Time Division Patents (Class 398/98)
  • Patent number: 8463135
    Abstract: A relay apparatus including: a first interface 11 that branches an optical signal that is input in a first direction from one side of the optical transmission line, and directs the optical signal to a first path and a second path, the first path being a processing path of an optical signal having a first transmission speed, the second path being a processing path of an optical signal having a second transmission speed that is different from the first transmission speed; a processing section 12 that executes processing on an optical signal propagating through each of the paths in accordance with a corresponding transmission speed; and a second interface 13 that binds the first path and the second path of the optical signal on which the processing is executed by the processing section, by means of wavelength multiplexing and directs to the other end of the optical transmission line.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: June 11, 2013
    Assignee: Fujitsu Limited
    Inventors: Kyosuke Sone, Yutaka Kai, George Ishikawa, Susumu Kinoshita
  • Publication number: 20130136452
    Abstract: Methods, systems, and apparatuses for time-based composite modulation of an optical carrier signal are provided. Time-based composite modulation includes determining a plurality of fixed time slots for the optical carrier signal, wherein the plurality of fixed time slots comprise a time-division-multiplexing frame. Determining a modulation format for each fixed time slot of the time-division-multiplexing frame, wherein a transport spectral efficiency of the modulation format determined for a first fixed time slot is different from a transport spectral efficiency of the modulation format determined for a second fixed time slot, and determining a number of binary bits for each fixed time slot of the time-division-multiplexing frame, wherein the number of binary bits for a fixed time slot is based on the modulation format determined for the fixed time slot.
    Type: Application
    Filed: November 30, 2011
    Publication date: May 30, 2013
    Applicant: AT&T INTELLECTUAL PROPERTY I, LP
    Inventors: Xiang Zhou, Peter Magill
  • Patent number: 8412047
    Abstract: The polarization multiplexed light transmitter takes out a part of a polarization multiplexed light to be transmitted as a monitor light; makes orthogonal polarization components contained in the monitor light to interfere with each other, to generate a polarization interfering light; converts the polarization interfering light into an electric signal; measures the power of an alternate current component contained in the electric signal after eliminating a direct current component thereof; and feedback controls delay amount varying sections so that an inter-polarized channel delay time judged based on a change in the measured power reaches a predetermined value. Thus, the delay time between the orthogonal polarization components in the polarization multiplexed light can be varied flexibly at a high speed with a simple configuration, and thus, it becomes possible to suppress transmission characteristics degradation of the polarization multiplexed light due to a change in system state.
    Type: Grant
    Filed: September 4, 2009
    Date of Patent: April 2, 2013
    Assignee: Fujitsu Limited
    Inventors: Toshiki Tanaka, Yuichi Akiyama, Masahiro Yuki, Hideyuki Miyata
  • Patent number: 8406631
    Abstract: The subject matter disclosed herein relates to synchronizing network timing. In one particular example, network timing may be synchronized using reflected signals.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: March 26, 2013
    Assignee: Applied Optoelectronics, Inc.
    Inventor: Stefan J. Murry
  • Patent number: 8401401
    Abstract: To provide a polarization-diverse, heterodyne optical receiving system, a light signal is transmitted into an optical fiber having a plurality of optical sensors that are distinguishable using a multiplexing arrangement. A return light signal from the optical fiber is mixed with an optical local oscillator light signal, where the mixing outputs plural output signal portions having different polarizations. A birefringence of a particular optical sensor is determined based on the plural signal portions.
    Type: Grant
    Filed: October 14, 2009
    Date of Patent: March 19, 2013
    Assignee: Schlumberger Technology Corporation
    Inventors: Arthur H. Hartog, Dominic Brady, Maxwell R. Hadley
  • Patent number: 8396367
    Abstract: This invention concerns a high frequency optical processor suitable for time-division demultiplexing and channel dropping data signals at bit rates of 80-160 Gb/s and beyond, and for carving high frequency pulse streams with low duty cycle from an unmodulated laser source. In further aspects the invention concerns methods for using the high frequency optical processor. In particular the invention comprises a high frequency optical processor, comprising a Mach-Zehnder amplitude modulator (MZM) embedded in a fiber mirror loop in which the loop input and output are joined by a polarization maintaining coupler.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: March 12, 2013
    Assignee: The University of Sydney
    Inventor: Mark Pelusi
  • Patent number: 8391715
    Abstract: When a neighbor ONU receives a signal with light intensity high enough to secure communication between an OLT and a remote ONU, the light intensity may be excessively high to damage a receiver of the neighbor ONU. In order to avoid such a problem, each ONU is notified of a downstream signal transmission plan (downstream light intensity map) prior to transmission of a downstream signal. Each ONU receives the downstream light intensity map (light intensity transmission schedule of downstream signal) in advance. Thus, the neighbor ONU can block or attenuate an optical signal addressed to the remote ONU, and the remote ONU can determine normal operation even when the remote ONU cannot receive a signal addressed to the neighbor ONU. Thus, the remote ONU can be prevented from issuing a wrong error signal.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: March 5, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Masao Niibe, Masahiko Mizutani, Shinya Fujioka
  • Publication number: 20130051801
    Abstract: The invention describes a method and an arrangement for transmitting an optical transmission signal with reduced polarisation-dependent loss. A first transmission signal component and a second orthogonal transmission signal component of the optical transmission signal are transmitted with a time difference between said transmission signal components.
