Tdm System Patents (Class 398/35)
  • Patent number: 11843857
    Abstract: An accessory capable of promptly notifying an electronic apparatus of its state change. The accessory is detachably connected to an electronic apparatus. A first transmission unit transmits first information among information stored in the accessory to the electronic apparatus in response to periodic first communication from a first communication unit of the electronic apparatus. A second transmission unit responds to inquiry by second communication from a second communication unit of the electronic apparatus. A notification unit notifies the electronic apparatus of state change of the accessory when the electronic apparatus is in a first state or a second state and the state of the accessory is changed. In the first state, the first communication is stopped and the second communication unit is in a standby mode. In the second state, power supply to the first communication unit is stopped and the second communication unit is in the standby mode.
    Type: Grant
    Filed: April 25, 2022
    Date of Patent: December 12, 2023
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kazunori Gouji
  • Patent number: 11632182
    Abstract: In the method, a first device receives a mixed signal including a target signal from a target device among a plurality of second devices and an interfering signal from the plurality of second devices. The first device determines a distribution characteristic of an amplitude of the mixed signal within an amplitude variation range, the distribution characteristic being associated with the target device and an interfering device generating the interfering signal. The first device determines the interfering device from the plurality of second devices based on the distribution characteristic. An interfering device in a communication system may be detected in real-time and accurately.
    Type: Grant
    Filed: January 19, 2021
    Date of Patent: April 18, 2023
    Assignee: Nokia Solutions and Networks Oy
    Inventors: Chenhui Ye, Xiaofeng Hu, Kaibin Zhang
  • Patent number: 11424829
    Abstract: Circuitry of an optical line terminal (OLT) can be controlled to be compatible with optical modules of different optical protocols having different electrical connectivity requirements. In some embodiments, the OLT has a controller that is configured to communicate with an optical module plugged or otherwise mated with a socket of the OLT in order to discover a module type of the optical module. Based on the detected module type, the controller is configured to control the electrical characteristics of the OLT circuitry so that it is compatible with the electrical and operational requirements of the optical module. Thus, the OLT is compatible for use with any of a plurality of optical module types.
    Type: Grant
    Filed: June 21, 2021
    Date of Patent: August 23, 2022
    Assignee: ADTRAN, Inc.
    Inventors: Jerry Greer, Jared Lee Oldacre, Vern Brethour
  • Patent number: 10277314
    Abstract: The received signal strength of individual optical data bursts may be estimated based on the detection of bit patterns within each data burst associated with an amplifier recovery time period. The burst-by-burst estimates can be made faster than existing techniques.
    Type: Grant
    Filed: September 10, 2017
    Date of Patent: April 30, 2019
    Assignee: Nokia Solutions and Networks OY
    Inventors: Roy B Tebbe, Kaleb Q Droskiewicz, Bradley L Mendenhall
  • Patent number: 9397778
    Abstract: A tunable optical network unit (ONU) for a multi-wavelength passive optical network (MW PON) system and an operation method thereof are provided. The tunable ONU includes a cyclic tunable filter configured to have cyclic wavelength transmission properties that allow all wavelength channels of both a downstream signal and an upstream signal and to vary a wavelength to pass therethrough; a wavelength splitter configured to split an upstream signal wavelength band and a downstream signal wavelength band; a photodetector element configured to detect a downstream signal that is transmitted through the wavelength splitter, passing through the cyclic tunable filter which is aligned to a specific downstream signal wavelength channel; and a tunable transmitter configured to output to the wavelength transmitter an upstream signal of a wavelength channel that is determined based on an aligned downstream signal wavelength channel of the cyclic tunable filter.
