Wavelength Control Patents (Class 398/95)
  • Patent number: 10230487
    Abstract: It is made possible to accommodate a plurality of services and transmit each of the accommodated services to a corresponding transmission device. An optical transmitter according to an exemplary aspect of the present invention includes sub-carrier adjusting means for outputting sub-carriers to a plurality of output ports according to a control signal; encoding processing means for mapping client data on a plurality of output lanes according to the control signal; a plurality of modulation means for modulating the sub-carriers inputted through the output ports by client data inputted through the output lanes and outputting modulated signals; and control means for generating and outputting the control signal based on transmission information.
    Type: Grant
    Filed: March 11, 2015
    Date of Patent: March 12, 2019
    Assignee: NEC CORPORATION
    Inventors: Tomoyuki Hino, Shinsuke Fujisawa, Hitoshi Takeshita, Akio Tajima
  • Patent number: 9419742
    Abstract: Consistent with one example of the disclosed implementations, a photonic integrated circuit (PIC) may be provided that includes s group of lasers and an arrayed waveguide grating (AWG) disposed on a substrate. Each laser in the group may supply an optical signal, such that each optical signal has a different wavelength. Each laser may be tunable to at least two designated wavelengths, which are separated from one another by a free spectral range (FSR) of the AWG. As a result, the optical signals provided from each laser may be combined by the AWG, regardless of which designated wavelength the optical signals have. Accordingly, a PIC may be provided that has a relatively simple construction but can supply optical signals having tunable wavelengths.
    Type: Grant
    Filed: December 30, 2011
    Date of Patent: August 16, 2016
    Assignee: Infinera Corporation
    Inventors: Radhakrishnan L. Nagarajan, Masaki Kato, Michael Francis Van Leeuwen, Timothy Butrie
  • Patent number: 9419724
    Abstract: A coherent optical receiver according to an exemplary aspect of the invention includes a coherent optical receiving part performing coherent detection by inputting and mixing local oscillation light and main signal light received through a transmission line with a signal applied at a transmitting side, outputting the signal applied to the main signal light as an electric signal, and regenerating and outputting an original signal on the basis of the electric signal; and a local oscillation optical frequency control part receiving channel information on a transmission line adjacent to the main signal light, and outputting the local oscillation light after changing a frequency of the local oscillation light depending on the presence or absence of adjacent channel signal light of other signal light in an adjacent channel.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: August 16, 2016
    Assignee: NEC CORPORATION
    Inventor: Makoto Shibutani
  • Patent number: 9379822
    Abstract: There is provided an optical receiving apparatus, including a receiver configured to perform coherent reception by mixing first light of a received optical signal and second light generated by a local oscillator, a monitor configured to monitor a first frequency of the first light, and a controller configured to control a second frequency of the second light, based on a difference between the first frequency and the second frequency so as to reduce the difference.
    Type: Grant
    Filed: March 5, 2012
    Date of Patent: June 28, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Hiroshi Iizuka, Takeshi Sakamoto
  • Patent number: 9369914
    Abstract: Systems and techniques relating to wireless signal processing.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: June 14, 2016
    Assignee: Marvell International Ltd.
    Inventors: Kedar Shirali, Ravi Narasimhan, Yungping Hsu
  • Patent number: 9270381
    Abstract: Disclosed are a method and an apparatus for transmitting and receiving coherent optical OFDM.
    Type: Grant
    Filed: November 22, 2011
    Date of Patent: February 23, 2016
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Chun Ju Youn, Yong-Hwan Kwon, Duk Jun Kim, Jong-Hoi Kim, Joong-Seon Choe, Kwang-Seong Choi, Eun Soo Nam
  • Patent number: 9124374
    Abstract: A transmitter module is disclosed, where the transmitter module includes optical sources, an optical multiplexer to multiple optical signals each output from optical sources, an optical detector to detect an output of the optical multiplexer, and a controller. The controller alternately superposes a dither signal on a bias current provided to the optical source, and the bias current is controlled based on a magnitude of the dither signal, which is detected by a configuration similar to the lock-in amplifier.
    Type: Grant
    Filed: March 21, 2014
    Date of Patent: September 1, 2015
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Keiji Tanaka, Phillip Edwards
  • Patent number: 9106361
    Abstract: The present invention relates to a passive wavelength division multiplexing device for automatic wavelength locking and a system thereof including an optical multiplexer, an optical filter, an integrated optical receiver monitor, and a tunable optical transmitter. Through wavelength locking that adjusts a wavelength of an optical signal, which changes according to an external environment such as a temperature change, into a wavelength of an optical signal having the maximum optical intensity, communication quality may be maximized by securing a stable communication channel, a locking time and a communication channel setting time may be reduced, and more robust locking may be guaranteed.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: August 11, 2015
    Assignees: SOLID, INC., SOLID SYSTEMS, INC., CHEMOPTICS, INC.
