Including Compensation Patents (Class 398/192)
  • Patent number: 10305598
    Abstract: A method and apparatus for isolating an RF signal are provided. A first RF signal is received and passed to an input of a 90 degree hybrid. An output of the 90 degree hybrid is connected to a first waveguide and a second output is connected to a second waveguide of an optical modulator. A second RF signal is received and passed to an input of a second 90 degree hybrid. An output of the second 90 degree hybrid is connected to the second waveguide and a second output is connected to the first waveguide of the optical modulator. The optical modulator is biased to produce single side band optical outputs of the RF signals. The single side band optical outputs are passed to an optical notch filter to remove one of the side band outputs. The other of the side band optical outputs is converted to an electrical signal.
    Type: Grant
    Filed: November 25, 2015
    Date of Patent: May 28, 2019
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Preetpaul S Devgan
  • Patent number: 10291346
    Abstract: In an example, a communication module includes an optical transmitter, an optical receiver, and a periodical filter. The optical transmitter is configured to emit an outbound optical signal. The optical receiver is configured to receive an inbound optical signal. A first frequency of the outbound optical signal is offset from a second frequency of the inbound optical signal by an amount less than a channel spacing of a multiplexer/demultiplexer implemented in an optical communication system that includes the communication module. The periodical filter is positioned in optical paths of both the outbound optical signal and the inbound optical signal and has a transmission spectrum with periodic transmission peaks and troughs. The first frequency of the outbound optical signal may be aligned to one of the transmission peaks and the second frequency of the inbound optical signal may be aligned to one of the transmission troughs, or vice versa.
    Type: Grant
    Filed: March 21, 2017
    Date of Patent: May 14, 2019
    Assignee: FINISAR CORPORATION
    Inventors: Leo Yu-Yu Lin, Huade Shu, Huiping Li, Li Zhang, Shanshan Zeng, Guangsheng Li
  • Patent number: 10162139
    Abstract: Semiconductor packages are provided. The semiconductor package includes a package substrate, a photonic integrated circuit, a laser die, an electronic integrated circuit, and a first redistribution structure. The package substrate includes connectors. The photonic integrated circuit is disposed over the package substrate. The laser die is optically coupled to the photonic integrated circuit. The electronic integrated circuit is disposed over the package substrate. The first redistribution structure is disposed over the package substrate, wherein the electronic integrated circuit is electrically connected to the photonic integrated circuit through the first redistribution structure.
    Type: Grant
    Filed: July 27, 2017
    Date of Patent: December 25, 2018
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Chuei-Tang Wang, Jeng-Shien Hsieh, Hsing-Kuo Hsia, Chen-Hua Yu
  • Patent number: 10110978
    Abstract: A data communication system for transmitting packets over one or more optical fibers includes a transponder with a number of digital signal processors that transmit data packets on different optical channels. The transponder includes a switch that receives a data packet on an input and selects one of the digital signal processors to transmit the packet based on quality metrics for the different optical channels and/or information included in an OSI header for the data packet.
    Type: Grant
    Filed: October 28, 2016
    Date of Patent: October 23, 2018
    Assignee: Facebook, Inc.
    Inventors: Ilya Lyubomirsky, Hans-Juergen Schmidtke, Michael Louis Bortz
  • Patent number: 9712248
    Abstract: An optical transmission device includes: an optical splitter configured to branch signal light input from a first optical network; a variable optical attenuator configured to control an attenuation amount of first branched signal light branched by the optical splitter and output the first branched signal light for a second optical network; and a controller configured to detect a modulation component of a signal superimposed on the signal light from second branched signal light branched by the optical splitter and control, based on the detected modulation component, an attenuation amount of the variable optical attenuator, so that the modulation component is suppressed.
    Type: Grant
    Filed: March 17, 2015
    Date of Patent: July 18, 2017
    Assignee: FUJITSU LIMITED
    Inventor: Tomoaki Watanabe
  • Patent number: 9450378
    Abstract: The method for controlling a wavelength-tunable laser comprises a first step of acquiring a driving condition of the wavelength-tunable laser for laser oscillation at a first wavelength, and a second step of calculating according to the driving condition of the first wavelength and a wavelength difference between the first wavelength and a second wavelength different from the first wavelength a control value or target value of a wavelength characteristic of the second wavelength in the wavelength detection unit, so as to calculate a driving condition for driving the wavelength-tunable laser, the second step including a step of selecting according to the wavelength difference one of etalon slopes having respective gradients identical and opposite to a gradient of an etalon slope used for controlling the first wavelength.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: September 20, 2016
    Assignee: Sumitomo Electric Device Innovations, Inc.
