Supervisory Signal By Repeater Patents (Class 398/181)
  • Patent number: 9215137
    Abstract: A failure is detected in a middle path of communication information received from one communication network. When the communication information received from the one communication network is relayed to another communication network, information is output to the other communication network by storing information about the failure detected from the communication information received from the one communication network in a header of communication information to be output to the other communication network.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: December 15, 2015
    Assignee: NEC Corporation
    Inventor: Toshiro Yamauchi
  • Patent number: 9191118
    Abstract: An optical transceiver module includes N light sources, N light detectors, a bidirectional fiber port, and an optical network having 2N?1 wavelength-selective elements. The number 2N represents the total number of transmit and receive channels in a bidirectional system in which transmit and receive signals corresponding to the transmit and receive channels. Each light source corresponds to one transmit channel and emits an optical transmit signal having a unique transmit wavelength. Each light detector corresponds to one receive channel and detects an optical receive signal having a unique receive wavelength. The optical network couples each light source to the bidirectional fiber port via a corresponding transmit path through the optical network. The optical network further couples each light detector to the bidirectional fiber port via a corresponding receive path through the optical network. Each transmit and receive path includes some of the wavelength-selective elements.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: November 17, 2015
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: David Chak Wang Hui, Xiaozhong Wang
  • Patent number: 9166679
    Abstract: An optical amplification apparatus includes an optical amplification medium configured to receive a first light signal from an end of the optical amplification medium and a second light signal from the other end of the optical amplification medium in opposite directions, the first and second light signals being branched from a light signal, an excitation light source configured to supply excitation light to the optical amplification medium through a multiplexer, a monitor configured to monitor the first and second light signals input to the optical amplification medium, respectively and to output monitoring signals respectively, and a controller configured to control the excitation light source in accordance with the monitoring signals.
    Type: Grant
    Filed: March 21, 2012
    Date of Patent: October 20, 2015
    Assignee: FUJITSU LIMITED
    Inventor: Norifumi Shukunami
  • Patent number: 9014569
    Abstract: In an optical node, a transmitter produces an optical supervisory signal for supervising an optical network, a processor is operative to control a power level of the optical supervisory signal according to a per-wavelength power level of an optical communication signal when the optical node has no post amplifiers, and a multiplexer combines the controlled optical supervisory signal with the optical communication signal to be transmitted to another optical node located downstream.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: April 21, 2015
    Assignee: Fujitsu Limited
    Inventors: Koji Biwa, Kosuke Komaki
  • Patent number: 9008516
    Abstract: A method, an apparatus, and a system for transmitting information in a passive optical network are provided. The method mainly includes: obtaining OAM information that an RE device needs to report to an OLT device, performing modulation processing, according to the OAM information, on a downlink optical signal sent by the OLT device, and returning the downlink optical signal after the modulation processing to the OLT device; or, obtaining OAM information that an OLT device needs to deliver to an RE device, performing modulation processing, according to the OAM information, on a downlink optical signal sent by the OLT device to the RE device, and sending the downlink optical signal after the modulation processing to the RE device.
    Type: Grant
    Filed: January 23, 2012
    Date of Patent: April 14, 2015
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Kun Li, Shiyi Cao, Jianlin Zhou, Min Ye
  • Patent number: 9008130
    Abstract: A remote enclosure houses multiple subsystems. A first subsystem is coupled to a central office over a high-speed communication channel such as an OC-3 channel. The first subsystem extracts a downstream message from a first embedded operations channel included in the high-speed communication channel. The first subsystem also, when the downstream message is targeted to a first unit included in the first subsystem, forwards the message to a unit that processes the message for the first unit. When the message is not targeted to any unit included in the first subsystem, the first subsystem forwards the downstream message to another subsystem housed within the remote enclosure via a second embedded operations channel included in a second communication channel. The second subsystem is subtended from the first subsystem and is connected thereto by the second communication channel.
    Type: Grant
    Filed: August 15, 2003
    Date of Patent: April 14, 2015
    Assignee: ADC DSL Systems, Inc.
