Wdm System Patents (Class 398/34)
  • Patent number: 10382126
    Abstract: In some examples, a multi-wavelength power meter may include a first coupler to separate optical signals from an optical line terminal and an optical network terminal to ascertain a reduced percentage of total power related to the optical signals. A second coupler may receive the separated optical signals, combine the separated optical signals, and output the combined optical signals to an optical fiber. A filter may be communicatively connected to the optical fiber to isolate at least one specified wavelength or wavelength range of the combined optical signals. A photodiode may be communicatively connected to the filter for power measurement of the at least one specified wavelength or wavelength range.
    Type: Grant
    Filed: June 29, 2018
    Date of Patent: August 13, 2019
    Assignee: VIAVI SOLUTIONS DEUTSCHALND GMBH
    Inventors: Joachim Loenne, Wolfgang Moench
  • Patent number: 10205520
    Abstract: Embodiments of the present invention relate to method and device for measuring optical signal-to-noise ratio (OSNR). A method for measuring an OSNR of a signal of interest may comprise: obtaining spectrum of the signal of interest, the spectrum including power spectrum density distribution of the signal of interest in a channel bandwidth B; obtaining spectrum of a comparative signal that has the same spectrum characteristics as but different OSNR than the signal of interest, the spectrum including power spectrum density distribution of the comparative signal in the channel bandwidth B; and calculating the OSNR of the signal of interest by using the spectrum of the signal of interest and the spectrum of a comparative signal.
    Type: Grant
    Filed: August 3, 2017
    Date of Patent: February 12, 2019
    Assignee: Accelink Technologies Co., Ltd.
    Inventors: Shuang Chen, Liping Sun, Qianggao Hu, Yan Chen, Hui Xie, Qingyan Yue, Fei Liang, Yin Zhang, Hehui Wu
  • Patent number: 10197749
    Abstract: A BOSA device having an adjustable wavelength in two directions comprises a signal transmitter section and a signal receiver section, wherein the signal transmitter section sequentially includes a laser (1-1), a semiconductor optical amplifier (SOA) (3-1), a splitter (4-1), a data upload and download port (5-1), and a first TEC temperature control module (9-1) to control temperature of the laser (1-1) so as to adjust its output wavelength, and the signal receiver section sequentially includes a filter (7-1), a photo detector (8-1), and a receiving end driving device to change an angle of the filter (7-1) with respect to the optical path so as to make a passing wavelength of the filter adjustable. The first TEC temperature control module (9-1) controls temperature of the laser (1-1), and the receiving end driving device drives the filter (7-1) to change an angle of the filter with respect to the optical path.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: February 5, 2019
    Assignee: Accelink Technologies Co., Ltd.
    Inventors: Yaping Lu, Zhenfeng Xue, Yongan Fu, Liping Sun, Jun Zhang, Lijuan Wang, Wenjuan He
  • Patent number: 10158422
    Abstract: There is provided an apparatus configured to estimate optical transmission performance in a transmission path of an optical signal, the apparatus including a memory, and a processor coupled to the memory and the processor configured to acquire a first index related to a first transmission performance of an optical signal transmitted through a span group between a first node and an n-th node and a second index related to a second transmission performance of an optical signal transmitted through a span or a span group between the first node and an m-th node, wherein n is an integer of 3 or more, and m is the integer satisfying m<n, and estimate a third index related to a third transmission performance of an optical signal to be transmitted through a span between the m-th node and the n-th node, based on the first index and the second index.
    Type: Grant
    Filed: April 18, 2017
    Date of Patent: December 18, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Shoichiro Oda, Masatake Miyabe, Setsuo Yoshida, Yasuhiko Aoki, Toru Katagiri, Goji Nakagawa, Shigeru Ishii, Yutaka Takita
  • Patent number: 10148383
    Abstract: A multiport optical switch is used to controllably select a specific incoming optical signal that is to be processed by an associated optical channel monitor (OCM). The OCM includes a tunable optical filter and photodetector arrangement, and is configured to measure the optical spectrum of the incoming optical signal and extract information associated with the various optical channels forming the incoming optical signal (i.e., power, wavelength, OSNR, etc., per channel in the signal). The OCM also includes a processor that generates a pair of output control signals, a first signal to control the wavelength scanning process of the tunable optical filter and a second signal to control the setting of the multiport optical switch. The second signal may also be used to perform “detuning” of a selected input of the multiport optical switch, providing the ability to adjust the power level of an input signal prior to entering the OCM.
