For Power Control Patents (Class 398/197)
  • Patent number: 10205532
    Abstract: A laser power controller employs: selection circuitry configured to select one of a data input value, a logical high value or a logical low value such that the selection circuitry selects the data input value during a data transmission period during a defined burst period and selects one of the logical high value and the logical low value during an extension time period during the defined burst period and immediately following the data transmission period; drive circuitry configured to apply, to a laser diode, a current corresponding to the value selected by the selection circuitry during the defined burst period or a zero value otherwise, the current being such that the laser diode is configured to provide an optical output; an optical sensor module configured to provide a sensor module output corresponding to the optical output of the laser diode, and configured to provide an electrical output proportional to the laser diode's optical output corresponding to the logical high value or the logical low value;
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: February 12, 2019
    Assignee: HILIGHT SEMICONDUCTOR LIMITED
    Inventors: William Redman-White, Dominique Coue, Colin Whitfield
  • Patent number: 10131341
    Abstract: The present invention provides a novel system and method for a power management strategy for series hybrid power systems, such as for vehicles, with limited electrical energy storage capacity that distributes instantaneous power between a source of chemical energy and a small energy storage system (ESS) efficiently. The invention provides for minimizing the energy storage system while simultaneously allowing the chemical to electrical energy converter, e.g., an internal combustion motor/engine paired with an electrical generator and/or a fuel cell power source, to operate in pre-defined efficient regions of the power user's, or vehicle's, fuel efficiency map.
    Type: Grant
    Filed: June 16, 2016
    Date of Patent: November 20, 2018
    Assignee: Mississippi State University
    Inventors: Masood Shahverdi, Michael S. Mazzola
  • Patent number: 10074961
    Abstract: A driver circuit is configured to pass a current. The circuit includes a first transistor connected in series with the laser diode, and configured to regulate the current. A voltage regulator is configured to provide an input to a gate of the first transistor so as to regulate the current in dependence upon a regulator input and a feedback input at the voltage regulator.
    Type: Grant
    Filed: March 31, 2017
    Date of Patent: September 11, 2018
    Assignee: STMICROELECTRONICS (RESEARCH & DEVELOPMENT) LIMITED
    Inventor: Denise Lee
  • Patent number: 9768865
    Abstract: An optical system includes an optical transmitter and a controller that determines a particular wavelength for a channel of the optical transmitter. The controller causes the optical transmitter to transmit a first optical signal with a first data sequence that is determined based on the particular wavelength, and determines a first optical power that is generated based on the first optical signal and the first data sequence. The controller causes the optical transmitter to transmit a second optical signal with a second data sequence that is determined based on the particular wavelength, and determines a second optical power that is generated based on the second optical signal and the second data sequence. The controller calculates a power difference between the first optical power and the second optical power, and causes the particular wavelength for the channel to be modified based on the calculated power difference.
    Type: Grant
    Filed: October 15, 2014
    Date of Patent: September 19, 2017
    Assignee: Infinera Corporation
    Inventor: Jeffrey T. Rahn
  • Patent number: 9608723
    Abstract: System and method embodiments are provided for carrier-signal power ratio (CSPR) control in direct detection optical systems. In an embodiment, a method for CSPR control in a direct detection optical system includes receiving an electrical signal in a receiver (RX) digital signal processor (DSP), wherein the electrical signal is obtained from a corresponding optical signal via a direct detection component; estimating, a CSPR for the electrical signal; generating one of a control signal according to the CSPR; and transmitting the control signal to one of an optical filter and a laser, wherein the wavelength control signal controls causes a center wavelength (CW) of one of the optical filter and the laser to be adjusted such that an offset between the CW of the laser and the CW of the optical filter results in a desired CSPR.
    Type: Grant
    Filed: October 20, 2014
    Date of Patent: March 28, 2017
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Chen Chen, Chuandong Li, Zhuhong Zhang
  • Patent number: 9529325
    Abstract: A modular routing node includes a single input port and a plurality of output ports. The modular routing node is arranged to produce a plurality of different deflections and uses small adjustments to compensate for wavelength differences and alignment tolerances in an optical system. An optical device is arranged to receive a multiplex of many optical signals at different wavelengths, to separate the optical signals into at least two groups, and to process at least one of the groups adaptively.