    Inventors: Donald J. Glaser, Carl E. Gabrjelson, Jr., Ashraf Nisar
  • Patent number: 8958692
    Abstract: An optical transmission system includes a first node and a second node, the first node includes a first optical amplifier which outputs a signal to the second node through a first transmission line and a first monitoring unit, the second node includes a monitor which monitors a signal from the first transmission line, a second optical amplifier which outputs a signal to the first node through a second transmission line and a second monitoring unit, upon detecting disconnection from the first transmission line, the second monitoring unit transmits a notification for making power of the first optical amplifier reduced, upon receipt of the notification, the first monitoring unit reduces power of the first optical amplifier, and transmits a completion notification to the second monitoring unit, and upon not receiving the completion notification even after expiration of an allowed time, the second monitoring unit reduces power of the second optical amplifier.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: February 17, 2015
    Assignee: NEC Corporation
    Inventor: Yutaka Yano
  • Patent number: 8938165
    Abstract: An optical transmission device according to the present invention comprises: a Raman amplification means; a main signal light sending means which sends first main signal light; a communication interruption detection light monitoring means which sends a first signal if it cannot detect communication interruption detection light; a main signal light monitoring means which sends a second signal if it cannot detect second main signal light; a light monitoring signal analysis means which sends a result of its analysis of a light monitoring signal as a third signal in a predetermined period of time; and a control means which makes the Raman amplification means suspend the generation of the excitation light, if it cannot receive the third signal even after the elapse of the predetermined period of time in the state it has received the first signal and has not received the second signal, and stops sending of the first main signal light from the main signal light sending means when receiving the second signal further.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: January 20, 2015
    Assignee: NEC Corporation
    Inventor: Noboru Iijima
  • Patent number: 8934775
    Abstract: A system for signaling between elements in an undersea optical communication system including a cable signal generator. The signal generator includes line current modulation circuitry configured to impart modulation in line current provided on a power conductor of the transmission cable. A method of signaling between elements in an undersea optical communication system includes modulating a line current through an element and detecting the modulated current.
    Type: Grant
    Filed: July 23, 2008
    Date of Patent: January 13, 2015
    Assignee: Tyco Electronics Subsea Communications LLC
    Inventor: Stuart M. Abbott
  • Patent number: 8837950
    Abstract: Embodiments of the present invention include systems and methods for accessing the digital diagnostic data and controller data of a remote transceiver module via the diagnostic port of a local transceiver. The invention involves modulating high-speed data and out-of-band data as a double modulated signal, wherein the out-of-band data includes the remote transceiver controller and digital diagnostic data, which is subsequently accessible by an external user device from the diagnostic port of the local transceiver.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: September 16, 2014
    Assignee: Finisar Corporation
    Inventor: Lucy G. Hosking
  • Patent number: 8805194
    Abstract: An optical transmission device includes a signal generator configured to generate a first signal corresponding to an amount of residual chromatic dispersion that occurs in a light signal transmitted from the optical transmission device to a downstream device, and a superimposer configured to superimpose the first signal on the light signal transmitted from the optical transmission device and transmit the light signal superimposed by the first signal to the downstream device.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: August 12, 2014
    Assignee: Fujitsu Limited
    Inventor: Takashi Toyomaki
  • Patent number: 8705978
    Abstract: An apparatus comprising one or more optical amplifiers coupled to an optical link and configured to amplify a plurality of Wavelength Division Multiplexing (WDM) channels that are transmitted at a plurality of wavelengths on the optical link, and a processor coupled to the optical link and configured to add, delete, or both a plurality of WDM channels in the optical link based on an allowed power ratio indication for the WDM channels, wherein the allowed power ratio indication is calculated based on a plurality of gain change representations for the WDM channels at a plurality of power ratios and on a link budget requirement for the optical link.
    Type: Grant
    Filed: June 20, 2011
    Date of Patent: April 22, 2014
    Assignee: Futurewei Technologies, Inc.
    Inventors: Zhiping Jiang, Jian Zhong
  • Patent number: 8655187
    Abstract: A data center for executing a data processing application includes processing units, sub-units or servers. Each of the processing units, sub-units or servers can execute a part or all of the data processing application. The processing units, sub-units or servers are electrical disjoint with respect to data communications, but can communicate with each other over free space optical links.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: February 18, 2014
    Assignee: Invention Science Fund I
    Inventors: Howard Lee Davidson, James R. Hamilton, Roderick A. Hyde, Arne Josefsberg, Edward K.Y. Jung, Jordin T. Kare, Robert W. Lord, Kenneth Lustig, William Henry Mangione-Smith, Michael Manos, Craig J. Mundie, Nathan P. Myhrvold, Richard F. Rashid, Burton Smith, Clarence T. Tegreene, Robert V. Welland, Charles Whitmer, Lowell L. Wood, Jr.