    Type: Grant
    Filed: April 23, 2015
    Date of Patent: July 19, 2016
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Jie Hyun Lee, Heuk Park, Jyung Chan Lee, Sang Soo Lee
  • Patent number: 9020342
    Abstract: In a transmission control apparatus, connected communication devices are detected to find round trip time of transmission to each of the detected communication devices, and the order of each communication device is determined on the basis of the round trip time of transmission to that communication device depending upon the distance thereto. On the basis of the round trip times of transmission to, and the orders of, the communication devices, transmission wait times are determined for delaying transmission of control signals from the communication devices to notify the communication devices of the transmission wait times. When starting communication with the communication devices, timer start signals prompting the communication devices to start counting the transmission wait time are transmitted to the communication devices.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: April 28, 2015
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Masahiro Sarashina, Akihiro Takahashi
  • 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
  • Publication number: 20150030324
    Abstract: The optical transmitter includes a FP-LD, generating multiple-longitudinal mode light wave. The FP-LD is also driven by an electrical signal, modulates the electrical signal to the multiple-longitudinal mode light wave, and outputts the modulated multiple-longitudinal mode light wave. An optical coupler, coupled with the FP-LD, is used for feeding the modulated multiple-longitudinal mode light wave from the FP-LD to a fiber Bragg grating. The fiber Bragg grating is for filtering the received multiple-longitudinal mode light wave according to a parameter, and feeding back the optical signal generated after being filtered to the optical coupler. The optical coupler divides the optical signal, thus making the optical signal oscillate between the FP-LD and the fiber Bragg grating to form a oscillation cavity, and outputs a single mode optical wave with constant wavelength and power.
    Type: Application
    Filed: June 3, 2013
    Publication date: January 29, 2015
    Applicant: Alcatel Lucent
    Inventors: Qingjiang Chang, Zhensen Gao
  • Patent number: 8886035
    Abstract: Proposed is an efficient method of configuration of a transmitter and a receiver for realizing an optical transmission/reception module apparatus including at least one transmission wavelength and two or more reception wavelengths over a time division multiple access passive optical network or an optical network using multiple transmission/reception wavelengths. Further, proposed is a method of configuration of an apparatus which enables optical alignment and assembly in a single package by using a single lens and three different WDM optical filters for a reception module capable of receiving four wavelengths.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: November 11, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jong Deog Kim, Jong Jin Lee
  • 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: 8823539
    Abstract: A display method and apparatus provides an easy to interpret presentation of multiple channel data, in the form of columns where the height of the column represents the relative measurement. A threshold line provides an indication of whether the measurement is above or below the threshold. Greater detail and numeric measurement values can be displayed for individual channels while the multiple channel display is in view.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: September 2, 2014
    Assignee: Fluke Corporation
    Inventors: J. David Schell, Sena E. R. Janky
  • 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: 8744265
    Abstract: A passive optical network (PON) component comprising a processor coupled to a plurality of receivers, the processor configured to monitor a plurality of drifting laser wavelengths and cause the drifting laser wavelengths to be tuned to a plurality of pass-bands. Also disclosed is an optical network unit (ONU) comprising a receiver, a transmitter coupled to the receiver, and a partially-tunable laser coupled to the transmitter and having a drifting laser wavelength, wherein the drifting laser wavelength is periodically tuned to one of a plurality of pass-bands. Included is a method comprising monitoring a plurality of drifting laser wavelengths associated with a plurality of pass-bands, and reconfiguring a plurality of time division multiple access (TDMA) timeslots when one of the drifting laser wavelengths migrates from one pass-band to another pass-band.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: June 3, 2014
    Assignee: Futurewei Technologies, Inc.
    Inventor: Frank J. Effenberger
  • Patent number: 8712240
    Abstract: The embodiments of the present invention relate to communications technology, and disclose an optical power measurement method, an Optical Line Terminal (OLT), and an Optical Network Unit (ONU). The method includes: generating a Physical Layer Operation Administration Maintenance (PLOAM) message that includes an identifier of at least one ONU to be measured and information about a time bucket that is allocated to the ONU to be measured and is used for sending upstream optical signals; sending the PLOAM message to the multiple ONUs; receiving the upstream optical signals that are sent, in the allocated time bucket, by the ONU to be measured; and detecting the received upstream optical signals, and determining the optical power of the upstream optical signals. The present invention avoid waste of bandwidth caused in the prior art when the DBA is required to allocate bandwidth to the ONU to be measured for the purpose of detecting the optical power.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 29, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Ping Ding, Yinghua Dong, Xuanqin Liang, Guangdong Wu
  • Publication number: 20140105597
    Abstract: Techniques are disclosed that relate to synchronizing a clock on a network interface device with a clock on an optical line terminal (OLT). In one example, the technique to synchronizing the clocks may include monitoring one or more instances when the network interface device transmits information to the OLT and determining when a frame should be received by the network interface device based on the monitored one or more instances when the network interface device transmits information the OLT.
    Type: Application
    Filed: December 9, 2013
    Publication date: April 17, 2014
    Applicant: Calix, Inc.
