Including Polarization Patents (Class 398/152)
  • Patent number: 10419124
    Abstract: A method and device for optical data transmission are disclosed. Data bits are transmitted in the form of data symbols, by modulating an optical signal in dependence on the data bits and in accordance with two or more constellation schemes. The data bits are transmitted, by generating first data symbols, which represent respective sets of data bits containing an even number of data bits. The first data symbols are generated, by modulating the optical signal in accordance with a first constellation scheme. Furthermore, the data bits are transmitted, by generating second data symbols, which represent respective sets of data bits having an odd number of data bits. The second data symbols are generated, by modulating the optical signal in accordance with a second constellation scheme. The first and the second data symbols are generated at a predefined symbol rate, such that the first and the second data symbols are interleaved in time.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: September 17, 2019
    Assignee: Alcatel Lucent
    Inventors: Jeremie Renaudier, Rafael Rios Muller, Gabriel Charlet
  • Patent number: 10408049
    Abstract: Systems, methods, and computer-readable media for providing adaptive feedback in downhole telemetry in a wellbore. A feedback system includes a source assembly, which can be located on the surface or downhole, and a receiving assembly, which can likewise be located on the surface or downhole. The source assembly includes a source device that transmits a light signal having a first phase, and an encoder coupled to the source device. The receiving assembly comprising an oscillator that transmits an oscillator having a second phase, a coupler that couples the light signal with the oscillator signal, a detector and difference amplifier that detect and determine the difference between the first phase and second phase and a processor that receives the difference between the phases and provides the difference to an encoder so that the encoder can adjust the oscillator phase.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: September 10, 2019
    Assignee: HALLIBURTON ENERGY SERVICES, INC.
    Inventors: Satyan Gopal Bhongale, Daniel Joshua Stark
  • Patent number: 10396902
    Abstract: A method of data symbol recovery in a coherent receiver of an optical communications system includes processing data symbol estimates detected from a received optical signal, and determining recovered symbol values from the processed data symbol estimates. The recovered symbol values belong to a symbol constellation having a predetermined asymmetry. Processing the data symbol estimates compensates phase noise that is greater than one decision region of the symbol constellation. A coherent receiver of an optical communications system includes a module configured to process data symbol estimates detected from a received optical signal and a decision circuit configured to determine recovered symbol values from the processed data symbol estimates. The recovered symbol values belong to a symbol constellation having a predetermined asymmetry. Processing the data symbol estimates compensates phase noise that is greater than one decision region of the symbol constellation.
    Type: Grant
    Filed: September 19, 2016
    Date of Patent: August 27, 2019
    Assignee: Ciena Corporation
    Inventors: Shahab Oveis Gharan, Kim B. Roberts, Mahmoud Taherzadehboroujeni, Amir Khandani, Akbar Ghasemi
  • Patent number: 10365126
    Abstract: A distributed optical fiber disturbance positioning system based on the asymmetric dual Mach-Zehnder interference, unlike traditional dual Mach-Zehnder distributed optical fiber disturbance sensing system, the present invention adopts two narrow-bandwidth optical sources (1a, 1b) and adopts corresponding DWDM (3a, 3b) before the detector (4a, 4b) to filter the backscatter noise of the optical fiber, and can solve the problems of having too low SNR due to backscatter influence when the sensing distance is long. The present invention also provides a positioning method for applying the system, which obtains the TFD of the disturbance frame signals by using the time-frequency analysis method based on the short-term average frequency, and takes the points near the point of maximum frequency as the effective signal segment for performing cross-correlation time delay estimation, thus obtaining the delay, and the disturbance position.
    Type: Grant
    Filed: October 27, 2016
    Date of Patent: July 30, 2019
    Assignee: Tianjin University
    Inventors: Kun Liu, Tiegen Liu, Junfeng Jiang, Chunyu Ma, Tianjiao Chai, Chang He, Miao Tian, Zhichen Li
  • Patent number: 10320602
    Abstract: A data processing method and an apparatus, where the method includes receiving m data streams using m receive ports respectively, where the m data streams include m×m data units, and the m×m data units form an m-order matrix A, keeping a location of one element in each row in the matrix A unchanged and moving remaining m?1 elements to remaining m?1 rows respectively in order to form an m-order matrix B, where a column number of each element in the remaining m?1 elements in the matrix A before the element is moved equals a column number of the element in the remaining m?1 elements in the matrix B after the element is moved, and sending using m transmit ports, the m×m elements in the matrix B to m different levels of a pulse amplitude modulation (PAM) circuit respectively for performing modulation.
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: June 11, 2019
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Wenbin Yang, Xinyuan Wang, Tongtong Wang
  • Patent number: 10205535
    Abstract: An optical IQ demodulator that does not require a power-consuming DSP is disclosed. A DC offset is added to one of the I and Q optical signal components at an IQ transmitter. After mixing with an LO signal and differential detection at the receiver, this DC offset results in a heterodyne-frequency tone in each of the quadrature detection channels of the receiver. The phase of this oscillation is recovered using a PLL circuit, which output is used to separate the transmitter I and Q channels for decoding thereof using conventional electronics.
