Patents Examined by Danny Leung
  • Patent number: 9686020
    Abstract: A signal processing device that processes a digital signal formed by sampling an electric signal using a clock signal, the electric signal being obtained by converting an optical signal inputted from a transmission line, the signal processing device includes: a first chromatic dispersion compensator that compensates a waveform distortion caused by a chromatic dispersion with respect to the digital signal; a first nonlinear optical effect compensator that compensates a waveform distortion caused by a nonlinear optical effect with respect to one signal outputted from the first chromatic dispersion compensator; and a controller that detects a phase fluctuation of other signal outputted from the first chromatic dispersion compensator, and controls the clock signal based on the detected phase fluctuation.
    Type: Grant
    Filed: August 4, 2015
    Date of Patent: June 20, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Hikari Mochizuki, Takeshi Hoshida, Osamu Takeuchi
  • Patent number: 9685762
    Abstract: Described herein are photonic integrated circuits (PICs) comprising a semiconductor optical amplifier (SOA) to output a signal comprising a plurality of wavelengths, a sensor to detect data associated with a power value of each wavelength of the output signal of the SOA, a filter to filter power values of one or more of the wavelengths of the output signal of the SOA, and control circuitry to control the filter to reduce a difference between a pre-determined power value of each filtered wavelength of the output signal of the SOA and the detected power value of each filtered wavelength of the output signal of the SOA.
    Type: Grant
    Filed: September 30, 2015
    Date of Patent: June 20, 2017
    Assignee: Aurrion, Inc.
    Inventors: Erik Johan Norberg, John M. Garcia, Brian Koch, Gregory Alan Fish
  • Patent number: 9673893
    Abstract: When an unsafe port with a loss of signal is detected, a transceiver may enable one laser in a group of lasers associated with the unsafe port and may disable the remaining lasers. Then, the transceiver may instruct a transmitter associated with the one laser to transmit an optical signal on the unsafe port using a reduced transmit power that is less than a threshold value associated with the Class 1 conditions and at a different time than enabled lasers in other groups of lasers. Alternatively, for a safe port on which valid communication is received, the transceiver may enable lasers in a group of lasers associated with the safe port. Then, the transceiver may instruct transmitters associated with the lasers in this group of lasers to transmit optical signals on the safe port using a normal transmit power for the lasers that is greater than the threshold value.
    Type: Grant
    Filed: July 31, 2015
    Date of Patent: June 6, 2017
    Assignee: ORACLE INTERNATIONAL CORPORATION
    Inventors: Patrick J. Decker, Ashok V. Krishnamoorthy, Xuezhe Zheng, Ola Torudbakken
  • Patent number: 9674592
    Abstract: The present invention relates to passive optical network (PON), and in particular, to an optical network terminal (ONT) in the PON system. In one embodiment, the optical network terminal includes a first interface coupled to a communications network, a second interface coupled to a network client and a processor including a memory coupled to the first interface and to the second interface, wherein the processor is capable of converting optical signals to electric signals, such that the network client can access the communications network.
    Type: Grant
    Filed: August 11, 2011
    Date of Patent: June 6, 2017
    Assignee: Tejas Networks Limited
    Inventor: Govindan Kutty Thrithala
  • Patent number: 9667346
    Abstract: An optical transmission system includes: a transmission node to transmit wavelength-multiplexed light of a plural wavelengths arranged in a predetermined transmission band; and a reception node to receive the wavelength-multiplexed light, and to include a monitor to monitor a detection sensitivity indicating a sampling phase shift with respect to a phase of light corresponding to one among the received plural wavelengths, and a transmitter to transmit information indicating that the monitored detection sensitivity for light corresponding to a wavelength adjacent to an outer edge of the transmission band, among the plural wavelengths, has been reduced below a threshold value, to the transmission node, wherein the transmission node includes a receiver to receive information indicating a reduction in the detection sensitivity, and a controller to stop wavelength control of shifting the wavelength adjacent to the outer edge in a direction approaching the outer edge in response to reception of the information.