    Inventors: Christopher T. Bernard, Dean M. Dunnigan
  • Patent number: 8538258
    Abstract: In a TDMA optical network, a clock data recovery module uses signal oversampling and preamble correlation together with enhanced performance modules to extract additional data from the upstream transmission signal. Information including duty cycle, ONT power estimation, signal noise and jitter can be extracted from the upstream signal using digital logic and used to tune network components and/or alleviate network conditions.
    Type: Grant
    Filed: May 8, 2008
    Date of Patent: September 17, 2013
    Assignee: Alcatel Lucent
    Inventor: Dusan Suvakovic
  • Publication number: 20130209096
    Abstract: Exemplary methods and apparatuses are provided for a method for correcting for a delay asymmetry of synchronization messages transmitted within a packet-switched network between a master clock and a slave clock, in which the delay asymmetry of the path connecting the master clock to the slave clock is determined and corrected locally within at least one link of said path. One or more signals are transmitted on one or more wavelengths over at least one optical fiber. The one or more signals are received and detected on the one or more wavelengths over the at least one optical fiber. The technique determines an arrival time difference between the received and detected one or more signals, and calculates a delay asymmetry of an adjacent link based on the time difference.
    Type: Application
    Filed: September 15, 2011
    Publication date: August 15, 2013
    Inventors: Michel Le Pallec, Dinh Thai Bui
  • Patent number: 8494362
    Abstract: A network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage for receiving a pluggable module wherein the pluggable module comprises Time Division Multiplexing (TDM) between an optical network interface and an electrical host interface.
    Type: Grant
    Filed: December 12, 2008
    Date of Patent: July 23, 2013
    Assignee: ADVA Optical Networking SE
    Inventor: Henning Hinderthuer
  • Publication number: 20130156423
    Abstract: There are disclosed systems and methods for detecting whether an Optical Network Unit (ONU) in a network may be causing a communications interference due to laser overlap. In one embodiment, an Optical Line Terminal (OLT) selects a pair of ONUs suspected of possibly causing laser overlap. The OLT then grants a first window to a first ONU for transmitting a first message, and grants to another ONU different from the pair of ONUs a second window for transmitting a second message. If the first message is not received by the OLT, then the OLT indicates that the first ONU may be causing laser overlap. In another embodiment, the OLT grants to an ONU a window for transmitting a message to the OLT. If the message is not received by the OLT when expected, then the OLT indicates that the ONU may be causing laser overlap. Other embodiments are disclosed.
    Type: Application
    Filed: December 15, 2011
    Publication date: June 20, 2013
    Applicant: CORTINA SYSTEMS, INC.
    Inventors: Dongsheng ZHANG, Eugene W. LEE, Wei YAO
  • Publication number: 20130089325
    Abstract: In a transmission control apparatus, connected communication devices are detected to find round trip time of transmission to each of the detected communication devices, and the order of each communication device is determined on the basis of the round trip time of transmission to that communication device depending upon the distance thereto. On the basis of the round trip times of transmission to, and the orders of, the communication devices, transmission wait times are determined for delaying transmission of control signals from the communication devices to notify the communication devices of the transmission wait times. When starting communication with the communication devices, timer start signals prompting the communication devices to start counting the transmission wait time are transmitted to the communication devices.
    Type: Application
    Filed: September 12, 2012
    Publication date: April 11, 2013
    Applicant: Oki Electric Industry Co., Ltd.
    Inventors: Masahiro SARASHINA, Akihiro Takahashi
  • Publication number: 20120315034
    Abstract: This invention provides a detecting device and a method for a passive optical network (PON), which includes: a laser device; a detector coupled to the laser device and generating an output signal at one of a first level when the laser device emits light and a second level when the laser device does not emit light; and a processor repeatedly detecting the output signal in a fixed period, and simultaneously counting a total number of changes that the output signal changes from the first level to the second level and the output signal changes from the second level to the first level so as to detect whether a light leakage occurs in the PON.
    Type: Application
    Filed: June 7, 2012
    Publication date: December 13, 2012
    Applicant: Delta Networks, Inc.
    Inventors: Chang-Hung Tien, San-Ching Kuo
  • Patent number: 8290362
    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: March 4, 2008
    Date of Patent: October 16, 2012
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: David Mayo, Meei-Ling Chen
  • Patent number: 8280249
    Abstract: The invention relates to a network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage for receiving a pluggable module which performs a traffic management of data transported via at least one optical fiber connected to said pluggable module.
