Time Division Patents (Class 398/98)
  • Patent number: 8107814
    Abstract: Upstream data handling in a digital Data Over Cable Service Interface Specification (DOCSIS) passive optical network (DPON). Embodiments include receiving at a headend, in an upstream path over an optical network, a plurality of digitized and serialized DPON upstream packets respectively distributed in a time division multiplexed fashion, wherein each DPON upstream packet includes a header, a trailer and a payload, monitoring the optical network for energy in the upstream path, including energy associated with a header and a trailer of respective DPON upstream packets, controlling a bit stuffer that adds bits to the upstream path to (1) stop adding bits to the upstream path when energy is detected in the upstream path and (2) resume adding bits to the upstream path after an end of a trailer of a given DPON upstream packet has been detected, and removing the header and the trailer of the respective DPON upstream packets.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: January 31, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Thai-Bao H. Kien, Amin Farvez, Richard J. Futch, Richard T. Causey, Michael Jones
  • Publication number: 20120002965
    Abstract: It is disclosed a method for data transmission in an optical transport network, comprising the steps of receiving client data from a client, mapping said client data into a frame structure (ODU-flex), mapping said frame structure (ODU-flex) into tributary slots (TS) of a data transport structure (HO-ODU), transmitting said data transport structure (HO-ODU), wherein said data transport structure (HO-ODU) contains a fixed number of tributary slots (TS), and wherein the size of said frame structure (ODU-flex) is selectable in granularity of said tributary slots (TS) of said data transport structure (HO-ODU).
    Type: Application
    Filed: March 9, 2010
    Publication date: January 5, 2012
    Inventors: Alberto Bellato, Pietro Vittorio Grandi, Matteo Gumier, Sergio Belotti, Stephen John Trowbridge
  • Patent number: 8081877
    Abstract: A method of determining an optical distance between two nodes of an optical network for chromatic dispersion compensation includes using existing optical supervisory channel components in each node to measure the “time-of-flight” of an optical signal having a known wavelength. The effective optical distance is determined based on the time-of-flight and known wavelength of the optical signal. The computed optical distance may then be used to compensate for the dispersion experienced by the optical signal when transmitted between the two nodes. Advantageously, the method allows tunable dispersion compensation of a wavelength channel to be periodically optimized at each node in response to incremental changes in environmental factors that affect the chromatic dispersion produced between the two nodes or in response to reconfigurations that affect the chromatic dispersion produced between the two nodes.
    Type: Grant
    Filed: May 8, 2008
    Date of Patent: December 20, 2011
    Assignee: Oclaro (North America), Inc.
    Inventors: Xiaodong Duan, Giovanni Barbarossa
  • Patent number: 8078058
    Abstract: The present invention relates to an adaptive and all-optical method for data packet rate multiplication compatible with multiple data rates and/or multiple communication protocols. By performing a real-time pulse width compression on an original electronic or optical packet from an end user or a network interface device, the method generates an optical packet having an identical rate with the original packet while the duration of each pulse being significantly reduced. Then, by eliminating any redundant idle time due to the pulse width compression, the method also shortens data period and thus makes the rate of packet multiplied. The present invention addresses the technical problem of limited data rate in EO/OE conversion as known in the prior art and solves fundamentally the interconnection and communication between networks or systems of different data rates and/or protocols.
    Type: Grant
    Filed: April 13, 2007
    Date of Patent: December 13, 2011
    Assignee: Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences
    Inventors: Jianguo Zhang, Wei Zhao, Xiaoping Xie
  • Publication number: 20110299853
    Abstract: A clock at a first network element that is connected to a second network element over an optical fiber link is aligned using bursts of timing information exchanged between the two network elements. According to one method, the bursts from the first network element to the second network element and the bursts from the second network element to the first network element are transmitted over the same wavelength channel of the optical fiber link, in which case zero asymmetry in the transit delays can be assumed during the alignment procedure. According to another method, the bursts from the first network element to the second network element and the bursts from the second network element to the first network element are transmitted over different wavelength channels of the optical fiber link, in which case the asymmetry in the transit delays can be quantified and applied during the alignment procedure.