    Type: Grant
    Filed: December 12, 2014
    Date of Patent: December 27, 2016
    Assignee: THOMAS SWAN & CO. LTD
    Inventor: Melanie Holmes
  • Patent number: 9519151
    Abstract: An optical multiplexer and a transmitter optical subassembly are provided that relate to the field of optics communications. A light-combining part is formed by using at least one light combiner that can combine two beams of light into one beam of light, and at least two levels of light-combining parts are used to constitute an optical multiplexer, so that 2N beams of light are combined into one beam by using N level of light-combining parts, thereby reducing a package size and packaging loss, and reducing the complexity of a manufacturing process.
    Type: Grant
    Filed: December 10, 2014
    Date of Patent: December 13, 2016
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Xueming Zhang, Zhengwen Wan
  • Patent number: 9509409
    Abstract: Disclosed is an optical transceiver which includes an optical transmitter converting a first electrical signal into a first optical signal, an optical receiver converting a second optical signal into a second electrical signal, and a processing unit operatively coupled to the optical transmitter and the optical receiver. The processing unit is configured to obtain first wavelength information of the first optical signal and second wavelength information of the second optical signal and compare the first wavelength information and the second wavelength information to control a wavelength separation interval between the first optical signal and the second optical signal.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: November 29, 2016
    Assignee: OE Solutions America, Inc.
    Inventors: Wanseok Seo, Jong Ho Kim, Moon Soo Park, Joon Sang Yu
  • Patent number: 9495002
    Abstract: Embodiments include apparatuses, methods, and systems for providing a dynamic bias voltage to one or more transistors of a transceiver. In embodiments, a transceiver includes receive circuitry and transmit circuitry coupled to a same input/output (I/O) pad. A dynamic biasing circuit detects a voltage level of a data signal on the I/O pad, and generates a dynamic bias voltage having a value based on the detected voltage level. In some embodiments, the dynamic bias voltage is a selected one of a first bias voltage or a second bias voltage. The dynamic biasing circuit provides the dynamic bias voltage to one or more transistors of the transceiver to protect the transistors from electrical overstress.
    Type: Grant
    Filed: May 5, 2014
    Date of Patent: November 15, 2016
    Assignee: Intel Corporation
    Inventor: Chia How Low
  • Patent number: 9467229
    Abstract: A multilevel-intensity modulation and demodulation system includes: a digital-to-analog conversion unit to convert an output level value of a digital signal into an analog signal; a multilevel-intensity-modulated light transmission unit to transmit an optical signal multilevel-intensity modulated based on the analog signal; a multilevel-intensity-modulated light reception unit to receive the optical signal multilevel-intensity modulated, and convert the received optical signal into an analog reception electrical signal; an analog-to-digital conversion unit to convert the analog reception electrical signal into a reception level value; and a controller to convert a transmission multiple gradation level being one of a plurality of multiple gradation levels of multilevel-intensity modulation to which the digital signal is mapped, into the output level value so as to cause the reception level value to be in a desired reception state, and to receive a digital signal corresponding to a reception multiple-gradation-
    Type: Grant
    Filed: January 22, 2015
    Date of Patent: October 11, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Yutaka Kai, Masato Nishihara, Toshiki Tanaka, Tomoo Takahara
  • Patent number: 9413465
    Abstract: A receiving-side integrated optical circuit of an optical transceiver has an optical wavelength demultiplexer to separate signal light components of the different wavelengths contained in a wavelength division multiplexed signal received from each of N links of a transmission path, a set of N optical amplifiers inserted between the transmission path and the optical wavelength demultiplexer, each optical amplifier being configured to collectively amplify the signal light components of the different wavelengths contained in the received wavelength division multiplexed signal, and a set of photo detectors arranged after the optical wavelength demultiplexer and to detect the signal light components of the different wavelengths.
    Type: Grant
    Filed: November 3, 2014
    Date of Patent: August 9, 2016
    Assignee: FUJITSU LIMITED
    Inventor: Shinsuke Tanaka
  • Patent number: 9391707
    Abstract: Disclosed is an optical transceiver which includes an optical transmitter converting a first electrical signal into a first optical signal, an optical receiver converting a second optical signal into a second electrical signal, and a processing unit operatively coupled to the optical transmitter and the optical receiver. The processing unit is configured to obtain first wavelength information of the first optical signal and second wavelength information of the second optical signal and compare the first wavelength information and the second wavelength information to control a wavelength separation interval between the first optical signal and the second optical signal.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: July 12, 2016
    Assignee: OE SOLUTIONS AMERICA, INC.
