Patents by Inventor Shogo Yamanaka

Shogo Yamanaka 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: 12057127
    Abstract: A microphone unit includes: an audio data acquisition unit that acquires speech as audio data; an audio data registration unit that registers verification audio data obtained by extracting a feature point from the audio data; an evaluation audio data acquisition unit that acquires speech that is input to a first microphone as evaluation audio data; a verification unit that verifies whether or not a speaker who uttered speech that is based on the evaluation audio data is a speaker who uttered speech that is based on the verification audio data, based on the verification audio data and a feature point extracted from the evaluation audio data; and a verification result output unit that outputs a result of verification performed by the verification unit.
    Type: Grant
    Filed: June 9, 2020
    Date of Patent: August 6, 2024
    Assignee: HOSIDEN CORPORATION
    Inventors: Yoshifumi Yamanaka, Shogo Kubota
  • Patent number: 11736202
    Abstract: There are provided an evaluation method and an evaluation device for an optical receiver capable of evaluating only a phase error between optical 90-degree hybrids with high accuracy even when there is a skew between channels in the optical receiver. In the evaluation method and the evaluation device for the optical receiver including optical 90-degree hybrids, a phase error between the optical 90-degree hybrids is calculated by calculation of decomposing a transfer function of the optical receiver into a product of matrixes to evaluate the optical receiver.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: August 22, 2023
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shogo Yamanaka, Masanori Nakamura, Asuka Matsushita
  • Patent number: 11646800
    Abstract: An optical transmitter includes quadrature modulators and light receiving elements to which inverted output light of output light from the quadrature modulators is input, the quadrature modulators including parent Mach-Zehnder modulators in respective paths of a first pair of paths into which carrier light from a light source is split, the parent Mach-Zehnder modulators including child Mach-Zehnder modulators including first phase modulation units, and second phase modulation units.
    Type: Grant
    Filed: January 15, 2020
    Date of Patent: May 9, 2023
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shogo Yamanaka, Yusuke Nasu, Hiroto Kawakami
  • Publication number: 20230069120
    Abstract: Provided is a high-speed optical transmission-reception apparatus including a digital-signal processing circuit and optical modulation and optical reception modules, in which a flexible printed circuit is used as a high-frequency interface for the optical modulation and optical reception modules, a mechanism for connecting the high-frequency line pattern to the flexible printed circuit is provided on a package substrate of the digital-signal processing circuit, and the package substrate and the optical modulation and optical reception modules are connected by the flexible printed circuit.
    Type: Application
    Filed: February 28, 2020
    Publication date: March 2, 2023
    Inventors: Yoshihiro Ogiso, Hiromasa Tanobe, Shogo Yamanaka, Josuke Ozaki, Mitsuteru Ishikawa
  • Patent number: 11509396
    Abstract: Provided is a polarization multiplexing optical transmitting and receiving circuit that compensates for transmission side PDL so as to suppress a reduction in transmission power and makes a branching ratio of light from a light source variable between a transmission side and a receiving side according to a system to be used.
    Type: Grant
    Filed: March 19, 2020
    Date of Patent: November 22, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yusuke Nasu, Shogo Yamanaka, Yuichiro Ikuma
  • Patent number: 11493776
    Abstract: A polarization multiplex optical transmitter circuit can provide compensation for the transmission PDL while reducing decrease in transmission power. The polarization multiplex optical transmitter circuit includes a beam divider circuit configured to divide light outputted from a light source, optical phase shifters provided in at least one of two waveguides connected to output terminals of the beam divider circuit, a light wave synthesizer circuit connected to the two waveguides, first and second optical transmitters coupled to two output terminals of the light wave synthesizer circuit, a polarization multiplexer configured to synthesize two output polarized waves from the first and second optical transmitters, and a polarization rotator provided between the first and second optical transmitters and the polarization multiplexer and coupled to at least one of the first and second optical transmitters.