    Type: Application
    Filed: December 15, 2009
    Publication date: February 28, 2013
    Inventors: Maxim Kuschnerov, Bernhard Spinnler, Berthold Lankl, Antonio Napoli
  • Patent number: 8385744
    Abstract: A method for controlling delay in a Passive Optical Network (PON) is applicable when a Precision Timing Protocol (PTP) message is transmitted in a downlink direction. The method includes obtaining a buffer duration of the PTP message destined for an Optical Network Unit (ONU), storing the PTP message destined for the ONU, and sending the PTP message to the ONU when a duration for storing the PTP message reaches the buffer duration.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: February 26, 2013
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Jun Zhao
  • Patent number: 8355629
    Abstract: Methods, systems, and computer-readable media provide for notifying an optical line termination (OLT) of a power failure. According to embodiments, a method for notifying an OLT of a power failure is provided. According to the method, a notification of a power failure at an optical network termination (ONT) is received. In response to receiving the notification, power is retrieved from a dedicated power storage unit dedicated to providing power for the transmission of a dying gasp alarm. The dying gasp alarm is transmitted to the OLT utilizing at least a portion of the power from the dedicated power storage unit. The dying gasp alarm notifies the OLT of the power failure.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: January 15, 2013
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Glenn Mark Mahony, Mounire El Houmaidi
  • Publication number: 20130011142
    Abstract: An optical communication system comprises a network interface device (NID) having a media converter coupled to an optical fiber of a passive optical network (PON). The media converter converts optical signals from the PON into electrical signals for communication across at least one non-optical channel, such as a conductive or wireless connection, to customer premises equipment (CPE), such as a residential gateway or other customer premises (CP) device. Rather than implementing an optical media access control (optical MAC) layer in the NID, an optical MAC layer for handling PON protocols and management is implemented by the CPE, thereby effectively extending the customer end of the PON across at least one non-optical connection to the CPE. By implementing the optical MAC layer at the CPE, the complexity of the NID is reduced thereby lowering the cost of the NID.
    Type: Application
    Filed: July 7, 2011
    Publication date: January 10, 2013
    Inventors: Richard Goodson, Leif J. Sandstrom, Kevin W. Schneider
  • Patent number: 8346083
    Abstract: An optical line terminal calculates a requirement threshold for each optical subscriber unit based on a difference between the time average allocated bandwidth of each optical subscriber unit and the target bandwidth, and notifies a corresponding optical subscriber unit of the calculated requirement threshold. The corresponding optical subscriber unit then notifies, based on the data amount accumulated in a buffer, the optical line terminal of a data amount, as a transmission requirement, up to a data separation that is less or equal to the notified requirement threshold and in which a maximum transmission amount can be transmitted. The optical line terminal then notifies the corresponding optical subscriber unit of a transmission permission amount in which the data equal to the transmission requirement of which the optical line terminal is notified can be transmitted. The corresponding optical subscriber unit then transmits the data amount corresponding to the transmission permission amount.
    Type: Grant
    Filed: February 17, 2009
    Date of Patent: January 1, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Daisuke Murayama, Noriyuki Oota, Noriki Miki
  • Patent number: 8340521
    Abstract: An optical transmission system is provided. The optical transmission system includes a user side optical repeater device, a central office side optical repeater device, and wavelength multiplexing and wavelength de-multiplexing functions. The user side optical repeater device is to be connected with a user side optical network unit, transmits data in two ways, and is used for wavelength division multiplexing. The central office side optical repeater device is to be connected with a central office side optical line terminal, transmits data in two ways, and is used for wavelength division multiplexing. The wavelength multiplexing and wavelength de-multiplexing functions are used for relaying between the user side optical repeater device and the central office side optical repeater device.
