Phase Modulation Patents (Class 398/188)
  • Patent number: 10397546
    Abstract: Apparatus for controlling a plurality of active illumination range cameras to operate in a time division multiplexed operating mode to acquire range images of scenes that the cameras image.
    Type: Grant
    Filed: September 30, 2015
    Date of Patent: August 27, 2019
    Assignee: Microsoft Technology Licensing, LLC
    Inventor: Abhinav Kashyap
  • Patent number: 10313021
    Abstract: An optical transceiver includes an optical transmitter configured with data pre-coding to support integrating and resetting functions in a corresponding self-resetting integrating optical receiver; and a self-resetting integrating optical receiver comprising dual photodetectors connected to a capacitor, wherein the dual photodetectors and the capacitor are configured to perform the integrating and resetting functions based on a pre-coded optical input from a corresponding optical transmitter. The data pre-coding can include a 0 differential phase indicative of a 1 bit to set a charge on the capacitor for setting function, +/??/2 differential phase indicative of a hold so that the charge on the capacitor is held at a previous value by delivering equal intensity to the dual photodetectors for a holding function, and a ? differential phase indicative of a 0 bit to reset the charge on the capacitor to zero for resetting function.
    Type: Grant
    Filed: January 10, 2018
    Date of Patent: June 4, 2019
    Assignee: Ciena Corporation
    Inventors: Michael Y. Frankel, Vladimir Pelekhaty
  • Patent number: 10263708
    Abstract: Disclosed herein is a dual parallel Mach-Zehnder-modulator (DPMZM) device comprising a DPMZM 10 having first and second inner MZMs arranged parallel to each other. The first inner MZM generates an in-phase component EI of an optical signal in response to a first driving voltage VI, and the second inner MZM generates a quadrature component EQ of said optical signal in response to a second driving voltage VQ. Further disclosed is a calculation unit 52 configured for receiving an in-phase component yI and a quadrature component yQ_ of a desired base-band signal, and for calculating pre-distorted first and second driving voltages VI, VQ. The calculation of the pre-distorted first and second driving voltages VI, VQ is based on a model of said DPMZM 10 accounting for I-Q cross-talk, and using an algorithm that determines said first and second driving voltages VI, VQ each as a function of both of said in-phase and quadrature components yI, yQ of said base-band signal.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: April 16, 2019
    Assignee: Xieon Networks S.à.r.l.
    Inventors: Alessandro Bianciotto, Stefano Calabro, Maxim Kuschnerov, Mahdi Mezghanni, Antonio Napoli, Bernhard Spinnler
  • Patent number: 10263707
    Abstract: Embodiments of the present disclosure are directed toward techniques and configurations for an apparatus comprising an electro-optical modulation device with a bias control and adjustment. In some embodiments, the apparatus may comprise an electro-optical modulator having first and second arms, to modulate light passing through the first and second arms in response to an input data signal, and output a corresponding optical data signal. The apparatus may further comprise a control module coupled with the electro-optical modulator, to differentially adjust respective phases of first or second light portions passing through the first and second arms, to achieve a bias point for the optical data signal. The bias point may define a desired power output of the apparatus that corresponds to the optical data signal. Other embodiments may be described and/or claimed.
    Type: Grant
    Filed: September 22, 2015
    Date of Patent: April 16, 2019
    Assignee: Intel Corporation
    Inventors: Thiruvikraman Vikram Sadagopan, Sang Yup Kim, Jen-Chyun Chen
  • Patent number: 10211928
    Abstract: Constant modulus multi-dimensional modulation system and methods are disclosed herein, employing multi-intensity quadrature amplitude modulation (QAM) to generate a dual-polarization symbol. j bits may be mapped to one of a plurality of dual-polarization symbols having a same constant power modulus on a two-level constellation including first and second intensity rings in a four-dimensional (4D) space including in-phase (I), quadrature (Q), X polarization (Xpol) and Y polarization (Ypol). A first bit of the j bits may indicate that the symbol is on the first intensity ring for the Xpol and the second intensity ring for the Ypol, a next k bits may indicate a location of the symbol on the first intensity ring in the Xpol, and a remaining j?k?1 bits may indicate a location of the symbol on the second intensity ring in the Ypol. Maximum correlation decoding may be used to decode the first symbol at the receiver.