    Type: Grant
    Filed: December 12, 2008
    Date of Patent: October 2, 2012
    Assignee: ADVA AG Optical Networking
    Inventors: Lars Friedrich, Henning Hinderthuer
  • Patent number: 8254779
    Abstract: Described herein are systems and methods for a field-configurable optical network terminal (ONT) device at a subscriber to provide one or more communication services to the subscriber. The field-configurable ONT device is of a modular design operable for the insertion of additional communication modules or removal of existing communication modules from the ONT device for scaling the device to increased or decreased communication capacity as desired.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: August 28, 2012
    Assignee: General Instrument Corporation
    Inventors: William A. Carleton, Jinwoo Lee, Charles F. Niesley, Frank J. Scullin, Kimberley A. Smedley
  • Publication number: 20120114331
    Abstract: The longest possible sleep time is selected while data missing is prevented in a PON system by referring to the link speeds and the queue buffer capacities of an OLT and ONUs. The OLT calculates a first sleep time candidate based on a first link speed at which the OLT communicates with an upper network and the capacity of an unused area of a first queue buffer where downstream data is held for each of the destination ONUs. Each of the ONUs calculates a second sleep time candidate based on a second link speed at which each of the ONUs communicates with a communication terminal and the capacity of an unused area of a second queue buffer where upstream data bound for the OLT is held. The smaller sleep time is determined and used to change one of the ONUs to a sleep mode.
    Type: Application
    Filed: October 17, 2011
    Publication date: May 10, 2012
    Applicant: HITACHI, LTD.
    Inventors: Makoto KAMIJO, Noboru OOSAWA, Satoshi KONNO
  • Publication number: 20110255866
    Abstract: A signal strength corresponding to an incoming optical burst from each of a plurality of optical nodes is measured. The measurements can be performed at system start-up, configuration/installation of the optical nodes and/or at certain intervals of operation of the optical nodes. Signal strength information for the optical nodes based on the measurements is stored in memory. When scheduling the optical nodes for transmission, a preferred transmission order is determined in response to the stored signal strength information. In an embodiment, the preferred order is determined to reduce differences in signal strength levels between consecutive optical bursts.
    Type: Application
    Filed: April 15, 2010
    Publication date: October 20, 2011
    Applicant: ALCATEL-LUCENT USA INC.
    Inventors: DOUTJE T. VAN VEEN, ADRIAAN J. DE LIND VAN WIJNGAARDEN, DUSAN SUVAKOVIC
  • Patent number: 7925158
    Abstract: A time division multiplexed measurement technique is used for spectral measurements in active wavelength division multiplexed loaded optical links, and offers instantaneous real-time correlation of performance and spectral parameters of the link, which is important for dynamic characterization of link performance during transient effects or polarization mode dispersion fluctuations.
    Type: Grant
    Filed: October 3, 2007
    Date of Patent: April 12, 2011
    Assignee: Acterna LLC
    Inventors: Alexey Turukhin, Enrico Gonzales
  • Patent number: 7920789
    Abstract: A system for communication of signals between remote devices and monitoring and control devices via fiber. The system in accordance with one aspect of the invention includes a plurality of remote interface units each coupled to a corresponding one of the remote devices, a base unit coupled to one or more monitoring devices and one or more control devices, and a central hub coupled between the base unit and the plurality of remote interface units. The central hub is coupled to the base unit by a first fiber optic link, and is coupled to the remote interface units by additional fiber optic links.
    Type: Grant
    Filed: January 5, 2009
    Date of Patent: April 5, 2011
    Assignee: Multidyne Electronics Inc.
    Inventors: Vincent Jachetta, Brian C. Moore, James G. Jachetta, Francis P. Jachetta
  • Patent number: 7865077
    Abstract: An optical communication system has two or more active interfaces, each controlling the transmission and reception of optical signals between a communication network and one or more subscriber terminals according to control information pertaining to the individual subscriber terminals. The control information used by all the active interfaces is stored in a memory. The optical communication system also has a standby interface that is functionally equivalent to the active interfaces, and an optical switching apparatus that switches data transmission paths among the network, the active and standby interfaces, and the subscriber terminals. If a fault is detected in an active interface, the standby interface extracts the control information of the faulty interface from the memory, and the optical switching apparatus switches the data transmission paths so that the standby interface replaces the faulty interface.