    Type: Grant
    Filed: March 13, 2017
    Date of Patent: December 4, 2018
    Assignee: II-VI INCORPORATED
    Inventor: Michael Cahill
  • Patent number: 10020889
    Abstract: A passive optical network (PON) includes a first optical line terminal (OLT), a second OLT, and an optical network unit (ONU). The first OLT sends an equalization delay change message to the ONU, wherein the equalization delay change message includes an equalization delay, an upstream channel ID and a downstream channel ID corresponding to the equalization delay. The ONU receives the equalization delay change message. When the ONU tunes from the first OLT to the second OLT, the ONU obtains the equalization delay for upstream transmission according to the upstream channel ID and the downstream channel ID.
    Type: Grant
    Filed: March 24, 2016
    Date of Patent: July 10, 2018
    Assignee: FUTUREWEI TECHNOLOGIES, INC.
    Inventors: Xuming Wu, Yuanqiu Luo, Dekun Liu, Jianhe Gao
  • Patent number: 9985727
    Abstract: An optical communication link that includes two nodes interconnected by an optical channel that comprises optical fiber(s), and that is used to communicate an optical signal comprising multiple optical signal wavelengths. The first node provides an optical signal onto the optical channel towards the second node, or receives an optical signal from the optical channel from the second node. A Raman pump provides Raman pump power into the optical fiber of the optical channel to thereby perform Raman amplification of the optical signal in the optical fiber. The second node determines a quality measurement of at least of optical wavelength signals transmitted by the first node to the second node. The second node also transmits information from the quality measurement back to the first node. A controller at the first node controls at least one parameter of the Raman pump in response to this transmitted information.
    Type: Grant
    Filed: April 27, 2015
    Date of Patent: May 29, 2018
    Assignee: Neptune Subsea IP Limited
    Inventors: Wayne S. Pelouch, Stephen Michael Webb, John G. Ellison
  • Patent number: 9967637
    Abstract: A quantum key distribution system is deployed in an optical fiber network transporting classical data traffic. A source of entangled photon pairs is used to generate quantum keys. Classical data traffic is typically transported over channels in the C-band. If a pair of channels for transport of quantum data is available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in the C-band. If a pair of channels for transport of quantum data is not available within the C-band, then the source of entangled photon pairs is tuned to emit in a pair of channels in a combined S-band and L-band. When a periodically-poled lithium niobate waveguide pumped with a laser is used for the source of entangled photon pairs, the output spectral properties are tuned by varying the temperature of the waveguide.
    Type: Grant
    Filed: January 2, 2014
    Date of Patent: May 8, 2018
    Assignee: AT&T INTELLECTUAL PROPERTY I, L.P.
    Inventors: Michael Brodsky, Cristian Antonelli, Jungmi Oh
  • Patent number: 9954636
    Abstract: A node that is colorless, directionless and contentionless includes an add/drop terminal having an add wavelength selective switch (WSS) and a drop WSS. The add and drop WSSs are each configured to selectively direct any subset of the wavelength components received at any of its inputs to a different one of its optical outputs, provided that the wavelength components of optical beams received by any two of the inputs cannot be simultaneously directed to a common one of the outputs. A plurality of transponder ports are each optically coupled to a different output of the drop WSS and a different input of the add WSS.
    Type: Grant
    Filed: November 27, 2015
    Date of Patent: April 24, 2018
    Assignee: Nistica, Inc.
    Inventor: Jefferson L. Wagener
  • Patent number: 9906306
    Abstract: An optical transmission system includes: a first light source configured to output a light wave of a first wavelength among a plurality of wavelengths; a second light source configured to output a light wave of a second wavelength; and a first detection section configured to detect abnormality in the light wave from the first light source, wherein upon detection of abnormality, a multiplexed optical signal including an optical signal of a modulated light wave generated using the light wave from the second light source in place of an optical signal of a modulated light wave generated using the light wave from the first light source is transmitted.
    Type: Grant
    Filed: June 2, 2015
    Date of Patent: February 27, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Takashi Shimizu, Tsuyoshi Yamamoto
  • Patent number: 9860011
    Abstract: Disclosed is a method and an apparatus for selecting a wavelength in a hybrid Passive Optical Network (PON) system. The method of selecting a wavelength by a wavelength selecting apparatus in a hybrid passive optical network system includes: performing synchronization with any one of a plurality of downstream wavelengths; when the synchronization is succeeded, determining whether to select the synchronized downstream wavelength for a registration to an optical line terminal; and when it is determined to select the synchronized downstream wavelength, performing the registration to the optical line terminal through the synchronized downstream wavelength.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: January 2, 2018
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Geun Yong Kim, Hark Yoo, Sung Chang Kim, Dong Soo Lee
  • Patent number: 9851249
    Abstract: A sensor system is disclosed, wherein the sensor system provides output data only when the error between a plurality of measured absorption wavelengths of a gas cell and a plurality of known absorption lines for the gas cell is less than or equal to a user-defined error margin.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: December 26, 2017
    Assignee: Micron Optics, Inc.
