Patents by Inventor Tetsuya Miyazaki

Tetsuya Miyazaki 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: 7308211
    Abstract: An optical receiver including an optical divider to divide a signal light from an optical transmission line into two portions, a first and a second dispersion compensators, each dispersion compensator having variable dispersion compensation to compensate chromatic dispersions of each of the two portions of signal light output from the optical divider, and a data demodulator to demodulate a data carried by a signal light output from the first dispersion compensator. The optical receiver further includes an optical autocorrelator to operate on a signal light output from the second dispersion compensator and a controller to control the second dispersion compensator to increase autocorrelation of the optical autocorrelator, and to control the first dispersion compensator according to the result of said controlling the second dispersion compensator.
    Type: Grant
    Filed: December 2, 2003
    Date of Patent: December 11, 2007
    Assignee: Communications Research Laboratory, Independent Administrative Institution
    Inventor: Tetsuya Miyazaki
  • Patent number: 7293843
    Abstract: A braking system for a vehicle, including a braking device which puts brake on a vehicle; an operating device which includes an operating member that is operated by a driver of the vehicle in a braking force increasing direction, that is, an operating direction in which a braking force of the braking device is increased or in a braking force decreasing direction, that is, an operating direction in which the braking force of the braking device is decreased; and a control device which decides a target control value for controlling the braking device based on an operation state amount of the operating member and which controls the braking device based on the decided target control value, wherein the control device includes an operating direction-dependant target control value deciding portion which sets an increasing direction target control value that is the target control value when the operating member is operated in the braking force increasing direction, and a decreasing direction target control value that
    Type: Grant
    Filed: April 12, 2004
    Date of Patent: November 13, 2007
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Tetsuya Miyazaki
  • Publication number: 20070216222
    Abstract: A brake controller is provided, having a braking force application mechanism that presses a friction member against a braked member so as to apply a braking force to a wheel of a vehicle; and a control unit that calculates an index indicating the difference between an estimated braking effectiveness and an actual braking effectiveness, and calculates a correction amount using the index, determines that the index is inaccurate. The control unit further limits the change in the correction amount calculated using the index, if it is determined that the index is inaccurate, and corrects a target value, which is set to control a pressing force of the friction member, based on the correction amount to reduce a variation in a braking effectiveness of the vehicle.
    Type: Application
    Filed: February 22, 2007
    Publication date: September 20, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tetsuya Miyazaki, Yoshiaki Irie, Rio Suda
  • Publication number: 20070210647
    Abstract: A brake controller is provided that includes a braking force application mechanism that presses a friction member against a braked member so as to apply a braking force to a wheel of a vehicle; and a control unit. The control unit calculates an index, which indicates a difference between an expected braking effectiveness and an actual braking effectiveness, corrects a target value, which is set to control a pressing force of the friction member, in accordance with the index to reduce a variation in a braking effectiveness of the vehicle. The control unit further sets a variation range in accordance with a factor that causes the difference. The variation range limits a variation in a correction amount to correct the target value.
    Type: Application
    Filed: February 14, 2007
    Publication date: September 13, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tetsuya Miyazaki, Yoshiaki Irie, Rio Suda
  • Publication number: 20070194623
    Abstract: A brake control apparatus comprises: a braking force applying mechanism that brakes a wheel by pressing a friction member upon supply of a working fluid; and a control portion that computes a target value set for controlling the pressure of the working fluid by utilizing a detected temperature of the friction member so as to restrain fluctuations of the effect of the brake caused by temperature changes of the friction member. The control portion restricts the utilization of the detected temperature in the computation of the target value in case a decline of the detection accuracy of the friction member temperature is predicted to restrain the influence of the decline of the estimation accuracy of the friction member temperature on the braking force control.