    Type: Grant
    Filed: April 10, 2007
    Date of Patent: January 4, 2011
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Toshiaki Mukojima
  • Patent number: 7826745
    Abstract: A method and apparatus for transmitting signals from a plurality of input channels over a TDM optical network, where each of the input channels contains an optical data signal and an electrical control signal containing control information relating to the optical data signal. In accordance with the invention, respective optical receivers convert the optical data signals to respective electrical data signals, which a TDM data multiplexer time-multiplexes to generate a multiplexed data signal. A TDM control signal multiplexer time-multiplexes the electrical control signals to generate a multiplexed control signal that is combined with said multiplexed data signal to generate a composite electrical signal. An optical transmitter generates a composite optical signal from the composite electrical signal that is transmitted over the network, optionally after WDM multiplexing it with other composite optical signals.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: November 2, 2010
    Assignee: International Business Machines Corporation
    Inventors: Casimer M. DeCusatis, Thomas A. Gregg
  • Patent number: 7822055
    Abstract: The Fibre Channel Credit Extender (FCCE) (600) is a network device that is disposed between and connected to an end node (210) and an optical repeater (220). The FCCE (600) contains as many buffer credits as necessary, to solve bandwidth problems in a network. In a situation where maximum bandwidth is required in both directions of a link, the FCCE (600) breaks a single logical link into three physically separated “linklets.” The short-distance linklets attain maximum bandwidth by use of the existing buffer credits of the end nodes. The long-distance linklet attains maximum bandwidth by use of very high receive buffer credits in the FCCEs (600). In this way, only those links that need maximum bandwidth over distances not covered by end-node credit counts need be attached to an FCCE (600). The FCCE (600) contains the optical repeater to gain distance on that link, and contains high credit count receive buffers to gain bandwidth on the link.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: October 26, 2010
    Assignee: QLogic Switch Products, Inc.
    Inventors: William R. George, Steven M. Betker
  • Patent number: 7822304
    Abstract: A laser beam multiplexer capable of easily multiplexing a plurality of laser beams is provided. A laser beam multiplexer includes a multiplexing element having a hollow portion with a sectional elliptical shape, in which the multiplexing element includes: a plurality of light-incident apertures guiding laser beams from outside toward one of two focal points of the hollow portion, a reflective layer arranged on a wall surface of the hollow portion, and multiplexing a plurality of incident laser beams while reflecting the plurality of laser beams, and a light-emitting aperture guiding laser beams multiplexed by the reflective layer toward outside.
    Type: Grant
    Filed: April 14, 2009
    Date of Patent: October 26, 2010
    Assignee: Sony Corporation
    Inventor: Shoji Hirata
  • Patent number: 7787765
    Abstract: A method and apparatus for initializing an end-to-end link in a fiber optic communications system in which a pair of nodes interconnect a pair of end devices. A first node, upon initializing a device link segment with an end device to which the node is coupled, sends a signal to the other node over a network link segment indicating that the sending node has initialized its device link segment. The first node completes initialization of the end-to-end link upon receiving a signal from the other node over the network link segment indicating that the other node has initialized its device link segment. In an alternative initialization scheme, a node momentarily operates its data channel in a loopback mode to allow its end device to initialize the device link segment in accordance with a predetermined protocol before returning to a transparent mode.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: August 31, 2010
    Assignee: International Business Machines Corporation
    Inventors: Casimer M. DeCusatis, Thomas A. Gregg
  • Publication number: 20100178053
    Abstract: In an optical communications system in which an OLT transceiver and a plurality of ONU transceivers are connected to each other via an optical fiber and a TDMA system in which a signal from each of the ONU transceivers is issued at a timing assigned by the OLT transceiver is used, each of the ONU transceivers includes a light source which has modulation function of a Fabry-Perot laser that oscillates multi-mode lights of different wavelengths, the OLT transceiver includes a single-longitudinal-mode light source which has modulation function of a DFB laser that oscillates a single-longitudinal-mode light, and the light source which has modulation function included in each of the ONU transceivers and the single-longitudinal-mode light source which has modulation function included in the OLT transceiver are optically connected to each other via an optical fiber.
    Type: Application
    Filed: January 13, 2010
    Publication date: July 15, 2010
    Applicant: HITACHI, LTD.