    Type: Grant
    Filed: December 14, 2017
    Date of Patent: February 12, 2019
    Assignee: Elenion Technologies, LLC
    Inventor: Thomas Wetteland Baehr-Jones
  • Patent number: 10187174
    Abstract: An optical reception apparatus (1) of the present invention includes: a local oscillator (11) outputting local oscillation light (22); an optical mixer (12) receiving a multiplexed optical signal (21) and the local oscillation light, and selectively outputting an optical signal (23) corresponding to the wavelength of the local oscillation light from the multiplexed optical signal; a photoelectric converter (13) converting the optical signal (23) output from the optical mixer into an electric signal (24); a variable gain amplifier (15) amplifying the electric signal (24) to generate an output signal (25) whose output amplitude is amplified to a certain level; a gain control signal generating circuit (16) generating a gain control signal (26) for controlling the gain of the variable gain amplifier (15); and a monitor signal generating unit (17) generating a monitor signal (27) corresponding to the power of the optical signal (23) using the gain control signal (26).
    Type: Grant
    Filed: May 22, 2017
    Date of Patent: January 22, 2019
    Assignee: NEC Corporation
    Inventor: Yusuke Yamauchi
  • Patent number: 10185104
    Abstract: A method of assembling an optical module that recovers data by interfering signal light with local light is disclosed. The optical module provides a housing with a side to which a signal port and a local port are fixed, and an optical components having a light incident surface whose normal makes an angle ? except for 0° and 90° against the axis of the signal port. The method first adjusts a rotation of the assembling apparatus by (1) setting a tool on the apparatus, where the tool has a pair of sides parallel to each other and a reference side making the angle ? against one of the paired sides, and (2) facing the reference side toward the preset direction. Next, setting the housing on the apparatus in an attitude same with the tool and facing the optical component toward the preset direction above the housing, the process installs the optical component within the housing.
    Type: Grant
    Filed: November 25, 2016
    Date of Patent: January 22, 2019
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasushi Fujimura, Munetaka Kurokawa, Tomoya Saeki
  • Patent number: 10135536
    Abstract: A transceiver having an improved transmitter optical signal to noise ratio, and methods of making and using the same.
    Type: Grant
    Filed: January 13, 2017
    Date of Patent: November 20, 2018
    Assignee: Elenion Technologies, LLC
    Inventors: Guido Saathoff, Matthew Akio Streshinsky, Robert Palmer, Torsten Wuth
  • Patent number: 10056981
    Abstract: A receiver for fiber optic communications.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: August 21, 2018
    Assignee: INPHI CORPORATION
    Inventors: Oscar Ernesto Agazzi, Diego Ernesto Crivelli, Hugo Santiago Carrer, Mario Rafael Hueda, Martin Ignacio Del Barco, Pablo Gianni, Ariel Pola, Elvio Adrian Serrano, Alfredo Javier Taddei, Mario Alejandro Castrillon, Martin Serra, Ramiro Matteoda
  • Patent number: 10044439
    Abstract: An optical receiver includes a processor. The processor calculates first through fourth optical intensities that respectively indicate input optical intensities of in-phase component in the first polarization, quadrature component in the first polarization, in-phase component in the second polarization and quadrature component in the second polarization. The processor calculates polarization dependent intensity ratio and phase dependent intensity ratio based on the first through fourth optical intensities. The processor calculates an input optical intensity of a polarization multiplexed optical signal based on an optical intensity of one of the first through fourth amplifiers, the polarization dependent intensity ratio, and the phase dependent intensity ratio.
    Type: Grant
    Filed: October 3, 2017
    Date of Patent: August 7, 2018
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Masayuki Kurisu, Shuichi Yasuda
  • Patent number: 10024798
    Abstract: A hyperspectral Raman imaging system having the ability to focus on excitation laser beam over a relatively wide field of view due to the use of a lens array, in particular a microlens array. Hyperspectral selection is provided in one embodiment through the use of dual-axis controlled dielectric filtration. Methods for analyzing materials with the system are disclosed. The device or system can be used in generally any application where investigation of materials is required.
    Type: Grant
    Filed: January 20, 2015
    Date of Patent: July 17, 2018
    Assignee: CASE WESTERN RESERVE UNIVERSITY
    Inventors: Ozan Akkus, Shan Yang
  • Patent number: 10014952
    Abstract: The present disclosure relates to a method for decoding a combined AM/FM encoded signal, comprising the steps of: combining said encoded optical signal with light from a local oscillator configured with a local oscillator frequency; converting the combined local oscillator and encoded optical signal into one or more electrical signals by means of at least one opto-electrical converter having a predefined frequency bandwidth, thereby providing an amplified and encoded electrical signal having one or more encoded signal current(s), where one type of states have a higher oscillation frequency than other type of states; rectifying the encoded signal current(s), thereby obtaining an encoded power spectrum, wherein said power spectrum has different states, such as “0”-states and “1”-states, with different power levels such that they can be discriminated, said local oscillator frequency is defined by a positive local oscillator frequency-offset from the frequency of one of the states in said encoded optical signal,
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: July 3, 2018
    Assignee: DANMARKS TEKNISKE UNIVERSITET
    Inventors: Jesper Bevensee Jensen, Bo Pedersen, Roberto Rodes Lopez
  • Patent number: 10009114
    Abstract: A method of generating a signal being phase-shifted at a predetermined phase-shift division factor relative to a reference signal is disclosed. The method comprises: using the predetermined phase-shift division factor for selecting a modulation amplitude, modulating a control signal at the selected modulation amplitude, and combining the reference signal and the control signal to form the phase-shifted.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: June 26, 2018
    Assignee: Ariel-University Research and Development Company Ltd.