  • Patent number: 8620160
    Abstract: An optical transmission apparatus includes a reception part for receiving a wavelength division multiplexed (WDM) signal reached via optical amplifiers; a measuring part for measuring an optical power level of each wavelength of the WDM signal received by the reception part; a determination part for determining whether an amount of tilt of the WDM signal calculated based on measurement results of the measuring part is suitable or not; an operation part for calculating the tilt correction amount to be applied to tilt correction processing performed by the optical amplifiers if the amount of tilt of the WDM signal is not suitable; and a notification part for notifying the optical amplifiers of the tilt correction amount.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: December 31, 2013
    Assignee: Fujitsu Limited
    Inventor: Miki Onaka
  • Patent number: 8615172
    Abstract: A method for arranging relay stations in an optical transmission system including relay stations arranged so that optical signals at a first transmission speed can be transmitted from a transmission end to a reception end, includes: judging whether a transmission of optical signals at a second transmission speed different from the first transmission speed in a section connecting arbitrary two of the relay stations where a regenerative repeater station capable of regenerating optical signals can be arranged is possible; determining a combination of sections judged to be capable of performing transmission that enables a transmission of optical signals from the transmission end to the reception end; and making both ends of respective sections of the determined combination be the relay stations where the regenerative repeater station is arranged, wherein the judging includes a judgment condition which is satisfied in a section including sections but unsatisfied in one of the sections.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: December 24, 2013
    Assignee: Fujitsu Limited
    Inventor: Takuya Miyashita
  • Patent number: 8606115
    Abstract: An optical transmission apparatus is provided with an optical filter on a transmission line between a reception end of a transmission line and an OSC receiver. The optical filter has transmission characteristics such as to pass main signal light and optical supervisory channel light (OSC light), and to cut off noise light contained in at least one end portion band on a short wavelength side and a long wavelength side of an OSC transmission band used for reception of OSC light. By such a configuration, even in a case where the OSC light is Raman amplified and transmitted, the influence of noise light due to Raman amplification can be reduced, and OSC light can be received reliably, enabling high dependability to be realized.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: December 10, 2013
    Assignee: Fujitsu Limited
    Inventor: Miki Onaka
  • Patent number: 8554081
    Abstract: An optical add/drop multiplexer (OADM) and system incorporating the same for maintaining loading of WDM channels with loading signals or information signals when signals are added or dropped. The OADM may include reconfigurable band pass filters having a transmittance characteristic controllable using a command signal. Selective filtering of loading signals and/or information signals received from branch and trunk paths allows an output WDM signal including information signals on utilized channels and loading signals on all unutilized channels.
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: October 8, 2013
    Assignee: Tyco Electronics Subsea Communications, LLC
    Inventors: Dmitriy I. Kovsh, Ekaterina A. Golovchenko, Stuart M. Abbott
  • Patent number: 8548321
    Abstract: In an optical transmission apparatus, a unit includes a first connection section, a second connection section, a branching section, a first detection section, and a second detection section. The first connection section connects to a first component. The second connection section connects to a second component. The branching section is disposed at a preceding stage of the second connection section and outputs signal light to the first component through the first connection section. The first detection section determines whether the first component receives the signal light output from the branching section. The second detection section is disposed at a subsequent stage of the second connection section and detects the signal light.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: October 1, 2013
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Iizuka, Takeshi Sakamoto
  • Publication number: 20130129356
    Abstract: An optical communication system includes an optical-signal transmission unit transmitting an existing optical signal and a low-rate-signal superimposition unit superimposing a low-rate signal on the existing optical signal by intensity modulation. It further includes: a low-rate-signal extraction unit that extracts the low-rate signal from the existing optical signal on which the low-rate signal is superimposed and converts the extracted low-rate signal into a low-rate electric signal; an add-on optical-signal transmission unit that transmits an add-on optical signal; a low-rate-signal superimposition unit that superimposes a low-rate signal on the add-on optical signal by the intensity modulation based on the low-rate electric signal; and a repeater that repeats the add-on optical signal on which the low-rate signal is superimposed, to a transmission destination.
    Type: Application
    Filed: September 3, 2010
    Publication date: May 23, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Toshiyuki Tokura, Kazuyuki Ishida, Takashi Mizuochi
  • Patent number: 8433190
    Abstract: An amplifier node, in an optical network, includes a first switch connected to a working path from which network traffic is received; a second switch connected to the working path to which the network traffic is transmitted; and two amplifiers that interconnect the first switch and the second switch, where the network traffic travels from the first switch to the second switch via a first amplifier. The amplifier node also includes a controller to receive an instruction to switch the network traffic from the first amplifier to a second amplifier that enables the first amplifier to be repaired; send, to the first switch and the second switch, another instruction to switch the network traffic from the first amplifier to the second amplifier; receive an indication that the network traffic is traveling via the second amplifier; and send a notification that the first amplifier can be repaired based on the indication.