    Type: Grant
    Filed: April 14, 2010
    Date of Patent: December 25, 2012
    Assignee: Furukawa Electric Co., Ltd.
    Inventor: Masayuki Miura
  • Publication number: 20120315048
    Abstract: A base station includes an antenna, a radio transceiver, an optical splitter, an optical-to-electrical converter, and a computation module. The antenna may be mounted to a tower and may be configured to receive an RF signal. The radio transceiver may be coupled to the antenna and mounted near the top of the tower. The transceiver may be configured to convert the RF signal to a baseband signal for transmission over a fiber optic link as a first optical signal. The splitter may be configured to split the first optical signal, received via the fiber optic link, into a second optical signal and a third optical signal. The optical-to-electrical converter may be configured to convert the second optical signal into an electrical digital signal including in-phase and quadrature (I/Q) data. The computation module may be configured to compute, based on the I/Q data, signal measurements for location of a mobile station.
    Type: Application
    Filed: April 10, 2012
    Publication date: December 13, 2012
    Applicant: Andrew, LLC
    Inventors: Andrew E. Beck, Thomas B. Gravely, Carmine J. Pagano, II
  • Patent number: 8331788
    Abstract: According to one general aspect, a method may include receiving, from an optical transmitter, an optical signal that includes information. In some embodiments, the method may include encapsulating at least a portion of the received information into an Ethernet packet. In various embodiments, the method may include associating a control word with the Ethernet packet. In such an embodiment, the control word may include a status portion that indicates a status of at least a portion of the network including the networking apparatus, and an ordinal number configured to facilitate the re-construction of the information included by the optical signal. In various embodiments, the method may include transmitting the Ethernet packet to a networking apparatus.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: December 11, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Gilberto Loprieno, Luca Della Chiesa, Davide Codella
  • Patent number: 8315523
    Abstract: When a frame is received from one of PON ports 12a to 12c of ONUs 1a to 1c, an OLT 3 compares VPIDs contained in Preamble/SFD regions A of the received Ethernet® frame with VPIDs assigned to LAN ports 31 and 32 of the OLT 3. Upon coincidence, a PON MAC process is started. When a frame is received from a PON port 33 of the OLT 3, each of the ONUs 1a to 1c compares a VPID contained in a Preamble/SFD region of the received Ethernet® frame with VPIDs assigned to the ONUs 1a to 1c. Upon coincidence, a PON MAC process is started.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: November 20, 2012
    Assignee: NEC Corporation
    Inventor: Sadaichiro Ogushi
  • Publication number: 20120281985
    Abstract: A transmitting apparatus includes a frame dividing circuit that maps frame data of each of a plurality of frames whose period is different from each other into one or a plurality of internal frames having a fixed frame period and a fixed transmission rate, based on a predetermined internal clock; a cross-connect circuit that cross-connects the frame data of each in a time division multiplexing system based on the internal clock in units of the internal frames; and a frame combining circuit that demaps, into any of the plurality of frames, or multiplexes, data of one or a plurality of internal frames cross-connected by the cross-connect circuit.
    Type: Application
    Filed: May 3, 2012
    Publication date: November 8, 2012
    Applicant: FUJITSU LIMITED
    Inventors: Hiroyuki HONMA, Masahiro Shioda, Toru Katagiri
  • Publication number: 20120269512
    Abstract: Aspects of the invention provide transmitters and receivers for managing multiple optical signals. High order modulation, such as phase and/or amplitude modulation, is used to achieve multiple bits per symbol by transporting multiple asynchronous data streams in an optical transport system. One or more supplemental multiplexing techniques such as time division multiplexing, polarization multiplexing and sub-carrier multiplexing may be used in conjunction with the high order modulation processing. This may be done in various combinations to realize a highly spectrally efficient multi-data stream transport mechanism. The system receives a number of asynchronous signals which are unframed and synchronized, and then reframed and tagged prior to the high order modulation. Differential encoding may also be performed. Upon reception of the multiplexed optical signal, the receiver circuitry may employ either direct detection without a local oscillator or coherent detection with a local oscillator.
    Type: Application
    Filed: April 19, 2011
    Publication date: October 25, 2012
    Applicant: GOOGLE INC.