    Inventors: Hirokazu Tanaka, Masao Shibata, Mitsuyoshi Miyata
  • Patent number: 9294195
    Abstract: Embodiments of the present invention disclose a method, a device, and a system for saving energy in optical communication. The method includes the following: sending first information to an optical communication device at a peer end through the optical module by using a first transmit optical power; receiving, through the optical module, second information that is returned by the optical communication device at the peer end after it receives the first information; and reducing, according to the first transmit optical power, and a receive optical power value and minimum receive optical power value in the received second information, the transmit optical power value of the optical module of the optical communication device to a difference value between the first transmit optical power value and the receive optical power value plus the minimum receive optical power value of the optical communication device at the peer end and a margin value.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: March 22, 2016
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Qingyin Fang
  • Patent number: 9246599
    Abstract: In a coherent optical receiver, sufficient demodulation becomes impossible and consequently receiving performance deteriorates if an interchannel skew arises, therefore, a coherent optical receiver according to an exemplary aspect of the invention includes a local light source; a 90-degree hybrid circuit; an optoelectronic converter; an analog-to-digital converter; and a digital signal processing unit, wherein the 90-degree hybrid circuit makes multiplexed signal light interfere with local light from the local light source, and outputs a plurality of optical signals separated into a plurality of signal components; the optoelectronic converter detects the optical signals and outputs detected electrical signals; the analog-to-digital converter quantizes the detected electrical signals and outputs quantized signals; and the digital signal processing unit includes a skew compensation unit for compensating a difference in propagation delay between the plurality of signal components, and a demodulation unit for dem
    Type: Grant
    Filed: November 13, 2013
    Date of Patent: January 26, 2016
    Assignee: NEC CORPORAITON
    Inventors: Wakako Yasuda, Junichi Abe, Kiyoshi Fukuchi
  • Patent number: 9240842
    Abstract: A method and apparatus for isolating an RF signal are provided. A first RF signal is received and passed to an input of a 90 degree hybrid. An output of the 90 degree hybrid is connected to a first waveguide and a second output is connected to a second waveguide of an optical modulator. A second RF signal is received and passed to an input of a second 90 degree hybrid. An output of the second 90 degree hybrid is connected to the second waveguide and a second output is connected to the first waveguide of the optical modulator. The optical modulator is biased to produce single side band optical outputs of the RF signals. The single side band optical outputs are passed to an optical notch filter to remove one of the side band outputs. The other of the side band optical outputs is converted to an electrical signal.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: January 19, 2016
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Preetpaul S Devgan
  • Patent number: 9148221
    Abstract: A system for optical communication through a structure includes a light pipe extending from one side of the structure to another. A sensor in communication with one side of the structure is capable of producing a sensor signal responsive to an environmental condition. Transmitter electronics are joined to the sensor for producing an electrical signal. A light source is joined to the transmitter electronics and to the light pipe to provide an optical signal. An optical detector receives the optical signal from the light pipe on the other side of the structure. Receiver electronics are joined to the optical detector and provide an output signal.
    Type: Grant
    Filed: November 25, 2013
    Date of Patent: September 29, 2015
    Inventors: George M. Duarte, Javier A. Rinaldi, Jonathan S. Preston
  • Patent number: 9112604
    Abstract: There is provided a method for determining an in-band noise parameter, such as the Optical Signal-to-Noise Ratio (OSNR), on an optical signal-under-test (SUT) propagating along an optical communication link and comprising a data-carrying signal contribution of any arbitrary degree of polarization and a noise contribution. A spectral shape trace of data-carrying signal contribution in the SUT is estimated using a reference optical spectrum trace of a reference signal which comprises a data-carrying signal contribution that is spectrally representative of the data-carrying signal contribution of the SUT and a noise contribution which is at least approximately known. The data-carrying signal contribution is mathematically discriminated from said noise contribution in the SUT using the spectral shape trace and the test optical spectrum trace. The in-band noise parameter is then determined at least from the mathematically discriminated noise contribution.
    Type: Grant
    Filed: February 14, 2011
    Date of Patent: August 18, 2015
    Assignee: EXFO INC.