    Inventor: Todd Christian Haber
  • Patent number: 9838112
    Abstract: An apparatus and method for providing a differential latency, DL, between an upstream, US, transmission and a downstream, DS, transmission via an optical transmission link (OTL), said apparatus comprising a measurement unit (2) configured to measure the round trip delays, RTD, of at least two measurement signals having different measurement wavelengths; and a processing unit (3) configured to derive an upstream, US, delay of at least one optical signal at an upstream wavelength from the at least two measured round trip delays, RTD, and to derive a downstream, DS, delay of at least one optical signal at a downstream wavelength from the at least two measured round trip delays, RTD, wherein the differential latency, DL, is calculated on the basis of the derived delays, RTD.
    Type: Grant
    Filed: October 30, 2015
    Date of Patent: December 5, 2017
    Assignee: ADVA OPTICAL NETWORKING SE
    Inventor: Klaus Grobe
  • Patent number: 9832083
    Abstract: Embodiments of the present disclosure provide an apparatus and method for detecting channel spacing and a system. The apparatus for detecting channel spacing includes a first estimating unit configured to estimate a frequency offset of a center channel according to a received signal, a second estimating unit configured to estimate a frequency offset of a neighboring channel according to the received signal, and a determining unit configured to determine channel spacing according to the frequency offset of the center channel estimated by the first estimating unit and the frequency offset of the neighboring channel estimated by the second estimating unit. With the embodiments of the present disclosure, estimation accuracy of channel spacing may be ensured, and influence of non-ideal factors on estimation value may be reduced.
    Type: Grant
    Filed: October 7, 2016
    Date of Patent: November 28, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Ying Zhao, Liang Dou, Zhenning Tao
  • Patent number: 9780906
    Abstract: An optical line terminal (OLT) comprising a processor configured to process a first power consumption data associated with a first optical network unit (ONU) for a plurality of wavelength channels in a multiple-wavelength passive optical network (PON), and select a first target wavelength channel from the plurality of wavelength channels based on the first power consumption data in order to reduce power consumption at the first ONU, and a transmitter coupled to the processor and configured to transmit to the first ONU a tuning control message instructing the first ONU to tune to the first target wavelength channel.
    Type: Grant
    Filed: October 2, 2015
    Date of Patent: October 3, 2017
    Assignee: Futurewei Technologies, Inc.
    Inventors: Jianhe Gao, Yuanqiu Luo, Dekun Liu
  • Patent number: 9749077
    Abstract: A method (10) of controlling optical signal power levelling in an optical communication network node configured to apply an optical attenuation, ?, to a pass-through optical signal. The method comprises: a. performing the following steps i. to iii. until an attenuation variation value, ??, is greater than a preselected attenuation variation threshold value (18), ??TH: i. measuring (12) an optical signal power of an optical signal; ii. calculating (14) a difference, ?P, between the measured optical signal power and a target optical signal power; iii. calculating (16) a value for the attenuation variation, ??, to be applied to the optical attenuation taking account of ?P; b. obtaining (20) a current value of the optical attenuation, ?n, and obtaining (22) a new optical attenuation value, ?n+1, in dependence on the current value of the optical attenuation, a current value of the attenuation variation, ??n, and at least an earlier value of the attenuation variation, ??n?1; and c.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: August 29, 2017
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventor: Matteo Costantini
  • Patent number: 9729947
    Abstract: Systems and methods for conveying wavelength tuning information from a pluggable optical transceiver to a host device determining the wavelength tuning information of the pluggable optical transceiver operating in the host device; appending the wavelength tuning information as part of existing data communicated between the pluggable optical transceiver and the host device; and providing the existing data with the wavelength tuning information incorporated therewith to the host device.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: August 8, 2017
    Assignee: Menara Networks, Inc.