    Type: Grant
    Filed: August 9, 2010
    Date of Patent: April 30, 2013
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Glenn A. Wellbrock, Tiejun J. Xia
  • Patent number: 8428462
    Abstract: A device may include a component, a first switch, a repeater, and a second switch. The component may configure optical paths between ports. The component may comprise a first pair of optical ports connected to a first pair of optical fibers, and a second pair of optical ports connected to a second pair of optical fibers. The first switch may be configured to output one of two optical signals received by the first pair of optical ports from the first pair of optical fibers. The repeater may reshape or amplify the outputted optical signal. The second switch may be configured to direct the reshaped or amplified signal to one of the second pair of optical ports.
    Type: Grant
    Filed: June 18, 2009
    Date of Patent: April 23, 2013
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Glenn A. Wellbrock, Tiejun J. Xia
  • Patent number: 8417114
    Abstract: Systems, methods, and devices are disclosed for monitoring optical communications between a managed location and a remote location. In particular, an optical signal is transmitted over an optical fiber and passed-through a test device. A portion of the optical signal is filtered from the original optical signal and passed to a monitoring unit. The monitoring unit may instruct one or more switches in the test device to loop the optical signal back toward the managed location. Subsequently, testing and monitoring may be performed at the managed location. The device may provide a test output or may transmit the information to the managed location.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: April 9, 2013
    Assignee: Level 3 Communications, LLC
    Inventors: Jeffrey Kendall Storey, John F. Waters, Jr., Andrew Dugan, Salvador Paredes, Gary Ratterree
  • Patent number: 8355631
    Abstract: A system for transmitting a plurality of data channels and an optical service channel through an optical fiber link of a Wavelength Division Multiplexed (WDM) optical communications system. The system comprises a first transmitter at a first end of the optical fiber link, for transmitting the data channels as a wavelength division multiplexed optical signal through the optical fiber link in a first direction. A second transmitter is connected at a second end of the optical fiber link, for transmitting the optical service channel through the optical fiber link in a second direction opposite to the first direction.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: January 15, 2013
    Assignee: Ciena Corporation
    Inventors: Maurice O'Sullivan, Jamie Gaudette, Roger Carroll
  • Patent number: 8275269
    Abstract: The distributed Raman amplifier monitors an OSNR of each channel in a WDM light which has been propagated through a transmission path to be Raman amplified, and thereafter, is amplified by an optical amplifier in an optical repeating node; judges whether a monitor value of the OSNR is larger or smaller than a previously set target value thereof; and feedback controls a driving state of a pumping light source which supplies a Raman pumping light to the transmission path, based on the judgment result. The optical communication system comprises the above distributed Raman amplifier in each repeating span thereof, and performs a pumping light control of the distributed Raman amplifier corresponding to the repeating span selected based on the OSNR in each distributed Raman amplifier and the monitor result of span loss. As a result, it becomes possible to effectively improve the OSNR of each channel in the WDM light, and also, to reduce the power consumption.
