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：提供一种低频附加光信号的接收错误率改善系统，以减少由于低频调制效应而产生的错误率的增加。 本发明公开了一种光通信接收机系统，该光通信接收机系统使用可变判定阈值信号来提高光信号的接收错误率，并将低频带提取单元连接到光隔离器（11）的一侧的后部， 输入具有低频调制的信号，因此输出光信号被用作判定电路（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部，因此输出光信号被用作判定电路的数据信号。

公开(公告)号：KR1020030086223A

公开(公告)日：2003-11-07

申请号：KR1020030008099

申请日：2003-02-10

Applicant: 한국과학기술원

Inventor： 이창희 ,  김현덕

IPC: G02B6/293

CPC classification number: H04J14/02 ,  H04B10/503 ,  H04B10/506 ,  H04B10/572

Abstract: PURPOSE: A method and an apparatus for forming a tunable light source and an optical transmission device of a wavelength division multiplexing method using a light source of the same are provided to reduce a manufacturing cost of the light source by using a low-priced Fabry-Perot Laser Diode. CONSTITUTION: An apparatus for forming a tunable light source includes a broad-band light source(BLS), a tunable band-pass filter(TBPF), a Fabry-Perot Laser Diode(FPLD), an optical circulator(OC). The broad-band light source(BLS) is used for outputting the light of broad band. The tunable band-pass filter(TBPF) is used for varying a passing band and passing selectively only the components of the passing band from the outputs of the broad-band light source(BLS). The Fabry-Perot Laser Diode(FPLD) is used for providing the output corresponding to the wavelength of the received light. The optical circulator(OC) is connected between the tunable band-pass filter(TBPF) and the Fabry-Perot Laser Diode(FPLD) in order to transmit the received light to the Fabry-Perot Laser Diode(FPLD) or transmit the output of the Fabry-Perot Laser Diode(FPLD) to the outside.

Abstract translation: 目的：提供一种用于形成可调谐光源的方法和装置以及使用其光源的波分复用方法的光传输装置，以通过使用低价格法布里方程式来降低光源的制造成本， 珀罗激光二极管 构成：用于形成可调谐光源的装置包括宽带光源（BLS），可调谐带通滤波器（TBPF），法布里 - 珀罗激光二极管（FPLD），光循环器（OC）。 宽带光源（BLS）用于输出宽带光。 可调谐带通滤波器（TBPF）用于改变通带并且仅选择通过波段的分量从宽带光源（BLS）的输出通过。 法布里珀罗激光二极管（FPLD）用于提供对应于接收光的波长的输出。 光环行器（OC）连接在可调谐带通滤波器（TBPF）和法布里 - 珀罗激光二极管（FPLD）之间，以将接收到的光传输到法布里 - 珀罗激光二极管（FPLD）或传输 法布里 - 珀罗激光二极管（FPLD）到外面。

公开(公告)号：KR100378677B1

公开(公告)日：2003-03-31

申请号：KR1020000045367

申请日：2000-08-04

Applicant: 한국과학기술원

Inventor： 이창희 ,  오태원 ,  김현덕 ,  신정훈 ,  조윤희

IPC: G02B5/20

CPC classification number: G02B6/272 ,  G02B6/2746 ,  G02B6/2766 ,  H01S3/0064 ,  H01S3/06754

Abstract: The present invention relates to an apparatus and a method for a Non-Reciprocal Optical Wavelength Filter (NRWF) suitable for bidirectional optical transmissions, communications, and amplifiers. The NRWF of the present invention is composed of (1) a Reciprocal Rotator (RR) rotating the polarization state of the light reciprocally, (2) a non-reciprocal Faraday Rotator (FR) rotating the polarization state non-reciprocally according to the propagating direction, (3) two polarization beam splitters, BC1 and BC2, splitting an unpolarized wave into two orthogonally polarized waves, or combining the two orthogonally polarized waves, and (4) a Wavelength Dependent Polarization Converter (WDPC) changing the polarization state according to the wavelength of light. Accordingly, the NRWF has periodic transfer spectra, and the peaks of the transfer spectrum from Port 1 to Port 2 are located between those of the transfer spectrum form Port 2 to Port 1. Therefore, the NRWF of the invention suppresses multiple reflections in wavelength interleaved bidirectional transmissions. The optical amplifiers with the NRWF of the invention are useful for long-haul bidirectional systems and networks.

Abstract translation: 本发明涉及适用于双向光学传输，通信和放大器的非互惠光波长滤波器（NRWF）的设备和方法。 本发明的NRWF由以下部分组成：（1）往复旋转光的偏振状态的倒易旋转器（RR），（2）根据传播不旋转地旋转偏振状态的非互易法拉第旋转器（FR） （3）两个偏振分束器，BC1和BC2，将非偏振波分成两个正交偏振波，或合并两个正交偏振波，（4）波长相关偏振转换器（WDPC），根据 光的波长。 因此，NRWF具有周期性转移光谱，并且从端口1到端口2的转移光谱的峰值位于从端口2到端口1的转移光谱的峰值之间。因此，本发明的NRWF抑制了波长交错的多次反射 双向传输。 具有本发明的NRWF的光放大器可用于长途双向系统和网络。