    Inventors: Ki-Woon Na, Woo-Jin Lee, Kwon-Hoon Han, Seung-Rog Choi, Tae-Hyeong Kim, Young-Ouk Noh
  • Patent number: 9088130
    Abstract: An apparatus and method for stabilizing an output of a laser is provided. An optical amplifier oscillates light having a first wavelength band. A filter filters the light having the first wavelength band to output light having a second wavelength band narrower than the first wavelength band. The light having the second wavelength band may correspond to an output of a laser. To stabilize the wavelength center of the output laser, at least a portion of the light having the second wavelength band may be transferred to a fiber Bragg Grating (FBG) through a coupler. By performing feedback of a difference between the signal output from the FBG and a laser modulation signal, an offset corresponding to a lead zirconate titanate (PZT) operating parameter of a Fabry-Perot filter may be controlled to automatically stabilize the wavelength center.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: July 21, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hong Sig Kim, Wang Yuhl Oh, Tae Hwan Kim, Jae Guyn Lim, Han Saem Cho
  • Patent number: 9031412
    Abstract: A coolerless photonic integrated circuit (PIC), such as a semiconductor electro-absorption modulator/laser (EML) or a coolerless optical transmitter photonic integrated circuit (TxPIC), may be operated over a wide temperature range at temperatures higher then room temperature without the need for ambient cooling or hermetic packaging. Since there is large scale integration of N optical transmission signal WDM channels on a TxPIC chip, a new DWDM system approach with novel sensing schemes and adaptive algorithms provides intelligent control of the PIC to optimize its performance and to allow optical transmitter and receiver modules in DWDM systems to operate uncooled. Moreover, the wavelength grid of the on-chip channel laser sources may thermally float within a WDM wavelength band where the individual emission wavelengths of the laser sources are not fixed to wavelength peaks along a standardized wavelength grid but rather may move about with changes in ambient temperature.
    Type: Grant
    Filed: November 4, 2009
    Date of Patent: May 12, 2015
    Assignee: Infinera Corporation
    Inventors: Radhakrishnan L. Nagarajan, Fred A. Kish, Jr., David F. Welch, Drew D. Perkins, Masaki Kato
  • Publication number: 20150104180
    Abstract: The present disclosure describes systems and methods for beam wavelength stabilization and output beam combining in dense wavelength multiplexing (DWM) systems. Systems and methods are described for performing beam wavelength stabilization and output beam combining in DWM systems while achieving increased wall-plug efficiency and enhanced beam quality. Interferometric external resonator configurations can be used to greatly increase the brightness of DWM system output beams by stabilizing the wavelengths of the beams emitted by the emitters of the DWM laser source. The resonant cavities described by the present disclosure provide advantages over the prior art in the form of decreased cost, increased wall plug efficiency and increased output beam quality. Particular implementations of the disclosure achieve increased wall plug efficiency and increased output beam quality through a combination of innovative cavity designs and the utilization of reflection diffraction elements for beam combining.
    Type: Application
    Filed: October 14, 2013
    Publication date: April 16, 2015
    Inventors: Hagen Zimer, Alexander Killi, Christoph Tillkorn, Steffen Ried
  • Patent number: 8891961
    Abstract: In an optical communication device, a light source is capable of varying the wavelength of light to be output. An optical multiplexer multiplexes light output from the light source with signal light received from a transmission path. To an optical medium, light output from the optical multiplexer is input. A monitor monitors light having a predetermined wavelength output from the optical medium. A wavelength number measuring unit measures the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring by the monitor.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: November 18, 2014
    Assignee: Fujitsu Limited
    Inventors: Taizo Maeda, Takashi Toyomaki, Takuya Miyashita
  • Patent number: 8886036
    Abstract: Disclosed is an optical line terminal for monitoring and controlling upstream and downstream optical signals, and more particularly, to an optical line terminal for monitoring and controlling upstream and downstream optical signals, which adds different low frequency monitoring signals to upstream and downstream wavelength division multiplexing optical signals in a bidirectional wavelength division multiplexing (WDM) optical network and senses and detects low frequency components of upstream and downstream optical signals to unite, monitor, and control optical outputs and wavelengths of the upstream and downstream wavelength division multiplexing optical signals into a single system.