    Type: Grant
    Filed: March 19, 2018
    Date of Patent: February 19, 2019
    Assignee: Infinera Corporation
    Inventors: Abdullah S. Karar, Han Sun, Kuang-Tsan Wu
  • Patent number: 10180588
    Abstract: An electro-optical modulator includes a substrate comprising a first Mach-Zehnder modulator comprising a first waveguide and a second waveguide and a second Mach-Zehnder modulator comprising a first waveguide and a second waveguide. A first positive signal electrode is positioned on the substrate over the first waveguide of the first Mach-Zehnder modulator and a first negative signal electrode is positioned on the substrate over the second waveguide of the first Mach-Zehnder modulator. The first positive signal electrode and the first negative signal electrode are connected to a first differential signal input. A second positive signal electrode is positioned on the substrate over the first waveguide of the second Mach-Zehnder modulator and a second negative signal electrode positioned on the substrate over the second waveguide of the second Mach-Zehnder modulator. The second positive signal electrode and the second negative signal electrode are connected to a second differential signal input.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: January 15, 2019
    Assignee: Finisar Corporation
    Inventors: Robert Lewen, Andrei Kaikkonen, Christopher Daunt, Marek Chacinski
  • Patent number: 10181909
    Abstract: Embodiments of the present invention pertain to optical wireless architecture. More particularly, certain embodiments of the invention pertain to a novel method and apparatus to generate millimeter-wave signals with simple and/or low cost architecture. Simple millimeter-wave generation and dispersion-tolerant transmission is based on photonic mixing of two free-running lightwaves and self-mixing down-conversion. More particularly, heterodyne mixing of two free run lightwaves is achieved, wherein one lightwave is modulated by an external modulator driven by electrical data as one of the side-bands of a millimeter-wave signal. Optical to electrical conversion is performed and the millimeter-wave signal is broadcasted by a high-frequency antenna to a receiving side having a local oscillator with self-mixing architecture to down-convert the radio frequency to its baseband form.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: January 15, 2019
    Assignees: ZTE CORPORATION (CHINA), ZTE (USA) Inc.
    Inventor: Jianjun Yu
  • Patent number: 10103812
    Abstract: A satellite communication system may include a communication satellite orbiting Earth, a user terminal in radio communication with the communication satellite through a user link, a communication relay apparatus operating at an altitude of approximately 65,000 feet and in optical communication with the communication satellite through a feeder link, and a gateway station in radio communication with the communication relay apparatus through a gateway link.
    Type: Grant
    Filed: January 27, 2016
    Date of Patent: October 16, 2018
    Assignee: The Boeing Company
    Inventors: Greg Busche, John M. Sullivan, Lindsay E. Krejcarek, Jeffrey M. Jesiolowski, Ying J. Feria, David A. Whelan
  • Patent number: 10084545
    Abstract: A distributed traveling-wave Mach-Zehnder modulator driver having a plurality of modulation stages that operate cooperatively (in-phase) to provide a signal suitable for use in a 100 Gb/s optical fiber transmitter at power levels that are compatible with conventional semiconductor devices and conventional semiconductor processing is described.
    Type: Grant
    Filed: December 4, 2017
    Date of Patent: September 25, 2018
    Assignee: Elenion Technologies, LLC
    Inventors: Ran Ding, Thomas Wetteland Baehr-Jones, Michael J. Hochberg, Alexander Rylyakov
  • Patent number: 9916038
    Abstract: A touch sensor includes a touch panel including driving lines and sensing lines and having node capacitors between neighboring or overlapping driving lines and sensing lines, a driving unit configured to modulate driving signals using a direct sequence spread spectrum technique or scheme and simultaneously drive two or more of the driving lines using the modulated driving signals, and a sensing unit configured to demodulate the signals from the sensing lines using the direct sequence spread spectrum method and generate demodulated signals.
    Type: Grant
    Filed: November 19, 2015
    Date of Patent: March 13, 2018
    Assignee: Dongbu HiTek Co. Ltd.
    Inventor: Hak Soo Kim
  • Patent number: 9897894
    Abstract: Systems and methods of performing logical operations with photonic quantum logic gates. The logic gates utilize photon states, usually orthogonal linearly polarized states, to selectively enact self-interference operations whose outputs can be altered by inducing phase shifts in one or more portions of the section of the logic gate where the photon states undergo self-interference. The polarization direction switchings are differentially enacted and/or not enacted, in groupings of switches, to perform various logic operations. Additionally, networked logic gates with interrelated self-interference section phase shifts and output states are described that provide additional capabilities.
    Type: Grant
    Filed: January 7, 2013
    Date of Patent: February 20, 2018
    Inventor: Daniel S Klotzer
  • Patent number: 9843390
    Abstract: An apparatus comprising a digital signal processor (DSP) unit configured to perform fiber dispersion pre-compensation on a digital signal sequence based on a dispersion value to produce a pre-compensated signal, wherein the dispersion value is associated with a remote optical receiver, a plurality of digital-to-analog converters (DACs) coupled to the DSP unit and configured to convert the pre-compensated signal into analog electrical signals, and a frontend coupled to the DACs and configured to convert the analog electrical signals into a first optical signal, adding a constant optical electric (E)-field to the first optical signal to produce a second optical signal, and transmit the second optical signal to the remote optical receiver.