    Inventors: Wanseok Seo, Jong Ho Kim, Moon Soo Park, Joon Sang Yu
  • Patent number: 9312961
    Abstract: Since it is difficult to emit a control a IQ modulator emitting modulated lightwave according to QAM format without signal degradation of said emitted signal due to low frequency dither used for the control of said modulator, a method for controlling an optical transmitter according to an exemplary aspect of the invention includes: generating a multilevel electrical signal by means of combining two or more binary electrical signals, where said multilevel signal is used to drive the modulator of adding a low frequency dither signal on several of the binary electrical signals, wherein the phase of the added dither signal depends on the value of the binary signal to which it is added; tapping a portion of light after the modulator and generating a monitor signal from the tapped light; controlling the modulator according to the monitor signal.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: April 12, 2016
    Assignee: NEC CORPORATION
    Inventor: Emmanuel Le Taillandier De Gabory
  • Patent number: 9197318
    Abstract: A method and apparatus for modulating a beam from a laser with an electro-absorption modulator, and determining the optical power of the beam by measuring a back current produced by the electro-absorption modulator. The apparatus comprises an electro-absorption modulator and a back current detector. The electro-absorption modulator receives an electronic digital signal from an electro-absorption driver. The electro-absorption modulator modulates the beam of the laser according to the electronic digital signal. While modulating the beam, the electro-absorption modulator produces a back current. This back current is proportional to the optical power of the beam. The back current detector measures the back current to determine the optical power of the beam.
    Type: Grant
    Filed: June 7, 2013
    Date of Patent: November 24, 2015
    Assignee: PMC-SIERRA US, INC.
    Inventor: Paulius Mosinskis
  • Patent number: 9173013
    Abstract: A method and a device for adjusting a laser in an optical network. At least one alive message is transmitted from a first optical component towards a second optical component. A confirmation message is transmitted from the second optical component to the first optical component determining the wavelength of the laser to be used based on the alive message received by the second optical component. Furthermore, an optical communication system is provided with an optical element.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: October 27, 2015
    Assignee: Xieon Networks S.a.r.l.
    Inventors: Harald Rohde, Sylvia Smolorz
  • Patent number: 9116367
    Abstract: A transmitter optical module implemented with an electro-absorption (EA) modulator is disclosed. The module includes an EA driver comprising a signal detector, an offset controller, and a driver circuit. The signal detector detects the existence of the modulation signal input thereto. The offset controller provides to the driver circuit the first offset to shift the cross point of the output of the driver circuit higher when the modulation signal exists; while, the second offset when the modulation signal disappear. The second offset lowers the output of the driver circuit to prevent the excess optical output of the transmitter optical module.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: August 25, 2015
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Taizo Tatsumi, Keiji Tanaka
  • Patent number: 9109776
    Abstract: The present invention is a segmented LED lighting system. In particular, the present invention is directed to a set of channel segments connected by a flexible lens sleeve that can be positioned in a variety of ways. A printed circuit board with at least one LED is mounted in each channel segment. Each segment preferably has a base with two ribbed vertical sides. The lens sleeve is preferably coextruded from flexible acrylic and has opaque side grips that grip the ribbed vertical sides and a translucent lens portion with an air gap. Pairs of encapsulated PCB modules are preferably connected in series to allow the system to be cut in the field.
    Type: Grant
    Filed: October 5, 2012
    Date of Patent: August 18, 2015
    Inventor: Gregory S. Smith
  • Patent number: 9048947
    Abstract: A fiber optic communication system includes a first fiber optic device configured to transmit a fiber optic signal. A second fiber optic device is in fiber optic communication with and configured to receive the fiber optic signal from the first fiber optic device. The second fiber optic device includes an adjustment circuit configured to automatically adjust the fiber optic signal if the fiber optic signal is transmitted outside of a predetermined signal strength range.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: June 2, 2015
    Assignee: Verizon Patent and Licensing Inc.
