Patents by Inventor Toshiki Tanaka

Toshiki Tanaka has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8073339
    Abstract: An optical modulation device including waveform shapers that waveform-shape input data signals in synchronism with a rising or falling timing based on comparison with a reference level of an input clock signal, a multi-level phase modulator that generates a multi-level-phase-modulated optical signal based on the data signals waveform-shaped by the plurality of waveform shapers, and outputs the generated optical signal, and a level ratio controller that varies a relative level ratio of the reference level to an amplitude level of the clock signal input to the waveform shapers, based on the optical signal output from the multi-level phase modulator.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: December 6, 2011
    Assignee: Fujitsu Limited
    Inventors: Masato Nishihara, Tomoo Takahara, Toshiki Tanaka
  • Publication number: 20110249971
    Abstract: A polarization fluctuation compensation device, when WDM light received by, for example, an optical reception device includes a polarization scrambled optical signal and a non-polarization scrambled optical signal, collects information related to whether optical signals having respective wavelengths are polarization scrambled, obtains a target value of control parameters which are different from each other, according to the speed of polarization fluctuations in the non-polarization scrambled optical signal based on the collected information, and performs reception processing of the non-polarization scrambled optical signal by using a control parameter set as the target value. As a result, an influence of fast polarization fluctuations generated resulting from an interaction between optical signals having respective wavelengths can be reliably compensated for, thereby enabling to realize excellent reception characteristics.
    Type: Application
    Filed: March 31, 2011
    Publication date: October 13, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Shoichiro Oda, Takeshi Hoshida, Toshiki Tanaka, Hiroyuki Irie, Hiroshi Nakamoto
  • Publication number: 20110222853
    Abstract: A polarized-wave-multiplexing optical transmitter including: an optical combiner generating a polarized-wave-multiplexed optical signal by polarized-wave-multiplexing a first optical modulation signal and a second optical modulation signal; an optical power fluctuation portion fluctuating optical power of the first optical modulation signal and the second optical modulation signal periodically; a total-optical-power detection portion detecting fluctuation amount of total optical power of the polarized-wave-multiplexed optical signal; and an optical power controller reducing an optical power difference between the first optical modulation signal and the second optical modulation signal based on detection result of the total-optical-power detection portion.
    Type: Application
    Filed: February 16, 2011
    Publication date: September 15, 2011
    Applicant: Fujitsu Limited
    Inventors: Toshiki TANAKA, Yuichi Akiyama, Masato Nishihara
  • Publication number: 20110032594
    Abstract: According to an aspect of an embodiment, an optical modulation device includes a Mach-Zehnder modulator and a controller. The Mach-Zehnder modulator is supplied a drive signal and a bias voltage. The Mach-Zehnder modulator modulates inputted light on the bases of the drive signal and the bias voltage. The drive signal selectively is superimposes a predetermined frequency signal. The bias voltage selectively is superimposes the predetermined frequency signal. The controller selects a superimposing target which is the drive signal or the bias voltage so as to change modulation formats.
    Type: Application
    Filed: July 9, 2010
    Publication date: February 10, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Toshiki Tanaka, Hideyuki Miyata, Yuichi Akiyama, Takeshi Hoshida
  • Publication number: 20110027213
    Abstract: Provided are an organopolysiloxane that exhibits good dispersion stability within not only organic oil agents but also cosmetic materials that contain a powder, and is able to produce a cosmetic material that exhibits excellent skin affinity, an organopolysiloxane that does not impart a sticky feeling, and exhibits excellent skin affinity and skin adhesion, and a cosmetic material including such an organopolysiloxane. The organopolysiloxane is represented by formula (1) below: in which R1 represents a hydrocarbon group such as an alkyl group, R2 represents a group represented by formula (3) or formula (4) below: in which either R4 represents a specific hydrocarbon group and R5 represents a hydrogen atom or a specific hydrocarbon group, or alternatively, at least one of R4 and R5 represents a hydroxyalkyl group, and A represents a group containing an organosilyl group or organosiloxane residue.
    Type: Application
    Filed: July 27, 2010
    Publication date: February 3, 2011
    Inventors: Masanao KAMEI, Toshiki Tanaka
  • Publication number: 20110026927
    Abstract: A transmission apparatus is provided. The transmission apparatus in a transmission system that performs dispersion compensation on a transmission line includes a receiver, an information collection unit and a chromatic dispersion providing unit. The receiver receives a wavelength division multiplexing optical signal for each wavelength from the transmission line. The information collection unit collects information regarding a reception method applied to each wavelength of the optical signal received by the receiver, as reception method information. The chromatic dispersion providing unit provides respective chromatic dispersion amounts different from each other to an optical signal received using a digital coherent reception method and an optical signal received using a reception method other than the digital coherent reception method, based on the information regarding a reception method collected by the information collection unit.