    Inventors: Siraj Nour Elahmadi, Qingzhong Cai, Fredrick Muya, Paul Tuok, Salam Elahmadi
  • Patent number: 9722700
    Abstract: A wavelength division multiplexing system and method featuring a wavelength monitor that is configured to receive a portion of a combined signal of wavelength division multiplexing channels and determine the wavelengths of each channel or the guardband between each channel in the combined signal. The wavelength monitor determines if there is excess laser drift for each channel in the combined signal. If excess laser drift is determined, feedback is sent to the transmitter for the signal with excess laser drift and the signal is adjusted to produce a target wavelength. The wavelength monitor may utilize optical intradyning in order to monitor the wavelengths of each channel in the combined signal.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: August 1, 2017
    Assignee: NEC Corporation
    Inventors: Fatih Yaman, Shaoliang Zhang, Ting Wang, Yoshihisa Inada, Takaaki Ogata
  • Patent number: 9692547
    Abstract: In some aspects, an example method may include receiving, at a receiver of a first optoelectronic module, a loss of signal indicator from a second optoelectronic module that is remote from the first optoelectronic module. The method may include iteratively cycling through transmission of optical signals on a plurality of wavelength channels to the second optoelectronic module until the loss of signal indicator terminates in response to receiving the loss of signal indicator. The method may include continuing to transmit the optical signal on a particular one of the plurality of wavelength channels in response to the loss of signal indicator terminating while transmitting an optical signal on the particular one of the plurality of wavelength channels.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: June 27, 2017
    Assignee: FINISAR CORPORATION
    Inventors: Mingshou He, Huade Shu, Jing Li, Bin Ma, Ronghua Jin
  • Patent number: 9680570
    Abstract: A method of monitoring at least one optical wavelength component of a WDM optical signal being routed through a wavelength selective switch (WSS) includes directing an optical wavelength component from a given input port of the WSS to a selected output port with a selected amount of attenuation. A rejected portion of the optical wavelength component giving rise to the selected amount of attenuation is directed to an optical monitor associated with another output port of the WSS. A power level of the optical wavelength component is determined by pre-calibrating a proportionality between the power level of the wavelength component and the power level of the rejected portion that is directed to the optical monitor.
    Type: Grant
    Filed: April 30, 2015
    Date of Patent: June 13, 2017
    Assignee: Nistica, Inc.
    Inventors: Jefferson L. Wagener, Bradford Smith
  • Patent number: 9654212
    Abstract: A communications controller, and corresponding method therein, for wavelength control of a first and second channel. The first and second channels are bidirectional and adjacent to one another in a single fiber in a Dense Wavelength Division Multiplexing (DWDM) based system.
    Type: Grant
    Filed: November 15, 2013
    Date of Patent: May 16, 2017
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Stefan Dahlfort
  • Patent number: 9628174
    Abstract: A multiport optical switch (such as an N×1 switch) is used to controllably select a specific incoming optical signal that is to be processed by an associated optical channel monitor (OCM). The OCM includes a tunable optical filter and photodetector arrangement, and is configured to measure the optical spectrum of the incoming optical signal and extract information associated with the various optical channels (wavelengths) forming the incoming optical signal (i.e., power, wavelength, OSNR and the like for each channel). The OCM also includes a signal processing component that generates a pair of output control signals, a first signal to control the wavelength scanning process of the tunable optical filter and a second signal to control the setting of the multiport optical switch.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: April 18, 2017
    Assignee: II-VI INCORPORATED
    Inventors: Michael Cahill, Christopher S. Koeppen, Glenn Bartolini, Jayesh Jasapara
  • Patent number: 9537575
    Abstract: The present invention as disclosed and described herein, in one aspect thereof, comprises a method for multiple access communications over a communications link involves receiving a plurality of data streams from a plurality of data sources. The plurality of data streams are grouped into a plurality of groups. Orthogonal frequency division multiplexing (OFDM) processing is applied to each of the plurality of groups. Each of the plurality of groups uses a same combination of frequency and time slot combinations in the OFDM processing. A different orthogonal function is applied to each of the OFDM processed groups to uniquely identify each of the OFDM processed group from each other and the orthogonal function processed groups are transmitted over the communications link.
    Type: Grant
    Filed: August 4, 2015
    Date of Patent: January 3, 2017
    Assignee: NXGEN PARTNERS IP, LLC
    Inventors: Solyman Ashrafi, Roger Linquist
  • Patent number: 9484708
    Abstract: A laser module includes a light source device having a first amplifier that outputs first output light, and a second amplifier that outputs second output light, a first drive circuit that supplies the first amplifier with a first drive current, a second drive circuit that supplies the second amplifier with a second drive current. A dither signal is superimposed on one of two drive currents to respectively grasp the characteristics of the two amplifiers.
    Type: Grant
    Filed: October 19, 2015
    Date of Patent: November 1, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Satoshi Kajiya, Tetsuhiro Fukao
  • Patent number: 9438969
    Abstract: Device and method for optically switching a plurality of optical input signals include: receiving the plurality of optical input signals, wherein one or more of the optical input signals represent multiple channels at different channel frequencies; collimating the received plurality of optical input signals; removing noise between the channels by a comb filter; dispersing the collimated optical signals so that signals of different wavelength are separated by different angles; focusing the optical signals separated by different angles on a light switch device having a plurality of micromirrors; and controlling the light switch by a control signal to direct one or more of the optical signals separated by different angles to one or more output fibers for multicasting of the optical input signals.