    Type: Application
    Filed: January 24, 2007
    Publication date: August 23, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Tetsuya MIYAZAKI
  • Patent number: 7260331
    Abstract: To demultiplex a low-speed optical pulse signal from a high-speed optical pulse signal, an optical clock generator generates an optical clock of a control wavelength ?p at a predetermined frequency out of a pulse signal light of a signal wavelength ?s. On one side of a saturable absorber, an optical band reflection mirror is disposed to reflect a light of the signal wavelength ?s and to transmit a light of the control wavelength ?p. A pulse signal light of the signal wavelength ?s reciprocates in the saturable absorber. An optical pulse of the pulse signal light of the signal wavelength ?s enters the saturable absorber almost simultaneously with different optical pulses of the optical clock on the ways of going and returning. The saturable absorber has a transmission factor relative to the signal wavelength ?s. The transmission factor varies as the saturable absorber absorbs a light of the control wavelength ?p.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: August 21, 2007
    Assignee: National Institute of Information and Communications Technology, Incorporated Administrative Agency
    Inventor: Tetsuya Miyazaki
  • Publication number: 20070159001
    Abstract: In order to achieve a good brake feeling, a brake control system includes a master cylinder which discharges pressurized operating fluid according to an operating amount of a brake operating member by a driver, a stroke simulator which is connected to the master cylinder and creates a reaction force with respect to that operation according to the operating amount of the brake operating member, and a control portion which calculates a target deceleration using hydraulic pressure in the stroke simulator. The brake control system is also provided with a master cylinder pressure sensor that measures the hydraulic pressure in the master cylinder. The control portion may also calculate the target deceleration using an estimated value of the hydraulic pressure in the stroke simulator calculated based on the measured value from the master cylinder pressure sensor.
    Type: Application
    Filed: November 30, 2006
    Publication date: July 12, 2007
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Tetsuya MIYAZAKI, Yoshiaki Irie, Rio Suda
  • Publication number: 20070025737
    Abstract: An optical transmitter generates a transmission signal having a frame as a unit, the frame including a single optical pilot signal with a constant optical phase and a plurality of phase-modulated optical data signals, and outputs the transmission signal into a transmission line. In a receiver, a splitter splits the optical signal input from the transmission line. On a second arm of a Mach-Zehnder interferometer, an optical gate transmits the optical pilot signal and a duplicator duplicates the optical pilot signal output from the optical gate at predetermined time intervals. A balanced optical receiver converts the interfered optical signal output from the interferometer into an electrical signal. A gate and a discriminator extract the data from the electrical signal output from the receiver.
    Type: Application
    Filed: July 6, 2006
    Publication date: February 1, 2007
    Inventors: Yukiyoshi Kamio, Tetsuya Miyazaki
  • Publication number: 20070009264
    Abstract: An optical transmitter generates a transmission signal having a frame as a unit, the frame including a signal pilot signal with fixed amplitude and phase and two data bits to output the generated signal into a transmission line. In a receiver, a splitter splits the signal light from the transmission line. An optical delay delays the signal light for a 1-bit period. A first combiner combines the signal light from the transmission line and the output signal light from the optical delay. A photodetector converts the combined light into an electrical signal. A 3-bit optical delay, a second combiner, a BPF, and an oscillator generate a frame-timing signal. A gate separates a data from the output from the photodetector under the control of a gate control unit. A binary discriminator binary-discriminates the output signal from the gate.