    Type: Grant
    Filed: March 21, 2013
    Date of Patent: November 11, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jong Sool Jeong, Hyun Soo Kim, Mi-Ran Park, Byungseok Choi, O-Kyun Kwon
  • Patent number: 8873964
    Abstract: Optical autodiscovery is provide between two optical modules to insure that when an optical signal is coupled between the two optical module, the optical signal from a first module does not interfere with operation of a second module. The autodiscovery is implemented by sending an optical identification signal from the first optical module via the coupling to the second optical module from which signal, the second optical module can verify and determined acceptance of the coupled first optical module. During this autodiscovery process, the optical identification signal from the first optical module may be attenuated or shifted in optical spectrum so as not to interfere with the operation of the second optical module. Autodiscovery may also be employed in cases where a first optical module is to receive an optical signal from a second module.
    Type: Grant
    Filed: January 31, 2011
    Date of Patent: October 28, 2014
    Assignee: Infinera Corporation
    Inventors: Matthew L. Mitchell, Robert B. Taylor, Alan C. Nilsson, Steven Joseph Hand, Daniel P. Murphy
  • Patent number: 8818191
    Abstract: A method for reallocating a wavelength in an optical wavelength multiplexer transmission system is disclosed. The method includes switching a supply of a first channel electric signal from a first optical transmitter device to a second optical transmitter device, the first optical transmitter device converting the first channel electric signal into an optical signal of a first wavelength, and the second optical transmitter device converting the first channel electric signal into an optical signal of a second wavelength differing from the first wavelength, and transmitting the optical signal of the second wavelength output from the second optical transmitter device.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: August 26, 2014
    Assignee: Fujitsu Limited
    Inventors: Takeshi Sakamoto, Ryosuke Goto
  • Patent number: 8811819
    Abstract: Provided is a passive optical network system, wherein the electric power to be consumed is reduced on the basis of the quantity of signal to be transmitted downstream in a WDM-PON where signals having different transmission rates for wavelengths are mixed. In the passive optical network system, an OLT (200) and a plurality of ONUes (300) are connected by an optical fiber network including an optical splitter (100) and a plurality of optical fibers (110 and 120). The OLT (200) indicates to the ONUes (300) the wavelength to be used, in addition to the timing for transmission to the ONUes (300). A format for signal transmission from the OLT (200) to the ONUes (300) comprises both the region, in which the timing for transmission to the ONUes (300) indicated by the OLT (200) to the ONUes (300) is stored, and the region, by which the wavelength to be used in the communication in the direction from the OLT (200) to the ONUes (300) is indicated.
    Type: Grant
    Filed: June 16, 2009
    Date of Patent: August 19, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Kazawa, Norihiro Sakamoto, Masaki Ohira
  • Patent number: 8805187
    Abstract: An optical waveguide router device with feedback control that uses the fringe frequencies of an optical data signal to derive a wavelength (e.g., temperature) control signal in order to compensate for wavelength variations due to temperature fluctuations and/or other wavelength shifting factors without the need for a reference laser. A monitoring circuit converts an output of at least one output monitoring port to an electrical signal and comparing the output of said at least one output monitoring port against 1) a reference signal, or 2) at least one output from another output monitoring port having a higher or lower frequency fringe of an optical data signal of at least one data port, or 3) at least one output from another output monitoring port having light from diffraction pattern(s), and outputting a control signal reflecting a result of the comparison to control at least one center wavelength of the waveguide router.
    Type: Grant
    Filed: March 19, 2012
    Date of Patent: August 12, 2014
    Assignee: Neophotonics Corporation
    Inventor: Kenneth McGreer
  • Patent number: 8792788
    Abstract: Techniques, devices and systems for optical communications based on wavelength division multiplexing (WDM) that use tunable multi-wavelength laser transmitter modules.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: July 29, 2014
    Assignee: Google Inc.