    Type: Grant
    Filed: July 18, 2014
    Date of Patent: September 6, 2016
    Assignee: RAYTHEON COMPANY
    Inventors: John F. Silny, Gary D. Coleman
  • Publication number: 20150139641
    Abstract: A method that may include receiving a block of signals from a certain wavelength division multiplex (WDM) channel out of a set of WDM channels; analyzing at least a first sub-block of signals of the block of signals to provide analysis results indicative of interferences that affect the first sub-block of signals and result from transmissions over other WDM channels of the set of WDM channels; and mitigating interferences that affect the block of signals in response to the analysis results.
    Type: Application
    Filed: November 13, 2014
    Publication date: May 21, 2015
    Inventors: Meir FEDER, Ronen Dar, Mark Shtaif, Antonio Mecozzi
  • Publication number: 20150139640
    Abstract: In one embodiment, an optical performance monitor (OPM) is configured to monitor a received optical wavelength-division-multiplexed (WDM) signal generated by modulating spectral lines of an optical frequency comb. The OPM is further configured to mix the received optical WDM signal with light of another optical frequency comb having a slightly different tooth spacing to generate a set of beat signals at frequencies representing frequency differences between the spectral lines (such as, at the carrier frequencies) of the optical WDM signal and the spectral lines of said another optical frequency comb. The OPM can further be configured to measure one or more parameters of the received optical WDM signal based on the characteristics of the generated beat signals and provide the resulting OPM data to a system controller for maintaining favorable signal-transport conditions within the system.
    Type: Application
    Filed: November 19, 2013
    Publication date: May 21, 2015
    Applicant: ALCATEL-LUCENT USA INC.
    Inventors: Robert M. Jopson, Alan H. Gnauck
  • Patent number: 9037002
    Abstract: A pre-emphasis control method includes calculating an average value of transmission characteristics based on transmission characteristics of a plurality of light beams received by a receiver, and determining that, among signals of the plurality of light beams, a wavelength with a deviation from the average value is a wavelength at which control is to be performed, determining that the wavelength at which control is to be performed and a wavelength adjacent thereto are a group of wavelengths at which control is to be performed, obtaining an average of transmission characteristics of the group of wavelengths at which control is to be performed, and based on a difference between averaged transmission characteristics and respective transmission characteristics of the group of wavelengths at which control is to be performed, changing a light intensity output from each transmitter that transmits a group of wavelengths at which control is to be performed.
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: May 19, 2015
    Assignee: FUJITSU LIMITED
    Inventors: Jyunji Tanaka, Shinichi Kaneko, Takeo Osaka
  • Patent number: 9031404
    Abstract: A method of monitoring a WDM optical signal is provided. The method includes: receiving a WDM optical signal having a plurality of channels; detecting the optical signal after filtering the WDM optical signal with a tunable filter; and reconfiguring at least the center wavelength and bandwidth of the tunable filter optical transfer function to determine a signal performance parameter of the WDM optical signal.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: May 12, 2015
    Assignee: Nistica, Inc.
    Inventors: Jefferson L. Wagener, Thomas Andrew Strasser
  • Publication number: 20150125145
    Abstract: An optical transmission system includes: a first optical transmission device configured to perform bidirectional optical transmission with a second optical transmission device via an optical transmission line, wherein the first optical transmission device includes a transmitted light power adjusting section configured to transmit, to the second optical transmission device, a first light power which is set based on a measurement result, the second transmission device measuring a fluctuating light power transmitted from the first transmission device and informing the first transmission device of the measurement result.
    Type: Application
    Filed: September 10, 2014
    Publication date: May 7, 2015
    Applicant: FUJITSU LIMITED
    Inventor: Tomoaki TAKEYAMA
  • Patent number: 9008509
    Abstract: A system, a device, and a method include a network interface device that measures optical power of a passive optical device; generates optical power data, and stores the optical power data. The system, the device, and the method, also includes generating alarms based on the optical power data and communication with remote network interface devices via the passive optical device.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: April 14, 2015
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Michael B. Freiberger, Evan L. Klassen
  • Publication number: 20150093108
    Abstract: In general, the 1G-EPON standard specifies its upstream waveband broadly to allow for low cost lasers to be used to transmit upstream. Often, however, the lasers actually used by many 1G-ONUs to transmit upstream only occupy a narrow waveband that does not overlap with the upstream waveband specified by the 10G-EPON standard. The present disclosure is directed to systems and methods that exploit this fact to efficiently provide for the coexistence of 10G-EPON and 1G-EPON over the same set of optical fibers in the upstream direction.