    Type: Grant
    Filed: December 24, 2019
    Date of Patent: November 8, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yusuke Nasu, Manabu Oguma, Shogo Yamanaka, Makoto Jizodo
  • Publication number: 20220140913
    Abstract: There are provided an evaluation method and an evaluation device for an optical receiver capable of evaluating only a phase error between optical 90-degree hybrids with high accuracy even when there is a skew between channels in the optical receiver. In the evaluation method and the evaluation device for the optical receiver including optical 90-degree hybrids, a phase error between the optical 90-degree hybrids is calculated by calculation of decomposing a transfer function of the optical receiver into a product of matrixes to evaluate the optical receiver.
    Type: Application
    Filed: March 6, 2020
    Publication date: May 5, 2022
    Inventors: Shogo Yamanaka, Masanori Nakamura, Asuka Matsushita
  • Publication number: 20220116116
    Abstract: An optical transmitter includes quadrature modulators and light receiving elements to which inverted output light of output light from the quadrature modulators is input, the quadrature modulators including parent Mach-Zehnder modulators in respective paths of a first pair of paths into which carrier light from a light source is split, the parent Mach-Zehnder modulators including child Mach-Zehnder modulators including first phase modulation units, and second phase modulation units.
    Type: Application
    Filed: January 15, 2020
    Publication date: April 14, 2022
    Inventors: Shogo Yamanaka, Yusuke Nasu, Hiroto Kawakami
  • Publication number: 20220066227
    Abstract: A polarization multiplex optical transmitter circuit can provide compensation for the transmission PDL while reducing decrease in transmission power. The polarization multiplex optical transmitter circuit includes a beam divider circuit configured to divide light outputted from a light source, optical phase shifters provided in at least one of two waveguides connected to output terminals of the beam divider circuit, a light wave synthesizer circuit connected to the two waveguides, first and second optical transmitters coupled to two output terminals of the light wave synthesizer circuit, a polarization multiplexer configured to synthesize two output polarized waves from the first and second optical transmitters, and a polarization rotator provided between the first and second optical transmitters and the polarization multiplexer and coupled to at least one of the first and second optical transmitters.
    Type: Application
    Filed: December 24, 2019
    Publication date: March 3, 2022
    Inventors: Yusuke Nasu, Manabu Oguma, Shogo Yamanaka, Makoto Jizodo
  • Publication number: 20220045764
    Abstract: Provided is a polarization multiplexing optical transmitting and receiving circuit that compensates for transmission side PDL so as to suppress a reduction in transmission power and makes a branching ratio of light from a light source variable between a transmission side and a receiving side according to a system to be used.
    Type: Application
    Filed: March 19, 2020
    Publication date: February 10, 2022
    Inventors: Yusuke Nasu, Shogo Yamanaka, Yuichiro Ikuma
  • Publication number: 20210297159
    Abstract: It is an object of the present invention to achieve an optical transceiver and a method for controlling the optical transceiver capable of reducing transmission light intensity to a sufficiently low value, when a transmission light blocking function has been started, without stopping the function of an optical receiver or without providing any variable optical attenuator. In the optical transceiver provided with a quadrature modulator in which parent and child Mach-Zehnder modulators are nested, when blocking a transmission light signal, a bias voltage of the phase modulator unit of the Mach-Zehnder modulator is adjusted so that phase differences at respective arms of the parent and child Mach-Zehnder modulators become 180 degrees.
    Type: Application
    Filed: July 12, 2019
    Publication date: September 23, 2021
    Inventors: Shogo Yamanaka, Yusuke Nasu
  • Patent number: 10637569
    Abstract: A method estimating transmission characteristics of an optical transmitter of a transmission unit and an optical receiver of a reception unit, including: estimating a temporary transfer or inverse transfer function of the optical receiver; estimating a transfer or inverse transfer function of the optical transmitter from first data acquired by the reception unit when a first known signal is transmitted from the transmission unit, and the estimated temporary transfer or inverse transfer function of the optical receiver, a difference between the first known signal and an original first known signal is minimized; and estimating a transfer or inverse transfer function of the optical receiver from second data acquired by the reception unit when a second known signal is transmitted from the transmission unit, and the estimated transfer or inverse transfer function of the optical transmitter, a difference between the second known signal and an original second known signal is minimized.