    Type: Grant
    Filed: January 4, 2016
    Date of Patent: May 30, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Hirofumi Araki, Taku Saito, Yoshitaka Taki, Satoru Miyazaki
  • Patent number: 9654744
    Abstract: The present invention is directed towards a frequency modulated (FM) burst mode optical system that allows optical signals having a common wavelength provided by a plurality of FM burst mode optical transmitters to be passively combined onto a single optical fiber. A single FM optical receiver receives the combined signals and processes them accordingly. Each FM burst mode optical transmitter includes an FM modulator, a carrier detect circuit and a laser. The FM modulator modulates a carrier signal, such as a 1.21 GHz signal, with received reverse electrical signals. When a subcarrier signal is detected by the carrier detect circuit, the laser is turned and the frequency modulated carrier signal is used to intensity modulate a laser to provide an optical signal. Due to the burst-mode transmission of optical signals, the optical signals can be passively combined and transmitted to a single optical receiver.
    Type: Grant
    Filed: September 17, 2012
    Date of Patent: May 16, 2017
    Assignee: Cisco Technology, Inc.
    Inventor: Lamar E. West, Jr.
  • Patent number: 9647827
    Abstract: An apparatus comprises a photonic oscillator circuit configured to generate optical signals that are separated by a uniform delay; radio frequency (RF) generating circuitry configured to receive the optical signals and produce a series of reference clock signals having a same clock signal frequency, wherein each reference clock signal in the series includes a uniform delay from a previous clock signal in the series; and a plurality of analog-to-digital converter (ADC) circuits, wherein an ADC circuit includes a signal input to directly receive an RF input signal that is continuous in time and amplitude, and a clock input to receive a reference clock signal of the repeating series of reference clock signals, wherein the ADC circuits are configured to sample a RF input signal at the frequency of the reference clock signal with the uniform delay to sample interleaved digital values representing the RF signal.
    Type: Grant
    Filed: October 23, 2015
    Date of Patent: May 9, 2017
    Assignee: Raytheon Company
    Inventors: Steven R. Wilkinson, Bishara Shamee
  • Patent number: 9647768
    Abstract: A monolithic Receiver Optical Sub-Assembly (ROSA) device is provided and a method for producing the device. The device comprises: at least one antenna configured to receive optical signals; at least one rectifier configured to rectify electrical signals being electrical representation of the received optical signals and having frequencies within an optical band range; and at least one amplifier, coupled to the rectifier and configured to amplify rectified electrical signals; and wherein the ROSA is also characterized in being a single monolithic device.
    Type: Grant
    Filed: November 27, 2013
    Date of Patent: May 9, 2017
    Assignee: PLANXWELL LTD.
    Inventor: David Ben-Bassat
  • Patent number: 9647770
    Abstract: A photonic oscillator can produce a multifrequency optical signal having a spectrum that includes regularly spaced spectral lines. A photodetector can convert the multifrequency optical signal to a multifrequency electrical signal having a spectrum that includes the regularly spaced spectral lines. A bandpass filter can attenuate all but one spectral line of the spectrum of the multifrequency electrical signal to form a single-frequency electrical signal having leading/trailing edges that have the same precision as the photonic oscillator. A continuous-wave laser can lock to the multifrequency optical signal and produce a continuous-wave optical signal at a wavelength precisely locked to the photonic oscillator. A data encoder/decoder can modulate/demodulate a data stream onto/from the continuous-wave optical signal at a data rate of the single-frequency electrical signal. The modulated optical signal can be clocked with the leading/trailing edges of the single-frequency electrical signal.
    Type: Grant
    Filed: October 23, 2015
    Date of Patent: May 9, 2017
    Assignee: Raytheon Company
    Inventors: Steven R. Wilkinson, Bishara Shamee
  • Patent number: 9647771
    Abstract: Systems and methods for wavelength optimization for underwater optical communication can include a plurality of n lasers having different wavelengths ?i for i=1 to n, a beam splitter and a corner retro-reflector. The plurality of n lasers can simultaneously illuminate the beam splitter along a coincident axis. The plurality of n lasers can be selectively blocked so that only one laser wavelength ?i at a time impinges on the beam splitter. A portion passes through the beam splitter to establish a reference signal, while the remainder is reflected off the corner retro-reflector. A portion of return illumination passes through the beam splitter to establish a return signal. The process can be repeated for each of n lasers for i=1 to n. The ?i wavelength where the normalized signal-to-noise differential between the reference signal and return signal is the minimum can be the optimum communication wavelength.