    Type: Application
    Filed: July 13, 2010
    Publication date: December 8, 2011
    Inventors: George P. ZAMPETTI, Sanjay MANI
  • Patent number: 8068734
    Abstract: Embodiments of the present invention provide a systems, devices, and methods in which a client signal is divided into a plurality of channels, mapped within transport frames, and combined into a WDM transport signal. These embodiments include intra-nodal redundancy that protects against failure events within the transport transmitter. In particular, redundancy is provided within a network transport transmitter such that redundant paths are available so that electrical channels may be routed around a malfunctioning component within the transmitter.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: November 29, 2011
    Assignee: Infinera Corporation
    Inventor: Ting-Kunag Chiang
  • Patent number: 8068731
    Abstract: A dynamic bandwidth allocation method of an Ethernet passive optical network, comprises a predictor and a rule of QoS-promoted dynamic bandwidth allocation (PQ-DBA); the predictor predicts a client behavior and numbers of various kinds of packets by using a pipeline scheduling predictor consisted of a pipelined recurrent neural network (PRNN), and a learning rule of the extended recursive least squares (ERLS); the present invention establishes a better QoS traffic management for the OLT-allocated ONU bandwidth and client packets sent by priority.
    Type: Grant
    Filed: April 7, 2009
    Date of Patent: November 29, 2011
    Assignee: Chunghwa Telecom Co., Ltd.
    Inventors: Jan-Wen Peng, Hsing-Yi Wu, Chung-Ju Chang
  • Patent number: 8064773
    Abstract: An optical fiber communications apparatus comprises a housing provided with a motherboard and a plurality of modular cards , each of which is engageable with the motherboard via one of the card receptors. A optical card includes an optical transceiver for communication using a digital, optical communications signal over a single optical fiber link. Each modular card is provided with a plurality of circuit sub-assemblies, each circuit sub-assembly being configured for digital communication with a respective local audio, video or data electronic device via a respective connector using a respective electronic information-carrying signal. Each circuit sub-assembly is configured for communication of an audio, video or data information-carrying signal with the transceiver using the digital, optical communications signal.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: November 22, 2011
    Assignee: Emcore Corporation
    Inventors: Alon Dagan, Fred Sather
  • Publication number: 20110280581
    Abstract: A method of operating a high-output-power fiber laser system includes: time multiplexing a plurality of pulses, each pulse having a pulse width, and each having a different wavelength from a plurality of seed oscillators onto a single fiber; setting each pulse width to a width less than the phonon lifetime; separating in time each pulse from each other pulse so as to leave a gap between adjacent pulses; setting a time between pulses each having a common wavelength to a time longer than a round-trip time of flight through a fiber amplifier of pulses having the common wavelength; and injecting the plurality of pulses from the single fiber into the fiber amplifier. Also to disclosed is a system capable of performing the method.
    Type: Application
    Filed: May 12, 2010
    Publication date: November 17, 2011
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Bien Chann, Steven J. Augst, Tso Yee Fan, Antonio Sanchez-Rubio
  • Patent number: 8059961
    Abstract: A customer premises optical network unit (ONU) comprises: an electrical/optical transform unit 6 to be connected with an optical transmission path 2 at a central office side for performing an opto-electrical transform and an inverse opto-electrical transform; an ONU function part 7 to be connected with an electric signal input and output terminal of the electrical/optical transform unit 6; a serial/parallel transform unit 8 to be connected with a parallel signal terminal of the ONU function part 7 for performing a serial/parallel transform and an inverse serial/parallel transform; and a multi source agreement interface module 9 to be connected with a serial signal terminal of the serial/parallel transform unit 8.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: November 15, 2011
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Kazutaka Shimoosako, Kunio Odaka, Katsuya Aboshi
  • Patent number: 8059962
    Abstract: An apparatus comprising a plurality of data framers, a time division multiplexer coupled to the data framers, and an optical transmitter coupled to the time division multiplexer. Also disclosed is an apparatus comprising an optical receiver, a time division demultiplexer coupled to the optical receiver, and a data framer coupled to the time division demultiplexer. Also disclosed is an apparatus comprising at least one component configured to implement a method comprising combining a first plurality of data frames corresponding to a first plurality of channels into a first plurality of combined data frames using time division multiplexing and transmitting the first combined data frames over a single optical channel.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: November 15, 2011
    Assignee: Futurewei Technologies, Inc.
    Inventor: Frank J. Effenberger
  • Patent number: 8050567
    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 12, 2008
    Date of Patent: November 1, 2011
    Assignee: Applied Micro Circuits Corporation
    Inventors: Glen Miller, Tracy Xiaoming Ma
  • Patent number: 8045858
    Abstract: A method for transmission of multiple, independent data packages across a single optical fiber utilizing both time division multiplexing and wavelength division multiplexing is described. The method includes transmitting a first data package across the single optical fiber at a first wavelength and transmitting a second data package across the same optical fiber at a second wavelength, in either the same direction or in a direction opposite as the first data package, wherein the second data package transmission may be concurrent with the first data package transmission. the method further includes separating the data package transmissions into two optical paths, filtering the second wavelength from a first of the two optical paths, detecting the first data package at the first wavelength, filtering the first wavelength from a second of the two optical paths, and detecting the second data package data at the second wavelength.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: October 25, 2011
    Assignee: The Boeing Company
    Inventor: Tuong Truong
  • 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
  • Publication number: 20110249974
    Abstract: The present invention discloses a method and an apparatus for adjusting a service of optical synchronous digital hierarchy network, and the method comprises: at first configuring the input time-slot space-division cross path to the time-division module after adjustment in space-division module and the time-division cross path of the time-division module after adjustment; and configuring the output time-slot space-division cross path from the time-division module after adjustment in space-division module; deleting the original cross path formed by the time-division module before adjustment.