    Inventors: Bikash Koley, Vijayanand Vusirikala, Hong Liu
  • Patent number: 8295705
    Abstract: A time-sharing Visible Light Communication (VLC) system is provided. Two or more light sources transmit data received from one or more VLC terminals located in its service area to a communication control device, and transmits data received from the communication control device to the one or more VLC terminals. The communication control device determines and groups at least one of the two or more light sources to be included in a cell according to a generated user service, maps the grouped at least one light source to the cell, allocates a time slot used to provide the user service to the cell, transmits data associated with the user service to at least one of the one or more VLC terminals through the at least one light source mapped to the cell using the allocated time slot, detects a location of the at least one VLC terminal located in a service area of the cell on a real-time basis, and remaps the cell according to the detected location.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: October 23, 2012
    Assignee: Samsung Electronics Co., Ltd
    Inventors: Do-Young Kim, Dae-Seok Kim, Eun-Tae Won
  • Publication number: 20120257900
    Abstract: A timing interface module installs within a rack to increase bandwidth. The timing interface module receives a reference timing signal and outputs the reference timing signal to an optical multiplexer. The optical multiplexer also receives multiple data streams of different formats, and the optical multiplexer synchronizes the multiple data streams to the reference timing signal.
    Type: Application
    Filed: June 22, 2012
    Publication date: October 11, 2012
    Applicant: AT&T INTELLECTUAL PROPERTY I, L.P.
    Inventors: Stephen H. Culpepper, Jack C. Martin, JR.
  • Patent number: 8270837
    Abstract: A device capable of equalizing optical powers of optical signals in a passive optical network, the device comprising a first optical coupler for receiving optical signals having different optical power levels, an optical circulator capable of directing the optical signals from the first optical circulator, a laser diode capable of generating equalized optical signals having a predetermined range of optical power levels in response to the optical signals directed from the optical circulator, and a second optical coupler for receiving the equalized optical signals.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: September 18, 2012
    Assignee: Industrial Technology Research Institute
    Inventors: Chien-Hung Yeh, Dar-Zu Hsu, Sien Chi
  • Publication number: 20120224858
    Abstract: A method and an apparatus for transmitting multiple services are provided, and which belong to the field of optical transmission technologies. The method includes: receiving bandwidth information of TCONTs of all nodes; dividing a payload area of a GTH frame into a preset number n of arrays, where each array includes a specified number of timeslots and the interval between any two neighboring timeslots in each array is n and n is a natural number; calculating, according to the bandwidth information of the TCONTs of all the nodes, timeslot positions of arrays occupied by the TCONTs of each node in the payload area; interleaving, according to the timeslot positions of the arrays occupied by the TCONTs of a local node in the payload area, the TCONTs of the local node into corresponding timeslots starting from a specified frame, obtaining a GTH frame, and transmitting the GTH frame.
    Type: Application
    Filed: May 10, 2012
    Publication date: September 6, 2012
    Applicant: Huawei Technologies Co., Ltd.
    Inventors: Zhiyun Chen, Xing Hu, Min Yan, Jianlin Zhou, Yang Cao, Kun Li
  • Publication number: 20120224857
    Abstract: A bandwidth adjusting method and a communication node are provided. The adjusting method includes: sending, by an upstream ingress unit, a group of multi-channel parallel basic switch cells in which adjustment signaling is carried to all downstream branch egress units; sending normal signaling when determining that adjustment response statuses returned by all the downstream branch egress units are reception acknowledgment; after receiving the normal signaling by the downstream branch egress unit, adding or removing the basic switch cell into or from a next group of multi-channel parallel basic switch cells according to the adjustment signaling; and adjusting a time slot of an HO ODU sent by the downstream branch egress unit to a downstream node, and instructing the downstream node to adjust the time slot of the HO ODU. Through the method and the communication node, lossless bandwidth adjustment in a point-to-multipoint OTN asymmetric bandwidth carrier system is implemented.
    Type: Application
    Filed: May 4, 2012
    Publication date: September 6, 2012
    Applicant: Huawei Technologies Co., Ltd.
    Inventors: Wei Su, Huaping Qing, Xi Huang, Chiwu Ding
  • Publication number: 20120207480
    Abstract: A control section and a signal detection section of an optical modulator are provided for controlling two interferometers (MZI1 and MZI 2) and a phase shifter (MZI 3) of an optical modulator. The signal detection section detects signals having the same frequency, and the control section of the optical modulator time-divides the detected signal so that a DC bias is optimally adjusted. In addition, a process is divided into an initial operation flow and a repeating operation flow so as to further improve the control efficiency of the optical modulator. An initial state control of the optical modulator and a state control during operations are performed through the respective flows. An optimal DC bias position used to control the optimal modulator is automatically corrected.
