Subcarrier Multiplexing Patents (Class 398/76)
  • Patent number: 10419153
    Abstract: An optical transmitter includes: a light source; a wavelength detecting unit configured to detect a wavelength of light emitted from the light source; a wavelength difference information generating unit configured to generate wavelength difference information representing a wavelength difference between a predetermined reference wavelength and a wavelength of the light detected by the wavelength detecting unit; a subcarrier count determination unit configured to determine a number of subcarriers to be used, based on the wavelength difference indicated by the wavelength difference information; a multi-valued level determination unit configured to determine, for each of the subcarriers, a multi-valued level which is a number of bits transmitted by a corresponding subcarrier of the subcarriers; a modulated signal generating unit configured to generate a modulated signal by modulating the subcarriers such that each of the subcarriers has the determined multi-valued level.
    Type: Grant
    Filed: September 24, 2018
    Date of Patent: September 17, 2019
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Kiyotoshi Noheji, Masato Nishihara
  • Patent number: 10261014
    Abstract: Metrology systems and methods are provided herein, which comprise an optical element that is positioned between an objective lens of the system and a target. The optical element is arranged to enhance evanescent modes of radiation reflected by the target. Various configurations are disclosed: the optical element may comprise a solid immersion lens, a combination of Moiré-elements and solid immersion optics, dielectric-metal-dielectric stacks of different designs, and resonating elements to amplify the evanescent modes of illuminating radiation. The metrology systems and methods are configurable to various metrology types, including imaging and scatterometry methods.
    Type: Grant
    Filed: December 26, 2014
    Date of Patent: April 16, 2019
    Assignee: KLA-Tencor Corporation
    Inventors: Noam Sapiens, Joel Seligson, Vladimir Levinski, Daniel Kandel, Yoel Feler, Barak Bringoltz, Amnon Manassen, Eliav Benisty
  • Patent number: 9872416
    Abstract: The present invention discloses a communications product (100), including a remote radio module (10) and a mounting kit (30), where the mounting kit (30) includes a fastening part (32), the fastening part (32) is configured to mount and fasten the remote radio module (10) to a holder, the mounting kit (30) further includes a ventilation part (34) and an air supply part (36), an air source is disposed inside the air supply part (36), the ventilation part (34) is connected between the fastening part (32) and the air supply part (36), a ventilation channel is disposed inside the ventilation part (34), and the ventilation channel allows the air supply part (36) to communicate with the remote radio module (10), so that an air flow generated by the air source reaches the remote radio module (10) after passing through the ventilation channel, to dissipate heat for the remote radio module.
    Type: Grant
    Filed: February 17, 2017
    Date of Patent: January 16, 2018
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Youhe Ke, Yuping Hong, Mingliang Hao
  • Patent number: 9866347
    Abstract: A band control system, a band control apparatus and a communication apparatus which realize low-latency band allocation assuming a plurality of radio control units are proposed. The band control system according to the present invention is a band allocation control system for optical communication which performs connection between a plurality of radio transmitting/receiving units connected to radio terminals and a plurality of radio control units corresponding to the plurality of radio transmitting/receiving units. Each of the radio control units includes a radio communication timing calculating unit configured to calculate a radio communication timing of each of the radio terminals in a connection network.
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: January 9, 2018
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Masahiro Sarashina
  • Patent number: 9857661
    Abstract: A photonic microwave generation apparatus and a method thereof are disclosed. A comb-like optical signal generation module of the photonic microwave generation apparatus generates a comb-like optical signal. The comb-like optical signal is injected into a photonic microwave generation module of the photonic microwave generation apparatus, wherein the photonic microwave generation module includes a microwave generation laser. An optical power and a carrier frequency of the comb-like optical signal are adjusted so as to place the microwave generation laser in period-one nonlinear dynamics, and, at the same time, to phase-lock an oscillation sideband of the period-one nonlinear dynamics by one harmonic of the comb-like optical signal. Under such operation, the microwave generation laser emits an output optical signal that carries a microwave signal of a narrow linewidth and a stable frequency, which can be retrieved from the output optical signal by using a photodetector.