    Type: Application
    Filed: September 30, 2013
    Publication date: April 2, 2015
    Inventors: Ryan Edgar HIRTH, Glen Kramer
  • Patent number: 8989574
    Abstract: A WDM signal light monitoring device includes a first monitor for monitoring input-side WDM main signal light and output-side WDM main signal light for each wavelength; and a second monitor for monitoring the first monitor by comparing a monitoring result received from an upstream WDM transmission device with a monitoring result of the first monitor, wherein the monitoring result of the first monitor is transmitted to a downstream WDM transmission device in the system.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: March 24, 2015
    Assignee: NEC Corporation
    Inventor: Baku Kikuchi
  • Publication number: 20150063798
    Abstract: An optical transmission device includes: a reception unit configured to receive a plurality of light beams and wavelength allocation information of optical signals included in each of the light beams; a demultiplexing unit configured to demultiplex the plurality of light beams received; a plurality of switches configured to switch between transmitting or blocking with respect to the demultiplexed plurality of light beams; a multiplexing unit configured to multiplex light beams transmitted from the plurality of switches; a monitoring unit configured to monitor an intensity of the multiplexed light beams; and a controller configured to, based on the wavelength allocation information, obtain a combination of the light beams not including the optical signals having overlapping wavelengths, and control the plurality of switches in accordance with the combination.
    Type: Application
    Filed: August 1, 2014
    Publication date: March 5, 2015
    Applicant: FUJITSU LIMITED
    Inventors: Akihiro Mukai, Takaaki Itose, Hiroki Takaki, Ichiro Nakajima, Yoshinobu Matsukawa
  • Patent number: 8971704
    Abstract: An optical network (1) comprising an optical network element (10) comprising a first optical transmitter (14), a first controller (16), a first optical receiver and a second optical receiver and a second optical network element (12). There is provided a transmission path (30) between said first optical network element and said second optical network element. Said first optical transmitter is arranged to generate and transmit a first optical signal. Said first controller is arranged to control said first optical transmitter to generate and transmit said first optical signal at a wavelength selected from a predetermined plurality of wavelengths. Said first optical receiver is arranged to detect a backscatter portion of said first optical signal returned to said first optical network element along said transmission path by distributing scattering.
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: March 3, 2015
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Fabio Cavaliere, Luca Giorgi, Renato Grosso, Ernesto Ciaramella
  • Publication number: 20150050016
    Abstract: An apparatus determines, in response to demands for traffic between nodes in a network transmitting wavelength-multiplexed optical-signals, routes each providing connection between nodes, and estimates, for each link, communication-channels to be established, based on a wavelength-constraint condition that the number of communication-channels to be established be not greater than a first upper-limit for available optical-signal wavelengths. The apparatus assigns wavelengths to the communication-channels, based on a system-constraint condition that the number of optical-signals having an identical wavelength and redundantly usable be not greater than a second upper-limit for available transmission-systems. The apparatus determines a target-number of wavelengths for reducing a required number of transmission-systems.
    Type: Application
    Filed: June 25, 2014
    Publication date: February 19, 2015
    Inventors: Yutaka Takita, Kazuyuki Tajima, Tomohiro Hashiguchi
  • Publication number: 20150043908
    Abstract: A test apparatus and method for testing passive optical networks is provided. The test apparatus includes an optical circuit having an optical coupler for splitting off a portion of optical traffic. During testing of a passive optical network, the optical circuit is coupled into an optical path of the passive optical network. A bit stream corresponding to an activating procedure is captured and analyzed to extract identification information of the module that sent the bit stream.
    Type: Application
    Filed: August 6, 2014
    Publication date: February 12, 2015
    Inventor: Dominik PRAUSE
  • Patent number: 8948597
    Abstract: Based on the demand information etc., an accommodation designing problem and an assignment problem are solved in a conventional method to design a network. It is confirmed whether or not a restriction on the number of wavelengths for each link is observed. When there are links exceeding the restriction of the number of wavelengths, the number of available wavelengths is subtracted from the first link having the largest number of excess wavelengths and the second link farthest from the first link in the links, and the result is set as a wavelength number limited value, thereby performing a network designing process again.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: February 3, 2015
    Assignee: Fujitsu Limited
    Inventors: Kazuyuki Tajima, Tomohiro Hashiguchi, Yutaka Takita
  • Patent number: 8942558
    Abstract: Due to demand for more network bandwidth, a need for multi-user optical network topologies has, and will continue to, increase. A method or corresponding apparatus in embodiments of the present invention provide for an availability determination tool for determining and displaying wavelength and subrate availabilities within a network. Benefits of embodiments of a tool include allowing a user to identify the availability and capacity of any wavelength on any network, via an interactive graphical user interface, such as by using three-dimensional representations. In one embodiment, the disclosed availability determination tool allows users to locate and view any combination of available wavelengths between nodes in an optical network topology, and generate graphical and tabular reports of the availability in order to maintain an efficient and organized method or apparatus for determining and controlling wavelengths in a network.