    Inventors: Daniel Gariepy, Gang He
  • Patent number: 9088127
    Abstract: A multisection quantum dot laser (7) comprising at least first (8) and second (9) sections, each section (8, 9) comprising a semiconductor substrate (2) comprising p (3) and n type (4) layers and a quantum dot layer sandwiched therebetween; the semiconductor substrate (2) comprising a back electrical contact in electrical contact with one of the p and n type layers and a tuning electrical contact (13, 14) in electrical contact with the other of the p and n type layers; the quantum-dot layers of the first (10) and second (11) sections being portions of the same quantum dot layer (12) forming a laser cavity.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: July 21, 2015
    Assignee: Finisar UK Limited
    Inventors: Richard Andrew Hogg, David Timothy Dylan Childs, Benjamin James Stevens, Kristian Michael Groom
  • Patent number: 9037003
    Abstract: A signal transmission device drives a light-emitting element and outputs an optical signal depending on a data signal from an electronic device. The device includes an element driving portion which supplies a driving current to the light-emitting element, wherein the driving current is obtained by superimposing a modulation current on a bias current, the modulation current being dependent on the data signal indicating emitting information of the light-emitting element. A temperature compensation portion of the device controls the bias current and the modulation current depending on the temperature so that a temperature-current characteristic of the light-emitting element is reproduced based on the voltage which is dependent on the temperature and the voltage which is independent from the temperature, thereby performing current control depending on the temperature.
    Type: Grant
    Filed: March 26, 2013
    Date of Patent: May 19, 2015
    Assignee: YAZAKI CORPORATION
    Inventors: Chiemi Yamagata, Atsushi Nakata, Kengo Noguchi, Yukio Akazawa
  • Patent number: 9031403
    Abstract: A method includes sweeping an optical frequency of an optical signal by an optical transmitter controlling an electric-field information signal corresponding to a transmitted signal, providing different polarization states for individual frequencies of the optical signal by the optical transmitter controlling a mixture of a first electric-field information signal corresponding to a first transmitted signal and a second electric-field information signal corresponding to a second transmitted signal, obtaining, for individual frequencies of the optical signal, polarization dependent characteristics corresponding to different frequencies, when the optical transmitter sweeps the frequency of the optical signal, by an optical receiver calculating a polarization-dependent characteristic of an optical transmission line between the optical transmitter and the optical receiver, based on items of received-electric-field information corresponding to the different polarization states, and obtaining statistical information
    Type: Grant
    Filed: June 12, 2013
    Date of Patent: May 12, 2015
    Assignee: Fujitsu Limited
    Inventors: Hisao Nakashima, Takeshi Hoshida
  • Patent number: 9020067
    Abstract: Distortion and aliasing reduction for digital to analog conversion. Synthesis of one or more distortion terms made based on a digital signal (e.g., one or more digital codewords) is performed in accordance with digital to analog conversion. The one or more distortion terms may correspond to aliased higher-order harmonics, distortion, nonlinearities, clipping, etc. Such distortion terms may be known a priori, such as based upon particular characteristics of a given device, operational history, etc. Alternatively, such distortion terms may be determined based upon operation of a device and/or based upon an analog signal generated from the analog to conversion process. For example, frequency selective measurements made based on an analog signal generated from the digital to analog conversion may be used for determination of and/or adaptation of the one or more distortion terms. One or more DACs may be employed within various architectures operative to perform digital to analog conversion.
    Type: Grant
    Filed: April 1, 2013
    Date of Patent: April 28, 2015
    Assignee: Broadcom Corporation
    Inventors: Thomas J. Kolze, Bruce J. Currivan, Ramon A. Gomez
  • Patent number: 9020021
    Abstract: An apparatus for encoding data signals includes a transmitter configured to encode and transmit a data signal over a communication channel, the transmitter including a precoder; a signal shaper configured to adjust the data signal by applying an equalization setting to the data signal, the equalization setting including an amplitude and offset and transmit the adjusted data signal to the precoder; and a processing unit. The processing unit is configured to perform: receiving channel coefficients associated with the communication channel; for each of a plurality of amplitude settings and a plurality of offset settings, calculating whether a modulo amplitude level would occur at a receiver using a modulo operation; selecting the equalization setting from the plurality of amplitude settings and the plurality of offset settings based on the calculation; and transmitting a control signal specifying the equalization setting to the signal shaper.
    Type: Grant
    Filed: July 29, 2013
    Date of Patent: April 28, 2015
    Assignee: International Business Machines Corporation
    Inventors: Marcel A. Kossel, Daihyun Lim, Pradeep Thiagarajan
  • 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
  • Patent number: 9014572
    Abstract: An optical transmitter includes an optical modulator having first and second waveguides to modulate carrier light at each of the waveguides using a driving signal with 2*n intensity levels (n is an integer 1 or greater); and a phase shifter to cause a phase difference between a first optical signal and a second optical signal output from the first waveguide and the second waveguide, respectively. A photodetector converts a portion of a multilevel optical modulation signal acquired by combining the first optical signal and the second optical signals into an electrical signal. A monitor detects a change in an alternating current component in the detected modulation signal. A controller controls at least one of a first bias voltage and a second bias voltage being supplied to the first waveguide and the second waveguide, respectively, so as to increase the power value of the alternating current component.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: April 21, 2015
    Assignee: Fujitsu Limited
    Inventor: Yuichi Akiyama
  • Patent number: 9002213
    Abstract: According to a first aspect of the present invention there is provided an apparatus for performing power equalization and phase correction of two signals (400). The apparatus comprises a first hybrid coupler (401) configured to operate as a power combiner, and a second hybrid coupler (402) configured to operate as a power divider, wherein the apparatus is configured to provide an output (406) of the first hybrid coupler as an input (407) to the second hybrid coupler.