    Type: Application
    Filed: September 11, 2009
    Publication date: October 13, 2011
    Applicant: ZTE CORPORATION
    Inventors: Xiaoping Tu, Jun Lv
  • Publication number: 20110200335
    Abstract: A system for optical data communication, including: a first sending node including a first data item for transmission to a first receiving node during a first timeslot; a second sending node including a second data item for transmission during a second timeslot; a first optical data link (ODL) and a second ODL; a first output switch configured to switch the first data item from the first sending node onto the first ODL during the first timeslot; a second output switch configured to switch the second data item from the second sending node onto the first ODL during the second timeslot; an optical coupler connecting the first and second ODL; and a first input switch operatively connecting the first receiving node with the second ODL and configured to switch the first data item from the second ODL to the first receiving node during the first timeslot.
    Type: Application
    Filed: February 17, 2010
    Publication date: August 18, 2011
    Applicant: ORACLE INTERNATIONAL CORPORATION
    Inventors: Pranay Koka, Michael Oliver McCracken, Herbert Dewitt Schwetman, Xuezhe Zheng, Ashok Krishnamoorthy
  • Publication number: 20110200332
    Abstract: A system including first and second sending nodes, a horizontal optical data link (ODL) having optical signals propagating in opposite directions in first and second waveguide segments, a vertical ODL having optical signals propagating in the same direction throughout third and fourth waveguide segments, a first optical output switch operatively connecting the first sending node and the first waveguide segment and configured to switch first data item onto the first waveguide segment during a first timeslot, a second optical output switch operatively connecting the second sending node and the second waveguide segment and configured to switch second data item onto the second waveguide segment during a second timeslot, and an optical coupler pair operatively connecting the first and second waveguide segments to the third and fourth waveguide segments, respectively, and redirecting the first and the second data items from the horizontal to the vertical ODL.
    Type: Application
    Filed: March 12, 2010
    Publication date: August 18, 2011
    Applicant: Oracle International Corporation
    Inventors: Michael Oliver McCracken, Pranay Koka, Herbert Dewitt Schwetman, Xuezhe Zheng, Ashok Krishnamoorthy
  • Patent number: 8000606
    Abstract: A method for processing overheads in an optical communication system and a signal processing device are disclosed. The method includes: in a receiving direction, conduct an O/E and S/P conversion for the received optical signal, extract overheads necessary for overheads processing; transmit the overheads in serial; conduct an S/P conversion of the overheads, add fixed reserved overheads, and revert the parallel overheads for overheads processing; in a transmitting direction, generate parallel overheads, extract overheads necessary for overheads processing; transmit the overheads in serial; conduct an S/P conversion of the overheads, revert the overheads, synthesize the overheads with the payload data before the P/S and E/O conversion, and generate and transmit the optical signal. In accordance with the disclosed method and device, a serial bus is employed to transmit overheads, which reduces the number of buses on the motherboard and lowers the complexity of system design.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: August 16, 2011
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Xinhua Xiao, Chengyu Huang
  • Patent number: 8000605
    Abstract: Methods and apparatus for implementing synchronous Optical Time Division Multiplexing are presented. Namely, a method of upconverting and combining N input NRZ optical data signals, each having an approximately equal pulse width and period, into one time-division multiplexed output signal, as well as a method for the inverse, i.e., down converting the N demultiplexed component signals are presented. Apparatus to implement these functionalities is also presented.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: August 16, 2011
    Assignee: Alphion Corporation
    Inventor: Bharat Dave
  • Patent number: 7983561
    Abstract: An optical pulse time spreading device includes S optical pulse time spreading elements that spread input optical pulses into trains of (N×j) chip pulses, where j is an integer greater than zero, S is an integer greater than one, and N is an integer equal to or greater than S. In the chip pulse trains output by the n-th optical pulse time spreading element (n=1, 2, . . . , S), the light in successive chip pulses is shifted in phase by successive integer multiples of the quantity 2?{a+(n?1)/N}, where a is an arbitrary constant (0?a<1). In an optical code-division multiplexing system, this optical pulse time spreading device produces an autocorrelation wave with a high energy and a high signal-to-noise ratio.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: July 19, 2011
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Kensuke Sasaki
  • Patent number: 7974542
    Abstract: An OTDM-DPSK signal generator includes an optical splitter, a first and a second phase modulator, an optical coupler, and a monitor signal splitter. The optical splitter splits an optical pulse string into a first and a second optical pulse string. The first and second phase modulators generate a first and a second channel DPSK signal, respectively. The DPSK signals are provided with one bit delay to generate another DPSK signal, which enters the optical coupler, which outputs an OTDM-DPSK signal, which enters a monitor signal splitter. The monitor signal splitter splits from the OTDM-DPSK signal a monitor signal and inputs the monitor signal to an optical carrier phase difference detector. The detector generates an optical carrier phase difference detection signal as a function of an optical carrier phase difference between optical pulses. The optical carrier phase difference can thus be detected between optical pulses in an OTDM-DPSK signal.