    Type: Grant
    Filed: March 29, 2016
    Date of Patent: May 9, 2017
    Assignee: The United States of America, as Represented by the Secretary of the Navy
    Inventors: Burton H. Neuner, III, Alexandru Hening, Bienvenido Melvin Pascoguin
  • Patent number: 9641279
    Abstract: We disclose an optical transport system configured to transport data using a PDM-modulation format, in which each of two orthogonal polarizations is independently amplitude-modulated, and the relative phase between the carrier waves of the two polarizations may also be modulated. This modulation format enables the optical receiver to perform direct optical detection using a Stokes-vector detector to fully recover the encoded data.
    Type: Grant
    Filed: January 14, 2015
    Date of Patent: May 2, 2017
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Po Dong, Chongjin Xie, Young-Kai Chen
  • Patent number: 9634764
    Abstract: An estimating device includes a detector and an estimator. The detector detects a first parameter representing a ratio of a power of a signal component in received light to a power of a noise component in the received signal, a second parameter representing a sum of the power of the signal component and the power of the noise component, and a third parameter representing a sum of a power of a component being derived from cross phase modulation and being contained in the noise component and a power of a component being derived from spontaneously emitted light and being contained in the noise component. The estimator estimates, based on the first through the third parameters, a fourth parameter representing a ratio of the power of the signal component to a power of a component being derived from self phase modulation and being contained in the noise component.
    Type: Grant
    Filed: January 6, 2016
    Date of Patent: April 25, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Tomofumi Oyama, Hisao Nakashima
  • Patent number: 9634767
    Abstract: A bidirectional WDM optical communications link has WDM signals sent in opposite directions along a shared optical path and using at least one common wavelength. An optical amplifier (20, 21, 22, 70, A1D, A2U, A2D) optically amplifies (144) a first WDM signal separately from a second WDM signal in the other direction. This separated optical amplification is controlled (134) according to indications of transmission quality at the common wavelength, to alter the relative optical powers of the first and second WDM signals to enable crosstalk at the common wavelength to be limited. Cross talk at the common wavelength can be improved by rebalancing relative amounts of cross talk in the different directions, to enable the capacity benefits of using a common wavelength for both directions to be obtained while using greater optical signal power. This is particularly useful where the optical power is asymmetric, such as in WDM PON systems.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: April 25, 2017
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Luca Giorgi, Fabio Cavaliere, Fabio Falconi
  • Patent number: 9628180
    Abstract: A system may include an optical transmitter and an optical receiver. The optical transmitter may generate optical signals associated with sub-carriers, and may provide the optical signals via an optical link. The optical receiver may receive the optical signals via the optical link, and may generate samples based on the optical signals. The samples may be associated with the sub-carriers. The optical receiver may combine the samples to form a time domain sample vector having a particular size, and may generate a frequency domain sample vector, having the particular size, based on the time domain sample vector. The optical receiver may demultiplex the frequency domain sample vector to generate domain sample vectors corresponding to the sub-carriers. The optical receiver may process the frequency domain sample vectors to generate equalized frequency domain sample vectors, and may output the equalized frequency domain sample vectors.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: April 18, 2017
    Assignee: Infinera Corporation
    Inventors: Han H. Sun, Kuang-Tsan Wu, David J. Krause, Yuejian Wu
  • Patent number: 9628177
    Abstract: Light-based communication (LCom) techniques are disclosed for adaptively adjusting the baud rate of a luminaire to optimize the LCom signal transmitted for an intended receiver device. The adaptive baud rate can be adjusted by a process that includes, for example: determining decoding parameters of the receiver device, the device including a camera for receiving LCom signals, and a display. The process further includes calculating a baud rate suitable for the receiver device based on the decoding parameters, and causing the baud rate to be set at the luminaire. The process may further include at least one of: verifying the baud rate at the receiver device; adjusting the decoding parameters of the receiver device if baud rate cannot be adjusted to meet a current configuration of decoding parameters; and prompting a user to rotate receiver device to improve orientation of the luminaire with respect to a raster direction of the camera.
    Type: Grant
    Filed: September 30, 2015
    Date of Patent: April 18, 2017
    Assignee: OSRAM SYLVANIA Inc.