    Type: Application
    Filed: July 20, 2010
    Publication date: February 3, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Toshiki Tanaka, Takeshi Hoshida
  • Patent number: 7853147
    Abstract: The present invention provides an information processing system, comprising a plurality of calculation nodes with an optical transmitter, which individually outputs a plurality of optical signals each having a different wavelength, and an optical receiver, which individually receives a plurality of optical signals each having a different wavelength, an optical transmission path connecting a plurality of the calculation nodes to each other, and optical pathway switching unit, lying in the optical transmission path, for transmitting the optical signal to the specific calculation node in accordance with a wavelength of the optical signal output from one of the calculation nodes.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: December 14, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiki Tanaka, Yasuhiko Aoki, Hideyuki Miyata, Takao Naito, Kouichiro Amemiya
  • Publication number: 20100295489
    Abstract: There is provided a motor drive control apparatus that includes a resistor, which directly or indirectly detects a driving current supplied to a motor and generates a voltage corresponding to the driving current, converts, with an AD converter, the voltage corresponding to the motor driving current detected by the resistor into a numerical value, and reflects the motor driving current converted into the numerical value on driving control for the motor, wherein a plurality of the resistors is connected in series to form a resistor string, and voltage between arbitrary two points of the resistor string is AD-converted.
    Type: Application
    Filed: March 31, 2008
    Publication date: November 25, 2010
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Shuya Sano, Kiyonari Kawajiri, Toshiki Tanaka
  • Patent number: 7840141
    Abstract: The present invention is a miniaturized differential M phase-shift modulator (M=2n: n is 2 or more) in which a plurality of Mach-Zehnder type light modulators each adapted to output a DPSK-modulated signal light by applying a driving voltage signal are arranged in parallel and that comprises a multiplexing waveguide adapted to output a DMPSK-modulated light by multiplexing outputs of the plurality of the Mach-Zehnder type light modulators, wherein a phase-shift voltage to produce a phase shift difference of substantially 2?/M for a plurality of the signal lights multiplexed by the multiplexing waveguide is applied to the plurality of the Mach-Zehnder type light modulators together with the driving voltage signal.
    Type: Grant
    Filed: August 27, 2007
    Date of Patent: November 23, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiki Tanaka, Hideyuki Miyata
  • Patent number: 7813640
    Abstract: An optical connection switching according to the present invention comprises an optical connection switching facility capable of making a connection between any one of optical input ports and any one of optical output ports, one or more optical transmitting/receiving units connected to a portion of the optical input/output ports, and management control units for controlling the optical connection switching facility to make a connection between the optical input/output port connected to the optical transmitting/receiving unit and the optical input/output port connected to equipment for acquiring and managing information on the equipment by making a communication with the equipment through the use of the optical transmitting/receiving unit. This enables acquiring the information on the equipment having an optical communication interface to be optically connected, thereby automating the connection management of the equipment.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: October 12, 2010
    Assignee: Fujitsu Limited
    Inventors: Kouichirou Amemiya, Takao Naito, Toru Katagiri, Toshiki Tanaka
  • Patent number: 7771709
    Abstract: An alternating copolymer comprising a repeating unit of ?,?-organohydrogensiloxane residue (A) and a repeating unit of a glycerol derivative residue (B) having 1 to 11 hydroxyl groups, the copolymer having the number of a repeating unit (AB) of from 2 to 100.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: August 10, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Tetsuo Nakanishi, Toshiki Tanaka, Kiyomi Tachibana
  • Patent number: 7773283
    Abstract: According to an aspect of an embodiment, an optical modulation device includes a Mach-Zehnder modulator and a controller. The Mach-Zehnder modulator is supplied a drive signal and a bias voltage. The Mach-Zehnder modulator modulates inputted light on the bases of the drive signal and the bias voltage. The drive signal selectively is superimposes a predetermined frequency signal. The bias voltage selectively is superimposes the predetermined frequency signal. The controller selects a superimposing target which is the drive signal or the bias voltage so as to change modulation formats.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: August 10, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiki Tanaka, Hideyuki Miyata, Yuichi Akiyama, Takeshi Hoshida
  • Patent number: 7734175
    Abstract: An optical wiring switching unit includes a first connection interface. A packet switch includes a second connection interface. A resource includes a third connection interface, and is formed with at least one of a server and a storage device. A control device controls the optical wiring switching unit to perform a switching of connection between the connection interfaces. The packet switch and the resource are connected to the optical wiring switching unit via the connection interfaces. A network is configured by connecting the packet switch and the resource with a control of the optical wiring switching unit.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: June 8, 2010
    Assignee: Fujitsu Limited
    Inventors: Kouichirou Amemiya, Toshiyuki Shibuya, Tsunehisa Doi, Toshiki Tanaka, Hideyuki Miyata, Yasutaka Taniuchi
  • Patent number: 7715709
    Abstract: The optical switch, having a plurality of ports capable of switching optical signal routes in a network in the form of light, includes a detection means for detecting information in regard to the transmission condition of an optical signal passing through each port; and a control means for exchanging the transmission condition information between each switch and controlling the ports, so as to select one route from among a plurality of routes transmitting the optical signal based on the difference of transmission condition information between the relevant switches. The transmission condition information is the power of the optical signal. When the difference between each switch exists, or when at least one switch intervenes in the middle of the transmission route, by selecting a transmission route which minimizes accumulated differences among the switches, configuring a tree structure conventionally performed through manual operation can be set automatically in an optical network system.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: May 11, 2010
    Assignee: Fujitsu Limited
    Inventors: Kouichirou Amemiya, Takao Naito, Toshiki Tanaka
  • Publication number: 20100067914
    Abstract: The polarization multiplexed light transmitter takes out a part of a polarization multiplexed light to be transmitted as a monitor light; makes orthogonal polarization components contained in the monitor light to interfere with each other, to generate a polarization interfering light; converts the polarization interfering light into an electric signal; measures the power of an alternate current component contained in the electric signal after eliminating a direct current component thereof; and feedback controls delay amount varying sections so that an inter-polarized channel delay time judged based on a change in the measured power reaches a predetermined value. Thus, the delay time between the orthogonal polarization components in the polarization multiplexed light can be varied flexibly at a high speed with a simple configuration, and thus, it becomes possible to suppress transmission characteristics degradation of the polarization multiplexed light due to a change in system state.