    Type: Grant
    Filed: September 27, 2007
    Date of Patent: July 5, 2011
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Masatoshi Kagawa
  • Publication number: 20110158642
    Abstract: The present invention includes novel techniques, apparatus, and systems for optical WDM communications. Tunable lasers are employed to generate respective subcarrier frequencies which represent subchannels of an ITU channel to which client signals can be mapped. In one embodiment, subchannels are polarization interleaved to reduce crosstalk. In another embodiment, polarization multiplexing is used to increase the spectral density. Client circuits can be divided and combined with one another before being mapped, independent of one another, to individual subchannels within and across ITU channels. A crosspoint switch can be used to control the client to subchannel mapping, thereby enabling subchannel protection switching and hitless wavelength switching.
    Type: Application
    Filed: December 6, 2010
    Publication date: June 30, 2011
    Applicant: VELLO SYSTEMS, INC.
    Inventors: Chris Wilhelm Barnard, Piotr Myslinski, Colin John Wright
  • Publication number: 20110158641
    Abstract: The present invention includes novel techniques, apparatus, and systems for optical WDM communications. Tunable lasers are employed to generate respective subcarrier frequencies which represent subchannels of an ITU channel to which client signals can be mapped. In one embodiment, subchannels are polarization interleaved to reduce crosstalk. In another embodiment, polarization multiplexing is used to increase the spectral density. Client circuits can be divided and combined with one another before being mapped, independent of one another, to individual subchannels within and across ITU channels. A crosspoint switch can be used to control the client to subchannel mapping, thereby enabling subchannel protection switching and hitless wavelength switching.
    Type: Application
    Filed: December 6, 2010
    Publication date: June 30, 2011
    Applicant: VELLO SYSTEMS, INC.
    Inventors: Chris Wilhelm Barnard, Piotr Myslinski
  • Publication number: 20110158651
    Abstract: In the field of photonic integrated communication, a method and an apparatus for filtering locking are provided, so as to solve the problem in the conventional wavelength locking technology that any increase of the wave number also incurs increases in costs and circuit complexity, and it is difficult to extract dithered information. The method and apparatus for filtering locking employ a centralized wavelength locking method of injecting a single dither to a Photonic Integrated Device (PID)/Photonic Integrated Circuit (PIC), thereby reducing circuit board area and control circuit complexity. A weak dither signal can be accurately extracted by means of a combination of analog filtering and digital filtering. The technical solution is appropriate for use in photonic integrated systems in which two or more PID/PIC chips with multi-wavelength modules are cascaded.
    Type: Application
    Filed: March 9, 2011
    Publication date: June 30, 2011
    Applicant: Huawei Technologies Co., Ltd. Huawei Administration Building
    Inventors: Fei Tang, Shuangqi Wu, Hongping Zhang
  • Patent number: 7970241
    Abstract: A modulator includes an electro-optical substrate and a first and second waveguide formed of a doped semiconductor material positioned on a surface of an electro-optical substrate forming a slot therebetween. A doping level of the semiconductor material being chosen to make the first and second waveguide conductive. A dielectric material is positioned in the slot which increases confinement of both an optical field and an electrical field inside the slot. A refractive index of the semiconductor material and a refractive index of the dielectric material positioned in the slot being chosen to reduce the V?·L product of the modulator.
    Type: Grant
    Filed: September 9, 2008
    Date of Patent: June 28, 2011
    Assignee: Photonic Systems, Inc.