    Inventors: Shmuel Sternklar, Moran Biton
  • Patent number: 10003408
    Abstract: A receiver device and receiving method for a coherent optical communication system are disclosed. The disclosed device includes: an optical splitter configured to split a received optical signal into at least two paths; a first amplifier configured to amplify a second optical signal from among a first optical signal and the second optical signal split into two paths; a second amplifier configured to amplify the output signal of the first amplifier; and a coherent receiver module configured to mix and detect the output signal of the second amplifier and the first optical signal. The disclosed device provides the advantages of suppressing the occurrence of frequency offsets and minimizing phase noise, as well as allowing manufacture with a low cost without requiring either an additional optical source or additional optical fibers.
    Type: Grant
    Filed: January 19, 2016
    Date of Patent: June 19, 2018
    Assignee: INDUSTRY-ACADEMIC COOPERATION FOUNDATION, YONSEI UNIVERSITY
    Inventors: Sang Kook Han, Kyoung Hak Mun
  • Patent number: 9973280
    Abstract: A digital signal processor (DSP) may include a receiver configured to receive an input signal. The DSP may include a processor component to perform carrier recovery on a set of digital signals representing a set of symbols associated with the input signal. The DSP may include an output component to provide information included in the set of digital signals representing the set of symbols. The DSP may be configured to perform, for the input signal, phase estimation with a latency of less than approximately 880 nanoseconds and having a power consumption of less than approximately 400 milliwatts at an update rate greater than approximately 4 Gigahertz. The latency being a propagation delay of the input signal.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: May 15, 2018
    Assignee: Infinera Corporation
    Inventors: Ahmed Awadalla, Han Sun, Kuang-Tsan Wu
  • Patent number: 9967036
    Abstract: This disclosure describes techniques to sample electrical data streams in coherent receivers. For instance, an analog-to-digital converter (ADC) samples the received electrical data stream at a sampling rate that is nominally twice or greater than twice the symbol rate of the electrical data stream that the ADC receives. A digital filter receives the digital data stream from the ADC, and digitally filters the digital data streams to output a filtered digital electrical data stream at an effective sampling rate that is less than the sampling rate and less than twice the symbol rate, and greater than or equal to the symbol rate.
    Type: Grant
    Filed: April 29, 2015
    Date of Patent: May 8, 2018
    Assignee: Juniper Networks, Inc.
    Inventors: Christian Malouin, Theodore John Schmidt, Bo Zhang, Elias Simpson, Roberto Marcoccia
  • Patent number: 9960855
    Abstract: A receiver for fiber optic communications.
    Type: Grant
    Filed: October 17, 2017
    Date of Patent: May 1, 2018
    Assignee: INPHI CORPORATION
    Inventors: Oscar Ernesto Agazzi, Diego Ernesto Crivelli, Hugo Santiago Carrer, Mario Rafael Hueda, Martin Ignacio Del Barco, Pablo Gianni, Ariel Pola, Elvio Adrian Serrano, Alfredo Javier Taddei, Mario Alejandro Castrillon, Martin Serra, Ramiro Matteoda
  • Patent number: 9952482
    Abstract: There is presented an optical apparatus comprising first and second photon pair sources configured to convert at least one pump light photon into a first and second correlated signal and idler photon pairs. In one example, the apparatus is configured to use one of the signal and idler photons from the first correlated photon pair for controlling the conversion of the pump light photon in the second photon pair source. The apparatus may configured such that, at least one of the signal and idler photons from the first correlated photon pair is output from the first photon pair source onto an optical path wherein at least one of the signal and idler photons from the second correlated photon pair is output from the second photon pair source onto the optical path. A method is also provided for outputting one or more photons using the optical apparatus.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: April 24, 2018
    Assignee: The University of Bristol
    Inventors: Terence Rudolph, Mark Thompson, Jonathan Matthews, Damien Bonneau
  • Patent number: 9882647
    Abstract: An optical transmission apparatus includes: a coherent detector configured to receive light including different polarization components from an optical transmission path, and perform coherent detection of received light including the different polarization components; an adaptive equalizer configured to adaptively equalize, by a digital filter, a complex electric signal for each of the polarization components obtained by the coherent detection, a gain value for controlling an amplitude of the complex electric signal being applied to the complex electric signal; and a polarization dependent loss monitor configured to determine a polarization dependent loss of the optical transmission path, based on a correction filter parameter obtained by correcting a filter parameter of the digital filter according to the gain value, the filter parameter being adaptively updated by an adaptive equalization of the adaptive equalizer.