    Inventor: Koutoung Chou
  • Patent number: 9037000
    Abstract: A fiber optic data transmission system includes an optical fiber and a data transmitter having a first laser having a first wavelength, a first phase modulator for phase modulating light from the first laser as a function of a first data input stream so as to create a first phase-modulated output data stream, a second laser having a second wavelength different from the first wavelength, and a second phase modulator for phase modulating light from the second laser as a function of a second data input stream so as to create a second phase-modulated output data stream. The transmitter also includes a combiner combining the first and second output data streams into a phase-modulated optical signal for transmission over the optical fiber.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: May 19, 2015
    Assignee: TQ GAMMA, LLC
    Inventor: Peter Snawerdt
  • Patent number: 9037002
    Abstract: A pre-emphasis control method includes calculating an average value of transmission characteristics based on transmission characteristics of a plurality of light beams received by a receiver, and determining that, among signals of the plurality of light beams, a wavelength with a deviation from the average value is a wavelength at which control is to be performed, determining that the wavelength at which control is to be performed and a wavelength adjacent thereto are a group of wavelengths at which control is to be performed, obtaining an average of transmission characteristics of the group of wavelengths at which control is to be performed, and based on a difference between averaged transmission characteristics and respective transmission characteristics of the group of wavelengths at which control is to be performed, changing a light intensity output from each transmitter that transmits a group of wavelengths at which control is to be performed.
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: May 19, 2015
    Assignee: FUJITSU LIMITED
    Inventors: Jyunji Tanaka, Shinichi Kaneko, Takeo Osaka
  • 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: 9031418
    Abstract: A communication system including: a transmission apparatus configured to modulate a first light by using a first signal to be transferred and a second signal having a frequency different from a frequency of the first signal so as to generate a first optical signal, modulate a second light by using a third signal to be transferred and a fourth signal having a frequency different from a frequency of the third signal so as to generate a second optical signal, polarization-multiplex the first optical signal and the second optical signal, and transmit a polarization-multiplexed optical signal in which the first optical signal and the second optical signal are polarization-multiplexed, each of the first light and the second light being polarized; and a measuring apparatus configured to measure powers of the second signal and the fourth signal which are included in the polarization-multiplexed optical signal transmitted from the transmission apparatus.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: May 12, 2015
    Assignee: Fujitsu Limited
    Inventors: Masahiro Yuki, Takafumi Terahara, Norifumi Shukunami
  • 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: 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
  • Patent number: 8971362
    Abstract: A power monitoring and correction to a desired power level of a laser or group of lasers utilizes two photodetectors which are employed to accurately determine the amount of output power from the front end or “customer” end of a laser or a plurality of such lasers. During power detection, which may be accomplished intermittently or continuously, the laser is modulated with a tone of low frequency modulation. One photodetector at the rear of the laser is employed to detect the DC value of the frequency tone, i.e., a value or number representative of the AC peak-to-peak swing, amplitude or modulation depth of the tone. Also, the rear photodetector may be employed to determine the optical modulation index (OMI). In either case, these values may be employed in a closed loop feedback system to adjust or otherwise calibrate the value of the low tone frequency relative to the total desired bias current applied to the laser.
    Type: Grant
    Filed: April 12, 2010
    Date of Patent: March 3, 2015
    Assignee: Infinera Corporation
    Inventors: Robert W. Smith, Alan C. Nilsson
  • Patent number: 8971705
    Abstract: A method and system for transient and switching stabilization of a fiber optic transport system. One or more data-bearing channels are coupled to an optical fiber. The data-bearing channels are distributed among a plurality of frequency sub-bands. A set of control channels is also coupled to the optical fiber. Each control channel includes a pair of signals at separate frequencies. There is at least one control channel in each of the plurality of frequency sub-bands. The pair of signals of a control channel are cross-polarized. Optical power in at least one of the plurality of sub-bands is measured. Responsive to the measured optical power, the optical power of a control channel is adjusted to maintain a substantially constant power of a sub-band that contains the adjusted control channel.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: March 3, 2015
    Assignee: Ciena Corporation
    Inventors: David Boertjes, Loren Berg
  • Patent number: 8958705
    Abstract: A method of operating an optical amplifier includes determining a gain of the optical amplifier and providing a modulator drive signal to an optical signal source. The modulator drive signal is a function of the gain of the optical amplifier. The method also includes producing an input optical signal using the optical signal source. The input optical signal includes a first plurality of pulses, each of the first plurality of pulses having an amplitude related to the modulator drive signal. The method further includes coupling the input optical signal to the optical amplifier and amplifying the input optical signal using the optical amplifier to produce an output optical signal including a second plurality of pulses.