    Type: Application
    Filed: January 27, 2012
    Publication date: August 16, 2012
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Jyung Chan LEE, Hwan Seok CHUNG
  • Patent number: 8244135
    Abstract: A system, method, and computer readable medium for increasing an upstream optical coding gain in a passive optical network (PON). In an exemplary embodiment of the invention, the system may include a memory structured to store Optical Network Terminator (ONT) burst timing values, and provide a previous burst timing value of the burst timing values to a translator. Further, an upstream burst grant timing scheduler may provide a scheduled timing value to the translator, wherein the translator may be structured to translate the previous burst timing value to a new expected timing value per an ONT upstream burst in association with the scheduled timing value. Also, a delimiter match and search block may be structured to use the new expected timing value to check a bit stream for a delimiter pattern match. An alarm counter may be provided in the system that is structured to provide an alarm when the delimiter pattern match is not found.
    Type: Grant
    Filed: November 19, 2008
    Date of Patent: August 14, 2012
    Assignee: Alcatel Lucent
    Inventors: James J Stiscia, Jihad Baghdadi
  • Patent number: 8238752
    Abstract: A PON station side apparatus is provided with a selection section and a receiving section. For multiple data transferred from multiple PON terminal apparatuses that transmit data at different communication speeds in time division multiplexing, the selection section selects any of the multiple receiving circuits to be a receiving circuit for a receiving destination at which data is received on the basis of the transmission time zones for the data. The receiving section switches the receiving circuit selected by the selection section among the multiple receiving circuits to be the receiving circuit for the destination at which data is received of the data and receives the data through the switched receiving circuit.
    Type: Grant
    Filed: January 29, 2009
    Date of Patent: August 7, 2012
    Assignee: NEC Corporation
    Inventor: Sadaichirou Ogushi
  • Patent number: 8238556
    Abstract: A quantum communication system comprising a sending unit and a receiving unit, said sending unit comprising a photon source assembly configured to output a stream of pulses of light having at least two different intensities and a memory configured to store information for determining which pulses should be reference pulses and which pulses should be data pulses, the average intensity of reference pulses being different to the average intensity of data pulses, the receiving unit comprising a memory for storing information for identifying the position of reference pulses within the stream of pulses and a processor for determining the calibration of the quantum communication system from the reference pulses.
    Type: Grant
    Filed: September 8, 2006
    Date of Patent: August 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Zhiliang Yuan, Andrew James Shields
  • Patent number: 8233800
    Abstract: According to one embodiment of the invention, a method for providing communications service in a communications ring undergoing an upgrade process includes increasing an existing rate of a node to a higher rate. With the increase, the node is operable to transmit a second frame at the higher rate. The second frame has a higher number of time slots than a first frame having a number of slots equal to N. The method also includes occupying a number of the time slots of the second frame equal to N using data to be received by an existing node. The method also includes providing at least one identifier to the existing node that will receive the second frame. The identifier identifies the occupied time slots of the second frame. The method also includes transmitting the second frame of data to the existing node.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: July 31, 2012
    Assignee: Fujitsu Limited
    Inventors: Larry Henry Steinhorst, Wilson kit-man Chan, Junji Yamamoto
  • Patent number: 8233796
    Abstract: A timing interface module with daughter timing reference modules. The timing modules are provided in a rack platform to eliminate routing problems and which is compliant with all relevant industry standards. The timing reference module includes a face plate having first and second substantially rectangular openings, the face plate further comprising mounting slots for receiving mounting hardware therein and first and second timing modules, the first and second timing modules disposed within the first and second substantially rectangular openings. The first and second timing modules provide timing terminations for timing reference signals for network elements of a synchronized optical network.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: July 31, 2012
    Assignee: AT&T Intellectual Property I, L. P.
    Inventors: Stephen Culpepper, Jack C. Martin, Jr.
  • Publication number: 20120183296
    Abstract: A multiport passive optical signal sharing device enabling optical signals received by each of a first plurality of ports of the device to be transmitted to all of the ports of a second plurality of ports of the device. The device includes a first coupling mechanism adapted to combine signals received by each port of the first plurality of ports of said device into a first optical signal, the first optical signal being transmitted over a bi-directional optical link. The device further includes a second coupling mechanism and guide for redirecting the first optical signal in a form of a second optical signal into the bi-directional optical link, in the opposite direction from that of the first optical signal, the first coupling mechanism being adapted to duplicate the second optical signal on each port of the second plurality of ports of the device.
    Type: Application
    Filed: September 7, 2010
    Publication date: July 19, 2012
    Applicant: AIRBUS OPERATIONS (S.A.S.)
