Fiber Characteristic Patents (Class 398/28)
  • Patent number: 9778138
    Abstract: A light physical constant measurement method includes: virtually dividing an optical transmission medium along a propagation direction to set a plurality of first segments; and estimating light physical constants of the plurality of first segments based on the result of a first propagation simulation that uses a model in which an input optical signal of each of the plurality of intensities propagates sequentially through the plurality of first segments, and in the estimating of light physical constants of the plurality of first segments, the light physical constants of the plurality of first segments are searched for using an evaluation function of evaluating a difference between a measured power spectrum of an output optical signal and a power spectrum of the output optical signal obtained as a result of the first propagation simulation, to estimate the light physical constants of the plurality of first segments.
    Type: Grant
    Filed: December 24, 2013
    Date of Patent: October 3, 2017
    Assignee: OSAKA UNIVERSITY
    Inventors: Tsuyoshi Konishi, Koji Takahashi, Kentaro Kawanishi
  • Patent number: 9414448
    Abstract: A self-contained calibration method for improving stability of an optical source in an optical network test instrument includes performing a temperature sweep test of the optical source. Optical output power of the optical source is periodically measured. A temperature correcting value is generated based on the measured optical output power. The optical output power of the optical source is adjusted by applying the temperature correcting value to obtain a substantially constant optical output power of the optical source.
    Type: Grant
    Filed: December 31, 2013
    Date of Patent: August 9, 2016
    Assignee: Fluke Corporation
    Inventors: Jackson Salling, J. David Schell
  • Patent number: 9225455
    Abstract: Systems, devices and techniques for processing an optical signal transmitted from a source over a transmission medium having a length L and performing compensation of non-linear distortions include formulating the compensation as a digital back propagation algorithm by logically dividing the length L into N steps and compensating non-linear distortions for each step as a function of an attenuation adjusting constant parameter that can be selected from a range between 0.3 and 0.7.
    Type: Grant
    Filed: January 14, 2014
    Date of Patent: December 29, 2015
    Assignee: ZTE (USA) Inc.
    Inventors: Jianjun Yu, Junwen Zhang
  • Patent number: 9197322
    Abstract: A method and system for generating an optical channel signal for transmission through an optical fiber link of an optical communications system. A digital filter processes an input data signal using a compensation function and a shaping function to generate a pair of multi-bit sample streams representing a target optical E-field envelope of the optical channel signal. A modulator modulates an optical carrier light using the pair of multi-bit sample streams to generate the optical channel signal. The compensation function is designed to at least partially compensate impairments of the optical fiber link. The predetermined shaping function is designed to modify a baseband spectrum of the target optical E-field envelope.
    Type: Grant
    Filed: February 5, 2014
    Date of Patent: November 24, 2015
    Assignee: CIENA CORPORATION
    Inventors: David W. Boertjes, Kevin MacNeill, Jamie Gaudette
  • Patent number: 9163958
    Abstract: Disclosed are methods and devices for distributed sensing of a measurable parameter employing stimulated Brillouin scattering in an optical fiber. A frequency-modulated or phase-modulated light wave is transmitted into the optical fiber. A scattered light wave in the optical fiber is monitored for sensing a measurable parameter. In some embodiments, the calculating step may include calculating a distance of a sensed location along the optical fiber using the monitored time of arrival.
    Type: Grant
    Filed: May 17, 2012
    Date of Patent: October 20, 2015
    Assignee: BAR ILAN UNIVERSITY
    Inventors: Avinoam Zadok, Yair Antman, Luc Thevenaz
  • Patent number: 9130994
    Abstract: Techniques for avoiding dynamic domain name system (DNS) collisions are disclosed. In one particular exemplary embodiment, the techniques may be realized as a method for avoiding dynamic domain name system (DNS) collisions comprising: storing a first location associated with a first client device, a second location associated with a second client device, and a third location associated with a network, receiving, from the first client device, a first notification indicating an Internet Protocol (IP) address via the network, receiving, from the second client device, a second notification indicating the IP address via the network, determining a most likely owner of the network between the first client device and the second client device based on the first location, the second location, and the third location, and applying a content filtering policy associated with the first client device when the first client device is determined to be the most likely owner.
    Type: Grant
    Filed: March 9, 2011
    Date of Patent: September 8, 2015
    Assignee: Symantec Corporation
    Inventor: Keith Newstadt
  • Patent number: 9118412
    Abstract: A system for performing in-band reflection analysis in a passive optical network. The system comprises an optical line terminal (OLT) that includes a transceiver for transmitting continuous downstream data modulated on a first wavelength and receiving upstream burst data modulated on a second wavelength, the OLT further includes a receiver for receiving signals reflected from the PON that are modulated on the first wavelength, wherein the continuous downstream data comprises user data and a test data pattern; and a reflection analysis unit for cross-correlating between a time-shifted version of the transmitted test data pattern and the reflected signals, wherein the test data pattern is time-shifted relatively for an optical location to be tested.