    Inventors: Misuzu SAGAWA, Toshiki SUGAWARA
  • Patent number: 7751345
    Abstract: If exists a client signal of a bandwidth larger than “optical signal bandwidth BW” divided by “the number of utilizable ports P”, extracted is a combination(s) of signals including one or more of a signal of a maximum bandwidth, of signals of which a total bandwidth is within the BW and of signals of which the number of total ports required in correspondence with a protection type of each client signal is equal to P, and selected is a combination of which the total bandwidth is a maximum from among the extracted combinations.
    Type: Grant
    Filed: April 30, 2007
    Date of Patent: July 6, 2010
    Assignee: Fujitsu Limited
    Inventors: Tomohiro Hashiguchi, Toru Katagiri, Kazuyuki Tajima
  • Publication number: 20100166419
    Abstract: A method for performing a protection in passive optical networks. The method comprises forming a protection maintenance link between an active optical line terminal (OLT) and a standby OLT; forming a synchronization link between the active OLT and the standby OLT; computing a base differential distance value; continuously measuring round trip time (RTT) values by the active OLT using the protection maintenance link; periodically sending at least RTT values calculated by the active OLT to the standby OLT over the synchronization link; and computing, by the standby OLT, a new RTT value based on at least a RTT value measured by the active OLT and a standby differential distance value, when a switch-over action is triggered, thereby allowing the standby OLT to serve optical network units (ONUs) in the PON without performing a ranging process.
    Type: Application
    Filed: December 29, 2009
    Publication date: July 1, 2010
    Applicant: BROADLIGHT, LTD.
    Inventors: Eli Elmoalem, Amiad Dvir
  • Patent number: 7672585
    Abstract: Each of a plurality of semiconductor optical amplifiers operates as an optical gate switch and selects an optical signal indicated by a gate control signal from an optical gate switch control unit. A plurality of photodetectors monitor the power of an optical signal input through a corresponding input port. A VOA control unit calculates an amount of attenuation corresponding to each input port based on the power of each optical signal. A variable optical attenuator attenuates the selected optical signal according to the calculated amount of attenuation in synchronization with the gate control signal.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: March 2, 2010
    Assignee: Fujitsu Limited
    Inventors: Kyosuke Sone, Yasuhiko Aoki
  • Patent number: 7660527
    Abstract: In the case that a client signal having a bandwidth larger than BW divided by P exists, where the P is the number of client ports of one optical transponder card and the BW is an optical signal band, it is configured to accommodate client signals in one optical transponder card by combining plural client signals of which the total band is no greater than the BW and which have different bands so as to make it a maximum within the aforementioned range.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: February 9, 2010
    Assignee: Fujitsu Limited
    Inventors: Tomohiro Hashiguchi, Toru Katagiri, Kazuyuki Tajima
  • Publication number: 20090317080
    Abstract: The invention relates to a bandpass filter (OFI) which is mounted downstream of an optical amplifier (OV) and allows noise to be largely reduced. In order for said bandpass filter to be able to optimally receive burst signals (BS1, BS2, . . . , BSN) transmitted by several user devices (ONT1, ONT2, . . . , ONTN) also in a central node (OLT), the bandpass filter is set to the respective received carrier frequencies (TF1to TFN). Because of time constraints, this is possible only if the carrier frequencies (TF1, . . . ) or associated filter setting values (FE1, . . . ) have already been stored and the bandpass filter is preset.