    Inventors: Juan Lopez, Sabastien Delorge, Alexandre Touya
  • Patent number: 8224183
    Abstract: A method and apparatus for implementing a hybrid SOA-Raman amplifier in a central office in order to enable multiple passive optical networks to share one or more enhancement service sources, e.g., to share a source for a broadcast service are disclosed.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: July 17, 2012
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Patrick Paul Iannone, Han Hyub Lee, Kenneth Charles Reichmann, Xiang Zhou
  • Publication number: 20120177374
    Abstract: A quantum communication system including a sending unit and a receiving unit, said sending unit comprising a photon source assembly configured to output a stream of pulses of light having at least two different intensities and a memory configured to store information for determining which pulses should be reference pulses and which pulses should be data pulses, the average intensity of reference pulses being different to the average intensity of data pulses, the receiving unit comprising a memory for storing information for identifying the position of reference pulses within the stream of pulses and a processor for determining the calibration of the quantum communication system from the reference pulses.
    Type: Application
    Filed: March 16, 2012
    Publication date: July 12, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Zhiliang Yuan, Andrew James Shields
  • Publication number: 20120155880
    Abstract: An optical modulator includes: a modulator including an optical waveguide provided in a semiconductor substrate having an electro-optical effect and an electrode to apply an electric field depending on a bias voltage and a modulation signal to the optical waveguide; a driver circuit to generate a modulation signal in accordance with an input signal; a superimposer to superimpose a reference signal on the bias voltage, the reference signal having lower frequency than the modulation signal; and a controller to control a bias voltage in a direction orthogonal to a modulation direction of the modulator based on the frequency component of the reference signal extracted from a modulated optical signal generated by the modulator.
    Type: Application
    Filed: December 12, 2011
    Publication date: June 21, 2012
    Applicant: Fujitsu Optical Components Limited
    Inventors: Hiroshi Nishimoto, Hiroshi Kuwahara
  • Publication number: 20120155882
    Abstract: The disclosure relates to optical fiber transmission systems, and in particular, pertains to the transceiver cards in an optical fiber transport system. In particular the disclosure teaches an improved transceiver card architecture that allows high density, flexibility and interchangeability of functionality.
    Type: Application
    Filed: February 27, 2012
    Publication date: June 21, 2012
    Inventors: Samir Satish Sheth, Marvin R. Young, Jeffrey Lloyd Cox, John W. Ayres, III
  • Patent number: 8200083
    Abstract: An apparatus comprising an individual optical power level calculation (IOPLC) module and a transceiver coupled to the IOPLC module and configured to communicate with a plurality of optical network units (ONUs). Also disclosed is an apparatus comprising a control and management (CM) module, an average power level measurement (APLM) module coupled to the CM module, a first transceiver coupled to the CM module and configured to communicate with an optical line terminal (OLT), and a second transceiver coupled to the CM module and the APLM module, and configured to communicate with a plurality of ONUs.
    Type: Grant
    Filed: November 24, 2008
    Date of Patent: June 12, 2012
    Assignee: Futurewei Technologies, Inc.
    Inventors: Frank J. Effenberger, Yin Jinrong, Yang Sulin
  • Patent number: 8195049
    Abstract: System and methods are provided, in an Optical Transport Network (OTN), for communicating asynchronous Tributary Slots (TSs) via a synchronous Optical Payload Transport Unit of level k (OTUk) interface. The transmission method accepts a plurality of TSs at a corresponding plurality of asynchronous data rates. The TSs are mapped, using a tangible memory medium, into pseudo-Optical channel Data Tributary Unit (ODTU) frames synchronized to a common clock. Then, the synchronized pseudo-ODTU frames can be interleaved into an OTUk frame, without the need of a phase-locked loop (PLL) or buffering.
    Type: Grant
    Filed: September 27, 2011
    Date of Patent: June 5, 2012
    Assignee: Applied Micro Circuits Corporation
    Inventors: Glen Miller, Tracy Xiaoming Ma
  • Publication number: 20120134677
    Abstract: The present invention discloses a method and system for transferring TDM services in GPON, the method includes the steps of: in the case of performing the GPON ranging process, buffering the uplink TDM service data received by an optical signal transceiver in an Input Buffer, reading out and transferring the uplink TDM service data buffered in an Output Buffer. The present invention eliminates the possible interruption of TDM services during the GPON ranging process by buffering the uplink services at the OLT and ONU/ONT side and relevant processes, and therefore realizes the TDM service transmission without any loss during the GPON system ranging process.