    Inventors: Christian Breuer, Anant Aggarwal, Barry Stout
  • Patent number: 9621967
    Abstract: Optical networking has become ubiquitous in providing low cost, high speed communications networks supporting our communication needs from FTTH through long haul to undersea. The large number of users and high speeds provided to each user fiber mean that information retrieval and routing functionality within the data centers hosting this information can become the bottleneck both in terms of speed and latency. According to embodiments of the invention the inventors present architectures based upon all-optical passive optical networks that support a distributive approach to latency reduction as well as protocols relating to their deployment. Beneficially, such POCXN concepts exploit optical components already supported by high volume manufacturing techniques as well as CWDM/DWDM techniques for throughput increase.
    Type: Grant
    Filed: November 26, 2013
    Date of Patent: April 11, 2017
    Assignee: VISCORE TECHNOLOGIES
    Inventors: Yunqu Liu, Kin-Wai Leong, Wenda Ni, Changcheng Huang
  • Patent number: 9621267
    Abstract: A visible light communication system, and a method of modulating data and a method of feeding back performance information in the system, are provided. In the system, a transmitting unit modulates a plurality of data on a plurality of LED channels basis that are formed by a plurality of LEDs, respectively, and transmits the modulated data into a corresponding light signal. A receiving unit receives a light signal that is transmitted from the transmitting unit to demodulate the received light signal to a signal on a plurality of LED channels basis.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: April 11, 2017
    Assignee: INDUSTRY ACADEMY COOPERATION FOUNDATION OF KYUNGHEE UNIVERSITY
    Inventors: Kye San Lee, Kyujin Lee, Dongho Cha
  • Patent number: 9608732
    Abstract: It becomes difficult to regenerate transmitting signals depending on modulation systems for the optical phase modulation in a polarization multiplexed optical communication system employing the optical digital coherent communication system, therefore, an optical transmitter according to an exemplary aspect of the invention includes first optical quadrature modulation means for performing a phase modulation on a first continuous light beam and outputting a first transmitting light beam; second optical quadrature modulation means for performing a phase modulation on a second continuous light beam belonging in the same frequency band as that of the first continuous light beam and outputting a second transmitting light beam; optical phase difference adding means for adding an optical phase difference varying temporally between the first transmitting light beam and the second transmitting light beam; and polarization multiplexing means for polarization-multiplexing the first transmitting light beam and the second
    Type: Grant
    Filed: February 13, 2013
    Date of Patent: March 28, 2017
    Assignee: NEC CORPORATION
    Inventor: Daisaku Ogasahara
  • Patent number: 9608759
    Abstract: An Internet Protocol/Wave Division Multiplex (IP/WDM) network implements Hardware Root of Trust (HRoT) and Network Function Virtualization (NFV). An NFV server generates and transfers IP control data and WDM control data to IP/WDM machines. The IP/WDM machines exchange IP packets between IP ports and WDM interfaces based on the IP control data. The IP/WDM machines exchange the IP packets between the WDM interfaces and WDM ports based on the WDM control data. The IP/WDM machines transmit and receive the IP packets from the WDM ports using different optical wavelengths. The IP/WDM machines transfer HRoT data indicating the optical wavelengths used to exchange the IP packets and indicating encoded hardware keys physically-embedded on the IP/WDM machines. The NFV server receives the HRoT data and process the encoded hardware keys and the optical wavelengths to validate HRoT status of the IP/WDM machines.
    Type: Grant
    Filed: May 21, 2015
    Date of Patent: March 28, 2017
    Assignee: Sprint Communications Company L.P.
    Inventors: Ronald R. Marquardt, Lyle Walter Paczkowski, Arun Rajagopal
  • Patent number: 9590731
    Abstract: A signal equalizer for compensating impairments of an optical signal received through a link of a high speed optical communications network. At least one set of compensation vectors are computed for compensating at least two distinct types of impairments. A frequency domain processor is coupled to receive respective raw multi-bit in-phase (I) and quadrature (Q) sample streams of each received polarization of the optical signal. The frequency domain processor operates to digitally process the multi-bit sample streams, using the compensation vectors, to generate multi-bit estimates of symbols modulated onto each transmitted polarization of the optical signal. The frequency domain processor exhibits respective different responses to each one of the at least two distinct types of impairments.
    Type: Grant
    Filed: July 27, 2015
    Date of Patent: March 7, 2017
    Assignee: Ciena Corporation
    Inventors: Kim B. Roberts, Han Sun