    Type: Grant
    Filed: December 2, 2010
    Date of Patent: April 7, 2015
    Assignee: Oclaro Technology Limited
    Inventors: Wenfei Hu, Jonathan Stuart Drake
  • Patent number: 8995828
    Abstract: An optical transmission device includes an extractor that extracts respective optical signals from optical signals multiplexed from a plurality of optical signals of different wavelengths, a detector that detects wavelengths of the extracted respective optical signals, a storage that stores the wavelengths of the detected respective optical signals, and a processor that is operative to derive trends in wavelength variation of the respective optical signals based on the detected respective optical signals and the respective optical signals stored in the storage, and determines that either one or both of the extractor and the detector cause the wavelengths to be varied when the trends in wavelength variation of two or more wavelengths are the same.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: March 31, 2015
    Assignee: Fujitsu Limited
    Inventors: Yuichi Suzuki, Toshihiro Ohtani
  • Patent number: 8989594
    Abstract: A method for adjusting a filtering bandwidth of an optical device includes: acquiring a modulation bandwidth of a first optical signal and s modulation bandwidth of a second optical signal, where the first optical signal is an optical signal input into a first wavelength channel of an optical device, the second optical signal is an optical signal input into a second wavelength channel of the optical device, and the second wavelength channel is adjacent to the first wavelength channel; comparing the modulation bandwidth of the first optical signal with the modulation bandwidth of the second optical signal; and according to a result of comparing the modulation bandwidth of the first optical signal with the modulation bandwidth of the second optical signal, adjusting a filtering bandwidth of at least one wavelength channel of the first wavelength channel and the second wavelength channel.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: March 24, 2015
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Ning Deng
  • Patent number: 8989588
    Abstract: An optical transceiver includes an optical IC coupled to a processor IC. For transmit, the optical IC can be understood as a transmitter IC including a laser device or array. For receive, the optical IC can be understood as a receiver IC including a photodetector/photodiode device or array. For a transmitter IC, the processor IC includes a driver for a laser of the transmitter IC. The driver includes an equalizer that applies high frequency gain to a signal transmitted with the laser device. For a receiver IC, the processor IC includes a front end circuit to interface with a photodetector of the receiver IC. The front end circuit includes an equalizer that applies high frequency gain to a signal received by the receiver IC. The driver can be configurable to receive a laser having either orientation: ground termination or supply termination.
    Type: Grant
    Filed: January 22, 2013
    Date of Patent: March 24, 2015
    Assignee: Intel Corporation
    Inventors: Gil Afriat, Lior Horwitz, Dror Lazar, Assaf Issachar, Alexander Pogrebinsky, Adee O. Ran, Ehud Shoor, Roi Bar, Rushdy A. Saba
  • Publication number: 20150071652
    Abstract: Aspects of the present invention provide techniques for compensating nonlinear impairments of a signal traversing an optical communications system. A parallel array of linear convolutional filters are configured to process a selected set of samples of the signal to generate an estimate of a nonlinear interference field. The predetermined set of samples comprises a first sample and a plurality of second samples. A processor applies the estimated nonlinear interference field to the first sample to least partially compensate the nonlinear impairment.
    Type: Application
    Filed: September 9, 2014
    Publication date: March 12, 2015
    Applicant: CIENA CORPORATION
    Inventors: Qunbi ZHUGE, Shahab OVEIS GHARAN, Michael Andrew REIMER, Maurice O'SULLIVAN
  • Patent number: 8971717
    Abstract: An optical system has an optical emitter that transmits an optical signal through an optical fiber. An optical detector detects light from the fiber and provides an analog signal indicative of such light. A crosstalk cancellation element is configured to receive an electrical signal from the optical emitter and to adjust such signal in order to form a cancellation signal that models the optical and/or electrical crosstalk affecting the analog signal. The cancellation signal is subtracted from the analog signal thereby removing optical and/or electrical crosstalk from the analog signal.
    Type: Grant
    Filed: February 6, 2012
    Date of Patent: March 3, 2015
    Assignee: ADTRAN, Inc.