    Type: Grant
    Filed: September 27, 2011
    Date of Patent: August 25, 2015
    Assignee: Broadcom Corporation
    Inventors: Amiad Dvir, Assaf Naor
  • Publication number: 20150131988
    Abstract: The length of the optical fiber section under tension expands by a certain amount that is proportional to the level of tension applied to it. Monitoring the variations in the phase of the arriving signal allows to discover a fiber that is subject to a certain level of mechanical tension. With the method and apparatus according to the present invention it is possible to protect optical communication channels against failures in an optical transmission fiber that are caused by any kind of mechanical disturbances.
    Type: Application
    Filed: November 14, 2013
    Publication date: May 14, 2015
    Applicant: ADVA Optical Networking SE
    Inventors: Mohammad Alfiad, Mark Filer, Ted Rabenko, Sorin Tibuleac
  • Patent number: 9031403
    Abstract: A method includes sweeping an optical frequency of an optical signal by an optical transmitter controlling an electric-field information signal corresponding to a transmitted signal, providing different polarization states for individual frequencies of the optical signal by the optical transmitter controlling a mixture of a first electric-field information signal corresponding to a first transmitted signal and a second electric-field information signal corresponding to a second transmitted signal, obtaining, for individual frequencies of the optical signal, polarization dependent characteristics corresponding to different frequencies, when the optical transmitter sweeps the frequency of the optical signal, by an optical receiver calculating a polarization-dependent characteristic of an optical transmission line between the optical transmitter and the optical receiver, based on items of received-electric-field information corresponding to the different polarization states, and obtaining statistical information
    Type: Grant
    Filed: June 12, 2013
    Date of Patent: May 12, 2015
    Assignee: Fujitsu Limited
    Inventors: Hisao Nakashima, Takeshi Hoshida
  • Patent number: 9025952
    Abstract: An exemplary method is provided for determining a maximum transmission distance for an optical link that has heterogeneous types of optical fiber segments. The method includes retrieving from a database a maximum transmission reach value for each type of optical fiber present in the optical link. A length of each type of the optical fiber to reach a distance is computed, where, for each type of the optical fiber present in the optical link, segments are summed from a starting point to the distance to determine the length of each type of the optical fiber along the optical link. The length for each type of the optical fiber in the optical link is normalized by multiplying the length of each type of the optical fiber by a weight chosen as a function of the maximum transmission reach value for each type of said optical fiber.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: May 5, 2015
    Assignee: Alcatel Lucent
    Inventors: Annalisa Morea, Florence Leplingard, Jean-Christophe Antona
  • Patent number: 9002201
    Abstract: For testing an optical network, a transmission module transmits a first optical power level on a first optical port of an optical assembly. The optical assembly includes the first optical port, one or more of an optical cable and an optical waveguide, and a second optical port. The optical assembly is installed in an assembled computer in a state suitable for an end user. A measurement module measures a second optical power level on the second optical port, and a determination module determines a quality level by determining if the second optical power level is below a quality threshold value. The transmission module, the measurement module, and the determination module function within an assembled computer in a state suitable for an end user.
    Type: Grant
    Filed: January 3, 2013
    Date of Patent: April 7, 2015
    Assignee: International Business Machines Corporation
    Inventors: Alan F Benner, Richard B Finch, Jason Thomas Hirst, Peter Paul Lai, Gerald Glen Stanquist
  • Patent number: 9002198
    Abstract: An optical transmission system for optically transmitting information between apparatuses via an optical transmission path. The system includes: a sending unit that emits, to the optical transmission path, excitation light for detecting an inter-apparatus connection via the path; a responding unit that receives the excitation light from the path and emits detection light to the path using light energy of the excitation light; a response receiving unit that receives the detection light from the path and outputs a detection light current; a detecting unit that detects presence/absence of the inter-apparatus connection based on the detection light current; a light signal transmitting unit that emits, to the path, a light signal for optically transmitting the information based on the detection result by the detecting unit; and a light signal receiving unit that receives the light signal from the path.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: April 7, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Tsuyoshi Ikushima, Osamu Shibata, Yoshiyuki Saito
  • Publication number: 20150086194
    Abstract: A method for testing the operation of an optical fiber cable in a communication network using an optical loss test set (OLTS) instrument includes receiving a range of identifiers of fibers to be tested. Identifiers of a first fiber set to be tested are displayed. The first fiber set comprises one or more fibers. The first fiber pair is included in the range. The first fiber pair is a next fiber pair to be tested. A determination is made whether the first fiber set is connected to the OLTS instrument. In response to determining that the first fiber set is connected to the OLTS instrument, a test of the first fiber set operation is performed using the OLTS instrument. Identifiers of a second fiber set are displayed. The second fiber set is included in the range and constitutes a next fiber set to be tested.