    Type: Grant
    Filed: November 12, 2009
    Date of Patent: September 25, 2012
    Assignee: Fujitsu Limited
    Inventor: Miki Onaka
  • Patent number: 8275268
    Abstract: An optical repeater connected to an optical transmission line between an optical network unit having an optical network unit (ONU) function on the side of a subscriber and an optical line termination (OLT) on the side of a center includes first electrical/optical conversion means connected to a first optical transmission line on the side of the center, a second electrical/optical conversion means connected to a second optical transmission line on the side of the subscriber, and transmission means connected between the first electrical/optical conversion means and the second electrical/optical conversion means to transmit an optical repeater supervisory signal between the optical transmission lines.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: September 25, 2012
    Assignee: Furukawa Electric Co., Ltd
    Inventor: Shimoosako Kazutaka
  • Patent number: 8275010
    Abstract: The pulse light source according to the present invention comprises: a seed pulse generator 1 for outputting an input pulse 10 as a seed pulse; a pulse amplifier 2; and a dispersion compensator 3 for dispersion compensating a light pulse output from the pulse amplifier 2. Moreover, the pulse amplifier 2 comprises a normal dispersion medium (DCF 4) and an amplification medium (EDF 5) that are multistage-connected alternately, for changing the input pulse 10 to a light pulse having a linear chirp and outputting the light pulse. Furthermore, an absolute value of the dispersion of the DCF 4 becomes to be larger than the absolute value of the dispersion of the EDF 5.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: September 25, 2012
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Atsushi Oguri, Shunichi Matsushita
  • Patent number: 8139951
    Abstract: An ultra-long fiber-optic transmission system is configured in accordance with the current telecom standards and particularly advantageous for transmission data at a long distance which may exceed 400 km between adjacent nodes. The disclosed system has at least one intermediate amplifying node provided with a supervisory optical channel (SOC) which carries information between spaced nodes about the multi-wavelength optical signal as well as remote conditions at the optical terminal or regeneration site. The SOC comprises a transponder operative to select the direction in which an optical supervisory signal OSS, carrying information about the fiber break and malfunction of WDM channels, is transmitted along the SOC. The transponder further includes a receiver operative to measure the power of incoming OSS signal, which is indicative of the power of the transmitted and amplified WDM signal, and a Raman controller.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: March 20, 2012
    Inventors: Igor Samartsev, Vladimir Antonenko
  • Patent number: 8126336
    Abstract: An optical repeater connected to an optical transmission line between an optical network unit having an ONU function on the side of a subscriber and an optical line termination (OLT) on the side of a center includes first electrical/optical conversion means connected to a first optical transmission line on the side of the center, a second electrical/optical conversion means connected to a second optical transmission line on the side of the subscriber, and transmission means connected between the first electrical/optical conversion means and the second electrical/optical conversion means to transmit an optical repeater supervisory signal between the optical transmission lines.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: February 28, 2012
    Assignee: Furukawa Electric Co., Ltd.
    Inventor: Shimoosako Kazutaka
  • Patent number: 8121491
    Abstract: A method and apparatus for compensating for channel depletion of a multi-channel signal in an optical link or optical network comprising a chain of optical amplifiers. The method comprises determining channel depletion for each amplifier from the power of the input signal to the optical amplifier and the power of the output signal from the previous amplifier. Each amplifier is then controlled to amplify the signal to a level equal to the nominal (ideal) power plus the calculated channel depletion for that amplifier.
    Type: Grant
    Filed: October 6, 2006
    Date of Patent: February 21, 2012
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Gianmarco Bruno, Fabio Cavaliere
  • Patent number: 8045853
    Abstract: In one embodiment, techniques provide a mechanism for tracking wavelengths in a DWDM network. In particular, embodiments of the present invention also provide for connection tracking using a slowly modulated pilot tone in a DWDM network without dedicated hardware for the generation and the diction of the tone.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: October 25, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Ornan Gerstel, Stefano Piciaccia, Mauro Rudy Casanova, Valerio Viscardi, Gabriele Galimberti
  • Patent number: 8041231
    Abstract: The present invention aims at providing a technique capable of supervising and controlling optical repeaters, without affecting transmission characteristics and wavelength bands of signal lights, by utilizing the Raman effect. To this end, the present invention provides a supervisory controlling system of an optical repeater, in an optical amplifying-and-repeating transmission system for amplifying and repeatingly transmitting signal light propagated through an optical transmission path by the optical repeater, wherein the supervisory control signal light is amplified due to the Raman effect by the signal light acting as excitation light in an optical transmission path (Raman amplifying medium), to thereby supervise and control the optical repeater in accordance with the thus Raman amplified supervisory control signal light.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: October 18, 2011
    Assignee: Fujitsu Limited
    Inventor: Kenji Ohta
  • Patent number: 8036538
    Abstract: A method for laser safety protection in an optical communication system includes: a downstream station detecting whether an identification signal loaded by an upstream station on a main optical channel in a direction from the upstream station to the downstream station, exist on the main optical channel; if the identification signal is not detected, the downstream station executing a scheduled safety protection procedure. Methods for loading an identification signal on a main optical channel in an optical communication system and an optical amplifier of laser safety protection, which implement loading the identification signal by controlling the change of pump light of optical amplifier or the wave motion of signal light of main optical channel, are also provided. The solution makes it possible to reliably detect a fiber failure when RAMAN amplifiers or remotely-pumped amplifiers exist, thereby implementing laser safety protection.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: October 11, 2011
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Hao Wang, Yiquan Lu, Congqi Li
  • Patent number: 8032021
    Abstract: A robust and redundant status link is established by a first multi-channel optoelectronic device with a second multi-channel optoelectronic device in a multi-channel communication link. Transmitter bias currents are effectively modulated with a status link modulation signal representative of status data and subsequently modulated with primary data modulation signals. The resulting signals are transformed into optical signals and transmitted over the link as main communication links combined with a status link. At the second device, the optical signals are received and converted to electrical signals. The receipt of the optical signals creates multiple receiver bias currents, which may be monitored to detect the status link modulation signal. The second device may adjust various operating parameters in response to the information conveyed by the status link.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: October 4, 2011
    Assignee: Finisar Corporation
    Inventors: Christopher R. Cole, Lewis B. Aronson, Darin James Douma
  • Patent number: 7970286
    Abstract: In a wavelength-division multiplexing communications system including a plurality of optical transmission devices having an optical amplifier, downstream optical transmission devices transmit gain wavelength characteristic information of an optical amplifier in each of the downstream optical transmission devices to an upstream optical transmission device. The upstream optical transmission device controls gain wavelength characteristics on the basis of the received gain wavelength characteristic information.