    Inventors: Jianxiao Chen, Charles Cox
  • Patent number: 7961798
    Abstract: Wired/wireless optical signal modulation and demodulation apparatuses and methods using an intensity modulation/direct detection method and an orthogonal frequency division multiplexing (OFDM) method are provided. A unipolar OFDM symbol frame is generated by determining the polarity of each of a plurality of sub-frames of a bipolar OFDM symbol frame which comprises both a plurality of positive pulses and a plurality of negative pulses, inverting the polarity of the sub-frames which are determined to be negative, delaying one of the positive sub-frame and a positive sub-frame obtained through the inversion by the duration of the sub-frames, and multiplexing the result of the delaying and whichever of the positive sub-frame and the positive sub-frame obtained through the inversion is not the result of the delaying. The unipolar OFDM symbol frame can guarantee high power amplification efficiency and high transmission power efficiency, and is robust against a multi-path channel environment.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: June 14, 2011
    Assignee: Electronics and Telecommunications Research Institute
    Inventor: Yong Il Jun
  • Patent number: 7957646
    Abstract: The optical time division multiplexer generates a time-division-multiplexed optical signal by time-division-multiplexing optical signals of a plurality of channels, the carrier-wave phases of which are shifted with respect to one another. The circulator guides the multiplexed optical signals split by the optical splitter to the optical interference device and the superimposed light outputted from the optical interference device is guided to the optical intensity detector. The optical interference device extends the pulse width of the multiplexed optical signal to a width equal to or more than the bit interval and superimposes the extended light of an adjacent bit onto the extended light. The optical intensity detector detects the intensity of the superimposed light outputted by the optical interference device. The temperature regulator controls the temperature of the modulator so that the phase difference of the carrier waves constituting the optical signal trains is to be a half wavelength.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: June 7, 2011
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Masatoshi Kagawa
  • Publication number: 20110116799
    Abstract: An apparatus comprising an optical transmitter, a coarse tuner coupled to the optical transmitter and having a first tuning range, a fine tuner coupled to the optical transmitter and having a second tuning range smaller than and within the first tuning range, a wavelength division demultiplexer coupled to the optical transmitter and to a plurality of optical fibers, and a detector coupled to the optical transmitter and the wavelength division demultiplexer. A network component comprising at least one processor configured to implement a method comprising detecting an Optical Time Domain Reflectometry (OTDR) signal spectrum that has a modulated pattern, and detecting a reflected OTDR signal spectrum that has a shifted modulated pattern comprising a frequency shift with respect to the OTDR signal spectrum and a time shift proportional to the frequency shift.
    Type: Application
    Filed: November 13, 2009
    Publication date: May 19, 2011
    Applicant: Futurewei Technologies, Inc.
    Inventor: Frank J. Effenberger
  • Publication number: 20110116803
    Abstract: There is provided a terminal apparatus including a message monitor to gather transmission request information from each of first and second terminating apparatus, a dynamic bandwidth allocation unit to allocate each transmission band in accordance with the gathered transmission request information, determine a size and an alignment position of a time slot in accordance with the allocated transmission band, determine a transmission start time of the time slot, and allocate an extinction period so as to stop a transmission of an optical signal between a time slot of the optical signal with the second transmission rate and a time slot following the time slot of the optical signal with the second transmission rate, and a MAC controller to generate a control frame for notifying each of the first and second terminating apparatus of the transmission start time and the size of the time slot.
    Type: Application
    Filed: November 18, 2010
    Publication date: May 19, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Kyosuke SONE, George ISHIKAWA, Susumu KINOSHITA
  • Patent number: 7945171
    Abstract: A phase control arrangement has a structure in which a Superstructured fiber Bragg Grating (SSFBG) 40 has fifteen unit Fiber Bragg Gratings (FBGs) arranged in series in a waveguide direction. The SSFBG 40 is fixed to the core of an optical fiber 36 that includes a core 34 and cladding 32. The difference ?n between the maximum and minimum of the effective refractive index of the optical fiber is 6.2×10?5. The phase difference of Bragg reflected light from two unit diffraction gratings that adjoin one another from front to back and provide equal code values is given by 2?M+(?/2), where M is an integer. Further, the phase difference of the Bragg reflected light from two unit diffraction gratings that adjoin one another from front to back and provide different code values is given by 2?M+(2N+1)?+(?/2) where M and N are integers.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: May 17, 2011
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Kensuke Sasaki, Akihiko Nishiki
  • Patent number: 7945164
    Abstract: A method, an apparatus, and a system where multiple lower bandwidth optic Ethernet (e.g. 1000Base-FX) signals can be interleaved or encoded onto a single fiber optic link by overclocking the physical layer elements in such a manner as to be transparent to the data link layer and other higher network layers in the Open Systems Interconnection Reference Model (OSI Model) are provided. Such embodiments may provide increased port density over the existing fiber optic gigabit Ethernet (GbE) standards. In embodiments where multiple GbE signals are not channelized, overclocking the physical layer elements may provide increased bandwidth for a single link over existing fiber optic GbE standards.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: May 17, 2011
    Assignee: Cisco Technology, Inc.