    Inventors: Cedric F. Lam, Hong Liu
  • Patent number: 8781328
    Abstract: The inventive method, implemented in an optical flexible wavelength division multiplexing FWDM network, includes finding a connection route in an optical FWDM network on which a channel with sufficient spectrum is available at lowest wavelength among all available channels, finding K channels at first available K lower wavelengths out of available channels for minimizing total required spectrum; and selecting a channel which is routed through minimum number of optical fiber paths out of the K available channels at one of the lower wavelengths.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: July 15, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Ankitkumar Patel, Philip Nan Ji
  • Patent number: 8760370
    Abstract: A lighting system including a plurality of luminaires capable of generating polychromatic light having a dominant wavelength in the visible spectrum and arranged into an array and a computerized device electrically coupled to the plurality of luminaires so as to selectively operate each individual luminaire to produce source light varying with each other and with time. The computerized device operates the luminaire such that each luminaire emits a source light, the source lights combining to form a combined light having selected characteristics. The source lights, when perceived directly, recreate a lighting scenario having varying lighting characteristics.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: June 24, 2014
    Assignee: Lighting Science Group Corporation
    Inventors: Fredric S. Maxik, David E. Bartine, Robert R. Soler, Addy S. Widjaja, Matthew Regan, Eliza Katar Grove
  • Patent number: 8754832
    Abstract: A system and method for accenting regions of a layer including a lighting system including a plurality of light sources operable to emit polychromatic light and a layer having two or more regions configured to diffusively scatter light within a wavelength range while absorbing light not within the wavelength range. The regions may be configured to represent recognizable characters or images, and may form a sequence. The lighting system may highlight the regions individually or simultaneously. The layer may be attachable to a surface and may further include non-highlighted regions. The system may also include appliqués applied to a surface and a cover layer transparent to certain wavelengths of light that the appliqués scatter.
    Type: Grant
    Filed: January 30, 2013
    Date of Patent: June 17, 2014
    Assignee: Lighting Science Group Corporation
    Inventors: Fredric S. Maxik, David E. Bartine, Robert R. Soler, Mark Andrew Oostdyk, Addy S. Widjaja, Matthew Regan
  • Patent number: 8743023
    Abstract: A lighting system including a plurality of luminaires capable of generating polychromatic light having a dominant wavelength in the visible spectrum and arranged into an array and a computerized device electrically coupled to the plurality of luminaires so as to selectively operate each individual luminaire to produce source light varying with each other and with time. The computerized device operates the luminaire such that each luminaire emits a source light, the source lights combining to form a combined light having selected characteristics. Each of the plurality of luminaires may be operable to emit light having increased spectral opponency, thereby reducing melatonin suppression. The source lights, when perceived directly, recreate a lighting scenario having varying lighting characteristics.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: June 3, 2014
    Assignee: Biological Illumination, LLC
    Inventors: Fredric S. Maxik, David E. Bartine, Robert R. Soler, Valerie A. Bastien, James Lynn Schellack
  • Patent number: 8718476
    Abstract: There is provided a method and apparatus for tuning an optical discriminator to the carrier frequency of an optical signal to allow superior reception of said signal. The carrier frequency of the signal is dithered during a test phase in order to provide information that allows a subsequent tuning phase to optimise the reception of the optical signal, as measured by a signal quality metric. The tuning phase may comprise adjustment of one or both of the carrier frequency and the optical discriminator.
    Type: Grant
    Filed: February 27, 2008
    Date of Patent: May 6, 2014
    Assignee: Xtera Communications, Inc.
    Inventors: Steven Webb, David Winterburn
  • Patent number: 8693872
    Abstract: A wavelength locking method, apparatus, and system are provided. The wavelength locking method includes modulating, by using scrambling signals with a same frequency and different phases, each one of a plurality of optical channel signals respectively; processing, by a combiner, a splitter, and a wavelength locker, the modulated optical signals, so as to acquire photoelectricity detector (PD) signals; performing phase discrimination on the PD signals to acquire wavelength information of the optical channels; determining different shift values corresponding to the different wavelength information; and adjusting wavelengths of the optical channels according to the corresponding shift values.
    Type: Grant
    Filed: April 29, 2011
    Date of Patent: April 8, 2014
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Shuangqi Wu, Fei Tang, Hongping Zhang
  • Patent number: 8687982
    Abstract: An OSNR measuring device n OSNR measuring device includes an input port to which a signal light is given; a wavelength filter which includes a variable passband, and selectively takes out an optical component corresponding to a signal optical wavelength to be measured from the signal light; a wavelength control circuit which controls the passband of the wavelength filter; a delay interferometer which branches a light output from the wavelength filter and delays one of the branched lights with respect to the other branched light and in which the branched lights are made to interfere with each other; a photodetector which detects a power of a delay interference light output; and an OSNR calculation circuit which calculates, based on a bandwidth of a passband of the wavelength filter and the power of the delay interference light, an optical signal to noise ratio of a signal optical wavelength to be measured.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: April 1, 2014
    Assignee: Fujitsu Limited
    Inventors: Kentaro Nakamura, Norifumi Shukunami
  • 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
  • Patent number: 8611750
    Abstract: An apparatus comprising a plurality of optical transmitters coupled to a fiber, a signal generator coupled to the optical transmitters and configured to provide a single pilot tone to the optical transmitters, and a processor positioned within a feedback loop between the fiber and the optical transmitters, the processor configured to adjust a wavelength for each of the optical transmitters to lock the wavelengths. An apparatus comprising at least one processor configured to implement a method comprising receiving an optical signal comprising a pilot tone, detecting an amplitude and a phase of the pilot tone, calculating a quadrature term using the amplitude and the phase, and wavelength locking the optical signal using the quadrature term.