    Type: Grant
    Filed: August 19, 2009
    Date of Patent: June 28, 2011
    Assignee: Fujitsu Limited
    Inventor: Taizo Maeda
  • Patent number: 7822341
    Abstract: In one embodiment, a control method, according to which a cascade of control messages is propagated between nodes of an optically transparent network, with each message being sent from a node to an adjacent downstream node to inform the latter about a control operation scheduled to be performed at the message-sending node and/or an upstream node that impacts an optical communication signal received at that downstream node. The cascade of control messages effectively creates an ad hoc control domain, in which control operations performed at various nodes of that domain can be coordinated to reduce unfavorable interactions between those control operations. By repeatedly propagating appropriate cascades of control messages through the network, control domains can be changed dynamically and adaptively to reflect any changes to the network topology, equipment, and/or traffic distribution.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: October 26, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Robert D. Feldman, Daniel C. Kilper, Thomas A. Skrobala, Christopher A. White, Lili Yu
  • Patent number: 7809279
    Abstract: A system and method using differential loop gain for fault analysis in line monitoring equipment. Differential loop gain data is calculated from loop gain data, and fault analysis is conducted using differential loop gain data, e.g. by comparing the differential loop gain data to predefined fault signatures.
    Type: Grant
    Filed: July 27, 2007
    Date of Patent: October 5, 2010
    Assignee: Tyco Electronics Subsea Communications LLC
    Inventors: Hongbin Zhang, Ralph Brian Jander
  • Patent number: 7783201
    Abstract: An optical repeater device of the present invention comprises: a preamble compensating circuit 53, for taking out a normal data signal from burst signals propagating through a communication transmission path, and for adding a preamble signal before and/or after the data signal. Furthermore, the preamble compensating circuit 53 comprises: a detector circuit 53a, for inputting the burst signal, and for outputting only the normal data signal; a buffer circuit 53b, for storing the data signal output from the detector circuit 53a, and for outputting thereof; a preamble signal generation circuit 53d, for outputting at least one type of the preamble signal; and an data output select circuit 53e, for outputting the data signal at the time of the data signal input from the buffer circuit 53b, and for outputting the preamble signal from the preamble signal generation circuit 53d at any other time thereof.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: August 24, 2010
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Masayuki Miura, Kunio Odaka, Fuyuki Takeuchi
  • Patent number: 7756422
    Abstract: During initial start-up of an optical communication system, an ASE reference span loss is calculated based on transmitting power and received power of ASE light generated by an optical amplifier, and an OSC reference span loss is calculated based on the transmitting power and the received power of OSC light. During normal operation of the optical communication system, a span loss is calculated using the OSC light, and an amount of change in the span loss representing a difference between the span loss and the OSC reference span loss is calculated. A current span loss between a transmitting station and a receiving station is calculated by adding the amount of change in the span loss to the ASE reference span loss.
    Type: Grant
    Filed: August 11, 2006
    Date of Patent: July 13, 2010
    Assignee: Fujitsu Limited
    Inventors: Takeshi Sakamoto, Kosuke Komaki, Yuji Shimada, Takuji Maeda
  • Publication number: 20100142974
    Abstract: The present invention aims at providing a technique capable of supervising and controlling optical repeaters, without affecting transmission characteristics and wavelength bands of signal lights, by utilizing the Raman effect. To this end, the present invention provides a supervisory controlling system of an optical repeater, in an optical amplifying-and-repeating transmission system for amplifying and repeatingly transmitting signal light propagated through an optical transmission path by the optical repeater, wherein the supervisory control signal light is amplified due to the Raman effect by the signal light acting as excitation light in an optical transmission path (Raman amplifying medium), to thereby supervise and control the optical repeater in accordance with the thus Raman amplified supervisory control signal light.