    Type: Application
    Filed: July 5, 2006
    Publication date: January 11, 2007
    Inventors: Yukiyoshi Kamio, Tetsuya Miyazaki
  • Publication number: 20060158032
    Abstract: An operation-characteristic obtaining apparatus including an operation-characteristic obtaining portion which obtains, as an operation characteristic of an electromagnetic control valve which includes a coil and which is opened and closed according to at least a relationship between (a) an acting force corresponding to a difference of respective pressures of a working liquid on either side of the electromagnetic control valve and (b) an electromagnetic drive force corresponding to an electric current supplied to the coil, a relationship between (c) a valve switching current as an electric current that is supplied to the coil of the electromagnetic control valve at a time when the electromagnetic control valve is switched between a closed state thereof and an opened state thereof and (d) a difference at the time of the respective pressures on either side of the electromagnetic control valve; and a leakage detecting portion which detects, when the operation-characteristic obtaining portion obtains the operation
    Type: Application
    Filed: January 3, 2006
    Publication date: July 20, 2006
    Inventors: Tetsuya Miyazaki, Masaaki Komazawa, Yoshito Tanaka
  • Patent number: 6957870
    Abstract: A braking pressure control apparatus including a first pressure source including a power-operated pressurizing device, a second pressure source operable by a manually operable brake operating member to pressurize a fluid to a pressure higher than a level corresponding to the operating force of the brake operating member, a switching device for selectively placing the braking system in a first state in which a brake cylinder is operated with the fluid pressurized by the first pressure source and a second state in which the brake cylinder is operated with the fluid pressurized by the second pressure source, and a change restricting device operable upon a switching between the first and second states, to restrict a change of the operating state of the brake operating member and a change of the brake cylinder pressure, which change take place due to the switching, or a switching control device for controlling the switching device on the basis of the running condition of a vehicle whose wheel is braked by the brak
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: October 25, 2005
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kazunori Kagawa, Kimihiro Matsuki, Tetsuya Miyazaki, Fumiaki Kawahata, Akihiro Otomo, Eiji Nakamura
  • Publication number: 20050152698
    Abstract: According the invention, a multiplexed light composed of a signal light of a signal wavelength, and a first route control light of a first route control wavelength different from the signal wavelength or a second route control light of a second route control wavelength different from the signal light and the first route control wavelength is incident to a demultiplexer. The demultiplexer demultiplexes the signal light of the signal wavelength, the first route control light, and the second route control light from the multiplexed light. An interferometer optical switch outputs the signal light from first output port according to the first route control light, and outputs the signal light from second output port according to the second route control light.
    Type: Application
    Filed: December 28, 2004
    Publication date: July 14, 2005
    Inventor: Tetsuya Miyazaki
  • Publication number: 20050117915
    Abstract: An optical transmitter splits a linear polarization optical carrier into a TE wave and a TM wave. One of the TE wave and the TM wave is phase-modulated with a transmission data so as to generate a phase-modulated signal. The phase-modulated signal and the other one of the TE wave and the TM wave are coupled with a linear polarization and output into an optical transmission line. An optical receiver splits a light input from the optical transmission line into the TE wave and the TM wave. The TM wave or TE wave is converted into the TE wave or TM wave to interfere with the TE wave or TM wave. The interfered signal light is converted into an electric signal for restoration of the data.
    Type: Application
    Filed: November 30, 2004
    Publication date: June 2, 2005
    Inventor: Tetsuya Miyazaki
  • Publication number: 20050111854
    Abstract: An optical multilevel-coded signal transmission system transmits information from an optical transmitter to an optical receiver through an optical transmission line using optical intensity and optical phase separately. The optical transmitter includes an inverted RZ signal light generator to generate an inverted RZ signal light intensity-modulated with a first data, and an optical phase modulator to phase-modulate the inverted RZ signal light according to a second data. The optical receiver includes a splitter to split a light input from the optical transmission line into first and second portions, an inverter to invert the first portion from the splitter, a first detector to detect the first data in the first portion inverted by the inverter, a converter to convert a phase-modulated signal included in the second portion from the splitter into an optical intensity-modulated signal, and a second detector to detect the second data in the optical intensity-modulated signal from the converter.
    Type: Application
    Filed: September 30, 2004
    Publication date: May 26, 2005
    Inventor: Tetsuya Miyazaki
  • Publication number: 20050047452
    Abstract: To demultiplex a low-speed optical pulse signal from a high-speed optical pulse signal, an optical clock generator generates an optical clock of a control wavelength ?p at a predetermined frequency out of a pulse signal light of a signal wavelength ?s. On one side of a saturable absorber, an optical band reflection mirror is disposed to reflect a light of the signal wavelength ?s and to transmit a light of the control wavelength ?p. A pulse signal light of the signal wavelength ?s reciprocates in the saturable absorber. An optical pulse of the pulse signal light of the signal wavelength ?s enters the saturable absorber almost simultaneously with different optical pulses of the optical clock on the ways of going and returning. The saturable absorber has a transmission factor relative to the signal wavelength ?s. The transmission factor varies as the saturable absorber absorbs a light of the control wavelength ?p.