    Type: Application
    Filed: July 11, 2007
    Publication date: December 24, 2009
    Applicant: NOKIA SIEMENS NETWORKS GMBH & CO. KG
    Inventor: Michael Rasztovits-Wiech
  • Patent number: 7603034
    Abstract: A telecommunications network component comprising: a processor configured to implement a method comprising: receiving an optical signal comprising at least one identification signal, the identification signal comprising a series of frequency portions that alternate in turn according to a frequency interval defined for each of the series of frequency portions, partitioning the identification signal by way of a plurality of windows, performing a Fast Fourier Transform (FFT) on each of the plurality of windows, determining which of the plurality of windows comprise a relative minimum number of frequency components, and detecting an optical channel based on results of the FFT performed on each of the plurality of windows that comprise the relative minimum number of frequency components.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: October 13, 2009
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Shuqiang Shen, Congqi Li
  • Patent number: 7555215
    Abstract: A dual structure for a multiplexing section extended to an OSU is obtained without adding a dynamic function, such as an optical switch, to a W-MULDEM. The W-MULDEM of an optical wavelength division multiplexing access system divides, among ports corresponding to the individual ONUs, downstream optical signals having wavelengths ?d1 to ?dn, which are received along a current-use optical fiber, or downstream optical signals having wavelengths ?d1+?? to ?dn+??, which are received along a redundant optical fiber. The W-MULDEM also multiplexes, for the port that corresponds to the current-use optical fiber or the redundant optical fiber, upstream optical signals having wavelengths ?u1 to ?un or wavelengths ?u1+?? to ?un+??, which are received along optical fibers corresponding to the ONUs. A wavelength difference between the downstream optical signal and the upstream optical signal that are consonant with each ONU is defined as an integer times the FSR of an AWG.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: June 30, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hirotaka Nakamura, Junichi Kani, Hiroo Suzuki, Mitsuhiro Teshima, Ukyo Yamaguchi, Hidetaka Onishi, Katsumi Iwatsuki
  • Publication number: 20090162055
    Abstract: An optical access system capable of avoiding cutoffs or interruption in the periodically transmitted signals that occur during the ranging time is provided. A first method to avoid signal cutoffs is to stop periodic transmit signals at the transmitter during the ranging period, and transmit all the periodic transmit signals together when the ranging ends, and buffer the signals at the receiver to prepare for ranging. A second method is to fix definite periods ahead of time for performing ranging, then cluster the multiple periodic transmit signals together in sets at the transmitter and send them, and then disassemble those sets back into signals at the receiver. The transmitting and receiving is then controlled so that the transmit periods do not overlap with the ranging periods. In this way an optical access system is provided that can send and receive signals requiring periodic transmissions without interruption even during ranging operation.
    Type: Application
    Filed: February 18, 2009
    Publication date: June 25, 2009
    Inventors: Kenichi Sakamoto, Yoshihiro Ashi, Tohru Kazawa, Ryosuke Nishino, Masayuki Takase, Masahiko Mizutani
  • Patent number: 7440694
    Abstract: An accurate method of reporting “minutes of outage” for a SONET facility applies a set of business rules and hierarchical definitions to delete certain minutes that would otherwise be counted as “outages”. In particular, any outage minutes reported for a network element taken out of service for “planned maintenance” activities are removed prior to performing the final count. Additionally, outage minutes for a “lower level” element (such as, for example an OC1 element) that overlap in time with outage minutes reported for a “high level” element are likewise removed before the count is performed. The elimination of these non-service impacting outage minutes thus results in a more accurate reporting of the actual service impact of the counted outage minutes.
    Type: Grant
    Filed: November 8, 2007
    Date of Patent: October 21, 2008
    Assignee: AT&T Corp.
    Inventors: Hossein Eslambolchi, Kerrie L. Linker, Alexander Novokshanov, Harold Jeffrey Stewart, Denis Sergeyevich Yankin
  • Publication number: 20080181604
    Abstract: An optical access system capable of avoiding cutoffs or interruption in the periodically transmitted signals that occur during the ranging time is provided. A first method to avoid signal cutoffs is to stop periodic transmit signals at the transmitter during the ranging period, and transmit all the periodic transmit signals together when the ranging ends, and buffer the signals at the receiver to prepare for ranging. A second method is to fix definite periods ahead of time for performing ranging, then cluster the multiple periodic transmit signals together in sets at the transmitter and send them, and then disassemble those sets back into signals at the receiver. The transmitting and receiving is then controlled so that the transmit periods do not overlap with the ranging periods. In this way an optical access system is provided that can send and receive signals requiring periodic transmissions without interruption even during ranging operation.
    Type: Application
    Filed: March 25, 2008
    Publication date: July 31, 2008
    Inventors: Kenichi Sakamoto, Yoshihiro Ashi, Tohru Kazawa, Ryosuke Nishino, Masayuki Takase, Masahiko Mizutani
  • Patent number: 7394824
    Abstract: In a system including a parent station and a plurality of child stations connected only to the parent station, which is unable to detect a response among the plurality of child stations, the parent station includes a transmission permission sequential allocation mechanism for giving transmission permission sequentially and a first timer for monitoring a first period which is a response detection time period. The child station includes a transmission permission detection mechanism for detecting that the identifier sent by the parent station is directed to the own station. Each of the child stations transmits data in a band period when the child station is permitted to communicate. When the parent station does not receive a response from the child station permitted to communicate within the first period, the parent station permits a next child station to communicate.