    Type: Grant
    Filed: February 3, 2017
    Date of Patent: December 12, 2017
    Assignee: Futurewei Technologies, Inc.
    Inventors: Xiang Liu, Frank Effenberger
  • Patent number: 9735884
    Abstract: An optical transmitter includes: optical modulation means; bias voltage output means for supplying the optical modulation means with a bias voltage on which a pilot signal is superimposed; pilot signal receiving means; and bias voltage control means. The bias voltage control means includes: training means for determining a control start voltage and a control direction of the bias voltage based on a pilot signal component at first and second bias voltage values; and feedback means for determining an appropriate bias voltage to compensate for a deviation of an operating point of the optical modulation means by analyzing the pilot signal component while adjusting the bias voltage in a stepwise fashion along the control direction from the control start voltage after the control start voltage and the control direction are determined.
    Type: Grant
    Filed: August 21, 2013
    Date of Patent: August 15, 2017
    Assignee: NEC Corporation
    Inventor: Yuta Goebuchi
  • Patent number: 9729244
    Abstract: A transmitter with at least one optical modulator adapted to modulate the optical signal output by a laser source to generate a modulated optical signal, wherein the optical signal output by the laser source is tapped and supplied to a monitoring circuit comprising an optical front end configured to select signal components of the tapped modulated optical signal and to convert the selected signal components of the tapped modulated optical signal into analog signals, and comprising at least one analog-to-digital converter, ADC, adapted to perform equivalent-time sampling of the analog signals to provide digital signals processed by a processing unit to monitor signal quality of the modulated optical signal.
    Type: Grant
    Filed: October 20, 2014
    Date of Patent: August 8, 2017
    Assignee: ADVA Optical Networking SE
    Inventors: Mohammad Alfiad, Sorin Tibuleac
  • Patent number: 9641257
    Abstract: An optical transmitter for modulating light from a light source to generate an optical transmission signal with use of a data sequence as an electric signal, the optical transmitter including: a mapping section for mapping the data sequence to be converted into multi-level data based on modulation multi-level degree information indicating multi-level degree of the modulation; a D/A converter for converting the multi-level data output from the mapping section into an analog signal; an optical modulator to be driven based on the analog signal output from the D/A converter, for modulating the light from the light source; and a bias control section for setting control polarity of DC bias control of the optical modulator based on the modulation multi-level degree information.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: May 2, 2017
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takashi Sugihara, Tsuyoshi Yoshida
  • Patent number: 9544060
    Abstract: Since it is difficult to control correctly and optimally the DC biases of an IQ modulator driven with pre-equalized data, a method for controlling an optical transmitter according to an exemplary aspect of the invention includes the steps of (a) making direct current biases for driving children Mach-Zehnder modulators of an IQ modulator in the optical transmitter converge to values close to null driving points of the children Mach-Zehnder modulators, (b) driving the children Mach-Zehnder modulators with special driving data including a pair of training patterns between which there is a significant correlation, (c) scanning direct current biases for setting quadrature angle of the IQ modulator, (d) monitoring output of the IQ modulator during step (c), and (e) setting the direct current bias for setting quadrature angle on the basis of the driving data and monitored results in step (d).
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: January 10, 2017
    Assignee: NEC CORPORATION
    Inventor: Emmanuel Le Taillandier De Gabory
  • Patent number: 9438352
    Abstract: The present invention discloses a QPSK signal conjugate relationship identification method and apparatus. The method includes: receiving a first binary sequence signal, using the first binary sequence signal to modulate an optical signal, and determining, within a first predetermined range, a first bias voltage in a QPSK modulator; receiving a second binary sequence signal, using the second binary sequence signal to modulate the optical signal, determining a second range within the first predetermined range according to the first bias voltage, and determining, within the second range, a second bias voltage in the QPSK modulator; and determining a conjugate relationship of the QPSK signal according to a value relationship between the first bias voltage and the second bias voltage. The present invention features low costs and a small component size.
    Type: Grant
    Filed: September 10, 2014
    Date of Patent: September 6, 2016
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Jiahong Zeng
  • Patent number: 9270379
    Abstract: Disclosed are structures and methods for generating a Nyquist superchannel.
    Type: Grant
    Filed: March 18, 2014
    Date of Patent: February 23, 2016
    Assignee: NEC Laboratories America, Inc.
    Inventors: Yue-Kai Huang, Shaoliang Zhang, Fatih Yaman, Dayou Qian
  • Patent number: 9203517
    Abstract: Embodiments of the present disclosure relate to a signal transmission method The signal receiving method includes: receiving a first transmit signal, where the first transmit signal includes a first polarized optical signal and a second polarized optical signal that are perpendicular to each other, where the first polarized optical signal is loaded with first data, the first transmit signal is an uplink signal, and the first data is uplink data, or, the first transmit signal is a downlink signal, and the first data is downlink data; splitting the first transmit signal into a first signal and a second signal according to power; separately rotating a first polarized optical signal and a second polarized optical signal of the second signal by 90 degrees; and performing coherent mixing on the rotated second signal and the first signal to obtain the first data.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: December 1, 2015
    Assignees: Hong Kong Polytechnic University, Huawei Technologies Co., Ltd.