    Type: Grant
    Filed: February 29, 2016
    Date of Patent: January 2, 2018
    Assignee: National Cheng Kung University
    Inventors: Sheng-Kwang Hwang, Yu-Han Hung
  • Patent number: 9596527
    Abstract: A conversion module including physical layer and control modules. The physical layer module, via an optical network, receives first data from a service provider. The control module, via a coaxial cable network: transmits the first data, via sub-carriers, from the conversion module to a first network module according to a first bit loading profile; requests from the first or second network module a report that indicates channel conditions respectively for the sub-carriers; based on the request, receives the report; updates a second bit loading profile based on the report; transmits, to the first or second network module, the updated second bit loading profile or a difference between the first and updated second bit loading profiles; and subsequent to performing a switch over between the first and second bit loading profiles, transmit second data according to the updated second bit loading profile to the first or second network module.
    Type: Grant
    Filed: November 5, 2014
    Date of Patent: March 14, 2017
    Assignee: Marvell World Trade Ltd.
    Inventors: Jin Zhang, Kok-Wui Cheong
  • Patent number: 9419719
    Abstract: An apparatus comprises a digital signal processing module configured to receive a data stream and generate a plurality of digital multiple tones, a plurality of digital-to-analog converters coupled to the digital signal processing module, a plurality of drivers coupled to respective digital-to-analog converters, an electro-optic modulator having inputs coupled to the drivers and outputs coupled to a fiber and a multi-wavelength light source coupled to the electro-optic modulator.
    Type: Grant
    Filed: March 19, 2014
    Date of Patent: August 16, 2016
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Zhiping Jiang, Chen Chen, Zhuhong Zhang, Chuandong Li
  • Patent number: 9271058
    Abstract: A communications network wherein first and second optical signals can be launched into an optical fiber in respective first and second regions of a transmission window such that controllable filters can be used to selectively recover the first and second optical signals. This partitioning of the transmission window allows two incompatible optical signals to coexist in the same optical fiber.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: February 23, 2016
    Assignee: BRITISH TELECOMMUNICATIONS PUBLIC LIMITED COMPANY
    Inventor: Andrew Lord
  • Patent number: 9240857
    Abstract: According to one embodiment of the invention, fiber optic communications method is described. The method comprises a first operation of dynamically identifying frequencies at which spectral nulls occur in a signal received via an optical fiber, and thereafter, segregating communications over the optical fiber into a set of inter-null bands defined by the spectral nulls.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: January 19, 2016
    Assignee: Menara Networks
    Inventor: Salam Elahmadi
  • Patent number: 9182649
    Abstract: In an optical network system: control light is generated by optical modulation based on a modulated data signal which is generated by modulation of a carrier signal with a data signal; and the control light is optically combined with an optical carrier which is to propagate through a nonlinear optical medium, so as to cause cross phase modulation of the optical carrier with the control light in the nonlinear optical medium.
    Type: Grant
    Filed: March 16, 2011
    Date of Patent: November 10, 2015
    Assignee: FUJITSU LIMITED
    Inventor: Shigeki Watanabe
  • Patent number: 9154530
    Abstract: The present invention provides a facility management platform to monitor and view the status of a plurality of individually addressable downstream devices including, but not limited to, addressable terminals, IRG's, settops, cable modems, taps, nodes, and/or hubs at a network control center. The FMP may display problems at these downstream devices, for example, power loss, and/or may automatically notify the appropriate companies and/or personnel to correct the problem.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: October 6, 2015
    Assignee: AT&T INTELLECTUAL PROPERTY II, L.P.