    Inventor: Daniel M. Joffe
  • Patent number: 8971724
    Abstract: A characteristic compensation method includes obtaining compensation information when degradation of a transmission characteristic of an optical transmission path of a received light signal is compensated for by using digital signal processing with respect to an electric signal obtained by photoelectrically converting the light signal, calculating an compensation value for a characteristic compensation device that optically compensates for degradation of the transmission characteristic to start characteristic compensation, based on the compensation information with respect to the light signal, setting the compensation value in the characteristic compensation device, and switching a state in which compensation is done using the digital signal processing to a state in which compensation is done using the characteristic compensation device after the setting of the compensation value is completed.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: March 3, 2015
    Assignee: Fujitsu Limited
    Inventor: Kiyotoshi Noheji
  • Patent number: 8971719
    Abstract: An optical system may have an optical transmitter including a digital signal processor to receive a signal channel, add data corresponding to a pilot tone, generate a digital signal associated with the signal channel and including the pilot tone, and output the digital signal. The optical system may further have a digital-to-analog converter to convert the digital signal to an analog signal, a laser to provide an optical signal, and a modulator to receive the optical signal and the analog signal, and modulate the optical signal based on the analog signal to form a modulated optical signal. The modulated optical signal may include the pilot tone. The optical system may also have an optical receiver to receive the modulated optical signal, process the modulated optical signal to determine a phase associated with the pilot tone, and apply the phase to the modulated optical signal to recover the signal channel.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: March 3, 2015
    Assignee: Infinera Corporation
    Inventors: Pierre Herve Mertz, David J. Krause, Han Henry Sun
  • 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: 8948604
    Abstract: The present disclosure generally pertains to optical communication apparatuses having field-tunable power characteristics. In one exemplary embodiment, an optical communication apparatus has an optical transmitter. The optical transmitter is coupled to logic that receives a user input indicative of a desired transmit mode for the transmitter, and the logic then dynamically tunes the transmitter's output power according to the selected transmit mode. In addition, the optical communication apparatus may have an optical receiver for receiving optical signals. The sensitivity of the receiver is controlled by a bias voltage that is applied to the receiver by the logic. The logic is configured to receive a user input indicative of a desired receive mode and then to tune the receiver's sensitivity via the bias voltage according to the selected receive mode.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: February 3, 2015
    Assignee: Adtran, Inc.
    Inventors: Leif J. Sandstrom, Phillip Stone Herron
  • Patent number: 8948608
    Abstract: An optical modulator device directly-coupled to a driver circuit device. The optical modulator device can include a transmission line electrically coupled to an internal VDD, a first electrode electrically coupled to the transmission line, a second electrode electrically coupled to the first electrode and the transmission line. A wave guide can be operably coupled to the first and second electrodes, and a driver circuit device can be directly coupled to the transmission line and the first and second electrodes. This optical modulator and the driver circuit device can be configured without back termination.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: February 3, 2015
    Assignee: Inphi Corporation
    Inventor: Carl Pobanz
  • Patent number: 8934779
    Abstract: Methods, architectures, circuits, and/or systems for monitoring operating parameters and/or generating status indications associated with electronic device operation are disclosed. The method can include (i) monitoring a first operating parameter related to operation of the electronic device to determine a first parameter value, (ii) calculating a difference between the first parameter value and a predetermined value for the first operating parameter, (iii) monitoring a second operating parameter on which thresholds for operational warnings and/or alarms are based to determine a second parameter value, (iv) updating or changing the thresholds based on a predetermined change or event in the second parameter value, (v) comparing the difference to the updated or changed thresholds, and (vi) generating a corresponding one of the operational warnings and/or alarms when the difference crosses at least one of the thresholds in a predetermined direction.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: January 13, 2015
    Assignee: Source Photonics, Inc.
    Inventors: Todd Rope, Mark Heimbuch
  • Patent number: 8929746
    Abstract: The present disclosure relates to a differential drive circuit. The differential drive circuit generally includes a differential driver, a first transmission line coupled to a first output node of the differential driver, and a second transmission line coupled to a second output node of the differential driver. A laser diode is coupled to the first and second transmission lines. The first and second transmission lines have different delays, lengths, or impedances. In some embodiments, the delay between the first transmission line and the second transmission line is 0.2-0.4 times a rise time or fall time of a signal on either transmission line.
    Type: Grant
    Filed: December 12, 2011
    Date of Patent: January 6, 2015
    Assignee: Source Photonics, Inc.
    Inventor: Mohammad Azadeh
  • Patent number: 8923706
    Abstract: An optical transmitter configured to perform digital signal equalization directed at mitigating the detrimental effects of a frequency roll-off in the transmitter's optical I-Q modulator. In various embodiments, a frequency-dependent spectral-correction function used for the digital signal equalization can be constructed to cause the spectrum of the modulated optical signal generated by the transmitter to have a desired degree of flatness in the vicinity of an optical carrier frequency and/or to at least partially mirror the frequency roll-off in the optical I-Q modulator.