    Inventors: Lei Zhou, Guo Wei, Chao Lv, Dawei Wang, Botao Liu
  • Patent number: 9104084
    Abstract: There is described an optical modulation system for transmitting modulated optical light. The system comprises an electro-optic modulator having at least two arms through which light is transmitted and an imbalance electrode located on at least one arm. A current source is configured to inject current into the imbalance electrode for modifying the phase of light passing through the arm. A dither generator is configured to modulate the injected current, or bias voltage applied to at least one of the arms, with a dither signal. A phase sensitive detector is configured to detect an error in the phase of light emitted by the modulator. An operating point controller is configured to monitor the detected phase error and adjust the current injected into the imbalance arm so as to compensate for the detected error and thereby control an operating point of the modulator.
    Type: Grant
    Filed: July 17, 2012
    Date of Patent: August 11, 2015
    Assignee: Oclaro Technology Limited
    Inventors: Alan Tipper, Amyas Holroyd
  • Patent number: 9094129
    Abstract: A transmitter module includes a processor configured to receive input data, and determine input values corresponding to the input data; a digital-to-analog converter configured to receive the input values from the processor, and generate first and second voltage signals based on the input values; a laser configured to output light; a Mach-Zehnder modulator configured to receive the light from the laser and the first and second voltage signals from the digital-to-analog converter, and modulate the light based on the first and second voltage signals to generate a modulated optical signal that includes distortion; and a filter configured to receive the modulated optical signal from the modulator, process the modulated optical signal to reduce or eliminate the distortion and produce an output optical signal, and output the output optical signal.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: July 28, 2015
    Assignee: Infinera Corporation
    Inventor: David James Krause
  • Patent number: 9042685
    Abstract: This invention concerns real-time multi-impairment signal performance monitoring. In particular it concerns an optical device, for instance a monolithic integrated photonics chip, comprising a waveguide having an input region to receive a signal for characterization, and a narrow band CW laser signal. A non-linear waveguide region to mix the two received signals. More than one output region, each equipped with bandpass filters that extract respective discrete frequency bands of the RF spectrum of the mixed signals. And, also comprising (slow) power detectors to output the extracted discrete frequency banded signals.
    Type: Grant
    Filed: June 20, 2011
    Date of Patent: May 26, 2015
    Assignee: The University of Sydney
    Inventors: Trung Duc Vo, William Peter Corcoran, Mark David Pelusi, David James Moss, Benjamin John Eggleton, Jochen Bernhard Schroeder
  • Publication number: 20150132014
    Abstract: The present invention discloses a QPSK signal conjugate relationship identification method and apparatus. The method includes: receiving a first binary sequence signal, using the first binary sequence signal to modulate an optical signal, and determining, within a first predetermined range, a first bias voltage in a QPSK modulator; receiving a second binary sequence signal, using the second binary sequence signal to modulate the optical signal, determining a second range within the first predetermined range according to the first bias voltage, and determining, within the second range, a second bias voltage in the QPSK modulator; and determining a conjugate relationship of the QPSK signal according to a value relationship between the first bias voltage and the second bias voltage. The present invention features low costs and a small component size.
    Type: Application
    Filed: September 10, 2014
    Publication date: May 14, 2015
    Inventor: Jiahong Zeng
  • Patent number: 9020361
    Abstract: An optical signal transmitter of the present invention includes: two phase modulating portions; a phase shifter which displaces carrier phases of two output lights from the phase modulating portions by ?/2; a multiplexing portion which multiplexes two signal lights, carrier phases of the two signal lights being made orthogonal to each other by the phase shifter; a drive signal electrode portion which supplies a differential data signal to each of four paths of interference optical waveguides, each of the two phase modulating portions having the interference optical waveguides, the differential data signal having an amplitude which is equal to a half-wave voltage V? of the two phase modulating portions; a drive amplifier which amplifies the differential data signal to be supplied to each of the four paths of the interference optical waveguides; a data bias electrode portion which supplies a total of four data bias voltages to two arms, each of the two phase modulating portions having the two arms; an orthogona
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: April 28, 2015
    Assignees: Nippon Telegraph and Telephone Corporation, NTT Electronics Corporation
    Inventors: Hiroto Kawakami, Eiji Yoshida, Masahiro Tachibana
  • Patent number: 9020363
    Abstract: After a startup of an optical transmitter, a control is started in such a way that a modulation amplitude of a driving signal of a phase modulator is set as 0, and that an operational point of a bias voltage is set as the lowest point of light transmission characteristics of the phase modulator. When the operational point of the bias voltage reaches the lowest point, the modulation amplitude of the driving signal is gradually increased from 0 to 2V?.