    Inventors: Irwin Gerszberg, Jeffrey S. Martin, Thomas Oplinger, Philip A. Treventi, Hopeton S. Walker
  • Patent number: 9148247
    Abstract: An optical transport system configured to transmit information using two or more modulated optical carriers spaced at spectral intervals that are smaller than the baud rate. An example optical receiver in the optical transport system includes a signal equalizer configured to implement frequency-diversity multiple-input/multiple-output signal processing directed at canceling the effects of inter-carrier interference caused by the spectral overlap between adjacent modulated optical carriers to enable the optical receiver to recover individual data streams encoded onto the different modulated optical carriers at the corresponding optical transmitter(s). Some embodiments of the optical transport system may advantageously be capable of achieving a higher spectral efficiency than the spectral efficiency supported by the optical orthogonal-frequency-division-multiplexing transmission format.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: September 29, 2015
    Assignee: Alcatel Lucent
    Inventor: Noriaki Kaneda
  • Patent number: 9106359
    Abstract: In an optical network system a carrier light propagates along a transmission line. A control light generator included in an optical multiplexing apparatus generates a control light obtained by modulating an intensity-modulated light by a data signal. A multiplexer combines the control light with the carrier light for modulating the carrier light in a nonlinear optical medium in the transmission line by the control light. The carrier light which propagates along the transmission line is modulated in the nonlinear optical medium on the basis of the control light.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: August 11, 2015
    Assignee: FUJITSU LIMITED
    Inventors: Tomoyuki Kato, Shigeki Watanabe
  • Patent number: 9094271
    Abstract: The disclosure discloses a method for reducing mutual interference of multi-carrier, comprising: adjusting the delay of at least one modulation signal; respectively modulating each adjusted modulation signal onto each modulated signal; and comparing the performance indices of modulated signals with set performance indices, wherein the delay of at least one modulation signal is adjusted when the set performance indices are not reached, until the performance indices of modulated signals reach the set performance indices, and each current modulated signal is set as an output signal, or each current modulation signal is set as an input signal when the set performance indices are reached. The disclosure further discloses an apparatus for reducing mutual interface of multi-carrier.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: July 28, 2015
    Assignee: ZTE CORPORATION
    Inventors: Fanlong Li, Wenzhong Bi, Jinming Lao
  • Publication number: 20150131999
    Abstract: A method performed by a transceiver for use in fibre network for sending and/or receiving signals. Transceiver includes SCM device; laser diode; Red-Blue Filter, RBF, having red, blue and common channels; PD; and Subcarrier Demultiplexing, SCDM, device. SCM device receives electromagnetic signals on at least two input ports, multiplexes electromagnetic signals and outputs signal to laser diode. Laser diode receives signal, converts signal to optical signals comprising plurality of subcarriers of different frequencies distributed in frequency around main optical carrier, and outputs subcarriers to red channel of RBF. RBF receives subcarriers and outputs to the fibre network via common channel. RBF receives subcarriers on common channel and filters out blue frequencies and outputs to photo diode. Photodiode receives the subcarriers having blue wavelengths, converts subcarriers into electromagnetic signal and outputs electromagnetic signal to SCDM device.
    Type: Application
    Filed: June 4, 2013
    Publication date: May 14, 2015
    Applicant: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Patryk Urban, Boris Dortschy, Gemma Vall-Llosera
  • Publication number: 20150125152
    Abstract: A multi direction variable transceiver including a transmitter comprising a subcarrier aggregator including at least one variable transmitter splitter and at least one variable transmitter coupler. The transceiver typically includes a receiver having at least one variable receiver splitter and at least one variable receiver coupler. In some examples, each of the transmitter and the receiver may include a controller for dynamically adjusting a splitting ratio for at least one of the variable receiver splitter, variable receiver coupler, variable transmission splitter and variable transmission coupler.
    Type: Application
    Filed: November 6, 2014
    Publication date: May 7, 2015
    Inventors: Philip Ji, Ting Wang
  • Patent number: 9002204
    Abstract: A Wavelength Division Multiplexed Orthogonal Frequency Division Multiple Access Passive Optical Network (WDM-OFDMA-PON) includes a passive last-mile optical split terminated by optical network units (ONUs) with OFDMA transceivers; a standard single mode fiber (SSMF) link; a central office optical line terminal (CO-OLT) coupled to SSMF link and the passive last-mile optical split, wherein the CO-OLT comprises an OFDMA transceiver, burst-mode-free operation, inline optical dispersion compensation free operation, and WDM-enabled operation.
    Type: Grant
    Filed: October 10, 2011
    Date of Patent: April 7, 2015
    Assignee: NEC Laboratories America, Inc.
    Inventors: Neda Cvijetic, Milorad Cvijetic, Ting Wang
  • Patent number: 9002205
    Abstract: System for connecting a plurality of digital subscribers to a data network, comprising a local part connected, by an optical fiber link, to a remote part. Said local part comprises a plurality of DSLAM line cards with xDSL over fiber transceiver that, in turn, comprise a plurality of xDSL lines comprising a modified analog front end which comprises an digital-analog converter to transform a transmitted digital downstream signal into an analog downstream signal; an oscillator which fixes an oscillation frequency for the xDSL line; a mixer, directly connected to the output to convert the analog downstream signal into the oscillation frequency; and a band pass filter centered at the oscillation frequency which filters the converted analog downstream signal.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: April 7, 2015
    Assignee: Telefonica, S.A.