    Type: Grant
    Filed: May 15, 2013
    Date of Patent: January 27, 2015
    Assignee: Tellabs Operations, Inc.
    Inventors: David W. Jenkins, Ramasubramanian Anand, Hector Ayala, Dion Kwun Kit Leung, Kenneth M. Fisher
  • Patent number: 8942557
    Abstract: Methods and systems are disclosed including receiving, by circuitry of a node conforming to GMPLS protocol, a signal comprising at least one of an optical signal attribute indicative of parameters of a super-channel, the super-channel including a plurality of optical carriers, each of which having a corresponding one of a plurality of wavelengths and being modulated to carry a corresponding one of a plurality of data streams, the super-channel being provisioned in the optical network as one optical channel, wherein the optical signal attribute is one of: quantity of wavelengths of the super-channel, wavelength center frequency of the super-channel, wavelength modulation of the super-channel, wavelength baudrate of the super-channel, and wavelength FEC type of the super-channel. The node further receiving information indicative of frequency slices in use by the super-channel and calculating, using algorithms conforming to CSPF-TE protocol, a path of a second super-channel.
    Type: Grant
    Filed: June 28, 2012
    Date of Patent: January 27, 2015
    Assignee: Infinera Corporation
    Inventors: Iftekhar Hussain, Michael Francis Van Leeuwen, Marco E. Sosa, Vinayak Dangui, Abinder Dhillon
  • Publication number: 20150023659
    Abstract: A digital signal processor (DSP) may receive samples of a signal from an analog-to-digital converter (ADC); convert the samples from a time domain to a frequency domain; determine a clock phase error of the samples while in the frequency domain; and provide a voltage corresponding to the clock phase error. The voltage may be provided to reduce timing errors associated with the samples.
    Type: Application
    Filed: September 30, 2013
    Publication date: January 22, 2015
    Applicant: Infinera Corporation
    Inventors: Han H. Sun, Kuang-Tsan Wu
  • Publication number: 20150016818
    Abstract: An optical transmission system includes: a plurality of optical transmission devices each including: an adjustment unit to adjust optical power of channels in the WDM optical signal; and a controller to control the adjustment unit based on an adjustment amount, and a management device including: a converter to convert an evaluation value for evaluating quality of service provided by using the channels in the WDM optical signal into a threshold value of transmission quality to be satisfied by the channels; and a determination unit to calculate the transmission quality of the channels based on monitoring information of the channels in the WDM optical signal adjusted by the adjusting unit of at least one of the plurality of optical transmission devices and to determine the adjustment amount to be set for the optical transmission device so that the calculated transmission quality of the channels satisfy the threshold value.
    Type: Application
    Filed: June 25, 2014
    Publication date: January 15, 2015
    Applicant: FUJITSU LIMITED
    Inventors: Taizo MAEDA, Takuya MIYASHITA
  • Patent number: 8934769
    Abstract: An optical transport network signal (OTM) comprising at least one optical channel is received at a first network equipment. The optical transport network signal (OTM) is processed to extract optical data units (ODUk) for each optical channel (OCh). There is detection for defects during the processing. The optical data units are retransmitted within optical transport units (OTUk) towards a second network equipment. When a defect has been detected, the retransmitting comprises inserting an optical channel transport unit alarm indication signal (OTUk-AIS) in an optical channel transport unit (OTUk) containing optical channel data units (ODUk) that are affected by the detected defect.
    Type: Grant
    Filed: November 25, 2009
    Date of Patent: January 13, 2015
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Orazio Toscano, Sergio Lanzone
  • Publication number: 20150010302
    Abstract: An apparatus for measuring optical power including a first multiplexer/demultiplexer to split/combine an optical signal including a first wavelength and second wavelength; a second multiplexer/demultiplexer to split/combine an optical signal including the first wavelength and the second wavelength; a first tap photodetector coupled to the first and second multiplexer/demultiplexers and to a first measurement device; and a second tap photodetector coupled to the first and second multiplexer/demultiplexers and to a second measurement device.