    Type: Grant
    Filed: February 2, 2016
    Date of Patent: January 30, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Taketo Endo, Kosuke Komaki, Taku Saito, Hirofumi Araki, Makoto Shimizu, Hiroshi Nishida
  • Patent number: 9825711
    Abstract: A receiver for fiber optic communications.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: November 21, 2017
    Assignee: INPHI CORPORATION
    Inventors: Oscar Ernesto Agazzi, Diego Ernesto Crivelli, Hugo Santiago Carrer, Mario Rafael Hueda, Martin Ignacio del Barco, Pablo Gianni, Ariel Pola, Elvio Adrian Serrano, Alfredo Javier Taddei, Mario Alejandro Castrillon, Martin Serra, Ramiro Matteoda
  • Patent number: 9800396
    Abstract: The present invention relates to a transmitter and a receiver including multiple first and second transceiving units. Each of the first and the second transceiving units includes a first and a second radiation slices and a first and a second transceiving circuits disposed thereon. In the transmitter, the first and the second transceiving units receive first and second internal transmission signals at first and second polarization from the first and the second radiation slices, and transmit first and second external transmission signals generated from transformation through the first and the second radiation slices. In the receiver, the first and the second transceiving units receive first and second external reception signals at first and second polarization through the first and the second radiation slices, and transmit first and second internal reception signals at first and second polarization generated from transformation through the first and the second radiation slices.
    Type: Grant
    Filed: December 23, 2016
    Date of Patent: October 24, 2017
    Assignee: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Fang-Yao Kuo, Che-Yang Chiang, Shih-Chieh Yen, Wen-Chiang Chen
  • Patent number: 9798415
    Abstract: According to one embodiment, a display device includes a plurality of display elements arranged in a matrix, a plurality of scanning lines, a plurality of signal lines, and a controller configured to control display by sequentially supplying an image signal and a control signal to the plurality of signal lines and the plurality of scanning lines, respectively, wherein the controller repeats a display period in which the display is controlled and a display blanking period in which the display is paused to display a frame image, and at least two types of display periods with different lengths are used when a frame image is displayed.
    Type: Grant
    Filed: September 11, 2015
    Date of Patent: October 24, 2017
    Assignee: Japan Display Inc.
    Inventors: Kohei Azumi, Hidetoshi Komatsu, Jin Ota, Hiroshi Mizuhashi
  • Patent number: 9793999
    Abstract: A novel digital signal processing scheme (DSP) for quadrature duobinary (QDB) spectrum shaped polarization multiplexed quadrature phase shift keying (PM-QPSK) based on multi-modulus blind equalizations (MMBE) is proposed and demonstrated with both simulation and experimental results. The key algorithms for this novel digital signal processing scheme include the cascaded multi-modulus algorithm (CMMA) for blind polarization de-multiplexing, multi-modulus QPSK partitioning frequency offset estimation (FOE) and two stage carrier phase recovery (CPR) with maximum likelihood phase estimation. The final signal is detected by maximum-likelihood sequence detection (MLSD) for data BER measurement. The feasibility of the proposed digital signal processing scheme is demonstrated by the experiment of 112 Gb/s QDB spectrum shaped PM-QPSK signal with a 25 GHz bandwidth waveshaper for Nyquist WDM channels.
    Type: Grant
    Filed: August 15, 2013
    Date of Patent: October 17, 2017
    Assignee: ZTE Corporation
    Inventors: Jianjun Yu, Ze Dong, Hung-Chang Chien
  • Patent number: 9729247
    Abstract: A light transmitter to transmit multiple light packets, each formatted to include a same message comprising a series of bits, each bit represented as light that is intensity modulated over a bit period at a frequency indicative of the bit. The light packets are transmitted at different start-times to establish different phases, one for each of the light packets, to permit a light receiver to sample each message at a different phase of a fixed sample timeline that is asynchronous to the bit period and the frequency. The light receiver samples the multiple light packets based on the sample timeline, to sample each received message at one of the different sample phases, then constructs a best series of bits based on the multiple demodulated messages.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: August 8, 2017
    Assignee: INTEL CORPORATION
    Inventors: Richard D. Roberts, Mathys C. Walma, Praveen Gopalakrishnan
  • Patent number: 9680574
    Abstract: An optical transceiver in an optical communications network, comprising a receiver configured to receive an optical signal comprising an X-polarization component that comprises a first frame and a Y-polarization component that comprises a second frame. The optical transceiver also comprises a processor coupled to the receiver and configured to determine, in a time domain, a phase estimate according to the first frame and the second frame, determine, in a frequency domain, a channel estimate for the optical signal according to a relationship between the first frame, the second frame, and the phase estimate, and determine a compensated optical signal according to the channel estimate. The optical transceiver further comprises a transmitter coupled to the processor and configured to transmit the compensated optical signal to a downstream component in the optical communications network.
    Type: Grant
    Filed: November 30, 2015
    Date of Patent: June 13, 2017
    Assignee: Futurewei Technologies, Inc.