    Inventors: Manuel Sanchez Yangüela, Pablo Alberto Yagüe Valentin
  • Patent number: 8995843
    Abstract: Disclosed is an optical signal transmitting apparatus including: an optical carrier generator configured to generate a plurality of optical carriers and outputs the optical carriers to optical modulators corresponding to the optical carriers, respectively; a plurality of optical modulators configured to modulate the optical carriers, respectively, according to an input signal; and an optical combiner configured to couple a plurality of optical signals from the plurality of optical modulators.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: March 31, 2015
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Hwan Seok Chung, Sun Hyok Chang
  • Publication number: 20150086204
    Abstract: An optical transport system configured to transmit information using two or more modulated optical carriers spaced at spectral intervals that are smaller than the baud rate. An example optical receiver in the optical transport system includes a signal equalizer configured to implement frequency-diversity multiple-input/multiple-output signal processing directed at canceling the effects of inter-carrier interference caused by the spectral overlap between adjacent modulated optical carriers to enable the optical receiver to recover individual data streams encoded onto the different modulated optical carriers at the corresponding optical transmitter(s). Some embodiments of the optical transport system may advantageously be capable of achieving a higher spectral efficiency than the spectral efficiency supported by the optical orthogonal-frequency-division-multiplexing transmission format.
    Type: Application
    Filed: September 20, 2013
    Publication date: March 26, 2015
    Applicant: ALCATEL-LUCENT USA INC.
    Inventor: Noriaki Kaneda
  • Patent number: 8989581
    Abstract: An optical network for reassigning a carrier wavelength of an optical signal may include first and second optical nodes. The first optical node may be configured to transmit an optical signal along an optical path. The first optical node may also be configured to tune a carrier wavelength of the optical signal from a first wavelength to a second wavelength, according to a continuous function, to reassign the carrier wavelength of the optical signal. The second optical node may be configured to receive the optical signal and may include a feedback loop configured to adjust a wavelength of a reference optical signal to approximate the carrier wavelength of the optical signal.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: March 24, 2015
    Assignee: Fujitsu Limited
    Inventors: Inwoong Kim, Paparao Palacharla, Xi Wang, Motoyoshi Sekiya
  • Patent number: 8983296
    Abstract: An optical modulator combines and inputs a signal light propagating through the optical network and a control light having information concerning the optical network to a nonlinear optical medium. The optical modulator modulates the signal light according to changes in intensity of the control light, in the nonlinear optical medium.
    Type: Grant
    Filed: March 27, 2012
    Date of Patent: March 17, 2015
    Assignee: Fujitsu Limited
    Inventor: Shigeki Watanabe
  • Patent number: 8965207
    Abstract: A device for inserting/extracting at least one optical subband into an optical channel consisting of a plurality of optical subbands. The device includes an extraction means that is capable of extracting a first optical subband belonging to the optical channel, a suppression means that is arranged so as to obtain a filtered optical channel from the optical channel wherein at least one second subband is suppressed, and a coupling means that is capable of inserting a replacement optical subband in place of the second subband in the filtered optical channel so as to obtain a modified optical channel. The device moreover relates to an optical insertion/extraction switcher, using one or more insertion/extraction devices, and to the corresponding insertion/extraction methods.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: February 24, 2015
    Assignee: Orange
    Inventor: Erwan Pincemin
  • Patent number: 8958697
    Abstract: A system and method for managing the optical layer network data communications of an optical fiber data network by an optical transceiver module is disclosed. The management of the optical layer network data communications comprising data link layer functions or layer 2 functions in an OSI model. Benefits include reduction in reduced cost of network deployments from consolidation of network equipment, such as switches, and reduction in power consumed as well as enabling point-to-multipoint network connections from previously only point-to-point network connection.
    Type: Grant
    Filed: July 8, 2012
    Date of Patent: February 17, 2015
    Inventors: Alexander I. Soto, Walter G. Soto
  • Patent number: 8934773
    Abstract: A method for data processing in an optical network includes providing several main wavelengths and processing a subcarrier modulation for the several main wavelengths. An optical network component and a communication system including such an optical network component are also provided.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: January 13, 2015
    Assignee: Xieon Networks S.a.r.l.