    Type: Grant
    Filed: January 13, 2012
    Date of Patent: February 17, 2015
    Assignee: ESI-Pyrophotonics Lasers Inc.
    Inventors: Guillaume Blanchette, Richard Murison, Benoit Reid
  • 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: 8934778
    Abstract: The object of the present invention is to reliably prevent deterioration and failure of reception relevant parts in a transmission apparatus on a reception side without using an attenuator. An output value control method that controls an output value of output information transmitted from each of transmission apparatuses, in which a transmission apparatus transmits the output information having a minimum output value as the output value to the other transmission apparatus, and when the output information does not reach the other transmission apparatus, the transmission apparatus repeats transmission of the output information after increasing the own output value by adding a predetermined value to a previous output value, and then the other transmission apparatus that has received the output information calculates the output value of the transmission apparatus, and notifies the calculated output value of the transmission apparatus as an appropriate output value to the transmission apparatus.
    Type: Grant
    Filed: November 20, 2012
    Date of Patent: January 13, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Yusho Futami, Kazuhiro Watanabe
  • 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: 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
  • Patent number: 8842999
    Abstract: Provided is an optical network unit saving power. The optical network unit may include a processor checking whether at least one downward physical block, the upward physical block and a data switching block operate in an idle mode, sequentially transiting at least one downward physical block, an upward physical block and a data switching block to a sleep mode according to the checking result and sequentially transiting an optical transmission-reception block and the medium access control block to a sleep mode by judging whether or not a medium access control block transits to a sleep mode.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: September 23, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sung Chang Kim, Geun Yong Kim, Hark Yoo, Youngsuk Lee, Sim-Kwon Yoon, Jong Deog Kim
  • Patent number: 8824903
    Abstract: A method for an optical transmitter, receiver or transceiver allowing determination of a signal property of a first binary signal such as the modulation amplitude. The method applies a reference stage which is modulated by the signal content of the first binary signal to allow the determination.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: September 2, 2014
    Assignee: Mellanox Technologies Denmark APS
    Inventor: Steen Bak Christensen
  • 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
  • Patent number: 8798464
    Abstract: A method of determining a power correction factor for an optical power of an optical channel of a wavelength division multiplexed communications network. The method comprises configuring an optical source of the communications network to generate an unmodulated optical carrier signal for the optical channel. The method further comprises determining the optical power of the unmodulated optical carrier signal (PHIGH). The method further comprises configuring the optical source to apply a test modulation pattern to the optical carrier signal, to generate a modulated optical carrier signal. The method further comprises determining the optical power of the modulated optical carrier signal (PMOD). The method further comprises determining a power correction factor for the optical channel by determining the difference between the optical powers of the unmodulated optical carrier signal and the modulated optical carrier signal.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: August 5, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Gianmarco Bruno, Riccardo Ceccatelli, Edoardo Mongiardini
  • Patent number: 8798482
    Abstract: An infrared transmitter is obtained that transmits a signal by changing a luminance of an infrared emitting LED, the infrared transmitter including: a transmission signal generating unit; a biasing voltage generating unit that generates a biasing voltage according to a magnitude of a transmission signal; a signal/voltage mixing unit that mixes the transmission signal and the biasing voltage; and a voltage-current conversion unit that converts a voltage into a current, in which the LED is driven by the current obtained by the conversion in the voltage-current conversion unit, so that power consumption efficiency can be improved.
    Type: Grant
    Filed: September 11, 2008
    Date of Patent: August 5, 2014
    Assignee: Kabushiki Kaisha Audio-Technica
    Inventor: Tatsuji Harima
  • Patent number: 8792792
    Abstract: [PROBLEM] Providing an optical source that outputs optical frequency modulated light having a constant output optical intensity. [MEANS FOR SOLVING THE PROBLEM] Provided is a light source apparatus that outputs an optical signal having an optical frequency corresponding to a frequency control signal, the light source apparatus including a laser light source section that outputs laser light having an optical frequency corresponding to the frequency control signal; and an optical intensity adjusting section that compensates for intensity change of the laser light to output laser light in which the intensity change caused by a change in the optical frequency is restricted.