    Type: Application
    Filed: September 20, 2013
    Publication date: March 26, 2015
    Applicant: FLUKE CORPORATION
    Inventor: Harlan Kassler
  • Publication number: 20150086195
    Abstract: A method is provided for detecting movement indicative of intrusion events on optical drop fibers of a network where the individual drop fiber can be identified to locate the event. The method uses a monitor system at the network end and multiplexing the monitor signal along the individual fibers to the respective terminals. At each of the terminals, the monitor signal is returned unchanged or in modified form along the same or different fibers to the network end. At the network end the received monitor signals is analyzed for changes in said monitor signals indicative of movement. Which one or more of the drop fibers has triggered the alarm is determined by modifying the monitor signal in wavelength or polarization, or by applying a modulation at the source and/or at multiplexing and/or at returning so that the monitor signal of one drop fiber has a difference from the monitor signal of another drop fiber.
    Type: Application
    Filed: August 12, 2014
    Publication date: March 26, 2015
    Inventors: Cary R. Murphy, Mark K. Bridges, David E. Vokey, Daniel Goertzen
  • Publication number: 20150086193
    Abstract: An optical transmitter configured to mitigate the adverse effects of fiber nonlinearity by altering the transmitted constellation symbols based on specific nonlinear characteristics of a fiber-optic link over which the optical transmitter is configured to transmit and on an a priori estimate of the nonlinear component of the optical-signal distortion in that fiber-optic link. In an example embodiment, each constellation symbol is altered by a respective perturbation amount determined using (i) a calculated or measured nonlinear transfer function corresponding to the fiber-optic link and (ii) a set of neighboring constellation symbols that are expected to contribute to the nonlinear distortion of the optical signal carrying the present constellation symbol due to the fiber nonlinearity. In various embodiments, different appropriate perturbation amounts can be selected to approximately pre-compensate nonlinear distortions caused by various nonlinear optical effects, such as four-wave mixing, etc.
    Type: Application
    Filed: September 20, 2013
    Publication date: March 26, 2015
    Applicant: ALCATEL-LUCENT USA INC.
    Inventors: Xiang Liu, Peter J. Winzer, Chandrasekhar Sethumadhavan
  • Patent number: 8971701
    Abstract: A universal optical receiver may include an optical channel monitor configured to acquire spectral data for an optical signal on at least one selected optical channel, a tunable local oscillator configured to be tuned to a center frequency of the optical signal on the at least one selected optical channel, a storage device configured to store data associated with the optical signal responsive to acquisition of the spectral data and tuning of the tunable local oscillator, and processing circuitry configured to execute an algorithm that employs a plurality of binary distinctions based on physical characteristics of the optical signal and employs at least one calculation of figure of merit associated with a series of parameter values of the optical signal to identify a format of the optical signal.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: March 3, 2015
    Assignee: The Johns Hopkins University
    Inventors: Eric J. Adles, Michael L. Dennis, Raymond M. Sova, Joseph E. Sluz, Michael G. Taylor, Curtis R. Menyuk, John W. Zweck
  • Publication number: 20150055947
    Abstract: A remote node, e.g., a client-side node or a service-side node, writes wavelength information into an overhead message of a packet carried by an optical signal when an optical port associated with the remote node is deployed. The overhead message explicitly identifies the wavelength channel associated with the newly deployed optical port to a hub node in a WDM optical network. The hub node identifies the new wavelength channel associated with the newly deployed optical port based on the overhead message to enable the hub node to associate the new wavelength channel with the newly deployed optical port.
    Type: Application
    Filed: August 23, 2013
    Publication date: February 26, 2015
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Ming Xia, Stefan Dahlfort, David Hood
  • Publication number: 20150055948
    Abstract: Systems and methods of aligning an optical interface assembly with an integrated circuit (IC) are disclosed. The method includes emitting light from an optical transmitter, passing the emitted light through the optical interface assembly in a first direction, and reflecting the emitted light from a reflective surface disposed immediately adjacent a front end of the optical interface assembly to define reflected light that travels back through the optical interface assembly in a second direction that is substantially opposite the first direction. The reflected light is received by an optical receiver that generates in response a receiver signal. The relative position of the optical interface assembly and the IC is adjusted to achieve an aligned position based on the receiver signal. The disclosure is also directed to a test plug for aligning an optical interface assembly to the IC.