    Inventors: Erich Gottwald, Karl Kloppe, Harald Rohde
  • Patent number: 8909046
    Abstract: A system for transporting a plurality of analog and/or digital signals over an optical fiber can include one or more master modems for modulating digital signals and/or RF inserters modulating video signals. The RF signals from the modem(s)/RF inserters are up-converted resulting in frequency bands that are non-overlapping and are spaced apart within a single sub-octave. The sub-octave signal is then converted into an optical signal and directed onto an end of an optical fiber. At the downstream end of the optical fiber, the received optical signal is converted to an RF signal at an optical receiver. The RF signal is then filtered, down-converted and directed to a selected coaxial distribution unit. From the coaxial distribution unit, the RF signal is demodulated, e.g. at a slave modem, to recover the initial analog and/or digital signal.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: December 9, 2014
    Assignee: Titan Photonics
    Inventors: Chen-Kuo Sun, Peter H. Wolff
  • Patent number: 8903238
    Abstract: A system, e.g. for optical communication, includes an I-Q modulator and a transmission signal processor. The I-Q modulator is configured to modulate a first light source in response to first I and Q modulation signals. The transmission signal processor is configured to receive a data stream including data corresponding to a first data subchannel. The processor maps the data subchannel to an optical transmission subchannel and outputs the first I and Q modulation signals. The I and Q modulation signals modulate the light source to produce an optical transmission signal that includes wavelength components corresponding to the optical transmission subchannel.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: December 2, 2014
    Assignee: Alcatel Lucent
    Inventors: Timo J. Pfau, Noriaki Kaneda, Young-Kai Chen
  • Patent number: 8897648
    Abstract: Systems and methods are provided for network communication using wireless base stations and an optical orthogonal frequency division multiple access (OFDMA) signal generated on an optical wavelength, with the optical OFDMA signal being composed of a plurality of OFDMA subcarriers. A multi-level modulator modulates each of the plurality of OFDMA subcarriers. A single optical wavelength propagates each of the plurality of OFDMA subcarriers to different base stations; a passive optical splitter delivers the optical OFDMA signal to different base stations; and an OFDMA subcarrier de-multiplexer delivers and extracts traffic for each of the base stations in an electronic-domain, wherein the extracted traffic is remodulated in a wireless signal format. Antennas at each of the base stations transmit wireless signals, and the wireless signals are recovered and processed from the base stations.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: November 25, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Neda Cvijetic, Milorad Cvijetic, Ting Wang
  • Patent number: 8897645
    Abstract: A system and method for improving receiver sensitivity of an DD-OFDM system without using frequency guard band. The method having: interleaving input data to the DD-OFDM system to generate interleaved data; encoding the input data with a first recursive systematic convolutional code to generate a first recursive systematic convolutional encoded data; encoding the interleaved data with a second recursive systematic convolutional code to generate a second recursive systematic convolutional encoded data; puncturing the first recursive systematic convolutional encoded data and the second recursive systematic convolutional encoded data to generate a parity sequence; and combining the input data with the parity sequence to generate coded DD-OFDM data; wherein the parity sequence is generated by using different puncturing rates for different OFDM subcarriers, so as to obtain higher spectral efficiency.
    Type: Grant
    Filed: December 1, 2010
    Date of Patent: November 25, 2014
    Assignee: ZTE (USA) Inc.
    Inventor: Jianjun Yu
  • Patent number: 8891964
    Abstract: An optical network includes a multidimensional coder and modulator for handling multiple-in-multiple-out MIMO spatial lightpath properties and content of any specific supercarrier, a spatial mode multiplexer responsive to orthogonal frequency division multiplexing OFDM transmissions and the multidimensional coder, a spatial-spectral routing node coupled over a fiber link to the spatial mode multiplexer for performing switching granularity by a spatial mode reconnection, a multidimensional decoder and demodulator; and a spatial mode demultiplexer coupled over a fiber link to the spatial-spectral routing node and responsive to the multidimensional decoder and demodulator.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: November 18, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Milorad Cvijetic, Ivan B. Djordjevic, Neda Cvijetic, Ting Wang
  • Patent number: 8873952
    Abstract: The present invention is directed to a method including determining an appropriate power level for a phase modulator for an optimum number of subcarriers; and applying the determined appropriate power level via a controller to produce the optimum number of subcarriers, wherein the optimum number of subcarriers enables an optical-orthogonal frequency division multiplex O-OFDM based variable rate transmitter with automatic control by a controller to produce an optimum setting based on a required rate.