    Type: Grant
    Filed: October 26, 2012
    Date of Patent: April 28, 2015
    Assignee: Fujitsu Optical Components Limited
    Inventor: Shuichi Yasuda
  • Publication number: 20150104195
    Abstract: Provided is a working point controlling device and method for applying MZ modulator, which includes: a light modulator; a transimpedance amplifier, transmits current outputted by PD of the modulator into voltage signal; a low-noise amplifier, detects low-frequency signal and amplifies the signal, in order to improve the signal/noise ratio; a high Q band-pass filter, detects error signal and amplifies the signal, in order to improve the signal/noise ratio; a first power level conditioning, performs power level condition on error signal of phase, in order that signal output meets A/D input rang; a micro processor, generates low-frequency signal and finishes software synchronization detection wave and ratio integration PI adjusting algorithm; a second power level conditioning, finishes D/A output voltage condition, in order that D/A output is able to meet direct current offset whole controlling range power voltage range of the light modulator.
    Type: Application
    Filed: May 22, 2013
    Publication date: April 16, 2015
    Applicant: Wuhan Telecommunication Devices Co., Ltd.
    Inventors: Yi Hu, Liang Cai, Hui Zou, Jin Yang, Yang Kuang
  • Publication number: 20150104194
    Abstract: Phase shift keying optical modulation apparatus comprising optical phase shifting apparatus and an optical modulator. The optical phase shifting apparatus is arranged to receive an optical carrier signal and is arranged to selectively apply a preselected optical phase shift to the optical carrier signal in dependence on a symbol of a 2N-level phase shift keying modulation format to be encoded onto the optical signal. The optical modulator is arranged to receive the optical carrier signal from the optical phase shifting apparatus and is arranged to apply a phase modulation to the optical carrier signal in dependence on the symbol, to thereby encode the symbol onto the optical carrier signal. The phase modulation is a phase-modulation of an N-level phase shift keying modulation format.
    Type: Application
    Filed: March 19, 2012
    Publication date: April 16, 2015
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventor: Antonio D'Errico
  • Patent number: 9002145
    Abstract: The optical frequency comb generating device having two optical modulation parts 41 and 42 independently modulating optical waves propagating in two branch waveguides and a phase regulator 43 controlling a phase difference between the optical waves includes amplitude adjusting means 22 for adjusting a voltage amplitude of the RF signal supplied to at least one of the optical modulation parts, monitoring means 21 for monitoring the intensity Pout of the output light beam, and a bias control circuit 20 that controls the amplitude adjusting means to change a difference in voltage amplitude between the RF signals supplied to each optical modulation part, that detects a variation of the output light beam corresponding to the variation of the difference in voltage amplitude from the output signal of the monitoring means, and that controls the phase regulator on the basis of the detection result to adjust the phase difference.
    Type: Grant
    Filed: February 21, 2011
    Date of Patent: April 7, 2015
    Assignee: Sumitomo Osaka Cement Co., Ltd.
    Inventors: Masaaki Sudo, Masahito Mure
  • Publication number: 20150093120
    Abstract: It is possible to suppress carrier light with a simple configuration when modulating the carrier light to generate optical sideband components. An optical carrier-suppressed signal generator includes first splitting means used to split input carrier light into two light beams, an optical modulator which modulates one split carrier light beam and outputs light including optical sideband components, a phase modulator which phase-modulates another split carrier light beam, and second or third splitting means used to split the output light of the optical modulator into two light beams. The output light split by the second or third splitting means and the output light of the phase modulator are multiplexed to obtain the amplitude of the signal waveform of optical power, and the optical modulator is controlled such that the obtained value is minimized.
    Type: Application
    Filed: September 28, 2012
    Publication date: April 2, 2015
    Inventors: Takeshi Sakai, Masahito Mure, Junichiro Ichikawa
  • Publication number: 20150093121
    Abstract: An optical semiconductor device includes: an active region which includes an active layer which produces light when current is injected therein, a first diffraction grating layer having a first diffraction grating with a prescribed grating period, and a phase shift portion formed within the first diffraction grating layer, wherein the phase shift portion provides a phase shift not smaller than 1.5? but not larger than 1.83?; and a distributed reflection mirror region which is optically coupled to a first end of the active region as viewed along a direction of an optical axis, and which includes a second diffraction grating which reflects the light produced by the active region back into the active region.