    Type: Grant
    Filed: October 14, 2009
    Date of Patent: December 17, 2013
    Assignee: Futurewei Technologies, Inc.
    Inventors: Hongbing Lei, Xiao A. Shen, Yu Sheng Bai
  • Patent number: 8582984
    Abstract: A waveform controller includes a monitor configured to monitor a waveform of an output pulse obtained by the response of a responsive element to a driving signal supplied thereto and a driving waveform shaper configured to shape a waveform of the driving signal based on a monitoring result obtained by the monitor.
    Type: Grant
    Filed: November 18, 2009
    Date of Patent: November 12, 2013
    Assignee: Fujitsu Limited
    Inventor: Yutaka Kai
  • Patent number: 8571420
    Abstract: An apparatus for driving a wavelength-independent light source is provided. The apparatus includes a seed light signal generation unit configured to generate seed light signals with one or more wavelengths based on a wavelength identification signal, a wavelength light detection unit configured to detect the wavelength identification signal from the seed light signals, an extraction unit configured to extract wavelength information corresponding to the detected wavelength identification signal and extract a driving condition of a wavelength-independent light source corresponding to the extracted wavelength information, and a driving unit configured to drive the wavelength-independent light source according to the extracted driving condition.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: October 29, 2013
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seung-Hyun Cho, Han-Hyub Lee, Jie-Hyun Lee, Jong-Hoon Lee, Eun-Gu Lee, Eui-Suk Jung, Sang-Soo Lee
  • Patent number: 8565618
    Abstract: An optical transmitter may include a tunable signal source configured to emit a signal to an optical fiber system; a back scatter detector for measuring an amount of back scatter observed following injection of the signal to the optical fiber system; and control logic. The control logic may be configured to cause the tunable signal source to scan through a range of wavelengths. Measured amounts of back scatter are received for each of the wavelengths. A wavelength corresponding to a peak back scatter amount may be identified and the tunable signal source may be set based on the identified wavelength.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: October 22, 2013
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Tiejun J. Xia, Glenn A. Wellbrock
  • Patent number: 8559821
    Abstract: An apparatus comprising a laser transmitter having a first side and a second side, a filter coupled to the first side, a detector coupled to the second side, and a temperature controller coupled to the laser transmitter and the detector. Also disclosed is an apparatus comprising at least one processor configured to implement a method comprising receiving a photocurrent of a backward light from a laser, determining a wavelength shift offset between a wavelength of the output light and a filter transmission peak, and adjusting a temperature of the laser to substantially reduce the wavelength shift and align the wavelength of the output light with the filter transmission peak.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: October 15, 2013
    Assignee: Futurewei Technologies, Inc.
    Inventors: Yang Jing Wen, Jizhong Liu, Yu Sheng Bai
  • Patent number: 8503881
    Abstract: Method, apparatus and systems for a wavelength division multiplexing system operating at O-Band. The system includes a transmitter for wavelength division multiplexing digital O-band optical channels into a multiplexed optical signal, amplifying and transmitting the multiplexed optical signal, a fiber transmission span using constant intensity modulation and semiconductor optical amplification, and a receiver for receiving and amplifying the transmitted multiplexed optical signal and restoring the individual digital O-band optical signals. In an embodiment, the transmission span is a single mode fiber transmission span and in another embodiment includes an optical amplifier module coupled into the fiber transmission span. In another embodiment, the transmission span includes a length of O-band dispersion compensating fiber to reduce four-wave mixing. In another embodiment the system uses wavelength division multiplexing in combination with polarization interleaving.
    Type: Grant
    Filed: April 3, 2008
    Date of Patent: August 6, 2013
    Assignee: University of Central Florida Research Foundation, Inc.