    Type: Application
    Filed: November 26, 2013
    Publication date: February 26, 2015
    Applicant: Corning Cable Systems LLC
    Inventors: Douglas Llewellyn Butler, Ying Geng, Micah Colen Isenhour, Christopher Paul Lewallen, James Phillip Luther, Andrea Matiss
  • Publication number: 20150003826
    Abstract: According to one embodiment of a system for measuring differential mode delay couples with a pulse generator to generate an input electrical pulse, a photo detector to receive optical pulse from an optical fiber, and a digital oscilloscope to receive an output electrical pulse transmitted from the photo detector, the system includes: a laser diode, a first lens and a second lens, a pigtail, and a spliced optical connector, wherein the laser diode receives the input electrical pulse to produce a laser beam, the first lens and the second lens focus the laser beam into the pigtail, the spliced optical connector connects the pigtail and the input end face of the optical fiber such that the optical pulse from the output end face of the optical fiber is received by the photo detector.
    Type: Application
    Filed: June 27, 2013
    Publication date: January 1, 2015
    Inventors: Nien-Tsu Chiang, Kuei-Huang Chou
  • Publication number: 20140376910
    Abstract: The present invention relates to an apparatus and a method for fiber optic perturbation sensing, in which it is possible to easily confirm whether an intrusion is occurred, an intrusion position, and an intrusion object by dividing an optical signal output from the optical signal generation unit, progressing the divided optical signals to optical paths having different lengths, coupling the divided optical signals to generate an sensing optical signal, outputting the generated sensing optical signal to the sensing optical fiber, dividing the sensing optical signal returning from the sensing optical fiber, progressing the divided sensing optical signals to the optical paths having different lengths, and coupling the divided sensing optical signals to generate an interference sensing optical signal.
    Type: Application
    Filed: December 14, 2012
    Publication date: December 25, 2014
    Inventors: Hyo Sang Kim, Ho Jin Jeong, Jae Chul Yong
  • Patent number: 8909041
    Abstract: A method for determining an optical signal-to-noise ratio penalty as a measure for a quality of an optical signal transmitted via an optical link between a source optical node and a destination optical node in an optical network, the method includes collecting information of the optical link; determining a configuration parameter Pconf of the optical link based on the information of the optical link; adjusting the configuration parameter Pconf to an adjusted configuration parameter P?conf according to linear impairments in the optical link; and determining the optical signal-to-noise ratio penalty based on a non-linear function of the adjusted configuration parameter P?conf, the non-linear function accounting for non-linear impairments in the optical link.
    Type: Grant
    Filed: June 1, 2012
    Date of Patent: December 9, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Yabin Ye, Tong Wu, Sen Zhang
  • Patent number: 8891958
    Abstract: There is provided a method of determining transmission quality of a path in an optical communication network system obtained by connecting a plurality of networks, the method including: acquiring a value representing transmission performance corresponding to a network condition of each of spans in the path in the optical communication network system; and determining the transmission quality of the path on the basis of the acquired value representing transmission performance corresponding to the network condition of each of spans.
    Type: Grant
    Filed: February 15, 2012
    Date of Patent: November 18, 2014
    Assignee: Fujitsu Limited
    Inventors: Takehiro Fujita, Shigeru Ishii, Takuya Miyashita
  • Patent number: 8886037
    Abstract: Provided is a waveform reconstruction device capable of easily reconstructing an accurate time waveform of an optical signal without using an ultrafast time gate or a reference light source.
    Type: Grant
    Filed: March 2, 2010
    Date of Patent: November 11, 2014
    Assignee: Osaka University
    Inventors: Tsuyoshi Konishi, Takuya Kato, Hiroomi Goto
  • Patent number: 8873946
    Abstract: A system and method is disclosed that allows for the monitoring, analyzing and reporting on performance, availability and quality of optical network paths. The correlation of PM parameter metrics to client connections, coupled with threshold-based alarm generation provides a proactive and predictive management, reporting and analyzing of the health and effectiveness of individual path connections to alert Operational Support (OS) staff and/or customers to signal degradation and impending Network Element (NE) failures. The system and method performs in real-time processing intervals required for alarm surveillance in a telecommunications network.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: October 28, 2014
    Assignee: AT&T Intellectual Property II, L.P
    Inventors: David Mayo, Meei-Ling Chen
  • Patent number: 8873948
    Abstract: A border node of an optical network receives optical channel traffic parameter(s) associated with an optical channel from an optical channel originator external to the optical network. The received parameters are used to determine the suitability of at least one optical path within the optical network for an externally originating optical channel. If a suitable optical path is determined, an optical channel availability message indicating the availability at the border node of an optical path within the optical network for the optical channel is sent to the optical channel originator. The optical channel originator determines an available optical channel status of the optical channel from the received optical channel availability message for the optical channel.