    Inventors: Murali Krishnan, Qing Guo, Samina Chowdhury, Fei Zhu, Yu Sheng Bai
  • Patent number: 9680598
    Abstract: A wavelength division multiplexing optical transmission apparatus includes a plurality of polarization multiplexing optical modulation means, polarization-maintaining optical multiplexing means, and delay adjustment means. The polarization multiplexing optical modulation means generate a plurality of polarization multiplexed optical modulation signals having different wavelengths. The polarization-maintaining optical multiplexing means multiplexes the wavelengths of the polarization multiplexed optical modulation signals to generate a wavelength multiplexed optical signal (WDM). The delay adjustment means adjusts a delay such that light intensities of polarization multiplexed optical modulation signals having adjacent wavelengths in the wavelength multiplexed optical signal (WDM) vary inversely with respect to each other.
    Type: Grant
    Filed: October 18, 2013
    Date of Patent: June 13, 2017
    Assignee: NEC Corporation
    Inventor: Yoshihisa Inada
  • Patent number: 9647753
    Abstract: A coherent optical receiver includes: an attenuator that adjusts a power of an input optical signal; a mixer that mixes an optical signal output from the attenuator and local oscillator light; a photo detector that converts an optical signal output from the mixer into an electric signal; an amplifier that amplifies an output signal of the photo detector; a gain controller that controls a gain of the amplifier; a memory that stores dependence information that indicates a relation between an input optical power of an optical signal of a specified wavelength and a gain of the amplifier; and a controller that calculates an input optical power of the target wavelength based on a gain of the amplifier and the dependence information, and controls an attenuation amount of the attenuator based on the calculated input optical power, when a WDM optical signal is input into the coherent optical receiver.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: May 9, 2017
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Masayuki Kurisu, Shuichi Yasuda, Takeyasu Tomioka
  • Patent number: 9641258
    Abstract: A receiver that may include a receiver front end arranged to receive (a) a received signal, (b) a reference signal generated by a local oscillator laser, and to output a first intermediate signal; a carrier phase estimator that is arranged to receive the first intermediate signal and to generate a phase estimation signal that represents a phase difference between the received signal and the reference signal; wherein the carrier phase estimator comprises a multi-symbol-differential-detection module and a carrier phase demodulator; and an output circuit arranged to receive the phase estimation signal and to apply a slicing operation to provide an output signal of the carrier phase estimator.
    Type: Grant
    Filed: July 2, 2015
    Date of Patent: May 2, 2017
    Assignee: TECHNION RESEARCH AND DEVELOPEMENT FOUNDATION LTD.
    Inventors: Moshe Nazarathy, Igor Tselniker, Netta Sigron
  • Patent number: 9577780
    Abstract: Methods and systems for a polarization immune wavelength division multiplexing demultiplexer are disclosed and may include, in an optoelectronic transceiver having an input coupler, a demultiplexer, and an amplitude scrambler: receiving input optical signals of different polarization via the input coupler, communicating the input optical signals to the amplitude scrambler via waveguides, configuring the average optical power in each of the waveguides utilizing the amplitude scrambler, and demultiplexing the optical signals utilizing the demultiplexer. The amplitude scrambler may include phase modulators and a coupling section. The phase modulators may include sections of P-N junctions in the two waveguides. The demultiplexer may include a Mach-Zehnder Interferometer. The demultiplexed signals may be received utilizing photodetectors. The input coupler may include a polarization splitting grating coupler.
    Type: Grant
    Filed: June 26, 2015
    Date of Patent: February 21, 2017
    Assignee: Luxtera, Inc.
    Inventor: Brian Welch
  • Patent number: 9551939
    Abstract: An apparatus to measure the position of a mark, the apparatus including an illumination arrangement to direct radiation across a pupil of the apparatus, the illumination arrangement including an illumination source to provide multiple-wavelength radiation of substantially equal polarization and a wave plate to alter the polarization of the radiation in dependency of the wavelength, such that radiation of different polarization is supplied; an objective to direct radiation on the mark using the radiation supplied by the illumination arrangement while scanning the radiation across the mark in a scanning direction; a radiation processing element to process radiation that is diffracted by the mark and received by the objective; and a detection arrangement to detect variation in an intensity of radiation output by the radiation processing element during the scanning and to calculate from the detected variation a position of the mark in at least a first direction of measurement.
    Type: Grant
    Filed: September 23, 2013
    Date of Patent: January 24, 2017
    Assignees: ASML NETHERLANDS B.V., ASML HOLDING N.V.
    Inventors: Simon Gijsbert Josephus Mathijssen, Arie Jeffrey Den Boef, Stanley Drazkiewicz, Justin Lloyd Kreuzer, Gerrit Johannes Nijmeijer
  • Patent number: 9515763
    Abstract: A digital coherent receiver that receives a first optical signal in a WDM optical signal includes: a front-end circuit configured to generate a digital signal indicating the first optical signal; a waveform distortion corrector configured to generate a correction result signal indicating a first optical signal whose waveform distortion has been corrected by performing a digital arithmetic operation on the digital signal using at least one dispersion compensators and at least one nonlinear compensators; and a controller configured to adjust operation states of specified dispersion compensators among the plurality of dispersion compensators and specified nonlinear compensators among the plurality of nonlinear compensators. The number of the specified dispersion compensators and the number of the specified nonlinear compensators are determined based on the number of spans of an optical transmission line through which the first optical signal is transmitted.