    Inventor: James T. Theodoras, II
  • Publication number: 20110097085
    Abstract: An optical transmitter includes: a pre-compensator calculating an electrical field of an optical signal subjected to an electronic pre-compensation with respect to an input digital signal; a parallelizer parallelizing the electrical field of the optical signal calculated by the pre-compensator; a plurality of optical modulators modulating an optical signal based on each of parallelized electrical fields of optical signals; and a time-division multiplexer time-division-multiplexing an optical signal output from the plurality of the optical modulators.
    Type: Application
    Filed: October 25, 2010
    Publication date: April 28, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Shoichiro Oda, Takeshi Hoshida, Takahito Tanimura
  • Publication number: 20110091215
    Abstract: In the field of signal processing technologies, a microwave transmission apparatus, a signal processing method and device in a microwave transmission apparatus are provided, which are capable of improving the signal-to-noise ratio of the service signal and the reliability of the communication signal, and increasing the distance between an indoor unit (IDU) and an outdoor unit (ODU). In the technical solutions, a signal processing method in a microwave transmission apparatus includes: directly multiplexing at least a service signal and a non-service signal, and converting the multiplexed electric signal into a multiplexed optical signal; and sending the multiplexed optical signal to an ODU.
    Type: Application
    Filed: December 27, 2010
    Publication date: April 21, 2011
    Inventors: Xiongbin Huang, Tianxiang Wang, Haiou Gou, Dejun Li
  • Publication number: 20110085794
    Abstract: An apparatus comprising a plurality of optical transmitters coupled to a fiber, a signal generator coupled to the optical transmitters and configured to provide a single pilot tone to the optical transmitters, and a processor positioned within a feedback loop between the fiber and the optical transmitters, the processor configured to adjust a wavelength for each of the optical transmitters to lock the wavelengths. An apparatus comprising at least one processor configured to implement a method comprising receiving an optical signal comprising a pilot tone, detecting an amplitude and a phase of the pilot tone, calculating a quadrature term using the amplitude and the phase, and wavelength locking the optical signal using the quadrature term.
    Type: Application
    Filed: October 14, 2009
    Publication date: April 14, 2011
    Applicant: Futurewei Technologies, Inc.
    Inventors: Hongbing LEI, Xiao A. SHEN, Yu Sheng BAI
  • Patent number: 7920791
    Abstract: Regarding the passive optical network (PON) system of the present invention, in an OLT, data of different bit rates is framed, and framed data rows are subjected to FEC encoding processing without changing the line up of the data, and a check bit is added to the end of the frame, and an optical signal that has been modulated in accordance with the data row to which the check bit has been added is transmitted to the optical transmission line. Then in an ONU that corresponds to a high speed bit rate to which an optical signal from the OLT has been applied via a power splitter, forward error correction of the reception data is performed. As a result in a PON system in which data of different bit rates coexist, the minimum reception rate of a high speed ONU can be improved without having an influence on a low speed ONU.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: April 5, 2011
    Assignee: Fujitsu Limited
    Inventors: Yoshio Sakai, Kazuyuki Mori
  • Publication number: 20110063128
    Abstract: A chamber-status monitoring apparatus includes a plurality of chambers, a time-division multiplexer configured to receive, via optical fiber probes, optical signals from each chamber, to divide each optical signal into first time slots having a predetermined duration, and to multiplex the first time slots to generate an OTDM signal, a multi-input optical emission spectroscope configured to receive and disperse the OTDM signal according to wavelengths to measure spectrum information, and a controller configured to divide the spectrum information of the dispersed OTDM signal into second time slots with a predetermined time interval therebetween, to classify the second time slots according to the chambers to obtain spectrum information of the optical signals of the individual chambers, and to control endpoint detection in each of the chambers in accordance with the spectrum information of the optical signal of the corresponding chamber.
    Type: Application
    Filed: August 18, 2010
    Publication date: March 17, 2011
    Inventors: Sang-Wuk Park, Woo-Seok Kim, Yong-Jin Kim
  • Patent number: 7907843
    Abstract: In a point-to-multipoint network of an optical line terminal (OLT) and multiple optical network units (ONUS) wherein each ONU is enabled to send a signal only within a time period enabled for the ONU, the OLT (or a system installed therein) identifies a defective one of the ONUs. For each of a given series of time periods, the OLT measures an optical reception level of an optical fiber signal in the time period. The OLT stores, in advance, in a table at least the reception level of a received signal from each ONU in association with the ONU. The reception level is measured in a normal state where signals from the ONUs are exclusively received. For each of the given series of time periods, the OLT decides whether a signal from one of the ONUs associated with the time period is exclusively received with no collision with any other signal.