    Type: Grant
    Filed: July 24, 2012
    Date of Patent: December 30, 2014
    Assignee: Alcatel Lucent
    Inventors: Chandrasekhar Sethumadhavan, Xiang Liu, Peter J. Winzer, Andrew Chraplyvy
  • Publication number: 20140369700
    Abstract: A wavelength tunable laser emission device (1) comprises: a first waveguide (31) comprising an optical amplification means for producing a stimulated light emission, the first waveguide extending in a longitudinal direction of the emission device, a second waveguide (5) made of silicon on silicon dioxide and disposed parallel to the first waveguide spaced from the first waveguide in a vertical direction of the emission device so as to allow the existence of a hybrid optical mode coupled at one and the same time to the second waveguide and to the first waveguide, the second waveguide comprising a distributed reflector (9) along the second waveguide, the second waveguide comprising transverse zones (11, 12, 13, 14) doped differently so as to form a polar junction oriented in a transverse direction of the emission device. Electrodes (15, 16) coupled to the doped transverse zones modify an effective index seen by the hybrid optical mode.
    Type: Application
    Filed: June 4, 2014
    Publication date: December 18, 2014
    Inventors: Hélèn DEBREGEAS-SILLARD, Badhise Ben BAKIR, Guang-Hua DUAN, Nicolas CHIMOT
  • Patent number: 8909064
    Abstract: Aspects of the invention provide transmitters and receivers for managing multiple optical signals. High order modulation, such as phase and/or amplitude modulation, is used to achieve multiple bits per symbol by transporting multiple asynchronous data streams in an optical transport system. One or more supplemental multiplexing techniques such as time division multiplexing, polarization multiplexing and sub-carrier multiplexing may be used in conjunction with the high order modulation processing. This may be done in various combinations to realize a highly spectrally efficient multi-data stream transport mechanism. The system receives a number of asynchronous signals which are unframed and synchronized, and then reframed and tagged prior to the high order modulation. Differential encoding may also be performed. Upon reception of the multiplexed optical signal, the receiver circuitry may employ either direct detection without a local oscillator or coherent detection with a local oscillator.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: December 9, 2014
    Assignee: Google Inc.
    Inventors: Bikash Koley, Vijayanand Vusirikala, Hong Liu
  • Patent number: 8903248
    Abstract: A transmission apparatus includes: a data signal processor to add first data of a control signal to a data signal received, and transmit the data signal; a first signal output module to output second data of the control signal; an update controller to control an update of a function included in the first signal output module; and a second signal output module, when receiving a notice of an instruction for updating the function from the update controller, to output the first data that is the second data held therein when the notice thereof is received, wherein the second signal output module, when receiving a notice of a completion for updating the function from the update controller, outputs the first data that is the second data received from the first signal output module updated by the update controller.
    Type: Grant
    Filed: August 17, 2011
    Date of Patent: December 2, 2014
    Assignee: Fujitsu Limited
    Inventor: Makoto Ohtou
  • Patent number: 8903254
    Abstract: The present disclosure relates to an optical transceiver for use in optical fiber communications and/or telecommunications systems and, more specifically, a low power consumption, long range pluggable transceiver. The transceiver generally comprises a photodiode with a transimpedance amplifier (PIN-TIA); an electro-absorption modulated laser (EML); an optical detector; and a directly modulated laser (DML) driving module connected between the PIN-TIA and EML laser configured to drive the EML laser. A low power-consumption DML driving module is utilized to drive the EML laser, so as to further reduce power consumption. An impedance matching circuit can be applied to modulate an electro-absorption (EA) modulator of the EML laser with maximum efficiency.
    Type: Grant
    Filed: May 24, 2011
    Date of Patent: December 2, 2014
    Assignee: Source Photonics, Inc.
    Inventors: Zhaoyang Hu, Lingqiong Zeng, Thomas Liljeberg
  • Patent number: 8897653
    Abstract: A subscriber-side optical network unit (ONU) includes a control LSI for outputting a data signal and a pre-bias signal at fixed intervals, an optical transmitter-receiver for producing optical output in response to these signals, and a light-emission error preventing circuit for preventing light-emission error. First and second light-emission error detecting circuits output an abnormality detection alarm signal when no rising edge occurs in the data signal and pre-bias signal for a prescribed period of time. An OR element, when receiving the abnormality detection alarm signal from at least one of the first and second light-emission error detecting circuits, supplies the optical transmitter-receiver with a shutdown signal and halts the optical output.