    Type: Grant
    Filed: April 27, 2011
    Date of Patent: October 28, 2014
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventors: Diego Caviglia, Giulio Bottari, Daniele Ceccarelli
  • Patent number: 8855486
    Abstract: A remotely controlled fiber testing method has the steps of: building a fiber network system including a local fiber station and a remote fiber station; sending a modulated signal to the remote fiber station by the local fiber station; demodulating the modulated signal to obtain a control command by the remote fiber station; executing the control command to obtain a testing result by the remote fiber station; modulating the testing result and sending the testing result back to the local fiber station; and demodulating the testing result by the local fiber station. Only one technician appointed to the local fiber station is sufficient to do the testing action. Therefore, the personnel cost is effectively reduced.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: October 7, 2014
    Assignee: Polarlink Technologies, Ltd.
    Inventors: Shih-Tien Lin, Fu-Chun Hung, Yu-Shu Chen, Ching-Wen Hsiao, Chun-Hung Su
  • Publication number: 20140294380
    Abstract: An optical device includes an optical waveguide that includes an incident waveguide, parallel waveguides along an electrode, and emission waveguides, formed on a substrate having an electro-optical effect, a first emission waveguide among the emission waveguides is set as an output waveguide of signal light, for output to an external destination and a second emission waveguide among the emission waveguides is set as a monitoring optical waveguide for the signal light; a photodetector that is disposed over the monitoring optical waveguide; and a groove formed on a portion of the substrate, where the photodetector of the monitoring optical waveguide is disposed. The monitoring optical waveguide has a width that, as compared with the width at a starting point side, is formed to increase as the monitoring optical waveguide approaches the groove.
    Type: Application
    Filed: February 28, 2014
    Publication date: October 2, 2014
    Applicant: Fujitsu Optical Components Limited
    Inventors: Masaki Sugiyama, Shinji Maruyama
  • Publication number: 20140294379
    Abstract: Various systems and methods for using credits to determine cable length are described herein. A number of available credits is determined at a transmitter, the credits being received at the transmitter from a receiver, and each of the credits being used for the transmitter to transmit a packet to the receiver. An average number of credits for a period is determined. The cable length between the transmitter and the receiver is determined based on the average number of credits for the period.
    Type: Application
    Filed: March 28, 2013
    Publication date: October 2, 2014
    Applicant: Cisco Technology, Inc.
    Inventors: Rajesh L G, Deepak Srinivas Mayya, Lalit Kumar
  • Patent number: 8837937
    Abstract: A detecting device that detects insertion loss of fiber route and return loss of individual events in an optical fiber network based on signals from dual paths to obtain various kinds of reference information of the optical fiber network. When the first path is selected, a detection signal produced using frequency modulated continuous wave (FMCW) technique is output to the optical fiber network. A return signal of the detection signal is used to analyze the position and return loss of various events in the optical fiber network. When the second path is selected, a common detection light is output to the optical fiber network. Based on the return signal of the common detection light, the insertion loss and total return loss of the entire network are obtained.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: September 16, 2014
    Assignee: Polarlink Technologies, Ltd.
    Inventors: Ching-Wen Hsiao, Hsuan-Hung Wu, Shih-Tien Lin, Fu-Chun Hung, Yu-Shu Chen, Ching-Lin Wu, Chun-Hung Su
  • Patent number: 8831422
    Abstract: The present invention relates to the field of communication transmission, and in particular, to a method for generating a probe pulse and a coherent optical time domain reflectometer. The coherent optical time domain reflectometer includes: a control unit, configured to generate a first pulse signal and a second pulse signal which have a same period T, where the second pulse signal lags behind the first pulse signal, and T satisfies T?t+2L/C; a driving unit, configured to generate a frequency change driving signal according to the first pulse signal; a continuous light laser device, configured to generate, as driven by the frequency change driving signal, continuous light having a changing frequency and an unchanging frequency spectrum width; and a probe pulse generating unit, configured to modulate the continuous light according to the second pulse signal to generate a probe pulse.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: September 9, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Zhiyong Feng, Shaofeng Qiu, Yijia Wei
  • Patent number: 8818189
    Abstract: A transmission-path-type specifying apparatus includes an optical filter that extracts a plurality of different wavelength components from light including wavelength components occurring at the time of communication; an optical switch that simultaneously transmits same pulse signals superposed on light of the extracted wavelength components. The apparatus also includes an ASE modulation controlling unit that obtains a delay-time difference among the transmitted pulse signals when arriving at a destination via a transmission path; a characteristic-value calculating unit that calculates a characteristic value of the transmission path corresponding to a reference time varied depending on the obtained delay-time difference and a type of the transmission path; and a fiber-type determining unit that specifies the type of the transmission path based on the calculated characteristic value.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: August 26, 2014
    Assignee: Fujitsu Limited
    Inventor: Futoshi Izumi
  • Patent number: 8811816
    Abstract: The disclosure claims a method and system for detecting optical fiber connection.