    Inventor: Guifang Li
  • Publication number: 20130188958
    Abstract: A feedback light tuning device and the optical communication system and method using the same are provided. By tuning the feedback light, the mechanism can completely correct the mean-wavelength drift up to 30 nm or 19400 ppm. The mechanism can be applied to various harsh environments which cause the mean-wavelength drift, so as to achieve a required stable mean-wavelength for the light source and to increase the acceptable range of radiation dose.
    Type: Application
    Filed: July 3, 2012
    Publication date: July 25, 2013
    Applicant: NATIONAL TAIWAN UNIVERSITY
    Inventors: Tz Shiuan PENG, Lon Wang
  • Patent number: 8472805
    Abstract: Techniques, devices and systems for optical communications based on wavelength division multiplexing (WDM) that use tunable multi-wavelength laser transmitter modules.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: June 25, 2013
    Assignee: Google Inc.
    Inventors: Cedric F. Lam, Hong Liu
  • Patent number: 8447182
    Abstract: According to one embodiment, a system for transmitting an optical signal comprises a traffic distribution circuit configured to distribute traffic to a plurality of wavelength division multiplexer (WDM) modules. The system further comprises a first WDM module and a second WDM module. The first and second WDM modules each comprise a plurality of tunable optical transmitters, with each transmitter associated with a different wavelength band of a plurality of wavelength bands. Each transmitter in the first and second WDM modules is also tuned to transmit optical signals in channels included within the associated wavelength band of the transmitter. The first and second WDM modules each comprise a multiplexer configured to combine the optical signals transmitted from the plurality of transmitters into optical signals. The system further comprises a cyclic multiplexer configured to combine the optical signals from the first and second WDM modules into an optical output signal.
    Type: Grant
    Filed: September 30, 2010
    Date of Patent: May 21, 2013
    Assignee: Fujitsu Limited
    Inventors: Martin Bouda, Inwoong Kim, Takao Naito
  • Publication number: 20130084073
    Abstract: An apparatus comprising a plurality of optical transmitters and a wavelength locker shared by the plurality of optical transmitters. A periodic transmission filter used for wavelength locker operations is in a network communication path and shapes optical transmissions from the plurality of optical transmitters to a network. An apparatus comprising at least one processor configured to receive a pre-filter signal corresponding to part of an optical signal comprising a pilot tone and to receive a post-filter signal corresponding to a part of the optical signal that passes through a period transmission filter, wherein a filtered part of the optical signal is directed into a network. The processor is also configured to perform wavelength locking based on a quadrature detection technique that aligns an adiabatic logical one position of a modulated transmission signal with a spectral transmission peak of the period transmission filter.
    Type: Application
    Filed: September 29, 2011
    Publication date: April 4, 2013
    Applicant: FUTUREWEI TECHNOLOGIES, INC.
    Inventors: Xiao A. Shen, Tongqing Wang, Hongbing Lie, Yu Sheng Bai
  • Patent number: 8385743
    Abstract: Signal wavelengths ?1, ?2, ?3 of signal light components multiplexed at signal multiplexing sections 31, 41, 51 of multiplexing stations 3, 4, 5 installed on the input end side of an EDFA 2 on an optical transmission line 1 are set such that the wavelength-dependent noise figure of EDFA 2 successively decreases from the signal wavelength ?1 multiplexed at the signal multiplexing section 31 closest to the input end of EDFA 2 to ?2 and ?3. On the other hand, the transmission length of individual signal light component before being fed into the EDFA 2 is the shortest in the signal light component at ?1 and successively increases at ?2 and ?3. Thus, the order of magnitude of input signal light power is the same as the order of highness of noise figure in EDFA 2, whereby fluctuations in S/N ratio in the resulting amplified light are reduced.
    Type: Grant
    Filed: February 13, 2001
    Date of Patent: February 26, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Toshiaki Okuno, Masayuki Nishimura
  • Patent number: 8364045
    Abstract: An optical transmission device in which: a first cyclic filter with a fixed transmission wavelength characteristic and a second cyclic filter with a variable transmission wavelength characteristic are combined, and the transmission wavelength characteristic of the second cyclic filter is changed according to a target wavelength, to thereby control the relative phase relationship of the transmission wavelength characteristics of the first and second cyclic filters. Moreover a light source is controlled according to a monitored value of the transmittance of the second cyclic filter with respect to the control target light, to thereby match the wavelength of the control target light with the target wavelength. Consequently, it is possible, with a simple configuration using a combination of two cyclic filters, to variably control wavelength at arbitrary wavelength intervals at a high level of precision.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: January 29, 2013
    Assignee: Fujitsu Optical Components Limited
    Inventors: Tomohisa Ishikawa, Hiroshi Kuzukami
  • Patent number: 8340525
    Abstract: A method for stabilizing multi-channel optical signal wavelengths includes the following steps. A first detecting signal is stacked on a plurality of driving signals in sequence. A plurality of optical signals generated after being driven by the plurality of driving signals is combined into one optical total signal. A wavelength detection is performed on the optical total signal. A second detecting signal with a frequency band the same as that of the first detecting signal is extracted from the signals obtained after the wavelength detection. The wavelength of the optical signal in the corresponding channel among the multiple channels is controlled according to the second detecting signal. A device for stabilizing multi-channel optical signal wavelengths is also provided. Using the above method or device, the multi-channel optical signal wavelengths can be stabilized, which requires less elements, and has a simple circuit structure, a high integration level, and a low cost.