    Type: Grant
    Filed: October 18, 2011
    Date of Patent: July 29, 2014
    Assignee: Advantest Corporation
    Inventors: Shin Masuda, Kazunori Shiota
  • Patent number: 8774568
    Abstract: Provided is an optical module. The optical module includes: an optical bench having a first trench of a first depth and a second trench of a second depth that is less than the first depth; a lens in the first trench of the optical bench; at least one semiconductor chip in the second trench of the optical bench; and a flexible printed circuit board covering an upper surface of the optical bench except for the first and second trenches, wherein the optical bench is a metal optical bench or a silicon optical bench.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: July 8, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Young-Tak Han, Jang Uk Shin, Sang-Pil Han, Sang Ho Park, Yongsoon Baek
  • Patent number: 8774643
    Abstract: A driver circuit configured to generate a drive signal for an optical source comprises an overshoot controller that provides an amount of overshoot for a given logic state of the drive signal as a function of a duration of at least one previous logic state of the drive signal. The drive signal may alternate between a first logic state associated with a first operating mode of the optical source and a second logic state associated with a second operating mode of the optical source. The overshoot controller may be configured to provide amounts of overshoot for respective instances of the first logic state that are proportional to the durations of their respective immediately preceding second logic states. The driver circuit may be implemented in a heat-assisted magnetic recording system in which the optical source alternates between on and off states associated with respective magnetic write and magnetic read modes.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: July 8, 2014
    Assignee: LSI Corporation
    Inventors: Jason P. Brenden, Xuemin Yang, Cameron C. Rabe
  • Publication number: 20140186056
    Abstract: Systems and methods are provided for a low frequency AC comparison circuit. The low frequency AC comparison circuit includes circuitry configured to receive a monitoring signal generated by an optical detector, the monitoring signal being proportional to an amount of light generated by an optical transmission device that transmits based on a data signal that is received by an optical driver. The comparison circuit is further configured to generate a modulation current control signal that is transmitted to the optical driver based on a comparison of a low frequency AC component of the monitoring signal and a correlated low frequency AC component of the data signal.
    Type: Application
    Filed: August 27, 2013
    Publication date: July 3, 2014
    Inventor: Jonah Nuttgens
  • Patent number: 8768166
    Abstract: Adaptive power setting techniques for optical transceivers are provided. Optical signals are received at a first optical transceiver device that are transmitted from a second optical transceiver device. A receive power of the optical signals received at the first optical transceiver device from the second optical transceiver device is determined. A characteristic of optical signals transmitted by the first optical transceiver device to the second optical transceiver device is modulated to indicate to the second optical transceiver device a disparity of the receive power with respect to a target receive power level at the first optical transceiver device. Conversely, the first optical transceiver device adjusts a power level of optical signals transmitted by the first optical transceiver device to the second optical transceiver device based on a characteristic of the optical signals received at the first optical transceiver device.
    Type: Grant
    Filed: April 15, 2011
    Date of Patent: July 1, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Mahan Movassaghi, Norman Tang, Liang Ping Peng
  • Patent number: 8768179
    Abstract: A power management arrangement for low power optical transceiver such as those that may be integrated into a personal computer or server may periodically put itself into a power conservation or sleep mode which assures the transceiver is available upon wake-up.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: July 1, 2014
    Assignee: Intel Corporation
    Inventors: Hui-chin Wu, Miaobin Gao, Hengju Cheng
  • Patent number: 8750707
    Abstract: In general, a system and method provides secure communications between optical transceivers in an optical communication system. Two or more optical transceivers may be provisioned with one or more passcodes assigned to the transceivers, which may be used to indicate that received data traffic is intended for the transceivers. The transceivers may be configured to format data traffic with a secure version of the passcode in the overhead of the outbound signal and may be configured to determine if an inbound signal includes a secure version of the passcode provisioned in that transceiver. A transceiver may prevent data traffic from being read when the transceiver is not provisioned to receive data traffic with the embedded secure passcode and may insert an alternative maintenance signal (AMS) into an outbound signal in an opposite direction, at least temporarily, until the inbound signal includes the appropriate passcode.