    Type: Application
    Filed: August 26, 2004
    Publication date: March 3, 2005
    Inventor: Tetsuya Miyazaki
  • Publication number: 20050047788
    Abstract: In an optical pulse demultiplexer according to the invention, an optical splitter splits an input pulse signal light having a signal wavelength into a firs portion and a second portion. An optical clock generator generates an optical clock having a clock wavelength at a predetermined frequency corresponding to 1/n (n is integer not less than 2) of a bit rate of the input pulse signal light out of the first portion of the output lights from the optical splitter. The clock wavelength is different from the signal wavelength. A saturable absorption optical element, to which the optical clock generated by the optical clock generator and the second portion enter, separates a channel component corresponding to the predetermined frequency out of the second according to the optical clock. An optical filter extracts an optical component of the signal wavelength out of the light output from the saturable absorption optical element.
    Type: Application
    Filed: August 11, 2004
    Publication date: March 3, 2005
    Inventor: Tetsuya Miyazaki
  • Publication number: 20050047791
    Abstract: An optical transmitter transmits an OTDM signal light on which a spectrum component of a predetermined frequency is superimposed into an optical transmission line. A photodetector in an optical receiver converts the OTDM signal light output from the optical transmission line into an electrical signal. An electric bandpass filter extracts a component having the predetermined frequency out of the output from the photodetector. An RF power monitor measures power of the predetermined frequency component out of the output from the filter. A controller controls first an amount of dispersion compensation of a chromatic dispersion compensator so that the power of the predetermined frequency component becomes lower, and thereafter a dispersion slope of the chromatic dispersion compensator so that the power of the predetermined frequency component becomes lower.
    Type: Application
    Filed: August 11, 2004
    Publication date: March 3, 2005
    Inventor: Tetsuya Miyazaki
  • Publication number: 20040222695
    Abstract: A braking system for a vehicle, including a braking device which puts brake on a vehicle; an operating device which includes an operating member that is operated by a driver of the vehicle in a braking force increasing direction, that is, an operating direction in which a braking force of the braking device is increased or in a braking force decreasing direction, that is, an operating direction in which the braking force of the braking device is decreased; and a control device which decides a target control value for controlling the braking device based on an operation state amount of the operating member and which controls the braking device based on the decided target control value, wherein the control device includes an operating direction-dependant target control value deciding portion which sets an increasing direction target control value that is the target control value when the operating member is operated in the braking force increasing direction, and a decreasing direction target control value that
    Type: Application
    Filed: April 12, 2004
    Publication date: November 11, 2004
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Tetsuya Miyazaki
  • Patent number: 6801720
    Abstract: The present invention has an object to obtain an optical signal quality supervisory device that supervises the quality of an optical signal simply, efficiently and with high accuracy without inviting an increase in cost, an increase in circuit scale and increase in power consumption. The bit rate of the optical supervisory channel is made lower than the bit rate of the optical main channel that is transmitted over an optical communication system, but the reception electric band width of a receiver that receives the optical supervisory channel is made equal to or wider than the reception electric band width of a receiver that receives the optical main channel. Also, the optical supervisory channel is made up of an SOH (section over head) frame to detect an error of the BIP (bit interleaved parity) byte of SOH, thereby supervising the quality of the optical communication system, in particular, the light wave network.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: October 5, 2004
    Assignees: Mitsubishi Denki Kabushiki Kaisha, KDD Corporation
    Inventors: Takashi Mizuochi, Yojiro Osaki, Aritomo Uemura, Hiroshi Ichibangase, Kiwami Matsushita, Tadayoshi Kitayama, Shu Yamamoto, Tetsuya Miyazaki, Takatomi Kabashima, Naoki Kobayashi
  • Publication number: 20040179849
    Abstract: An optical receiver comprises a dispersion compensator (32) having variable amount of dispersion compensation to compensate chromatic dispersion of a signal light input from an optical transmission line (20), a selfcorrelator (44) to operate selfcorrelation of a signal light output from the dispersion compensator (32), and a controller (46) to control the dispersion compensator (32) to make the selfcorrelation of the optical selfcorrelator (44) larger.
    Type: Application
    Filed: December 2, 2003
    Publication date: September 16, 2004
    Inventor: Tetsuya Miyazaki