    Type: Grant
    Filed: November 8, 2017
    Date of Patent: April 28, 2020
    Assignees: NTT ELECTRONICS CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro Yamagishi, Tetsuya Maruyama, Masanori Nakamura, Asuka Matsushita, Shogo Yamanaka
  • Publication number: 20200036440
    Abstract: A method estimating transmission characteristics of an optical transmitter of a transmission unit and an optical receiver of a reception unit, including: estimating a temporary transfer or inverse transfer function of the optical receiver; estimating a transfer or inverse transfer function of the optical transmitter from first data acquired by the reception unit when a first known signal is transmitted from the transmission unit, and the estimated temporary transfer or inverse transfer function of the optical receiver, a difference between the first known signal and an original first known signal is minimized; and estimating a transfer or inverse transfer function of the optical receiver from second data acquired by the reception unit when a second known signal is transmitted from the transmission unit, and the estimated transfer or inverse transfer function of the optical transmitter, a difference between the second known signal and an original second known signal is minimized.
    Type: Application
    Filed: November 8, 2017
    Publication date: January 30, 2020
    Applicants: NTT Electronics Corporation, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro YAMAGISHI, Tetsuya MARUYAMA, Masanori NAKAMURA, Asuka MATSUSHITA, Shogo YAMANAKA
  • Patent number: 9614621
    Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: April 4, 2017
    Assignee: Nippon Telegraph And Telephone Corporation
    Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Akihide Sano, Shogo Yamanaka, Etsushi Yamazaki, Yutaka Miyamoto, Eiji Yoshida, Tadao Nakagawa
  • Patent number: 9520947
    Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: December 13, 2016
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Akihide Sano, Shogo Yamanaka, Etsushi Yamazaki, Yutaka Miyamoto, Eiji Yoshida, Tadao Nakagawa
  • Publication number: 20150078762
    Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.
    Type: Application
    Filed: November 21, 2014
    Publication date: March 19, 2015
    Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Akihide Sano, Shogo Yamanaka, Etsushi Yamazaki, Yutaka Miyamoto, Eiji Yoshida, Tadao Nakagawa
  • Publication number: 20150078765
    Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.
    Type: Application
    Filed: November 21, 2014
    Publication date: March 19, 2015
    Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Akihide Sano, Shogo Yamanaka, Etsushi Yamazaki, Yutaka Miyamoto, Eiji Yoshida, Tadao Nakagawa
  • Patent number: 8929750
    Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.
    Type: Grant
    Filed: May 18, 2010
    Date of Patent: January 6, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Akihide Sano, Shogo Yamanaka, Etsushi Yamazaki, Yutaka Miyamoto, Eiji Yoshida, Tadao Nakagawa
  • Patent number: 8787769
    Abstract: In order to compensate for chromatic dispersion caused by optical fiber transmission in a communication system with coherent detection using optical signals, specific frequency band signals are used to enable estimation of a chromatic dispersion value.
    Type: Grant
    Filed: July 14, 2010
    Date of Patent: July 22, 2014
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Koichi Ishihara, Takayuki Kobayashi, Riichi Kudo, Yasushi Takatori, Munehiro Matsui, Masato Mizoguchi, Tadao Nakagawa, Etsushi Yamazaki, Akihide Sano, Yutaka Miyamoto, Eiji Yoshida, Shogo Yamanaka
  • Patent number: 8687973
    Abstract: A voltage generator (400) includes a resistor ladder including resistors (4000-4008) which divide a supplied voltage to generate a plurality of reference voltages, a resistor (4009) provided between a power supply voltage (VCC) and one terminal of the resistor ladder, and a resistor (4010) provided between a power supply voltage (VEE) and the other terminal of the resistor ladder.
    Type: Grant
    Filed: August 12, 2009
    Date of Patent: April 1, 2014
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hideyuki Nosaka, Munehiko Nagatani, Shogo Yamanaka, Kimikazu Sano, Koichi Murata, Kiyomitsu Onodera, Takatomo Enoki