Electronics and Telecommunications Research Institute

Kwangjoon Kim

Joon Ki Lee

Je Soo Ko

Jyung Chan Lee

Jongho Kim

Jong-Yoon Shin

Hwan Seok Chung

Sun Hyok Chang

Hee Sang Chung

Sang Soo Lee

Hyun Jae Lee

Jong Hyun Lee

Yool Kwon

Han Hyub Lee

Seung-Il Myong

Seung Il Myong

Seong-Soon Joo

Sanghwa Yoo

Jyung-Chan Lee

Hae Geun Kim

Jinsoo Han

Donghan Lee

Youn Seon Jang

Young Hwa Kim

Yun Hee Cho

Byoung-whi Kim

Kye-Hyun Ahn

Yun-Hee Cho

Joon-Ki Lee

Moo-Jung Chu

Youn-Seon Jang

An optical signal transmission apparatus including a temperature-independent wavelength tunable laser includes a distributed Bragg reflector (DBR) laser including a DBR mirror region configured to convert a wavelength of an output optical signal based on a first supply current, and an optical gain region configured to control a gain of the output optical signal based on a second supply current, a semiconductor optical amplifier (SOA) configured to amplify an optical signal output from the DBR laser based on a third supply current, and a processor configured to supply a compensation current to the optical gain region based on a wavelength conversion request, to suppress a wavelength overshoot due to a carrier effect caused by the first supply current provided to the DBR mirror region.

Optical signal transmission apparatus including temperature-independent wavelength tunable laser, and wavelength tuning method using the same

A method of transmitting data in an optical transport network is provided. The method comprises generating an optical transmission unit frame including an in-band area including a first area to which information data is allocated and a second area to which the information data is not allocated and an out-band area including parity information and transmitting the data through the optical transmission unit frame.

Method and apparatus for transmitting data in optical transport network

A plurality of lanes are formed between an Ethernet apparatus and a remote Ethernet apparatus. The Ethernet apparatus determines a transmission rate for transmitting a packet and determines the number of lanes to transmit a packet among a plurality of lanes according to the determined transmission rate. The Ethernet apparatus activates the determined number of lanes of a plurality of lanes and transmits the packet to the remote Ethernet apparatus through the activated lanes. Further, the Ethernet apparatus sets the number of lanes for receiving a packet according to a transmission rate, activates the set number of lanes of a plurality of lanes in a state that can receive the packet according to the set number of lanes, and receives packets that are transmitted from the remote Ethernet apparatus through the activated lanes.

Ethernet apparatus and method of adjusting transmission rate thereof

A transmitting apparatus in a transport network, which performs forward error correcting encoding for each virtual lane set, which is a multiple of the number of transmission channels, in order to generate virtual frames including independent parity bytes for each of the virtual lanes. These generated virtual frames are transmitted through at least one transmission channel. A receiving apparatus for detecting the virtual frames for each virtual lane from a signal received through a transmission channel by using a frame assignment sequence, and performing forward error correcting decoding by using the parity bytes included in the virtual frames detected for each virtual lane.

Apparatus and method for transmitting and receiving data

An optical transceiver which can effectively reduce optical output jitter when an error is made during designing and manufacturing of a printed circuit board (PCB), and a method of controlling optical output jitter using the optical transceiver are provided. The optical transceiver includes a transmitter unit including an equalizing (EQ) filter which can reduce jitter of a high speed electric signal; a control circuit which controls the EQ filter; a receiver unit which receives an optical signal; and a micro-controller which controls the transmitter unit and the receiver unit. Further included in the optical transceiver is an active type or passive type EQ filter and, in the case of the active type, the control circuit is used to control the filter, in order to compensate for high-frequency component of a high speed electric signal in the transmitter unit in order to reduce reflection or loss on the PCB, and thus deterministic optical output jitter occurring due to Inter-Symbol Interference (ISI) can be reduced.

Optical transceiver and method of controlling optical output jitter using the same

An optical node capable of supporting a mesh-type optical network is provided. The node includes: N ROADMs, which separate specific wavelength channels from a multiple wavelength channel optical signal that is input from any node constituting the optical network, allows the rest of the wavelength channels to be passed, and combine another added wavelength channel with the passed wavelength channel to allow the combined wavelength channel to be passed; an N&#xd7;1 optical switch which selects the specific wavelength channel separated from one of the N ROADMs and inputs the specific wavelength channel into an optical transceiver and selects one of the N ROADMs and connects a wavelength channel that is output from the optical transceiver to the selected ROADM; and an electrical cross connect switch which drops a part of electrical signal bandwidth of the specific wavelength channels separated by the ROADM, which is converted into the electrical signals in the optical transceiver, toward an external client and combines the rest of the electrical signal bandwidth with a electrical signal added by the external client to form an electrical signal bandwidth of a wavelength channel and output the electrical signal to the optical transceiver. Accordingly, optical fiber inputs and outputs in various directions can be supported, and the number of WDM transceivers used for each node is remarkably reduced, thereby improving efficiency and economical efficiency of a network.