    Type: Application
    Filed: September 15, 2014
    Publication date: April 2, 2015
    Applicant: FUJITSU LIMITED
    Inventors: Manabu Matsuda, Ayahito Uetake
  • Patent number: 8995844
    Abstract: An optical homodyne communication system and method in which a side carrier is transmitted along with data bands in an optical data signal, and upon reception, the side carrier is boosted, shifted to the center of the data bands, and its polarization state is matched to the polarization state of the respective data bands to compensate for polarization mode dispersion during transmission. By shifting a boosted side carrier to the center of the data bands, and by simultaneously compensating for the effects of polarization mode dispersion, the provided system and method simulate the advantages of homodyne reception using a local oscillator. The deleterious effects of chromatic dispersion on the data signals within the data bands are also compensated for by applying a corrective function to the data signals which precisely counteracts the effects of chromatic dispersion.
    Type: Grant
    Filed: April 17, 2014
    Date of Patent: March 31, 2015
    Assignee: Teradvance Communications LLC
    Inventors: Marcel F. C. Schemmann, Zoran Maricevic, Antonije R. Djordjevic, Darby Racey
  • Publication number: 20150086217
    Abstract: A method for increasing energy in a pulse optical beam is provided. The method may include: receiving an optical input beam having a period pulse train with a given repetition frequency; splitting the input beam into N optical signals; phase modulating each signal in the N optical signals at a different phase, such that the N optical signal are orthogonal to each other; and coherently combining each of the phase modulated signals into a single optical output beam.
    Type: Application
    Filed: June 11, 2013
    Publication date: March 26, 2015
    Inventor: Almantas Galvanauskas
  • Patent number: 8989600
    Abstract: A modulating apparatus includes a branch that branches input light; a first modulating unit that modulates the phase of a first branch obtained by the branch; a second modulating unit that modulates a second branch obtained by the branch; a third modulating unit that is connected in series to the first modulating unit, transmits the first branch without branching the first branch, modulates the phase of light transmitted by controlling a refractive index of the light transmitted; a fourth modulating unit that is connected in series to the second modulating unit, transmits the second branch without branching the second branch, and modulates the phase of a light transmitted by controlling a refractive index of the light transmitted; and a coupler that couples the first branch modulated by the first and the third modulating units and the second branch modulated by the second and the fourth modulating units, at different intensities.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: March 24, 2015
    Assignee: Fujitsu Optical Components Limited
    Inventor: Kenichi Nakamoto
  • Patent number: 8983305
    Abstract: The present invention provides a method and an apparatus for controlling a phase delay offset point of a modulator. The method comprises: acquiring backlight detection current signals output from a modulator in different working states, and determining harmonic amplitude values of the backlight detection current signals corresponding to the different working states; determining a detection value of a phase delay offset point corresponding to the modulator according to the determined harmonic amplitude values; comparing the detection value with a set target value of the phase delay offset point, and controlling a position of the phase delay offset point corresponding to the modulator according to the comparison result. The accuracy of controlling the position of the phase delay offset point of the modulator and the performance of the Differential Quadrature Phase Shift Keying (DQPSK) modulation system are improved through the technical solution.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: March 17, 2015
    Assignee: ZTE Corporation
    Inventors: Hong Yi, Jianhong Chen
  • Patent number: 8977119
    Abstract: The embodiments provide an automatic bias control method and apparatus for an optical transmitter. The apparatus includes: a detecting unit configured to monitor output optical power of an I/Q modulator of the optical transmitter; a calculating unit configured to calculate bias voltage indicating values of the I modulator, Q modulator and phase modulator of the I/Q modulator according to the output optical power and known modulation data; and an adjusting unit configured to adjust respectively Direct-Current (DC) bias voltages of the I modulator, Q modulator and phase modulator according to the bias voltage indicating values of the I modulator, Q modulator and phase modulator. With the embodiments, known modulation data are used to realize automatic bias control by monitoring the evenness of distribution of the power of output optical signals of the transmitter in the four quadrants of an I/Q plane.
    Type: Grant
    Filed: July 3, 2013
    Date of Patent: March 10, 2015
    Assignee: Fuijtsu Limited
    Inventors: Meng Yan, Zhenning Tao
  • Publication number: 20150063819
    Abstract: The present invention provides an optical transmitter, an optical transmission/reception system, and a drive circuit, which are capable of adjusting linearity of signal intensity of output light. The optical transmitter includes an optical transmission lines through which an optical signal propagates, phase modulation regions being formed on the optical transmission line. A decoder decodes an input digital signal and outputs signals according to a decoded value. A drive circuit outputs drive signals level of which is equal to or more than three to the each of the plurality of phase modulation regions based on the signals. A control circuit adjusts full-scale amplitude of each of the drive signals by controlling the drive circuit.