    Type: Grant
    Filed: March 18, 2015
    Date of Patent: December 6, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Toshiki Honda, Takeshi Hoshida
  • Patent number: 9497048
    Abstract: The present disclosure provides a method and system for fine estimation of a local oscillator frequency offset of a received signal at a coherent receiver, by evaluating the probability mass function (PMF) of the signal phase of output symbols at different frequencies. At frequencies other than the actual frequency offset, the signal phase is uniformly distributed in [??,?] such that the summation of a function of PMF values where the function is convex or concave between 0 and 1 can be utilized to determine an a frequency offset to be used by the coherent receiver.
    Type: Grant
    Filed: December 22, 2015
    Date of Patent: November 15, 2016
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Mahdi Zamani, Zhuhong Zhang, Chuandong Li
  • Patent number: 9490875
    Abstract: Techniques are described herein for filtering and/or otherwise isolating or extracting components of multi-component signals. More specifically, embodiments of the present disclosure describe techniques for filtering and/or otherwise extracting a continuous wave component (or wireless power component) and a modulated data component from a multi-component signal. In some embodiments, the techniques describe systems, apparatuses and methods for filtering and/or otherwise isolating or extracting a frequency (e.g., modulated data component) from a continuous wave (e.g., wireless power component) without affecting the levels of other frequencies. The individual components or signals can be transmitted by one or more sources and received at one or more existing antennas of an electronic device simultaneously.
    Type: Grant
    Filed: October 29, 2015
    Date of Patent: November 8, 2016
    Assignee: Ossia Inc.
    Inventors: Prithvi Shylendra, Anthony L. Johnson, Hatem Zeine, Douglas Wayne Williams
  • Patent number: 9473250
    Abstract: The embodiments of the invention provide methods to deal with problems of cycle slips, angular skew, and residual phase noise for high-speed optical communications employing any arbitrary high-order multi-dimensional modulation formats. The embodiments use a slip process analyzer, a skew angle estimator, and a phase noise variance estimator to provide feedforward soft-decision information of a carrier phase recovery (CPE) for more accurate likelihood calculation based on a high-order hidden Markov model (HMM). The log-likelihood calculation can be done jointly in dual polarization with joint Markov state transition. Some embodiments use a kernel filter or a particle filter for log-likelihood calculation.
    Type: Grant
    Filed: September 3, 2014
    Date of Patent: October 18, 2016
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Toshiaki Koike-Akino, Keisuke Kojima, David Millar
  • Patent number: 9444554
    Abstract: A digital coherent receiving apparatus includes a first oscillator for outputting a local light signal of a fixed frequency, a hybrid unit mixing the local light signal with a light signal received by a receiver, a second oscillator for outputting a sampling signal of a sampling frequency, a converter for converting the mixed light signal into digital signal synchronizing with the sampling signal, a waveform adjuster for adjusting a waveform distortion of the converted digital signal, a phase adjustor for adjusting a phase of the digital signal adjusted by the waveform adjustor, a demodulator for demodulating the digital signal adjusted by the phase adjuster, and a phase detector for detecting a phase of the digital signal adjusted by the phase adjuster, and a control signal output unit for outputting a frequency control signal on the basis of the detected phase signal to the second oscillator.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: September 13, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Nobukazu Koizumi, Takeshi Hoshida, Takahito Tanimura, Hisao Nakashima, Koji Nakamuta, Noriyasu Nakayama
  • Patent number: 9438371
    Abstract: A method of optical communication comprising encoding four modulated symbols to generate four encoded symbols in two orthogonal polarizations and transmitting the four encoded symbols in two successive time slots. An optical communication apparatus comprising a processor configured to receive two sequences of digital symbols in a plurality of time slots, wherein the two sequences correspond to two components of two orthogonal polarizations, wherein one digital symbol per polarization is received in each of the plurality of time slots, divide each of the two sequences into a plurality of groups using a modulo operation of time, wherein each group comprises two digital symbols received in two consecutive time slots, and adaptively equalize the four digital symbols of the two consecutive time slots using a 4×4 matrix to generate four modulated symbols, wherein the 4×4 matrix comprises 16 tap-vectors.
    Type: Grant
    Filed: December 4, 2015
    Date of Patent: September 6, 2016
    Assignee: Futurewei Technologies, Inc.
    Inventors: Mahdi Zamani, Chuandong Li, Zhuhong Zhang
  • Patent number: 9438348
    Abstract: We disclose communication methods using which a cluster of network nodes is interconnected via an optical interconnect and an electrical switch engine. A communication method executed at a master optical transceiver coupled to one side of the optical interconnect enables that transceiver to establish an optical communication link with any one of a plurality of slave optical transceivers coupled to the other side of the optical interconnect. A communication method executed at a slave optical transceiver enables that transceiver to communicate with the master optical transceivers without having its own light source and, instead, modulating data onto previously un-modulated signaling dimensions of the incoming optical waveforms, which are then turned around and broadcast back to the master optical transceivers.