    Type: Grant
    Filed: September 27, 2007
    Date of Patent: March 15, 2011
    Assignee: Fujitsu Limited
    Inventors: Katsuichi Yamaji, Toshimi Kida, Toshihiro Noguchi
  • Patent number: 7885546
    Abstract: A method and apparatus for multiplexing multiple Ethernet-based data streams in an optical network reduce the number of optical transceivers required by the optical network. Multiple data streams are multiplexed into a combined data stream, transmitted from a node in the optical network as the combined data stream, and demultiplexed at the receiving node. Data streams are multiplexed and demultiplexed at the bit level, and packets from each data stream are routed based on a VLAN tag that is contained in the header of each packet. By transmitting the information contained in multiple data streams as a single multiplexed data stream, the number of optical transceivers required for the optical network may be reduced by more than half. An optical supervisory channel may also be bundled with one of the data streams to eliminate the need for a dedicated transceiver for the optical supervisory channel.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: February 8, 2011
    Assignee: Oclaro (North America), Inc.
    Inventors: Samuel Liu, Xiaodong Duan, Giovanni Barbarossa
  • Patent number: 7869713
    Abstract: A method of extracting a predetermined channel from an OTDM signal includes the steps of combining at the inlet of an SOA the OTDM signal and an impulsive signal with impulses temporally synchronized with the channel to be extracted to produce in the SOA FWM, XGM and XPM effects which shift to a length c the channel chosen for extraction with c outside the length d of the OTDM signal with the other channels outlet from the SOA and filtering the SOA outlet to extract components with c d that represent respectively the desired channel and the cleaned OTDM signal. A multiplexer in accordance with the method includes an inlet (14) of an OTDM signal sent to an SOA (24) together with an appropriate impulsive signal. The SOA outlet is filtered by filters (28, 29) to obtain the signal of the extracted channel (16) and the cleaned OTDM signal (15).
    Type: Grant
    Filed: November 28, 2005
    Date of Patent: January 11, 2011
    Assignee: Ericsson AB
    Inventors: Claudio Porzi, Antonella Bogoni, Luca Poti
  • Patent number: 7869710
    Abstract: An optical network unit (ONU) of an Ethernet passive optical network (EPON) and a control method thereof eliminates or substantially reduces instances of an ONU transmitting in time slots other than its allocated time slot. The ONU includes: a medium access controller for accessing a medium without temporal overlapping in order to transmit during one or more allocated TDM time slots without collision in upstream transmission to an optical line terminal; a burst-mode optical transceiver having a separately allocated wavelength before outputting the signal in the upstream transmission; and a complex programmable logic device for controlling an optical output of the burst-mode optical transceiver by monitoring an optical-output control signal from the medium access controller. An erroneous output from an ONU malfunction can be prevented from by cutting off the output once the duration of the allocated time slot has been reached.
    Type: Grant
    Filed: August 15, 2007
    Date of Patent: January 11, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hong-Gi Lee, Ho-Jun Keum, Jae-Hwang Ryu, Soon-Ho Jang
  • Publication number: 20100322634
    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: Application
    Filed: February 17, 2009
    Publication date: December 23, 2010
    Inventors: Daisuke Murayama, Noriyuki Oota, Noriki Miki
  • Publication number: 20100316387
    Abstract: In a passive optical network, power consumption of the ONU can be reduced by communicating a transmission schedule from the OLT to the ONU that indicates time slots in which the ONU is scheduled to receive payload transmissions from the OLT. Components of the ONU that would normally operate continuously, including processing payloads addressed to other ONUs, are placed in a reduced power state outside of the ONU's allocated time slots.
    Type: Application
    Filed: June 10, 2009
    Publication date: December 16, 2010
    Applicant: Alcatel-Lucent USA Inc.
    Inventor: Dusan Suvakovic
  • Publication number: 20100303464
    Abstract: A method, a system, and a device for transmitting data in an OTN are disclosed herein. The method for transmitting data in an OTN includes: mapping the at least one pair of ODU0's to an ODTU to form an ODTUvkt, wherein k is greater than or equal to 1, t is 2 or 3, and an external structure of the ODTUvkt is the same as an external structure of an ODTUkt; and mapping the ODTUvkt to timeslot i and timeslot i+n of a 1.25 G ODUt, indicating the type of at least one pair of ODU0's carried in timeslot i to be ODUk, and transmitting the ODUk to a destination node.