    Type: Application
    Filed: December 29, 2011
    Publication date: May 31, 2012
    Applicant: Huawei Technologies Co., Ltd.
    Inventors: Yan Xiong, Jun Zhao, Wanwan Wang
  • Publication number: 20120128363
    Abstract: The present invention discloses an device for cross protection, including: a service unit source end, configured to map optical data unit (ODUk) signals into the same time slots of n line similar optical transport network (OTN) frame format (OTUxG) data buses, and obtain m+n line OTUxG data through protective coding and then send to a combination cross unit; the combination cross unit, configured to split and recombine the m+n line OTUxG data in the time slot, and then send to a service unit destination end; the service unit destination end, configured to protectively decode the m+n line OTUxG data, recover n line OTUxG data, and extract corresponding ODUk signals from the same time slots of n line OTUxG data.
    Type: Application
    Filed: November 24, 2009
    Publication date: May 24, 2012
    Applicant: ZTE CORPORATION
    Inventors: Wenkai Ma, Yan Yuan
  • Patent number: 8184977
    Abstract: In a GPON system conforming to ITU-T Recommendations G.984.3, an optical line terminal is provided which has an active bandwidth allocation function that preferentially puts small bandwidth signals in a particular segment of a frame, e.g., at a head of the frame, to prevent fragmentations that may occur particularly when allocating small bandwidths of about 100 kbits/s.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: May 22, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Kazawa, Kenichi Sakamoto, Ryosuke Nishino
  • Patent number: 8180223
    Abstract: In accordance with the teachings of the present invention, a system and method for extending reach in a passive optical network (PON) is provided. In a particular embodiment, a method for extending reach in a PON includes transmitting traffic at a first wavelength from a transmitter at a first optical network unit (ONU) in a PON and transmitting traffic at a second wavelength from a transmitter at a second ONU in the PON. The method also includes receiving the traffic in the first wavelength at a first input port of a multiplexer at a distribution node in the PON and receiving the traffic in the second wavelength at a second input port of the multiplexer at the distribution node. The method further includes forwarding the traffic in the first wavelength and the traffic in the second wavelength to an optical line terminal (OLT) in the PON.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: May 15, 2012
    Assignee: Fujitsu Limited
    Inventors: Martin Bouda, Stephen A. Smith
  • Patent number: 8139950
    Abstract: A passive optical network system (PON) has a plurality of OLTs and ONUs with different transmission rates. OLTs with different transmission rates share information of priority frames and destinations, and determine timing for frame transmission to ONUs so that the signal from each of the OLTs does not collide when multiplied in a splitter. OLTs transmit the data to the ONU as a burst signal to prevent the signals with different rates from colliding. ONU acquires the information of the following burst frames. ONU receives only the signal addressed to the own ONU or with the transmission rate of own ONU, therefore errors in ONUs can be avoided. OLT receives only the signal with the transmission rate of own OLT from ONUs based on the transmission timing from the ONUs shared by the line terminators, errors in OLTs can be avoided.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: March 20, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Masao Niibe, Tohru Kazawa, Yusuke Yajima, Takeshi Kiyose, Masahiko Mizutani
  • Patent number: 8130782
    Abstract: A passive optical network including: a parent station OLT (optical line terminal); and a plurality of child stations ONU (optical network terminating unit), wherein the parent station and the plurality of child stations transmit an upstream frame and a downstream frame to each other, and the parent station includes means for generating a maintenance signal indicating failure at a mini slot, corresponding to each of the plurality of child stations, on a basis of a receiving state of a signal at the mini slot sent from each of the plurality of child stations.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: March 6, 2012
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshihiro Asashiba, Toshikazu Yoshida, Hiroaki Mukai, Seiji Kozaki
  • Publication number: 20120051751
    Abstract: The described implementations relate a Passive Optical Network (PON). In one implementation, the PON includes an Optical Network Unit (ONU) that has at least one transmitter subsystem component and an associated optical transmitter. The at least one transmitter subsystem component may be configured to be in an enabled state during a timeslot period assigned to the ONU for transmitting an upstream data burst and a disabled state after the timeslot ends.