    Type: Grant
    Filed: March 17, 2011
    Date of Patent: August 19, 2014
    Assignee: ZTE Corporation
    Inventor: Long Li
  • Patent number: 8811815
    Abstract: A method includes generating a test signal and modulating the test signal. The method may also include transmitting the test signal on an optical path, where the optical path may include a number of add-drop multiplexer devices and amplifiers. The method may also include receiving the test signal at a destination device and converting the received test signal into an electrical signal. The method may further include identifying a portion of the electrical signal that is associated with the modulated test signal.
    Type: Grant
    Filed: April 20, 2009
    Date of Patent: August 19, 2014
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Tiejun J. Xia, Glenn A. Wellbrock
  • Patent number: 8805199
    Abstract: A dispersion compensation design system includes a changing unit setting a changed value for the amount of dispersion compensation for a span connecting nodes constituting an optical network; a path classification unit determining whether respective paths in the optical network are capable of transmission with the changed value and classifying one or more of the paths as second category paths based on the determination results; an updating unit updating the amount of dispersion compensation with the changed value if the number of the second category paths in the latest classification result is less than the number of the second category paths in the retained previous classification result; and a repeating unit that, if not all of the paths in the optical network are capable of transmission, prevents use of combinations of amounts of dispersion compensation applied to the spans in the second category paths in the latest classification result.
    Type: Grant
    Filed: November 21, 2011
    Date of Patent: August 12, 2014
    Assignee: Fujitsu Limited
    Inventors: Kazuyuki Tajima, Tomohiro Hashiguchi, Yutaka Takita
  • Publication number: 20140186030
    Abstract: Various embodiments provide for detection of tapping of an optical signal. In one embodiment an optical fiber includes a cladding region and first and second core regions. The first core region has a first core medium having a first mode-dependent loss (MDL) figure of merit. The second core region has a second core medium having a second different MDL figure of merit. Tapping of the optical signal may be determined to occur when the MDL of the first and second optical signals differs by a predetermined threshold value.
    Type: Application
    Filed: December 28, 2012
    Publication date: July 3, 2014
    Inventors: Peter J. Winzer, Kyle C. Guan, Emina Soljanin
  • Publication number: 20140161444
    Abstract: A remotely controlled fiber testing method has the steps of: building a fiber network system including a local fiber station and a remote fiber station; sending a modulated signal to the remote fiber station by the local fiber station; demodulating the modulated signal to obtain a control command by the remote fiber station; executing the control command to obtain a testing result by the remote fiber station; modulating the testing result and sending the testing result back to the local fiber station; and demodulating the testing result by the local fiber station. Only one technician appointed to the local fiber station is sufficient to do the testing action. Therefore, the personnel cost is effectively reduced.
    Type: Application
    Filed: December 12, 2012
    Publication date: June 12, 2014
    Applicant: POLARLINK TECHNOLOGIES, LTD.
    Inventors: Shih-Tien LIN, Fu-Chun HUNG, Yu-Shu CHEN, Ching-Wen HSIAO, Chung-Hung SU
  • Patent number: 8750704
    Abstract: A method and circuit are provided for implementing reduced signal degradation for fiber optic modules, and a design structure on which the subject circuit resides. Responsive to a detected signal input, an optical misalignment calculation is performed. A voltage potential for a lens shape control is selected responsive to the optical misalignment calculation. An optical signal loss calculation and threshold compare are performed. Responsive to the optical signal loss calculation less than the threshold, the lens shape and voltage potential are fixed. A fluidic lens provides variable lens shape responsive to the selected voltage potential being applied to the fluidic lens.
    Type: Grant
    Filed: January 22, 2010
    Date of Patent: June 10, 2014
    Assignee: International Business Machines Corporation
    Inventors: Joseph Kuczynski, Arvind Kumar Sinha
  • Publication number: 20140112658
    Abstract: A method of automated testing and evaluation of a node of a communications network, the method comprising: a management computer interacting with the node to discover fibre trails within the node that can be safely tested; and the management computer interacting with the node to test at least continuity of each identified fibre trail that can be safely tested
    Type: Application
    Filed: October 18, 2012
    Publication date: April 24, 2014
    Inventors: DANE HURLEY, SCOTT KOHLERT
  • Publication number: 20140105595
    Abstract: Optical amplification stage (1) for OTDR monitoring, comprising a first (2a) and a second optical signal path (2b), a first (3a) and a second optical amplifier (3b), a first optical coupler (4a) placed along the first optical signal path downstream the first optical amplifier, a second optical coupler (4b) placed along the second optical signal path downstream the second optical amplifier, an optical by-pass path (5) optically connecting the first and the second optical coupler, a first (11a) and a second optical reflector (11b) optically connected to respectively the first and second optical coupler, and an optical filter (10) placed along the optical by-pass path which has attenuation high on the whole WDM band and low at the OTDR wavelength(s).