    Type: Grant
    Filed: April 29, 2009
    Date of Patent: December 25, 2012
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Yusheng Bai, Naisheng Zhang, Changgui Xiao
  • Patent number: 8331783
    Abstract: An optical communication system includes a first optical communication apparatus configured to insert a wavelength control signal in a main signal to produce a modified main signal; convert the modified main signal into a first optical signal; and transmit the first optical signal, and a second optical communication apparatus configured to receive the first optical signal; extract the wavelength control signal from the received first optical signal; determine a wavelength of a second optical signal based on the extracted wavelength control signal; and transmit the second optical signal to the first optical communication apparatus.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: December 11, 2012
    Assignee: NEC Corporation
    Inventors: Kazuhito Ikai, Hiroshi Nakaishi, Yasuhisa Kanda, Yoshitaka Nakao
  • Patent number: 8320758
    Abstract: A method for estimating optical power in an optical channel includes determining a tunable filter full-width, FWF, by measuring a response of the tunable filter to a known signal and mapping the response to frequency. A portion of an optical channel is coupled to an input of the tunable optical filter. A peak power response, PR, and a full width tunable filter response, FWR, to the optical channel are determined by measuring a response of the tunable filter to the optical channel and mapping the response to frequency. A signal power, PS, is then calculated from the peak power response, PR, and a ratio of the full width tunable filter response, FWR, to the tunable filter full-width, FWF.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: November 27, 2012
    Assignee: Aegis Lightwave, Inc.
    Inventor: Michael Cahill
  • Patent number: 8295704
    Abstract: A laser unit, usable in a network interface unit (NIU), that includes a laser adapted to generate an optical signal having a wavelength, a temperature control system for establishing a temperature of the laser and a controller functionally connected to the temperature control system for setting the temperature, the controller configured to automatically vary the temperature between a high temperature and a low temperature different than the high temperature. Also an NIU and a system of NIU's including the laser and an associated method of controlling the laser.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: October 23, 2012
    Assignee: CommScope, Inc. of North Carolina
    Inventor: Mark Vogel
  • Publication number: 20120251122
    Abstract: The invention relates to a method of operating a first optical network element (100), particularly an optical network unit, ONU, wherein said method comprises the following steps: performing a coarse tuning process (2100) of at least one transmission wavelength which is used by said first optical network element (100) for transmitting an optical signal to a second optical network element (200), particularly an optical line terminal, OLT, and performing a fine tuning process (2200) of said at least one transmission wavelength, wherein said fine tuning process (2200) is preferably performed after said coarse tuning process (2100).