    Type: Grant
    Filed: August 17, 2012
    Date of Patent: October 28, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Philip Nan Ji, Yue-Kai Huang, Ting Wang
  • Publication number: 20140314410
    Abstract: A transmitter for an optical telecommunication system on a weakly multimode fiber is disclosed. One aspect is a transmitter including an encoder transforming each block of symbols to be transmitted into a code matrix, each element of the matrix being relative to a time of use and to a propagation mode of the weakly multimode fiber. The transmitter can include a plurality of modulators respectively associated with the different propagation modes, each modulator modulating a laser beam during a time of use. Each modulator can modulate a laser beam by use of an element of the corresponding matrix, the elements of the matrix of the code being subjected beforehand to an OFDM modulation upstream of said modulators. Each of the modulated beams can be input into the weakly multimode fiber to propagate therein according to a separate mode.
    Type: Application
    Filed: June 22, 2012
    Publication date: October 23, 2014
    Applicant: INSTITUT MINES-TELECOM
    Inventors: Sami Mumtaz, Ghaya Rekaya-Ben Othman, Yves Jaouen
  • Publication number: 20140314415
    Abstract: A method and system for reducing crosstalk among subcarriers of a super-channel may apply a frequency shift to selected intermediate subcarrier bands upon optical modulation. The frequency shift may be applied to equally spaced optical frequencies between a first optical frequency and a last optical frequency respectively corresponding to two end subcarrier bands that define a fixed bandwidth of the super-channel. The frequency shift may result in the intermediate subcarrier bands being optically modulated at variably spaced optical frequencies within the fixed bandwidth of the super-channel.
    Type: Application
    Filed: September 19, 2013
    Publication date: October 23, 2014
    Applicant: Fujitsu Limited
    Inventors: Olga Vassilieva, Motoyoshi Sekiya, Takeshi Hoshida
  • Publication number: 20140314416
    Abstract: A method and system for reducing crosstalk among subcarriers of a super-channel may involve adjusting power levels of the subcarriers. In one example, power levels of edge and/or intermediate subcarriers may be reduced relative to center subcarriers in the super-channel band. The adjustment in power level may lead to overall reduction in optical signal-to-noise ratio degradation.
    Type: Application
    Filed: September 20, 2013
    Publication date: October 23, 2014
    Applicant: Fujitsu Limited
    Inventors: Olga Vassilieva, Motoyoshi Sekiya
  • Publication number: 20140301734
    Abstract: An optical receiver comprises an optical port configured to receive an encoded optical signal, and a demodulation block indirectly coupled to the port and comprising a multiplexer, wherein the multiplexer is configured to receive an encoded electrical signal, wherein the encoded electrical signal is associated with the encoded optical signal, and wherein the encoded electrical signal is encoded using a code division multiple access (CDMA) scheme, receive a code associated with the scheme, perform a dot multiplication of the encoded electrical signal and the code, and generate a differential voltage based on the dot multiplication.
    Type: Application
    Filed: December 10, 2013
    Publication date: October 9, 2014
    Applicant: Futurewei Technologies, Inc.
    Inventor: Liming Fang
  • Publication number: 20140294393
    Abstract: A method for transmitting digital information having a predetermined bit-rate (B) via a nonlinear optical channel includes determining a combination of transmission parameters comprising a number (N) of subcarriers, an information symbol rate (S) for each subcarrier, and a number (b) of bits per symbol on each subcarrier, such that B=NSb. An optical signal is generated comprising the plurality (N) of orthogonal optical subcarriers. Each subcarrier is modulated to carry a proportion (Sb/B) of the total bit-rate (B) of the digital information. The optical signal is then transmitted to a corresponding optical receiver via the nonlinear optical channel. The received signal has a measurable signal quality (Q) which is a function of the transmission parameters (N, S, b).
    Type: Application
    Filed: March 2, 2012
    Publication date: October 2, 2014
    Applicant: Ofidium Pty Ltd.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Publication number: 20140270777
    Abstract: An electronic device comprising an optical gate, an electrical input an electrical output and a wide bandgap material positioned between the electrical input and the electrical output to control an amount of current flowing between the electrical input and the electrical output in response to a stimulus received at the optical gate can be used in wideband telecommunication applications in transmission of multi-channel signals.
    Type: Application
    Filed: March 18, 2014
    Publication date: September 18, 2014
    Applicant: Lawrence Livermore National Security, LLC
    Inventor: Stephen Sampayan
  • Patent number: 8831441
    Abstract: To reduce PAPR in an optical OFDM communication system, light is phase-modulated by a base-band OFDM signal which is the output of a transmission signal processing unit 100 provided in an inner section of an optical receiver. When optical communication is implemented with the light as signal light, PAPR of low level of almost 0 dB can be achieved at places in an inner section of an optical fiber wherein the optical power is large. The signal light is propagated along an optical fiber which is a transmission path, the light is passed through a delay interferometer, and converted to electrical signals by two optical receivers. Each of the two electrical signals is converted to a subcarrier by FFT signal processing and an AD converter disposed in an inner section of the optical receivers, then, subcarriers having the same frequency are subtracted and decoded, and data is regenerated.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: September 9, 2014
    Assignee: Hitachi, Ltd.