    Type: Grant
    Filed: May 16, 2002
    Date of Patent: July 1, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Toshihisa Hane
  • Patent number: 7228073
    Abstract: An optical signal transmission device for transmitting phase information of optical signals is provided. The device includes a multiplexing formatted optical signal generator arranged to generate multiplexing formatted optical signals. The device also includes an optical phase generator arranged to receive the multiplexing formatted optical signals. An optical information transmission method for transmitting optical signal information including phase information is also provided. The method includes receiving multiplexing formatted optical signals generated by a multiplexing formatted optical signal generator at an optical phase generator. The method also includes phase conjugating the multiplexing formatted optical signals by means of four wave mixing (FWM).
    Type: Grant
    Filed: July 9, 2003
    Date of Patent: June 5, 2007
    Assignee: National Institute of Information and Communications Technology, Incorporated Administrative Agency
    Inventors: Jun Inoue, Hideyuki Sotobayashi, Wataru Chujo, Hitoshi Kawaguchi
  • Patent number: 7174105
    Abstract: An all-optical time division multiplexing system, comprising: first divider having first input and a first plurality of outputs for receiving input signals at the first input and directing the input signals to each of the outputs of the first plurality of outputs, the input signals arranged within periodic time slots; second divider having second input and a second plurality of outputs for receiving clock signals at the second input and directing the clock signals to each of the outputs of the second plurality of outputs, and a third plurality of AND gates each having third and fourth inputs and fifth output for receiving the input signals at the third input from one of the outputs of the first plurality of outputs and receiving the clock signals at the fourth input from one of the outputs of the second plurality of outputs, and the clock signals and the input signals coincide in the third and fourth inputs of the AND gates of the third plurality of AND gates in a consecutive order to produce at the fifth
    Type: Grant
    Filed: October 15, 2003
    Date of Patent: February 6, 2007
    Assignee: Main Street Ventures LLC
    Inventor: Arie Shahar
  • Patent number: 7161964
    Abstract: A reconfigurable ADD/DROP multiplexer/demultiplexer apparatus is implemented by connecting a multiplexer/demultiplexer apparatus to a serializer/deserializer (SERDES) apparatus having a loop-back capability. By selectively activating the loop-back functionality of the SERDES apparatus the combination can be made to function as a reconfigurable ADD/DROP multiplexer/demultiplexer apparatus.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: January 9, 2007
    Assignee: Lucent Technologies Inc.
    Inventors: Anthony L. Lentine, Graham H. Smith, Ted K. Woodward
  • Patent number: 7092629
    Abstract: A data transmission system employs a method of aligning transmission lanes with reception lanes in a multiplexing arrangement. A plurality of control symbols and lane identifiers are transmitted on each of the transmission lanes. The transmission lanes are divided into groups for time-division multiplexing. Within the groups, the transmission lanes are time-division multiplexed and then wave-division multiplexed onto a data link. Upon reception, wave-division and time-division demultiplexing is conducted to extract groups of reception lanes corresponding to the groups of transmission lanes. One of the reception lanes in each group of reception lanes is monitored for receipt of a control symbol followed by a lane identifier. Upon receipt, the lane assignment of the reception lanes is rotated within the particular group if the received lane identifier does not match the identity of the reception lane being monitored.
    Type: Grant
    Filed: November 19, 2001
    Date of Patent: August 15, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: William P. Bunton
  • Patent number: 7085281
    Abstract: A protocol for an optical network can control the time at which subscriber optical interfaces of an optical network are permitted to transmit data to a transceiver node. The protocol can prevent collisions of upstream transmissions between the subscriber optical interfaces of a particular subscriber group. With the protocol, a transceiver node close to the subscriber can allocate additional or reduced upstream bandwidth based upon the demand of one or more subscribers. That is, a transceiver node close to a subscriber can monitor (or police) and adjust a subscriber's upstream bandwidth on a subscription basis or on an as-needed basis. The protocol can account for aggregates of packets rather than individual packets. By performing calculation on aggregates of packets, the algorithm can execute less frequently which, in turn, permits its implementation in lower performance and lower cost devices, such as software executing in a general purpose microprocessor.
    Type: Grant
    Filed: October 26, 2001
    Date of Patent: August 1, 2006
    Assignee: Wave7 Optics, Inc.
    Inventors: Stephen A. Thomas, Kevin Bourg, Deven Anthony, Patrick W. Quinn, James O. Farmer, John J. Kenny, Thomas A. Tighe, Paul F. Whittlesey, Emmanuel A. Vella