    Type: Application
    Filed: August 10, 2010
    Publication date: December 2, 2010
    Applicant: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Limin DONG, Chiwu Ding, Qiuyou Wu, Xin Xiao
  • Patent number: 7844180
    Abstract: The invention relates to a device and a method for converting WDM signals into an OTDM signal. The device comprises shifting means (102, 103, 104) adapted to introduce a time shift between the pulses of the WDM signals carried by the optical carriers, modulation means (112, 113, 114) adapted to modify the optical power of the WDM signals, an optical temporal multiplexer/demultiplexer (120), a birefringent propagation medium (130) into which the WDM signals are injected in such a manner as to achieve a soliton trapping phenomenon, and absorption means (140) adapted to introduce optical losses into the components of the OTDM signal. This device performs WDM/OTDM conversion at very high bit rates. It also performs OTDM/WDM conversion. It is intended to be installed in long-haul telecommunication networks.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: November 30, 2010
    Inventor: Erwan Pincemin
  • Patent number: 7844181
    Abstract: A method for negotiating speed between a Fiber Channel (FC) local client and a remote FC client across a DWDM network is provided. A transmission speed of the local FC client at a local ingress transport interface is detected. The data from the local FC client is forwarded along with the detected transmission speed to a remote egress transport interface. The remote egress interface forwards the data at the detected transmission speed to the remote FC client. The present invention eliminates complex speed negotiation state machines that would otherwise be required to make the DWDM transport behave like a virtual wire with respect to the FC ports and to allow the FC clients to negotiate the desired speed directly between themselves.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: November 30, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: Sriram Natarajan, Jayakrishna M. Menon, Gary K. Chan
  • Publication number: 20100296813
    Abstract: A method and apparatus are provided for processing a composite optical signal formed of a sequence of time sectors obtained by time-division multiplexing a plurality of optical signals transmitted on a plurality of transmission channels of a shared optical access network. The method includes: taking account of a schedule for transmission of the plurality of optical signals in the access network, the schedule associating with a time sector an optical signal of the sequence and a transmission channel of the plurality of transmission channels used by the optical signal; recovering a set of representative performance parameters of the transmission channel associated with the time sector; and adaptively correcting the time sector using the set of parameters.
    Type: Application
    Filed: December 14, 2007
    Publication date: November 25, 2010
    Applicant: FRANCE TELECOM
    Inventors: Philippe Chanclou, Julien Poirrier, Franck Payoux
  • Patent number: 7831145
    Abstract: The present disclosure provides a passive optical network (PON) system and a method for protecting the service of the system for service recovery and fault locating in case of a failure of the network, wherein the PON system comprises an optical line terminal (OLT), an optical distribution network (ODN) and an optical network terminal (ONT) equipment protection group comprising a plurality of ONT equipment groups, each of which is connected to at least one of other ONT equipment groups within the ONT equipment protection group for the mutual protection relationship. The PON system of the present disclosure does not require equipment and link redundancy for backup, contributes to reduced cost and improved utilization of resources, and provides a means for diagnosing any faults of the links and equipment in the network.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: November 9, 2010
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Hai Gao, Gang Zheng
  • Patent number: 7831147
    Abstract: This invention provides a new architecture for a communication system between head-ends and end-users which expands bandwidth and reliability of the communication system. A mux-node receives communication signals from a head-end and forwards the received communication signals to one or more mini-fiber nodes. The connection to the head-end is via a small number of optical fibers and the connections to each of the mini-fiber nodes may be via one or more optical fibers that may provide full duplex communication. The head-end may communicate with the mux-node using digital or digital and analog signals. The mini-fiber nodes may combine the signals received from the head-end with loop-back signals used for local media access control prior to forwarding the signals to the end-users. Upstream data are received by the mini-fiber nodes and transmitted to the mux-node.
    Type: Grant
    Filed: November 10, 2008
    Date of Patent: November 9, 2010
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Charles D. Combs, Thomas Edward Darcie, Bhavesh N. Desai, Alan H. Gnauck, Xiaolin Lu, Esteban Sandino, Oleh J. Sniezko, Anthony G. Werner, Sheryl Leigh Woodward
  • 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
  • Publication number: 20100254708
    Abstract: A method includes transmitting a plurality of time-division-multiplexed return channels from a plurality of optical network terminal outputs to a plurality of cable modem termination system inputs. Transmitting the plurality of time-division-multiplexed return channels includes transmitting a plurality of frequency-division-multiplexed return signals from the plurality of optical network terminal outputs to the plurality of cable modem termination system inputs. An apparatus includes a plurality of optical network terminals; an optical receiver coupled to the plurality of optical network terminals; an optical splitter coupled to the optical receiver; a plurality of cable modem termination system inputs. A plurality of time-division-multiplexed return channels are transmitted from the plurality of optical network terminals to the plurality of cable modem termination systems and the plurality of time-division-multiplexed return channels include a plurality of frequency-division-multiplexed return signals.
    Type: Application
    Filed: March 4, 2010
    Publication date: October 7, 2010
    Inventors: Krzysztof Pradzynski, Oleh Sniezko