    Type: Application
    Filed: October 9, 2013
    Publication date: April 17, 2014
    Applicant: PADTEC S.A.
    Inventors: GIORGIO GRASSO, ANDREA MELLONI, ALDO RIGHETTI, FAUSTO MELI
  • Patent number: 8699875
    Abstract: The invention relates to a system and method of dispersion measurement in an optical fiber network. The invention provides means for transmitting from a transmitting node, using a single tunable laser transmitter, two consecutive bursts of data at different wavelengths ?1 and ?2 to a receiver node, wherein each burst of data comprises a unique sequence of amplitude modulated data, and wherein the two sequences are injected with a fixed known delay. The delay between the two consecutive bursts of data is maintained by selective switching of the tunable laser, such that clock recovery circuitry at the receiver node remains locked during the delay between the two bursts. The dispersion measurements method of the present invention is based on walk off and bit position detection between two wavelengths suitable for fast optical burst switching network is described. This method does not require an operator, extra equipment, or traffic interruption on the network.
    Type: Grant
    Filed: July 19, 2011
    Date of Patent: April 15, 2014
    Assignee: Intune Networks Limited
    Inventors: Emilio Bravi, Giuseppe Tali, David McDonald, Michael Todd, David Bernard
  • Patent number: 8693865
    Abstract: A data processing device is connectable to a communication network and operable to receive data associated with an attenuation characteristic of a transmission line of a cable in a cable communication subsystem, the subsystem comprising a transmitter and/or receiver coupled to the cable. The data processing device is responsive to the received data to initiate a security procedure.
    Type: Grant
    Filed: January 11, 2010
    Date of Patent: April 8, 2014
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Jerry Aguren
  • Publication number: 20140086576
    Abstract: A computer device may include logic configured to receive a selection of a start node and an end node in an optical network and obtain network topology information relating to the optical network. The logic may be further configured to determine link latencies for particular links in the optical network; determine a least latency path between the start node and the end node based on the obtained network topology information and the determined link latencies, and wherein the least latency path includes one or more of the particular links; determine one or more alternate paths to the determined least latency path; determine channel availability for the least latency path and the one or more alternate paths; and generate a user interface that relates the least latency path and the one or more alternate paths to the determined channel availability.
    Type: Application
    Filed: September 21, 2012
    Publication date: March 27, 2014
    Applicant: VERIZON PATENT AND LICENSING, INC
    Inventors: Gary L. Campbell, Oommen Mathews
  • Patent number: 8682163
    Abstract: A detecting method, an apparatus, and a system in an Optical Distribution Network (ODN) are provided. The method includes: an Optical Line Termination (OLT) reserves a test window, and an Optical Network Unit (ONU) stops sending an uplink signal in the test window, the OLT emits a downlink test signal having a wavelength the same as that of the uplink signal in the test window, the OLT receives backward signals of the downlink test signal, in which the backward signals include a backward scattered signal and a backward reflected signal, processes the backward signals, and obtains state information of the ODN according to the backward signals. The method does not need to add other hardware, and the downlink signal is sent normally in the downlink. The implementation is low in the cost and easy in the technology.
    Type: Grant
    Filed: July 22, 2011
    Date of Patent: March 25, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Sulin Yang
  • Patent number: 8682172
    Abstract: In one example embodiment, an optoelectronic communications assembly having an optical receiver or an optical transmitter includes an optical interface disposed at an end thereof and through which optical signals are communicated by the optical receiver or optical transmitter. The optoelectronic communications assembly also includes an electronic component and a first electrical interface disposed at the optical interface end of the optical communications assembly and communicatively coupled to the electronic component.
    Type: Grant
    Filed: August 9, 2010
    Date of Patent: March 25, 2014
    Assignee: Finisar Corporation
    Inventor: Sunil Priyadarshi
  • Publication number: 20140056582
    Abstract: In general, techniques are described to detect potential issues with optical fibers. The techniques may be implemented using various optical network hardware. An example optical network unit (ONU) includes a network interface coupled to an optical fiber through which the ONU communicates with an optical line terminal (OLT). The ONU further includes a control unit that determines at least a first signal strength and a second signal strength of a signal received via the optical fiber, determines a rate of signal strength degradation based on the first signal strength and the second signal strength, compares the rate of signal strength degradation to a rate threshold so as to determine a potential issue with the optical fiber, and based on the comparison, causes the network interface to send a message to the OLT indicating a potential issue with the optical fiber to which the ONU connects to communicate with the OLT.