Optical node for mesh-type WDM optical network

Provided are an apparatus and method for maintaining an constant extinction ratio of a laser diode (LD). The apparatus includes: an automatic power control circuit maintaining the constant optical power of the LD; a correlation deriver deriving correlations between a bias current of the LD and a modulation current to maintain the constant extinction ratio of the LD; and a modulation current control circuit controlling the modulation current to maintain constant the extinction ratio of the LD based on the correlations. The apparatus and method do not use a temperature sensor but derive a relationship between variances of a bias current of the LD and a modulation current according to temperature change, control the modulation current based on the relationship, and maintain the constant extinction ratio of the LD.

Apparatus and method for maintaining constant extinction ratio of laser diode

In a conventional network for transmitting an optical burst signal, it is impossible to effectively swap labels, reproduce a payload signal, and switch and transmit the signals. A device for swapping optical labels and reproducing an optical payload, includes: an envelope detection unit outputting an envelope of payloads or labels of an optical burst signal by converting phases of two signals obtained by converting the optical burst signal into an electrical signal; a payload processing unit extracting a payload signal, which is included in the optical burst signal, by synchronizing the optical burst signal with the envelope output from the envelope detection unit and optically reproducing or wavelength-converting the extracted payload signal; and a label processing unit extracting a label signal, which is included in the optical burst signal, by synchronizing the optical burst signal with the envelope output form the envelope detection unit and converting the extracted label signal according to a path along which the optical burst signal is transmitted. Accordingly, it is possible to effectively swap the labels, reproduce the payload signal, and switch and transmit the signals, in the network for transmitting the optical burst signal.

Device and method of swapping optical labels and reproducing optical payload and optical switching device using the device

Provided is a method and system for confirming label switched path (LSP) connection in a global multi-protocol label switching (GMPLS)-based network. The method includes: collecting LSP hierarchy information; selecting one of a plurality of paths between first and second clients according to the LSP hierarchy information; and confirming the connection of the selected path.

Method and system for confirming connection of layer-1 label switched path(L1-LSP) in GMPLS-based network

Provided are a photonic cross-connector system, a wavelength division multiplexing (WDM) system using the photonic cross-connector system, and an optical communication network based on the WDM system. The photonic cross-connector system includes: an optical coupler branching an input optical signal into a plurality of paths; a wavelength selective switch (WSS) extracting at least one wavelength signal from the input optical signal and outputting the extracted wavelength signal to at least one port; a WDM multi-casting apparatus simultaneously copying and reproducing the input optical signal into different wavelengths and changing modulation methods of the input optical signal into different types of modulation methods; an optical transmitter and/or receiver branching and coupling the input optical signal; and a control system controlling the optical coupler, the WSS, the WDM multicasting apparatus, and the optical transmitter and/or receiver.

Photonic cross-connector system, WDM system using the same photonic cross-connector, and optical communication network based on the same WDM system

Provided is an optical transponder that receives a tributary signal such as a SDH/SONET signal, a GbE (Gigibit Ethernet) signal, and a SAN (Storage Area Network) signal in a WDM (Wavelength Division Multiplexing) transmission system and a SDH (Synchronous Digital Hierarchy)/SONET (Synchronous Optical Network) system, and more particularly, to an optical transponder having a switching function. The optical transponder having a switching function includes: a switch changing a data path of an input tributary signal from a plurality of channels (ports); an STM-64/OC-192 mapper/demapper mapping the tributary signal switched to a different data path by the switch to an STM-64/OC-192 signal or demapping the STM-64/OC-192 signal to the tributary signal; and a transmission delay time compensator compensating for a differential delay caused by a transmission route difference on an optical fiber link when the STM-64/OC-192 signal is demapped to the tributary signal.

Optical transponder having switching function

Provided are an optical transponder that processes a G.709 frame that includes an overhead for operation, administration, and maintenance of an optical channel and an overhead for forward error correction, and a method of detecting and treating errors in optical-channel sublayers of the same. The method includes detecting an error signal or a maintenance signal from a G.709 frame that includes an overhead for operation, administration, and maintenance of an optical channel and an overhead for forward error correction; treating errors in a predetermined layer of a plurality of layers that requires error treatment when the error signal or the maintenance signal is detected or canceled; and investigating a reason for the errors in the predetermined layer.

Growing community of inventors

Daejeon, South Korea

Kwangjoon Kim