    Type: Application
    Filed: February 6, 2013
    Publication date: January 8, 2015
    Applicant: AFL TELECOMMUNICATIONS LLC
    Inventors: Dale Eddy, Scott Prescott
  • Patent number: 8923694
    Abstract: An optical receiving device includes: an optical amplifier configured to amplify a wavelength multiplexed optical signal; a demultiplexer configured to demultiplex the amplified wavelength multiplexed signal into optical signals of a plurality of wavelengths; optical receivers configured to regenerate the demultiplexed optical signals; error correction units configured to correct a bit error in the regenerated optical signals; and main control unit. The control unit adjusts RXDTV of the optical receiver for receiving optical signals of a given wavelength to the optimal value in the state where the gain of the optical amplifier is lowered from that of a normal operation such that the occurrence of bit errors in the optical signals of the other wavelengths does not exceed the correction capability of the error correction unit.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: December 30, 2014
    Assignees: Fujitsu Telecom Networks Limited, Fujitsu Limited
    Inventors: Toshiki Honda, Takehiro Fujita, Yasushi Sugaya
  • Publication number: 20140376909
    Abstract: Described herein is an optical channel monitor (1) including one or more input optical ports (3) for receiving an input optical signal (5) including a plurality of optical channels. A first monitoring module (7) is configured to selectively scan a predetermined spectral region of the optical signal including at least one optical channel for low resolution monitoring. A second monitoring module (11) is configured to simultaneously scan a subregion within the predetermined spectral region for high resolution monitoring.
    Type: Application
    Filed: June 17, 2014
    Publication date: December 25, 2014
    Applicant: FINISAR CORPORATION
    Inventors: Steven James Frisken, Simon Poole, Dmitri Abakoumov
  • Patent number: 8917987
    Abstract: A method for detecting branch fibers is provided, which includes: sending test signals to a plurality of branch fibers, where the test signals are added at ports of the optical splitting module with identification information for identifying branch fibers connected to the ports and receiving a reflection signal added with the identification information of a detected branch fiber, identifying the detected branch fiber corresponding to the reflection signal through detecting the identification information added to the reflection information, and obtaining channel characteristics of the detected branch fiber according to the reflection signal. Further, a system and an apparatus for detecting branch fibers are provided.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: December 23, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Yunsheng Wen, Jun Zhao, Shijun Wang, Xiaolei Shan, Bo Wang
  • Patent number: 8917988
    Abstract: A system to provide carrier frequency control in an optical network includes a first network element monitoring performance information and a second network element coupled to the first network element by the optical network. The second network element receives performance information from the first network element using an administration channel bandwidth, and modifies a carrier frequency associated with the second network element based on the performance information such that the carrier frequency is aligned to a center of a signal channel bandwidth. A method of providing carrier frequency control includes transmitting performance information by the first network element to the second network element using an administration channel bandwidth, and modifying the carrier frequency by the second network element based on the performance information such that the carrier frequency is aligned to the center of the signal channel bandwidth.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: December 23, 2014
    Assignee: AT&T Intellectual Property I, L.P.
    Inventor: Xiang Zhou
  • Publication number: 20140355980
    Abstract: An optical communication apparatus includes a variable resistor unit, a measurement unit, and a control unit. The variable resistor unit is arranged at a pre-stage of an electrical/optical conversion unit, which converts an electrical signal obtained by converting an input packet to an optical signal having a waveform corresponding to a potential difference between a positive phase component and a negative phase component of the electrical signal by using the potential difference. The variable resistor unit provides a resistor that varies a midpoint of potential of the positive phase component or the negative phase component. The measurement unit measures a ratio of a presence period, which is a period where the input packet is present, to a sum of the presence period and a non-presence period. The control unit controls a value of the resistor provided to the positive phase component or the negative phase component based on the ratio.
    Type: Application
    Filed: June 3, 2014
    Publication date: December 4, 2014
    Applicants: FUJITSU LIMITED, FUJITSU TELECOM NETWORKS LIMITED
    Inventors: Yuichiro Sakane, Koji Matsunaga, Yasuo Tanaka, Tatsuya Toyozumi, Koji Bato, Wataru Kawasaki, Tatsuhiko Saito
  • Publication number: 20140348502
    Abstract: An optical signal monitor circuit is an optical signal monitor circuit including a PD which directly detects an optical signal and converts the optical signal into a photocurrent, a PD which detects the optical signal and converts the optical signal into a photocurrent, a resistance element which converts these photocurrents into voltages, and an operational amplifier which outputs the voltages generated by the resistance element, wherein the optical signal monitor circuit further includes a switching control circuit which switches a connection between the PDs and the resistance element, and a calculation circuit which acquires the output of the operational amplifier as a digital signal, the switching control circuit controls switching to flow the two photocurrents into the resistance element at individual timings and flow the two photocurrents into the resistance element at the same timing, and the calculation circuit calculates a corrected digital signal by subtracting the obtained digital signal.
    Type: Application
    Filed: May 22, 2014
    Publication date: November 27, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Tomoko Miura, Keiji Tanaka