    Type: Application
    Filed: September 4, 2009
    Publication date: March 18, 2010
    Applicant: FUJITSU LIMITED
    Inventors: Toshiki Tanaka, Yuichi Akiyama, Masahiro Yuki, Hideyuki Miyata
  • Patent number: 7668465
    Abstract: An optical transmission system that alleviates waveform distortions due to nonlinear effects in fibers. A transmitter sends WDM signals to a receiver over a dispersion-managed optical transmission line with in-line optical repeaters. The transmission line is divided into a plurality of dispersion compensation intervals each composed of a main segment and a compensation segment. Chromatic dispersion is managed such that the dispersion compensation intervals have a non-zero net dispersion at every boundary point between them, or such that the number of zero-dispersion boundary points is reduced. The main segment is a series of repeater sections with negative dispersion, while the compensation segment is a single repeater section with positive dispersion.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: February 23, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiki Tanaka, Takao Naito
  • Patent number: 7635512
    Abstract: For accomplishing the subjects, the invention provides a nickel electrode material for use in a nickel electrode, wherein the positive-electrode material constituting the electrode material comprises: positive active material particles which comprise as the main component either a nickel hydroxide or a solid solution in a nickel hydroxide of one or more other elements and in which part of the nickel hydroxide has been oxidized; and a coating layer formed on the surface of the positive active material particles and comprising as the main component a high-order cobalt compound in which the cobalt has an oxidation number larger than 2, the average oxidation number of the nickel in the positive active material particles and the cobalt in the coating layer being from 2.04 to 2.40, and the positive-electrode material having a tap density of 2.0 g/cm3 or higher.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: December 22, 2009
    Assignee: Yuasa Corporation
    Inventors: Seijiro Ochiai, Mitsuhiro Kodama, Kengo Furukawa, Toshiki Tanaka, Minoru Kuzuhara, Masaharu Watada, Masahiko Oshitani
  • Publication number: 20090226165
    Abstract: An apparatus includes an oscillator circuit configured to generate a certain oscillation signal, an adder configured to add the oscillation signal to the tap coefficient of any of one or more taps of the transversal filter, a signal-quality measurer configured to measure a signal quality of a signal output from the transversal filter, and a tap-coefficient adjuster configured to control the value of the tap coefficient so that an optimal amount of shift in the signal quality of the output signal is achieved when the oscillation signal is added to the tap coefficient.
    Type: Application
    Filed: March 4, 2009
    Publication date: September 10, 2009
    Applicant: Fujitsu Limited
    Inventors: Toshiki Tanaka, Yuichi Akiyama
  • Patent number: 7577361
    Abstract: In the optical network system, light input to any of the optical input ports of the optical coupler is converted into light at another wavelength via a variable-wavelength optical receiver and an optical sender, and is then reinput to the optical coupler. This arrangement makes it possible to realize a full-mesh optical network system with a simple construction at low costs.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: August 18, 2009
    Assignee: Fujitsu Limited
    Inventors: Toshiki Tanaka, Takao Naito
  • Publication number: 20090142075
    Abstract: According to an aspect of an embodiment, a DQPSK optical receiver, comprising: a first LPF connected to a line branching off from between a first optical-electrical converter and a first data recovery circuit; a second LPF connected to a line branching off from between a second optical-electrical converter and a second data recovery circuit; a first LIA for amplifying a signal output from the first LPF and also limiting an amplitude of an output signal thereof; a second LIA for amplifying a signal output from the second LPF and also limiting an amplitude of an output signal thereof; a first mixer for multiplying the output signal from the first LIA by a signal output from the second LPF; and a second mixer for multiplying the output signal from the second LIA by a signal output from the first LPF.
    Type: Application
    Filed: September 4, 2008
    Publication date: June 4, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Yuichi AKIYAMA, Toshiki TANAKA