    Type: Application
    Filed: August 27, 2012
    Publication date: February 27, 2014
    Applicant: CALIX, INC.
    Inventor: Harold A. Roberts
  • Patent number: 8655171
    Abstract: A method and a device for an optical power budget in a passive optical network are disclosed in the present invention, wherein said method includes: acquiring a corresponding minimum optical link loss according to a transmission requirement of a passive optical network with a large splitting ratio or long distance (710); selecting an optical transmitter with large power and an optical receiver with high sensitivity as a combination of an optical transmitter of an Optical Line Terminal (OLT) and an optical receiver of an Optical Network Unit (ONU) in an optical link, as well as a combination of an optical receiver of the OLT and an optical transmitter of the ONU in the optical link according to the minimum optical link loss to compose a passive optical network system comprising the OLT, an Optical Distribution Network (ODN), and ONUs connected in sequence (720).
    Type: Grant
    Filed: June 11, 2010
    Date of Patent: February 18, 2014
    Assignee: ZTE Corporation
    Inventors: Jidong Xu, Boshan Zhang
  • Publication number: 20140029938
    Abstract: A method includes sweeping an optical frequency of an optical signal by an optical transmitter controlling an electric-field information signal corresponding to a transmitted signal, providing different polarization states for individual frequencies of the optical signal by the optical transmitter controlling a mixture of a first electric-field information signal corresponding to a first transmitted signal and a second electric-field information signal corresponding to a second transmitted signal, obtaining, for individual frequencies of the optical signal, polarization dependent characteristics corresponding to different frequencies, when the optical transmitter sweeps the frequency of the optical signal, by an optical receiver calculating a polarization-dependent characteristic of an optical transmission line between the optical transmitter and the optical receiver, based on items of received-electric-field information corresponding to the different polarization states, and obtaining statistical information
    Type: Application
    Filed: June 12, 2013
    Publication date: January 30, 2014
    Inventors: Hisao Nakashima, Takeshi Hoshida
  • Patent number: 8625986
    Abstract: A method and system to economically monitor an optical OOK signal that can detect perceptible changes in signal quality and identify the type of optical impairment causing the change. The invention requires a new and novel combination of known techniques to create an eye diagram of the transmitted pulse in a wavelength division multiplexing systems and then removing the noise from the eye diagram. Economy of operation is achieve by using asynchronous sampling techniques for generating the eye diagram. The resulting “cleaner” eye diagram is then analyzed to identify any changes in performance. In the preferred embodiment, the analysis is conducted on histograms generated from eye diagram, the histograms are computed at a number of points across the optical signal pulse period.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: January 7, 2014
    Assignee: TTI Inventions A LLC
    Inventors: Ronald A. Skoog, Thomas Clyde Banwell, Haim Kobrinski, Sarry Habiby, Joel W. Gannett, Russell Fischer
  • Publication number: 20130322874
    Abstract: A detecting device that detects insertion loss of fiber route and return loss of individual events in an optical fiber network based on signals from dual paths to obtain various kinds of reference information of the optical fiber network. When the first path is selected, a detection signal produced using frequency modulated continuous wave (FMCW) technique is output to the optical fiber network. A return signal of the detection signal is used to analyze the position and return loss of various events in the optical fiber network. When the second path is selected, a common detection light is output to the optical fiber network. Based on the return signal of the common detection light, the insertion loss and total return loss of the entire network are obtained.
    Type: Application
    Filed: January 8, 2013
    Publication date: December 5, 2013
    Applicant: Polarlink Technologies, Ltd.
    Inventors: Ching-Wen Hsiao, Hsuan-Hung Wu, Shih-Tien Lin, Fu-Chun Hung, Yu-Shu Chen, Ching-Lin Wu, Chun-Hung Su
  • Patent number: 8594500
    Abstract: A method includes outputting an optical signal from an optical transmitter; causing the optical signal to propagate through equipment of an optical communication site and to loop back to an optical receiver; measuring optical powers, respectively, based on taps proximate to the optical transmitter and the optical receiver; calculating an optical power loss based on the optical powers measured; determining whether the optical power loss is an acceptable value; and indicating when the optical power loss is not the acceptable value.
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: November 26, 2013
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Tiejun J. Xia, Glenn A. Wellbrock, Danny Peterson