    Type: Grant
    Filed: April 28, 2010
    Date of Patent: November 25, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Senoo, Masaki Noda, Shigeo Yamanaka, Masatoshi Katayama
  • Patent number: 8886050
    Abstract: The present invention provides a wavelength division multiplexing system and a method and device for its residual dispersion compensation, wherein the device for residual dispersion compensation of wavelength division multiplexing system comprises: a performance parameter detecting device for receiving and detecting performance parameter of receiving terminal optical signal and sending detecting result of the performance parameter to a central control device; the central control device for deciding a dispersion regulating mode of a tunable dispersion compensator according to the detecting result of the performance parameter and sending the dispersion regulating mode to a tunable dispersion compensator control device through control signaling; and the tunable dispersion compensator control device for receiving the control signaling sent by the central control device and adjusting dispersion compensation amount of the tunable dispersion compensator according to the control signaling in order to make residual di
    Type: Grant
    Filed: January 10, 2007
    Date of Patent: November 11, 2014
    Assignee: ZTE Corporation
    Inventors: Likun Zhang, Jiaying Wang
  • Patent number: 8886055
    Abstract: An optical communication device (e.g., a transmitter, receiver, or transceiver) includes a control input for selecting between operating the optical communication device in a normal operation mode for communicating data according to a first data rate and operating the optical transmitter in a reduced data rate operation mode for communicating data according to a second data rate lower than the first data rate. The optical communication device includes a forward error correction encoder and/or decoder and a modulator and/or demodulator. When operating in the reduced data rate mode, data is re-formatted for compatibility with the same forward error correction scheme and modulation/demodulation scheme used in the normal data rate mode, thereby enabling the reduced data rate mode without significant architectural overhead.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: November 11, 2014
    Assignee: ClariPhy Communications, Inc.
    Inventor: Damian Alfonso Morero
  • Patent number: 8879925
    Abstract: An optical transmitter includes: a digital signal processor to generate a drive signal from input data; a controller to control an amplitude or power of the drive signal according to information relating to the digital signal processing of the digital signal processor; and an optical modulator to modulate input light with the drive signal controlled by the controller to generate an optical signal.
    Type: Grant
    Filed: December 8, 2011
    Date of Patent: November 4, 2014
    Assignee: Fujitsu Limited
    Inventors: Yuichi Akiyama, Takeshi Hoshida
  • Patent number: 8873970
    Abstract: A method for generating a 400 Gb/s single channel optical signal from multiple modulated subchannels includes carving respective modulated subchannels into return-to-zero RZ modulated subchannels having non-overlapping peaks with intensity modulators having a duty cycle less than 50%, and combining the subchannels into a single channel signal aggregating the bit rate of each of the subchannels. The subchannels are combined with a flat top optical component for increased subsequent receiver sensitivity.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: October 28, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Jianjun Yu, Dayou Qian, Philip Nan Ji, Ting Wang
  • Patent number: 8867924
    Abstract: A method is provided to lower the overall power consumption of small form-factor pluggable (SFP) transceivers. The method includes receiving an indication to operate the SFP transceiver in a low power mode, and setting the SFP transceiver to a low power mode in response to the indication by at least switching off a thermal electric cooler (TEC) that controls a temperature of a laser diode of the SFP transceiver. The proposed method may be implemented whenever a reach is not more than a predetermined distance, for example, 65 kilometers. At such reduced distances, the TEC of the SFP transceiver can be switched off while still guaranteeing link functionality. The instant low power mode has the benefit of reducing the power consumption of the SFP transceiver so that, for example, host platforms with lower power delivery budgets can support the SFP transceiver for at least some applications.
    Type: Grant
    Filed: September 30, 2010
    Date of Patent: October 21, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Carlo Mariotti, Damiano Rossetti, Carlo Tosetti, Federico Fontanella
  • Publication number: 20140301742
    Abstract: A digital signal processing method has steps of pre-emphasizing a digital signal, and then processing the pre-emphasized digital signal through a non-linear device. In the pre-emphasizing step, an undershoot is applied to a first level of the digital signal at a positive signal transition or an overshoot is applied to the digital signal at a negative first signal transition.
    Type: Application
    Filed: April 3, 2014
    Publication date: October 9, 2014
    Applicant: TYCO ELECTRONICS SVENSKA HOLDINGS AB
    Inventors: Marek Grzegorz Chacinski, Nicolae Pantazi Chitica
  • Patent number: 8824898
    Abstract: For providing circuit arrangement and method for transmitting signals from a data source to a data sink, the signals being TMDS encoded, the driver circuit is supplied by a connection interface, connected upstream, assigned to data source, with supply voltage, electrical TMDS encoded signals are electro-optically converted by an LED connected downstream of the driver circuit and coupled into an optical fiber as light supplied with TMDS encoded signals, the direct current portion supplied from TMDS transmitter to connection interface, to data source, is converted by driver circuit to a modulated signal current for controlling LED.