    Type: Grant
    Filed: November 6, 2014
    Date of Patent: September 6, 2016
    Assignee: Alcatel Lucent
    Inventor: Joseph K. Kakande
  • Patent number: 9426000
    Abstract: System and method for equalizing a high bit rate optical communication channel in a symbol spaced adaptive Multiple-In-Multiple-Out (MIMO) system, where the optical communication channel carries a signal that is sampled at a symbol rate. Accordingly, Anti Aliasing Filtering (which introduces distortions in the form of Deterministic Inter Symbol Interference D-ISI) is applied in a MIMO channel, in order to reduce the aliasing effect associated with symbol rate sampling. The Polarization Mode Dispersions introduced in the optical communication channel are solely compensated by a MIMO Equalizer, which ignores the Deterministic ISI (D-ISI) distortion. Then the Deterministic ISI (D-ISI) distortion is solely compensated by an independent Deterministic Equalizer (DE).
    Type: Grant
    Filed: January 2, 2013
    Date of Patent: August 23, 2016
    Assignee: Multiply Ltd.
    Inventors: Albert Gorshtein, Dan Sadot
  • Patent number: 9391715
    Abstract: A receiver for fiber optic communications.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: July 12, 2016
    Assignee: ClariPhy Communications, Inc.
    Inventors: Oscar Ernesto Agazzi, Diego Ernesto Crivelli, Hugo Santiago Carrer, Mario Rafael Hueda, Martin Ignacio del Barco, Pablo Gianni, Ariel Pola, Elvio Adrian Serrano, Alfredo Javier Taddei, Mario Alejandro Castrillon, Martin Serra, Ramiro Matteoda
  • Patent number: 9385815
    Abstract: In some examples, a transmit assembly is described that may include a first optical transmitter, a second optical transmitter, and a polarizing beam combiner. The first optical transmitter may be configured to emit a first optical data signal centered at a first frequency. The second optical transmitter may be configured to emit a second optical data signal centered at a second frequency offset from the first frequency by a nominal offset n. The polarizing beam combiner may be configured to generate a dual carrier optical data signal by polarization interleaving the first optical data signal with the second optical data signal. An output of the polarizing beam combiner may be configured to be communicatively coupled via an optical transmission medium to a polarization-insensitive receive assembly.
    Type: Grant
    Filed: February 9, 2015
    Date of Patent: July 5, 2016
    Assignee: FINISAR CORPORATION
    Inventors: Ilya Lyubomirsky, Yasuhiro Matsui, Daniel Mahgerefteh
  • Patent number: 9348194
    Abstract: A light pulse source (100), being adapted for generating repetitive optical pulses, comprises a continuous wave (cw) laser (10) being arranged for providing cw laser light, an optical microresonator (20) being made of a resonator material, which has a third order (Kerr) nonlinearity and an anomalous resonator dispersion, wherein the cw laser (10) is arranged for coupling the cw laser light into the optical microresonator (20), which, at a predetermined relative detuning of the cw laser (10) and the optical microresonator (20), is capable of including a light field in a soliton state, wherein soliton shaped pulses can be coupled out of the optical microresonator (20) for providing the repetitive optical pulses, and a tuning device (30) being arranged for creating and maintaining the predetermined relative detuning of the cw laser (10) and the optical microresonator (20) based on a tuning time profile being selected in dependency on a thermal time constant of the optical microresonator (20) such that the solito
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: May 24, 2016
    Assignee: Ecole Polytechnique Federale de Lausanne (EPFL)
    Inventors: Tobias Herr, Michael L. Gorodetsky, Tobias Kippenberg
  • Patent number: 9281903
    Abstract: A received optical signal is coherently demodulated and converted into electrical complex samples (p(n); (px(n), py(n)), which are dispersion compensated in a compensation filter (11). A control circuit (12, 13, 14, 15) calculates comparison values (R1, R2) from corrected samples q(n) and an estimated error value (?MIN). A plurality of compensation function (T(M)) is applied according to a predetermined dispersion (CD) range and after a second iteration is the compensation filter (11) set to an optimum compensation function (T(M)).
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: March 8, 2016
    Assignee: Xieon Networks S.a.r.l.
    Inventors: Fabian Hauske, Maxim Kuschnerov, Berthold Lankl, Bernhard Spinnler
  • Patent number: 9264146
    Abstract: Embodiments of the disclosure include a method and apparatus for detecting and removing cycle slip. A phase-modulated signal having a plurality of phase-modulated symbols is received at an optical receiver, and, for each phase-modulated symbol, a phase-error estimate of a phase error of the phase-modulated symbol is generated. The presence of a cycle slip is then detected based on the phase-error estimates, and, a phase of each of one or more of the received phase-modulated symbols is adjusted to remove the detected cycle slip without adjusting a local oscillator.