    Type: Application
    Filed: June 28, 2011
    Publication date: March 1, 2012
    Inventors: Armin PITZER, Anthony SANDERS, Christian JENKNER
  • Patent number: 8126333
    Abstract: An OLT includes a first transmitter and receiver unit for transmitting and receiving signals with ONUs, a first communication control timer, a measurement unit for measuring a round trip time (RTT) between the OLT and each of ONUs, an advance notice time generation unit for generating an advance notice time signal by adding a predetermined time to a time information that indicates a time in the first communication control timer in response to a first time reference pulse, and a unit for controlling the first transmitter and receiver unit to transmit the generated advance notice time signal to each of the ONUs, and to transmit signals indicating measured RTT/2 to the respective ones of the ONUs.
    Type: Grant
    Filed: May 26, 2009
    Date of Patent: February 28, 2012
    Assignee: KDDI Corporation
    Inventor: Yukio Horiuchi
  • Patent number: 8126328
    Abstract: A communication apparatus time-division multiplexes a first signal transmitted at a first bit rate and a second signal transmitted at a second bit rate which is an integer multiple of the first bit rate, and sends out the first signal and the second signal to one line. The communication apparatus includes a pulse generating unit and a pulse superimposing unit. The pulse generating unit generates repetitive pulses having a width equal to a width of the first signal. The pulse superimposing unit superimposes the pulses generated by the pulse generating unit on the second signal.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: February 28, 2012
    Assignee: Fujitsu Limited
    Inventor: Yukito Tsunoda
  • Publication number: 20120045213
    Abstract: There is provided a time division multiplexing transmission system which is capable of increasing the transmission efficiency. The system comprises OLT 10 and ONUs 20 connected to the OLT on a point-to-multipoint basis. The OLT 10 comprises a transmission circuit 11 that transmits a signal to the ONUs 20, a receiving circuit 12 that receives a signal from the ONU, and a transmission and receiving control circuit 13 that controls transmission and reception of a signal by the circuit 11 and the circuit 12. The OLT 10 specifies the transmission speed of an ONU device to be connected with itself, transmits the specified transmission speed to the ONU devices, and changes the settings of the circuit 12 based on that transmission speed. The ONU 20 transmits a response frame to the circuit 12 when the transmission speed transmitted from the circuit 11 agrees with its own transmission speed.
    Type: Application
    Filed: February 15, 2010
    Publication date: February 23, 2012
    Applicant: Furukawa Electric Co., Ltd.
    Inventor: Masayuki Miura
  • Publication number: 20120045214
    Abstract: Provided is an optical line terminator (OLT) to recover packet data and a clock from an optical signal including a silent interval. The OLT may receive packet data and a clock from at least one optical network unit (ONU). Even in a silent interval in which the at least one ONU does not transmit packet data, the OLT may successfully recover the clock.
    Type: Application
    Filed: August 19, 2011
    Publication date: February 23, 2012
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Mun Seob LEE, Dong Soo LEE, Geun Yong KIM, Hark YOO, Young Suk LEE, Sung Chang KIM, Jai Sang KOH, Jong Deog KIM
  • Patent number: 8116632
    Abstract: A space-time division multiple-access (STDMA) laser communications (lasercom) system and related techniques. The STDMA system includes a plurality of remote nodes and an STDMA access node which uses precise electronic beam steering and beacons to provide access to each of a plurality of remote access nodes by means of both space and time-division multiple access.
    Type: Grant
    Filed: November 26, 2008
    Date of Patent: February 14, 2012
    Assignee: Raytheon Company
    Inventors: William J. Miniscalco, Robert D. O'Shea, Irl W. Smith, Howard L. Waldman
  • Publication number: 20120027413
    Abstract: A method and apparatus for transmission of data on bandwidth limited fiber optic channels. A multilevel signaling alphabet having multiple levels of optical intensity are used to transmit signals on optical channels. In order to counteract the decrease in signal to noise ratio resulting from the use of a multilevel signaling alphabet over a bilevel signaling alphabet trellis encoding of the data to be transmitted is employed. To counteract intersymbol interference due to signaling faster than the Nyquist Rate, equalization methods such as Tomlinson-Harashima preceding and decision feedback equalization are employed.
    Type: Application
    Filed: July 14, 2011
    Publication date: February 2, 2012
    Inventor: Oscar E. Agazzi
  • Patent number: 8107819
    Abstract: An optical network device of a passive optical network is introduced. The optical network device includes a light source, a control unit, and a variable optical attenuator. The light source can generate an optical signal. The control unit can generate a magnetic signal based on a control signal capable of providing information relating to a distance between the optical network device and an optical line termination. The variable optical attenuator can adjust a polarization angle of the optical signal based on the magnetic signal.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: January 31, 2012
    Assignee: Industrial Technology Research Institute
    Inventors: Chun-Liang Yang, Dar-Zu Hsu