    Type: Grant
    Filed: April 8, 2011
    Date of Patent: September 2, 2014
    Assignee: SILICON LINE GmbH
    Inventors: Martin Groepl, Holger Hoeltke
  • Patent number: 8818193
    Abstract: An embodiment of the invention includes a tunable optical dispersion compensator (TODC) comprising a first beam displacer on an optical path, wherein the first beam displacer separates an optical signal into a first beam and a second beam, and one or more polarizing beam splitters on the optical path, wherein the one or more polarizing beam splitters keep the first beam and the second beam on the optical path. The TODC also comprises one or more etalons on the optical path, wherein the one or more etalons are tunable to introduce a group delay in the first beam and the second beam, and a reflecting mirror on the optical path, wherein the reflecting mirror returns the optical signal back along the optical path. The TODC further comprises a second beam displacer, wherein the second beam displacer combines the first beam and the second beam into an output optical signal.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: August 26, 2014
    Assignee: Finisar Corporation
    Inventors: Fan Chen, Yongkang Hu, Zhenli Wen, Dongshen Han, Fahua Lan, Kevin Dapeng Zhang
  • Patent number: 8818206
    Abstract: The present disclosure provides electrical domain suppression of linear crosstalk in optical communication systems using single-carrier implementations. This electrical domain suppression applies spectral shaping in the electronic radio frequency (RF) domain. Advantageously, spectral shaping in the electronic RF domain transfers system complexity from the bulk optical domain into the highly integrated CMOS (or equivalent) domain. The spectral shaping can include electronic circuitry including an electrical filtering block and a signal linearization block prior to optical modulation. The electrical filtering block suppresses coherent interference terms and can include an RF-domain low pass filter. The signal linearization block linearizes modulator response to compensate spectral regrowth due to nonlinear mixing in the modulator.
    Type: Grant
    Filed: June 24, 2009
    Date of Patent: August 26, 2014
    Assignee: Ciena Corporation
    Inventor: Michael Y. Frankel
  • Patent number: 8818203
    Abstract: An optical modulator includes a light input/output unit receiving an incident optical signal which has not been modulated, splitting the incident optical signal into a first optical signal and a second optical signal, and transmitting the first and second optical signals to a first path and a second path, respectively, of an optical waveguide. A phase shifter is positioned in at least one of the first and second paths and modulates a phase of at least one of the first and second optical signals, which have been received through the first and second paths, respectively, in response to an electrical signal. A phase-modulated signal is output. A reflective grating coupler reflects signals respectively received through the first and second paths back along the first and second paths respectively.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: August 26, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-Chul Ji, Kyoung Ho Ha, Dong Jae Shin, Jung Hyung Pyo, Kwang Hyun Lee
  • Patent number: 8805198
    Abstract: An optical transmission and reception system in which a plurality of tributary signals are converted into multilevel modulated light for transmission and reception. An apparatus for transmitting multilevel modulated light includes: FECs which perform error correction processing including addition of a tributary identifier; and a GEAR BOX which performs rate conversion on the processed signals.
    Type: Grant
    Filed: April 13, 2009
    Date of Patent: August 12, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventor: Takashi Mizuochi
  • Patent number: 8805209
    Abstract: In one embodiment, a method for performing nonlinearity compensation on a dispersion-managed optical signal that was transmitted over an optical communication link, the method including virtually dividing the communication link into a plurality of steps, performing lumped dispersion compensation on a received optical signal to obtain a waveform upon which digital backward propagation (DBP) can be performed, performing DBP by performing dispersion compensation and nonlinearity compensation for each step, and generating an estimate of the transmitted signal based upon the performed DBP.
    Type: Grant
    Filed: February 24, 2012
    Date of Patent: August 12, 2014
    Inventors: Guifang Li, Likai Zhu
  • Patent number: 8805196
    Abstract: A communications link for carrying data between a transmitter and a receiver operates according to a communications protocol (such as PCI Express (PCIe)) specifying a reduced-power link operating state in which the transmitter generates a reduced-amplitude electrical output signal and the receiver is to operate in a power-save mode. The communications link includes an electro-optical link and a circuit coupling an output of the transmitter to an electrical input of the electro-optical link. The circuit is configured to detect initiation of the reduced-power operating state and to send messages to the receiver to maintain a normal amplitude of an optical signal on the electro-optical link.
    Type: Grant
    Filed: September 30, 2010
    Date of Patent: August 12, 2014
    Assignee: Teradyne, Inc.
    Inventor: Marlon Zbigniew Kasprzyk