    Inventor: Shinya Sasaki
  • Publication number: 20140248055
    Abstract: A method and apparatus for short range multi-device communications in personal area networks (PANs) using Terahertz bands.
    Type: Application
    Filed: May 16, 2014
    Publication date: September 4, 2014
    Applicant: InterDigital Patent Holdings, Inc.
    Inventors: Martino Freda, Jean-Louis Gauvreau, Joseph Murray
  • Publication number: 20140241727
    Abstract: The invention relates to a system and method of communication between optical transceivers in an optical WDM network, wherein a broad-band modulation of optical signals in a primary frequency band is utilized for transmitting primary high-speed data, while a plurality of relatively low-frequency in-band subcarriers is used to modulate the optical signals to transmit secondary data between network nodes, wherein the plurality of low-frequency subcarriers lie at least in part within the primary frequency band.
    Type: Application
    Filed: February 27, 2013
    Publication date: August 28, 2014
    Inventors: Hock Gin LIM, Thomas Beck Mason, Michael Shinsky, Victor Steinberg
  • Patent number: 8798471
    Abstract: A method for processing data in an optical network element. A multi-carrier signal is linear pre-coded and the linear pre-coded signal is modulated. A corresponding optical network element is also described.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: August 5, 2014
    Assignee: Xieon Networks S.a.r.l.
    Inventors: Oscar Gaete, Leonardo Coelho, Bernhard Spinnler, Norbert Hanik, Ernst-Dieter Schmidt
  • Publication number: 20140212140
    Abstract: We describe and demonstrate a novel and simple scheme to generate flattened optical subcarriers using only phase modulators driven by single frequency fundamental sinusoidal sources. 160.8 Gb/s PM-QPSK experiment over a single subcarrier has been demonstrated.
    Type: Application
    Filed: October 16, 2013
    Publication date: July 31, 2014
    Applicants: ZTE (USA) INC., ZTE Corporation
    Inventor: Jianjun Yu
  • Publication number: 20140199073
    Abstract: Techniques for optical communications using optical orthogonal frequency division multiplexing (OFDM) include operating a signal transmitter to modulate laser light to produce modulated light that carries, in optical domain, OFDM subcarriers for carrying communication information, without a frequency guard band between the OFDM subcarriers, and pilot subcarriers for channel estimation at a signal receiver, each pilot subcarrier being free of communication information, and controlling optical power of the pilot subcarriers to vary with optical frequencies of the pilot subcarriers so that optical power of a pilot subcarrier at a high optical frequency is different from optical power of another pilot subcarrier at a low optical frequency.
    Type: Application
    Filed: August 10, 2012
    Publication date: July 17, 2014
    Applicant: ZTE (USA) INC.
    Inventor: Jianjun Yu
  • Patent number: 8781325
    Abstract: A method of generating a multi-subcarrier optical signal is disclosed. A local oscillator oscillates one or more data signals to generate one or more oscillating data signals. A series of modulators phase modulate a lightwave to generate a phase modulated lightwave, wherein the series of modulators are driven by the one or more oscillating data signals. The intensity modulator modulates the phase modulated lightwave, the intensity modulator being driven by one of the oscillating data signals, to generate the multi-subcarrier optical signal.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: July 15, 2014
    Assignees: ZTE Corporation, ZTE (USA) Inc.
    Inventor: Jianjun Yu
  • Patent number: 8781326
    Abstract: An energy efficient OFDM transceiver includes a transmitter using a decision processor to control first internal elements that can be operated in parallel and can be selectively powered off or hibernated, and a receiver using a processing decision element to control second internal elements that can be operated in parallel and can be selectively powered off or hibernated, wherein control of the first and second internal elements enables tracking status of network traffic, adjustment of OFDM bandwidth based on a traffic decision and selectively powering off or hibernating parallel ones of the first and second internal elements.