    Type: Application
    Filed: November 6, 2012
    Publication date: March 5, 2015
    Inventor: Hidemi Noguchi
  • Publication number: 20150063822
    Abstract: An optical modulator includes optical waveguides on which phase modulation regions are formed. A drive circuit includes a lower-bit drive unit, an upper-bit drive unit, and a bit splitting unit. The bit splitting unit splits an input digital signal into upper bits and lower bits. The lower-bit drive unit outputs a value obtained by performing D/A conversion on the lower bits to phase modulation regions. The upper-bit drive unit outputs, to phase modulation regions, a value greater than a maximum value of values output from the lower-bit drive unit, or a minimum value of the values output from the lower-bit drive unit, according to a value of the upper bits.
    Type: Application
    Filed: November 6, 2012
    Publication date: March 5, 2015
    Inventor: Hidemi Noguchi
  • Publication number: 20150063827
    Abstract: Method for modulating a carrier light wave to achieve, a modulated light wave which carries information by symbols selected from a set of at least two different symbols. The light led through each path is phase-shifted by a respective total variable part phase shift, which for each path is the sum of at least three respective variable part phase shifts. Each variable part phase shift for each modulation state assumes one of two respective predetermined values, and each symbol is modulated using a respective combination of two such total variable part phase shifts. The modulation performed by the two paths is a PSK (Phase Shift Keying) modulation scheme, the group of symbols includes 2N unique symbols, the light led through each respective path is phase shifted using 2N?1 variable part phase shifts, and the respective difference between the respective predetermined values is the same for all variable part phase shifts.
    Type: Application
    Filed: September 4, 2013
    Publication date: March 5, 2015
    Applicant: FINISAR SWEDEN AB
    Inventors: Christopher DAUNT, Peter SZABO, Jan-Olof WESSTROM, Urban ERIKSSON
  • Patent number: 8965211
    Abstract: A system and method of digitizing an analog signal without an amplitude channel is disclosed. The system and method includes receiving an analog signal comprising a voltage v(t) and a frequency f1, producing a series of optical pulses at a sampling frequency f2 with a pulsed laser, splitting the series of optical pulses into a first optical signal and an optical reference signal, phase modulating the first optical signal with the analog signal to produce a sampled optical signal such that phase shifts between adjacent samples in the sampled optical signal does not exceed ? radians, and receiving the sampled optical signal and the optical reference signal at a photonic signal processor.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: February 24, 2015
    Assignee: Rockwell Collins, Inc.
    Inventors: Raymond Zanoni, Kim S. Jepsen, Oliver S. King, Mark A. Laliberte
  • Publication number: 20150043918
    Abstract: The methods, systems, and apparatuses described in this disclosure enable the use of pluggable optics such that two outgoing connections or two incoming connections can support the use of dual transmitter optics and/or dual receiver optics. The forward and/or reverse capacity of an optical network can be doubled using two transmitters and/or receivers operating in parallel. In embodiments, forward and/or reverse capacity of an optical network can be doubled using a double capacity transmitter or receiver that is operable to combine two or more electrical signals into a single optical signal. A pluggable can support two transmitting or two receiving optical links, and can also support a double capacity transmitting or receiving optical link.
    Type: Application
    Filed: August 11, 2014
    Publication date: February 12, 2015
    Inventors: Zoran Maricevic, Venkatesh G. Mutalik, Marcel F. Schemmann
  • Patent number: 8953950
    Abstract: A ultra high speed photonic Analog to Digital Converted (ADC) for sampling and quantizing an electrical voltage signal, internally enabled by photonics uses coherent optical detection architectures for photonic quantization. Coherent light is phase modulated by the test signal. Using an interferometer, or an array of interferometers the phase of modulated light is compared with a reference light. Flash ADC, successive approximation ADC and delta-sigma ADC configurations are presented.
    Type: Grant
    Filed: July 25, 2010
    Date of Patent: February 10, 2015
    Assignee: Technion Research and Development Foundation Ltd.
    Inventors: Moshe Nazarathy, Igor Zelniker
  • Patent number: 8947766
    Abstract: An optical device comprising a tunable optical frequency comb generator. The comb generator includes an interferometer, and an optical feed-back loop waveguide.
    Type: Grant
    Filed: May 5, 2014
    Date of Patent: February 3, 2015
    Assignee: Alcatel Lucent
    Inventors: Long L. Chen, Christopher R. Doerr, Nicolas Dupuis
  • Patent number: 8948609
    Abstract: According to a first aspect, techniques are provided to optimize a Mach-Zehnder modulator drive waveform by distorting the outer modulation levels of the waveform, thereby equalizing eye openings of the received optical field, and in particular creating a wider and more defined central eye opening of the received optical field. According to a second aspect, techniques are provided to adjust in-phase (I) modulation levels based on the imperfect performance of a Mach-Zehnder modulator allocated to modulate quadrature-phase (Q) modulation levels, and conversely to adjust the Q modulation levels based on the imperfect performance of an MZ modulator allocated to modulate I modulation levels.
    Type: Grant
    Filed: February 24, 2012
    Date of Patent: February 3, 2015
    Assignee: Cisco Technology, Inc.