    Type: Grant
    Filed: January 30, 2014
    Date of Patent: February 16, 2016
    Assignee: Alcatel Lucent
    Inventors: Xiang Liu, Chandrasekhar Sethumadhavan, Timo Pfau, Giancarlo Gavioli
  • Patent number: 9256013
    Abstract: A SWIR hyperspectral imaging filter has serial stages along an optical signal path with angularly distributed birefringent retarders and polarizers. The retarders can include active retarders such as tunable liquid crystal birefringent elements, passive retarders such as fixed retarders, and/or combinations thereof. Distinctly different periodic transmission spectra are provided by different filter stages, each having multiple retarders, in particular with some stages having broad bandpass peaks at wide spectral spacing and other stages have very narrow closely spaced peaks. The respective spectra include at least one tunably selectable band at which the transmission spectra of the filter stages coincide, whereby the salutary narrow bandpass and wide spectral spacing ranges of different stages apply together, resulting in a high finesse wavelength filter suitable for spectral imaging.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: February 9, 2016
    Assignee: ChemImage Technologies LLC
    Inventors: Lei Shi, George Ventouris, Thomas Voigt
  • Patent number: 9236951
    Abstract: An optical signal (116) is modulated with a transmitted electrical signal comprising an information-bearing component (122) and a pilot tone (120) having a predetermined frequency. Transmission of the signal results in distortion, including nonlinear optical transmission impairments. A method of receiving the signal includes detecting the optical signal to produce a received electrical signal (X) comprising a distorted variant of the transmitted electrical signal. The pilot tone is extracted from the received electrical signal using a filtering operation (308) having a predetermined characteristic, and a compensation signal determined based upon the extracted pilot tone. The compensation signal is applied to the received electrical signal (X) to produce a compensated signal (Y) having reduced distortion.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: January 12, 2016
    Assignee: OFIDIUM PTY. LTD.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 9236973
    Abstract: A method of optical communication comprising encoding four modulated symbols to generate four encoded symbols in two orthogonal polarizations and transmitting the four encoded symbols in two successive time slots. An optical communication apparatus comprising a processor configured to receive two sequences of digital symbols in a plurality of time slots, wherein the two sequences correspond to two components of two orthogonal polarizations, wherein one digital symbol per polarization is received in each of the plurality of time slots, divide each of the two sequences into a plurality of groups using a modulo operation of time, wherein each group comprises two digital symbols received in two consecutive time slots, and adaptively equalize the four digital symbols of the two consecutive time slots using a 4×4 matrix to generate four modulated symbols, wherein the 4×4 matrix comprises 16 tap-vectors.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: January 12, 2016
    Assignee: Futurewei Technologies, Inc.
    Inventors: Mahdi Zamani, Chuandong Li, Zhuhong Zhang
  • Patent number: 9219551
    Abstract: Proposed is a method of demodulating a phase modulated optical signal received from an optical channel. A time-discrete electrical signal is derived from the phase modulated optical signal, using a local optical signal, which has a frequency that is essentially equal to a carrier frequency of the phase modulated optical signal. A phase error between the local optical signal and the phase modulated optical signal is compensated, by deriving from the local optical signal a phase offset and modifying the derived time-discrete electrical signal by this phase offset. A chromatic dispersion caused by the optical channel is compensated, by filtering the modified time-discrete electrical signal using a digital filter.
    Type: Grant
    Filed: June 20, 2012
    Date of Patent: December 22, 2015
    Assignee: Alcatel Lucent
    Inventors: Francesco Vacondio, Oriol Bertran-Pardo
  • Patent number: 9143154
    Abstract: To that end, it is an object of the invention to provide a method for converting a high-speed digital signal in the form of optical pulses intended to be transmitted within optical guides, within which the signal is converted into a series of optical pulses in three possible phase states (?/6, 5?/6, ??/2) separated from one another two-by-two by an angle greater than ?/2.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: September 22, 2015
    Assignee: Alcatel Lucent
    Inventors: Gabriel Charlet, Jeremie Renaudier
  • Patent number: 9083471
    Abstract: A receiver and a multi-symbol-differential-detection (MSDD) module, the MSDD may include an input node for receiving an input signal having a noisy phase; a summation and rotation unit; and an output unit; wherein the output unit is arranged to output an output signal and a normalized output signal; wherein the output signal represents the input signal but has a reconstructed phase; wherein the summation and rotation unit is arranged to receive the input signal and the output signal and to provide a reference signal that reflects a weighted sum of phase rotated and delayed previously received input signals; wherein the output unit comprises a phase difference calculator, a slicer, a delay unit and a normalizer; wherein the phase difference calculator is arranged to generate a difference signal indicative of a phase difference between the reference signal and the input signal; wherein the slicer and the delay unit are arranged to generate the output signal by slicing the difference signal to provide a sliced s
    Type: Grant
    Filed: March 1, 2012
    Date of Patent: July 14, 2015
    Assignee: TECHNION RESEARCH AND DEVELOPMENT FOUNDATION LTD.
    Inventors: Igor Tselniker, Netta Sigron, Moshe Nazarathy