    Type: Grant
    Filed: April 2, 2012
    Date of Patent: July 15, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Junqiang Hu, Dayou Qian, Ting Wang
  • Publication number: 20140147112
    Abstract: In order to provide a transmission device which can resolve the deterioration in transmission characteristics due to lack of the resolution of a D/A converter in a high speed and large capacity digital communication, a transmission device according to an exemplary aspect of the present invention includes an encoding unit encoding input data; an unequal-interval quantization unit quantizing an output signal from the encoding unit by a quantization level number based on a resolution of a subsequent digital-to-analog conversion unit by using an unequally spaced quantization level interval based on the output signal; the digital-to-analog conversion unit converting an output signal from the unequal-interval quantization unit into an analog signal; an output level adjustment unit adjusting an output level of the digital-to-analog conversion unit so as to compensate a difference between a predetermined initial transfer function and a transfer function of the unequal-interval quantization unit; and a modulation unit
    Type: Application
    Filed: July 5, 2012
    Publication date: May 29, 2014
    Applicant: NEC CORPORATION
    Inventor: Junichi Abe
  • Publication number: 20140147119
    Abstract: An optical signal processing apparatus includes a mixer and a first optical modulator. The mixer modulates a carrier signal of a first specific frequency received from a first oscillator with an information signal to generate a subcarrier modulated signal. The first optical modulator optically modulates, with the subcarrier modulated signal received from the mixer, carrier light optically modulated by a second optical modulator at a second specific frequency received from a second oscillator to generate and output modulated carrier light.
    Type: Application
    Filed: September 4, 2013
    Publication date: May 29, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Shigeki WATANABE, Tomoyuki KATO
  • Patent number: 8737191
    Abstract: A wireless transmit/receive unit (WTRU) that may receive an asymmetrically clipped optical orthogonal frequency-division multiplexing (ACO-OFDM) signal is disclosed. The ACO-OFDM signal may include an ACO-OFDM symbol and the ACO-OFDM signal may be generated with or without a pilot or training data. Where the ACO-OFDM signal may not include a pilot or training data, the WTRU may determine a correlation minimum between a first part of N samples of the ACO-OFDM symbol and a second part of N samples of the ACO-OFDM symbol. The correlation minimum may indicate an estimated boundary of the ACO-OFDM symbol which may provide the WTRU with timing synchronization information. Where the ACO-OFDM signal may include one or more ACO-OFDM pilot symbols on one or more pilot subcarriers, the WTRU may interpret an amount of training data included in the one or more ACO-OFDM pilot symbols that may provide information for channel estimation.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: May 27, 2014
    Assignee: InterDigital Patent Holdings, Inc.
    Inventors: Martino Freda, Alpaslan Y. Demir, Joseph M. Murray
  • Publication number: 20140133859
    Abstract: A method of allocating upstream bandwidth on a network comprising mapping an integer portion of a value obtained from a grant start time into a symbol number of a data frame on a coaxial segment of the network, wherein the value comprises the grant start time in units of a length of a data frame in the coaxial segment of a network, and wherein the length of the data frame comprises a preselected number of units of time defined in an optical segment of a network; mapping a fractional portion of the value obtained from the grant start time into a subcarrier number of the data frame; and mapping a grant length into a number subcarriers of the data frame.
    Type: Application
    Filed: December 28, 2012
    Publication date: May 15, 2014
    Applicant: FUTUREWEI TECHNOLOGIES, INC.
    Inventors: Liming Fang, Jim Chen, Li Zhang
  • Publication number: 20140133860
    Abstract: This disclosure is directed to an optical transmitter arrangement 100 and a method therein producing a first RF-signal UA1 comprising a first set of data A1 carried by a subcarrier fC1, and a second RF-signal UB1 comprising a second set of data B1 carried by the subcarrier fC1. Further producing a first transform signal H(UA1) being a Hilbert Transform of the first RF-signal UA1, and a second transform signal ?H(UB1) being a Hilbert Transform of the second RF-signal UB1. In addition, modulating the optical carrier fopt with the first RF-signal UA1 and the first transform signal H(UA1), and forming a first sideband SB1 comprising the first set of data A1 at one side of the frequency f0 of the optical carrier fopt. In addition, modulating the optical carrier fopt with the second RF-signal UB1 and the second transform signal ?H(UB1), and forming a second sideband SB2 comprising the second set of data B1 at the other side of the frequency f0 of the optical carrier fopt.
    Type: Application
    Filed: June 29, 2011
    Publication date: May 15, 2014
    Applicant: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Bengt-Erik Olsson, Jonas Martensson