    Type: Application
    Filed: February 21, 2012
    Publication date: October 4, 2012
    Applicant: ADVA AG OPTICAL NETWORKING
    Inventors: Klaus Grobe, Markus Roppelt
  • Patent number: 8275264
    Abstract: According to an aspect of an embodiment, an apparatus for controlling optical waveform, comprises: an input port for inputting a signal light having a modulating frequency and a signal light power; a pump light generator generating pulsed pump light having a frequency higher than the modulating frequency of the signal light and a pulsed pump light power; a nonlinear optical medium for transmitting the signal light from the input port and the pulsed pump light, the nonlinear optical medium having a gain of the signal light based on a nonlinear optical effect; and a power adjustor for adjusting a gain of the signal light saturates in the nonlinear optical medium by a nonlinear optical effect by adjusting at least one of the signal light power or the pulsed pump light power.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: September 25, 2012
    Assignee: Fujitsu Limited
    Inventor: Shigeki Watanabe
  • Patent number: 8254793
    Abstract: A tunable element of a tuning module is receptive to optical data channels of a multiplexed optical data signal, each optical data channel having a different respective wavelength. The tunable element is responsive to different stimuli such that multiple passbands of the tunable element are defined, each passband corresponding to a respective stimulus and including no more than one wavelength of the optical data channels. An optical detector communicates with the tunable element and is receptive to no more than one optical data channel from the tunable element at any given time, an output of the optical detector is an electrical data signal that corresponds to the optical data channel received by the optical detector from the tunable element. A controller communicates with the tunable element and tunes the tunable element from one optical data channel to the other by causing application of a corresponding stimulus to the tunable element.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: August 28, 2012
    Assignee: Finisar Corporation
    Inventors: Gayle L. Noble, Lucy G. Hosking, Luke Ekkizogloy, James L. Noble
  • Patent number: 8195052
    Abstract: An optical wavelength multiplexing system includes transmission-side and reception-side optical wavelength multiplexers, and terminal devices, which are connected to each other by optical fiber cables. Optical wavelength converters in the transmission-side optical wavelength multiplexers are connected to ports respectively. The optical wavelength converter converts an input optical signal into an arbitrary preset wavelength to generate a converted optical signal. The port has a predetermined wavelength preset therein. Each optical power level of input converted optical signals is compared with each optical power level of optical signals of respective wavelengths set in the ports. When a difference is detected in the comparison result, it is determined that an optical wavelength converter is incorrectly connected to the port.
    Type: Grant
    Filed: December 6, 2007
    Date of Patent: June 5, 2012
    Assignee: Fujitsu Limited
    Inventors: Makoto Ohtou, Akira Yamamoto, Tatsuo Nagayoshi, Katsumi Sugawa, Hideaki Sugiya
  • Patent number: 8190028
    Abstract: A signal treating apparatus for presenting an output signal representing an input signal over a signal range includes: (a) an input section receiving the input signal and presenting a first filtered signal limited to a first bandwidth at a first circuit locus; the input section presenting a second filtered signal limited to a second bandwidth at a second circuit locus; (b) an amplifying unit receiving the first filtered signal and presenting an increased gain signal at an amplifier output locus; (c) a detector coupled with the amplifier output locus and presenting third bandwidth-limited signal limited to a third bandwidth less than the first bandwidth at a third circuit locus; and (d) a combining section coupled with the second and third circuit loci and presenting a resulting signal related with the second filtered signal and the third filtered signal; said resultant signal being said output signal.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: May 29, 2012
    Assignee: The Boeing Company
    Inventor: James D. Franklin
  • Patent number: 8175427
    Abstract: Apparatus and methods for using a tunable optical source in safety curtain applications provide for enhanced operation of the safety curtain. In an embodiment, a safety curtain includes a transmit unit and a receive unit to operate as the safety curtain, where a single tunable light source generates different wavelengths of light and a single detector is used to detect the generated light.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: May 8, 2012
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Francis Lawrence Leard, Hassan R. Manjunath, James Edward Dogul
  • Patent number: 8139940
    Abstract: There is provided a wavelength division multiplexing transmission system and apparatuses used therein, in which a remote apparatus to be newly added to a station apparatus autonomously sets a wavelength to be used in the remote apparatus, thereby avoiding the need for presetting a wavelength to be used in the remote apparatus. The remote apparatus includes wavelength determining means that determines an available wavelength on the basis of an optical signal received from the station apparatus. The wavelength determining means may determine the wavelength of an unreceived optical signal as the available wavelength or may determine the wavelength of a received optical signal as the available wavelength, and may set that wavelength as a transmission and reception wavelength to be used in the remote apparatus.
    Type: Grant
    Filed: December 4, 2009
    Date of Patent: March 20, 2012
    Assignee: NEC Corporation
    Inventor: Shigekazu Harada
  • Patent number: RE45193
    Abstract: An apparatus and method for extracting an optical clock signal are provided. The apparatus includes a first reflection filter selecting and reflecting only a first frequency component in an input optical signal; a first Fabry-Perot laser diode matching the first frequency component reflected by the first reflection filter with a predetermined output mode and outputting the first frequency component in the predetermined output mode; a second Fabry-Perot laser diode selecting a second frequency component in an input optical signal that has not been reflected but has been transmitted by the first reflection filter, matching the second frequency component with a predetermined output mode, and outputting the second frequency component in the predetermined output mode; and a photodetector receiving the first frequency component from the first Fabry-Perot laser diode and the second frequency component from the second Fabry-Perot laser diode and beating them to extract a clock signal.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: October 14, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jaemyoung Lee, Je Soo Ko