    Type: Application
    Filed: January 19, 2010
    Publication date: June 10, 2010
    Applicant: Fujitsu Limited
    Inventor: Kenji Ohta
  • Patent number: 7725042
    Abstract: An automated optical transport system is provided which provides for automatic discovery of system components, automatic inventory of system components, automatic topology detection, automatic provisioning of channels, and automatic characterization and tuning of system components and fiber. The invention provides automation capability through inclusion of management card capabilities at each station which communicates through a reverse propagating service channel. Dynamic and propagation direction independent segments are provided in conjunction with a token-based scheme to repeatedly tune, update and monitor the transport system.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: May 25, 2010
    Inventors: Marvin Ray Young, Michael H. Eiselt, Daniel Nooner, Jeffrey Pearlman, Michael L. Cooper
  • Patent number: 7715710
    Abstract: Methods and apparatus for optical-power control in an optical network employing wavelength-division multiplexed (WDM) optical-fiber links are devised to circumvent the effect of crosstalk caused by optical-power scattering. Each carrier signal is amplitude-modulated by an identifying tone, with the power of an identifying tone having a predetermined ratio to the power of its carrier signal. A fiber span within an optical-fiber link is tapped at a preferred monitoring point, and the power spectrum of the envelope of the tapped optical signal is measured. To estimate an individual carrier power, a temporary gain is applied and the power of a corresponding tone is measured. To control optical power of each wavelength carrier in several spans in the network, a network controller selects an order of processing the spans of interest, and selects the order of processing of each channel within each span.
    Type: Grant
    Filed: May 29, 2007
    Date of Patent: May 11, 2010
    Assignee: Alcatel Lucent
    Inventors: Ping Wai Wan, Derrick Remedios
  • Patent number: 7711271
    Abstract: The invention provides for optical circulators which redirect light from port to port sequentially in one direction used to separate traffic in a bidirectional optical fiber transmission system. The invention provides for using two optical circulators in each span of bidirectional fiber so that the OSC channel can be transmitted in one direction opposite to the WDM channels. The invention also provides for a gigabit Ethernet path between chassis which is utilized for control traffic and customer traffic. The invention is placed in a non-critical region of the optical spectrum and is independent of all other chassis equipment. The invention also provides the advantage in alternate embodiments of providing the option of a second counter propagating WDM channel being transmitted along with the OSC to provide additional system capacity. The invention also provides the advantage in an alternate embodiment of allowing the OSC to be amplified through a raman source without the need of complete system retrofit.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: May 4, 2010
    Inventors: Michael H. Eiselt, Lara Garrett, Duncan L. MacFarlane, Jeffrey Lloyd Cox
  • Patent number: 7697842
    Abstract: An automated optical transport system is provided which provides for automatic discovery of system components, automatic inventory of system components, automatic topology detection, automatic provisioning of channels, and automatic characterization and tuning of system components and fiber. The invention provides automation capability through inclusion of management card capabilities at each station which communicates through a reverse propagating service channel. Dynamic and propagation direction independent segments are provided in conjunction with a token-based scheme to repeatedly tune, update and monitor the transport system.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: April 13, 2010
    Inventors: Marvin Ray Young, Michael H. Eiselt, Daniel Nooner, Jeffrey Pearlman, Michael L. Cooper
  • Patent number: 7689131
    Abstract: A WDM system includes a plurality of P to P WDM systems connected for wavelength-multiplexing optical signals of a plurality of wavelengths, transmitting them to a transmission path, transmitting wavelength-division multiplexed light while performing amplification by using optical AMP in the transmission path, and subjecting the wavelength-division multiplexed light to wavelength isolation at the reception side. An OSC which is a monitoring control signal such as a normal optical signal is used closely within one P to P WDM system. However, by transmitting and receiving the OSC between a plurality of P to P WDM systems, it is possible to solve a problem at the system rise. Moreover, since accumulative OSNR data is transmitted up to the P to P WDM system of the final stage, it is possible to detect an accurate OSNR value and a leak ASE light quantity at the end side.