    Type: Grant
    Filed: April 13, 2011
    Date of Patent: June 10, 2014
    Assignee: Tyco Electronics Subsea Communications LLC
    Inventors: Sameh A. Sabet, Jonathan M. Liss
  • Patent number: 8750711
    Abstract: Systems and methods for performing closed-loop diagnostics in optical transceiver. The TOSA of an optical receiver includes a primary transmit module and a secondary receiver module. The transmit module transmits a data signal to a ROSA of another optical transceiver. The ROSA has a secondary transmit module that can transmit a diagnostic data signal back to the secondary receiver module of the TOSA. The TOSA can use the diagnostic data received from the ROSA to automatically adjust itself and perform closed-loop feedback functions. The closed loop diagnostics can be implemented in a network where one transceiver may be connected with more than one other transceiver in a multi-node configuration.
    Type: Grant
    Filed: August 15, 2011
    Date of Patent: June 10, 2014
    Assignee: Finisar Corporation
    Inventor: John Hsieh
  • Patent number: 8750714
    Abstract: Monolithic single and/or dual detector structures are fabricated on the emitting surface of a VCSEL and/or on a lens or glass substrate configured to be positioned along the axis of emission of an optical light source. Each monolithic detector structure includes one or two PIN detectors fabricated from amorphous silicon germanium with carbon doping or amorphous germanium with hydrogen doping. The monolithic detectors may additionally include various metallization layers, buffer layers, and/or anti-reflective coatings. The monolithic detectors can be grown on 1550 NM VCSELs used in optical transmitters, including lasers with managed chirp and TOSA modules, to reduce power and real estate requirements of the optical transmitters, enabling the optical transmitters to be implemented in long-reach SFP+ transceivers.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: June 10, 2014
    Assignee: Finisar Corporation
    Inventors: Henry M. Daghighian, Kevin J. McCallion
  • Patent number: 8676063
    Abstract: A quantum correlated photon pair generating device includes a nonlinear optical medium that generates quantum correlated photon pairs from excitation light by spontaneous parametric fluorescence and generates auxiliary idler light from the excitation light and auxiliary signal light by stimulated parametric conversion. The excitation light and auxiliary signal light are generated separately, combined, and input simultaneously to the nonlinear optical medium. An optical demultiplexer separates the auxiliary signal light and the auxiliary idler light output from the nonlinear optical medium. The intensities of the output auxiliary signal light and auxiliary idler light are detected, and the intensity or wavelength of the excitation light or the temperature of the nonlinear optical medium is controlled to maintain the ratio of the detected intensities at a preset value. The rate at which the quantum correlated photon pairs are generated is thereby held steady.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: March 18, 2014
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Shin Arahira
  • Patent number: 8670676
    Abstract: The invention relates to an optical modulator control system implemented in an optical burst mode transmitter, said control system comprising means for measuring a plurality of optical power sample values and associated optical wavelength data values from a modulator at a first sampling rate, wherein an average power table is generated from said values for each sample period and stored in a memory. The control system also comprises means for performing a control error calculation from two or more stored average power tables at a second sampling rate to calculate a single error value to provide gain and/or bias control signals, wherein the second sample rate is sampled at a slower rate than the first sample rate. The control system described optimises the modulator performance over temperature and lifetime in an optical network.
    Type: Grant
    Filed: November 12, 2010
    Date of Patent: March 11, 2014
    Assignee: Intune Networks Limited
    Inventor: Richard Oberland
  • Patent number: 8660435
    Abstract: A system for delivering optical power over optical conduits includes more than one optical power source and an optical power distribution node configured for selectively delivering optical power to multiple optical power sinks.
    Type: Grant
    Filed: May 11, 2010
    Date of Patent: February 25, 2014
    Assignee: The Invention Science Fund I, LLC
    Inventors: Alistair K. Chan, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, Lowell L Wood, Jr.
  • Patent number: 8660437
    Abstract: A fiber optic network reduces distortion present in modulated optical signals received at an optical receiver from an optical transmitter via a fiber optic link. The optical receiver analyzes a received modulated optical signal, where the wavelength of the received signal is periodically varied at the transmitter around a center wavelength over a wavelength range. Based on the analysis, the receiver generates a link transmission curve indicative of the optical power of the received signal over the wavelength range. The network disclosed herein subsequently uses the link transmission curve to reduce the distortion caused by misalignment between the operating wavelength of a transmitter laser and a peak power wavelength at the peak power of the link transmission curve. For example, the transmitter may adjust the laser operating wavelength based on a control signal received from the receiver and generated at the receiver based on the link transmission curve.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: February 25, 2014
    Assignee: Emcore Corporation
    Inventor: Henry A. Blauvelt