    Inventors: James Whiteaway, Thomas Duthel, Jonas Geyer
  • Patent number: 8948299
    Abstract: A communication device includes: a converting part converting a data signal from a non-return-to-zero signal to a return-to-zero signal; a trigger flip-flop inverting an output signal every time the return-to-zero signal changes in one cycle; a first filter outputting a positive pulse and a negative pulse alternately, which indicate existence and absence of the pulse corresponding to a value of the data signal, by removing a low frequency component of an output signal of the trigger flip-flop.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: February 3, 2015
    Assignee: Fujitsu Limited
    Inventors: Yasuhiro Nakasha, Hiroki Hayashi, Takumi Itoh
  • 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: 8934633
    Abstract: High-security communications against information leakage as well as high-speed communications are realized using present optical fiber networks. The methods are as follows: (1) A seed key is shared between a transmitter and a receiver in advance. Random numbers are transmitted using carrier light accompanied by fluctuations and bases that are decided by random numbers. The transmitter and receiver compare a shared basis that is determined by the seed key with the random basis, and decompose the random numbers superimposed on each bit into two sequences, based on whether the shared basis coincides with the random basis or not. Error correction is processed for each sequence in the receiver, and then the random numbers are shared between the transmitter and the receiver. (2) The amount of the random numbers shared between the transmitter and the receiver is reduced to secret capacity through privacy amplification, and the resultant random numbers are used as a secret key.
    Type: Grant
    Filed: January 17, 2011
    Date of Patent: January 13, 2015
    Assignee: Hitachi, Ltd.
    Inventor: Tatsuya Tomaru
  • Patent number: 8929745
    Abstract: A first clock modulator branches a light beam, varies a phase difference of the resulting light beams according to a first clock, and causes interference of the light beams. A second clock modulator branches a light beam from the first clock modulator and synchronized with the first clock, varies a phase difference of the resulting light beams according to a second clock, and causes interference of the light beams. A third clock modulator branches a light beam from the first clock modulator and inversely synchronized with the first clock, varies a phase difference of the resulting light beams according to a third clock, and causes interference of the light beams. The second clock and the first clock have identical cycles and differing phases. The third clock and the second clock have phases that differ by a 1/2 cycle. Four data modulators modulate the light beams from the clock modulators.
    Type: Grant
    Filed: June 24, 2013
    Date of Patent: January 6, 2015
    Assignee: Fujitsu Optical Components Limited
    Inventor: Toru Yamazaki
  • Publication number: 20140376925
    Abstract: A method modulates data for optical communication by first encoding the data using a forward error correction (FEC) encoder to produce encoded data, which are encoded using a block encoder to produce block encoded data such that Hamming distances between code words that represent the block encoded data are increased. The block encoded data are mapped to produce mapped data such that Euclidian distances between the constellation points are increased. Then, the mapped data are modulated in a transmitter to a modulated signal for an optical channel.
    Type: Application
    Filed: June 19, 2013
    Publication date: December 25, 2014
    Applicant: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Toshiaki Koike-Akino, Andrew Knyazev, David S Millar
  • Patent number: 8917998
    Abstract: A method implemented in a transmission apparatus used in an optical fiber communications system for a polarization switched differential quaternary phase-shift keying (DQPSK) signal is disclosed. The method comprises splitting data into two or more data streams, inputting said two or more data streams to 1-bit DQPSK precoders to perform 1-bit DQPSK precoding, and multiplexing inphase outputs of the 1-bit DQPSK precoders to generate a first output; and multiplexing quadrature outputs of the 1-bit DQPSK precoders to generate a second output. Other methods, apparatuses, and systems also are disclosed.
    Type: Grant
    Filed: October 11, 2012
    Date of Patent: December 23, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Shaoliang Zhang, Lei Xu, Junqiang Hu, Fatih Yaman, Ting Wang, Yoshihisa Inada, Takaaki Ogata, Yasuhiro Aoki
  • Patent number: 8909067
    Abstract: The I phase modulator modulates a phase based on the bias voltage in which a first modulation signal and a first pilot signal are inherent and the Q phase modulator modulates a phase based on the bias voltage in which a second pilot signal different from the first pilot signal and a second modulation signal are inherent. A time-average power synchronous detection unit detects an optical power at a timing at which the positivity and negativity of the voltages of both pilot signals become the same, and an optical power when the positivity and negativity of the voltages of both pilot signals are opposite. The bias voltage control unit controls the bias voltage so that the difference between both the optical powers becomes small based on the detection result of the time-average power synchronous detection unit.
    Type: Grant
    Filed: May 14, 2012
    Date of Patent: December 9, 2014
    Assignee: Oclaro Japan, Inc.
    Inventors: Kouji Takeguchi, Shigehiro Takashima, Taichi Kogure, Hirofumi Nakagawa, Saki Narisawa