    Type: Grant
    Filed: November 11, 2003
    Date of Patent: March 30, 2010
    Assignee: Fujitsu Limited
    Inventors: Kimio Uekama, Takehiro Fujita, Motoyoshi Sekiya
  • Patent number: 7684711
    Abstract: An optical transmission system comprises two optical fibers carrying optical signal traffic between two terminals, and a plurality of optical repeaters coupled to the two fibers each repeater having a permanently connected passive high loss loop back circuit between the two fibers. One terminal includes a transmitter, which launches a pulsed supervisory signal on a dedicated supervisory wavelength into one optical fiber, and a receiver, which detects a portion of the supervisory signal looped back from each repeater in order to identify the existence and location of faults in the transmission system. The pulsed supervisory signal is of sufficiently short duration such that portions of the signal returned from each repeater do not overlap with one another and interference with the counter-propagating traffic is avoided by utilizing a dedicated supervisory wavelength. Each return pulse is integrated sequentially by a single detector and processed by heterodyne reception and synchronous demodulation.
    Type: Grant
    Filed: April 21, 2005
    Date of Patent: March 23, 2010
    Assignee: Xtera Communications, Inc.
    Inventors: Steve Desbruslais, John Ellison, David Powell
  • Patent number: 7676160
    Abstract: The present invention aims at providing a technique capable of supervising and controlling optical repeaters, without affecting transmission characteristics and wavelength bands of signal lights, by utilizing the Raman effect. To this end, the present invention provides a supervisory controlling system of an optical repeater, in an optical amplifying-and-repeating transmission system for amplifying and repeatingly transmitting signal light propagated through an optical transmission path by the optical repeater, wherein the supervisory control signal light is amplified due to the Raman effect by the signal light acting as excitation light in an optical transmission path (Raman amplifying medium), to thereby supervise and control the optical repeater in accordance with the thus Raman amplified supervisory control signal light.
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: March 9, 2010
    Assignee: Fujitsu Limited
    Inventor: Kenji Ohta
  • Patent number: 7657187
    Abstract: An optical transmission apparatus for amplifying and relaying a wavelength-division-multiplexed optical signal includes (1) a variation-detecting unit which detects varying speed of input power of the wavelength-division-multiplexed optical signal and compares the varying speed with a set value, (2) an optical amplifying unit which amplifies the wavelength-division-multiplexed optical signal at a fixed amount of amplification, (3) a variable optical attenuating unit which variably attenuates the wavelength-division-multiplexed optical signal, (4) and a controlling unit which controls attenuation amount of the variable optical attenuating unit in accordance with the varying speed.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: February 2, 2010
    Assignee: NEC Corporation
    Inventor: Katsuhiko Shimizu
  • Patent number: 7630634
    Abstract: A node for managing an optical signal includes a first system optics card for providing channels to be transported over a first optical transport link and receives channels from a second optical transport link. Channels received over the second optical transport link are provided to an optical converter card for transport to a client device, for feedback onto the first optical transport link, or pass through to a second system optics card of the node. The first system optics card is capable of dropping network channels from the second transport link to associated client devices through optical converter cards and add client channels received from optical converter cards to the first transport link. The first system optics card may include one or more express input and output ports to couple with one or more other system optics cards in order to provide multiple degrees of communication capability.
    Type: Grant
    Filed: December 27, 2005
    Date of Patent: December 8, 2009
    Assignee: Tellab Operations, Inc.
    Inventor: Mark E. Boduch
  • Patent number: 7627256
    Abstract: A wavelength division multiplexed optical signal transmission method, a wavelength division multiplexed optical signal transmission system and an optical repeater enabling the number of wavelengths to be detected without error even when optical noise is caused in the optical repeater and such functions as adjustment and monitoring of the level of a wavelength division multiplexed optical signal to be performed properly. An optical repeater processes controlled optical signals of different wavelengths individually based on a control optical signal that contains wavelength number information indicating the total number of wavelengths and the presence or absence of a controlled optical signal with respect to each wavelength. Thus, even when optical noise is caused in the optical repeater, the number of wavelengths can be detected without error and such functions as adjustment and monitoring of the level of a wavelength division multiplexed optical signal can be performed properly.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: December 1, 2009
    Assignee: NEC Corporation
    Inventor: Koichi Tokunaga
  • Patent number: 7606488
    Abstract: In a wavelength-division-multiplexing optical transmission system in which optical-node apparatuses that perform relay transmission of wavelength-division-multiplexed light are located at specified nodes in a main optical transmission path, an optical amplifier switches level control to constant-gain control when there is a notification of a change in the number of multiplexed wavelengths, and then after a specified amount of time restarts level control so that the level becomes a target level that corresponds to the actual number of wavelengths.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: October 20, 2009
    Assignee: Fujitsu Limited
    Inventor: Yasushi Sugaya