Patents by Inventor Mitsunori Fukutoku

Mitsunori Fukutoku 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: 11476635
    Abstract: An optically amplified repeater system includes optical transmission paths, a multi-channel optical amplifier, one or more Raman amplification pumping light sources, and a wavelength multiplexer. The multi-channel optical amplifier includes K simultaneous pumping light sources, N optical amplification media, and one or more optical couplers, and simultaneously amplifies, with the K simultaneous pumping light sources, light intensities of optical signals that pass through the N optical amplification media and propagate through the optical transmission paths. Light intensities of the wavelength band of the optical signals is Raman amplified by the Raman amplification pumping light. A light intensity of the Raman amplification pumping light output from the one or more Raman amplification pumping light sources is determined in accordance with characteristic differences between the optical signals passing through the optical transmission paths.
    Type: Grant
    Filed: August 24, 2018
    Date of Patent: October 18, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takayuki Mizuno, Akira Isoda, Kohki Shibahara, Mitsunori Fukutoku, Yutaka Miyamoto
  • Patent number: 11362753
    Abstract: An optical node device includes one or more input-side wavelength selection switches, a plurality of output-side wavelength selection switches, and an amplification unit. The input-side wavelength selection switches include a plurality of output ports, separate input light in accordance with a wavelength, and output the separated light from the output port corresponding to an output destination of the separated light. The output-side wavelength selection switches include input ports each receiving the light output from each of the one or more input-side wavelength selection switches, multiplex the light received from the input ports, and output the light. The amplification unit amplifies the light output from each of the output ports of the input-side wavelength selection switches and outputs the amplified light to the output-side wavelength selection switch at the output destination corresponding to the output port.
    Type: Grant
    Filed: February 1, 2019
    Date of Patent: June 14, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hirotaka Ono, Mitsunori Fukutoku, Shingo Kawai, Yutaka Miyamoto
  • Patent number: 11349524
    Abstract: A symbol-determining device according to an embodiment includes: a transmission line shortening unit that multiplies each symbol value of a symbol array that is part of an input signal by a tap gain of a linear digital filter and outputs a symbol array representing a sum of values acquired through the multiplication; a transmission line estimating unit that estimates a transfer function of a transmission line using an adaptive nonlinear digital filter on the basis of a symbol array representing a state of the transmission line; an addition comparison processing unit that calculates a minimum value of a distance function in a Viterbi algorithm on the basis of a metric that is calculated on the basis of the output of the transmission line shortening unit and the transfer function; and a path tracing-back determination unit that performs symbol determination by tracing back a trellis path in the Viterbi algorithm on the basis of the minimum value of the distance function.
    Type: Grant
    Filed: January 18, 2019
    Date of Patent: May 31, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hiroki Taniguchi, Shuto Yamamoto, Akira Masuda, Mitsunori Fukutoku
  • Publication number: 20210159996
    Abstract: An optical node device includes one or more input-side wavelength selection switches, a plurality of output-side wavelength selection switches, and an amplification unit. The input-side wavelength selection switches include a plurality of output ports, separate input light in accordance with a wavelength, and output the separated light from the output port corresponding to an output destination of the separated light. The output-side wavelength selection switches include input ports each receiving the light output from each of the one or more input-side wavelength selection switches, multiplex the light received from the input ports, and output the light. The amplification unit amplifies the light output from each of the output ports of the input-side wavelength selection switches and outputs the amplified light to the output-side wavelength selection switch at the output destination corresponding to the output port.
    Type: Application
    Filed: February 1, 2019
    Publication date: May 27, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hirotaka ONO, Mitsunori FUKUTOKU, Shingo KAWAI, Yutaka MIYAMOTO
  • Patent number: 10965375
    Abstract: An optical node device includes: a multicore optical amplification unit that amplifies collectively light transmitted along a multicore fiber; a separation unit that inputs the amplified light in each core to each of a plurality of input-side single-core fibers; an optical cross-connect switch that attenuates the light input from each of the plurality of input-side single-core fibers through an optical attenuator, separates the light in accordance with a wavelength, and outputs the separated light to an output-side single-core fiber of a plurality of output-side single-core fibers related to a respective output destination; a plurality of single-core optical amplification units that amplify the light transmitted along the corresponding output-side single-core fibers; and an output unit that outputs the light transmitted along each of the plurality of output-side single-core fibers to a multicore fiber.
    Type: Grant
    Filed: February 8, 2019
    Date of Patent: March 30, 2021
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hirotaka Ono, Kazunori Senoo, Kenya Suzuki, Keita Yamaguchi, Mitsunori Fukutoku, Shingo Kawai, Yutaka Miyamoto
  • Publication number: 20210036781
    Abstract: An optical node device includes: a multicore optical amplification unit that amplifies collectively light transmitted along a multicore fiber; a separation unit that inputs the amplified light in each core to each of a plurality of input-side single-core fibers; an optical cross-connect switch that attenuates the light input from each of the plurality of input-side single-core fibers through an optical attenuator, separates the light in accordance with a wavelength, and outputs the separated light to an output-side single-core fiber of a plurality of output-side single-core fibers related to a respective output destination; a plurality of single-core optical amplification units that amplify the light transmitted along the corresponding output-side single-core fibers; and an output unit that outputs the light transmitted along each of the plurality of output-side single-core fibers to a multicore fiber.
    Type: Application
    Filed: February 8, 2019
    Publication date: February 4, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hirotaka ONO, Kazunori SENOO, Kenya SUZUKI, Keita YAMAGUCHI, Mitsunori FUKUTOKU, Shingo KAWAI, Yutaka MIYAMOTO
  • Publication number: 20200389207
    Abstract: A symbol-determining device according to an embodiment includes: a transmission line shortening unit that multiplies each symbol value of a symbol array that is part of an input signal by a tap gain of a linear digital filter and outputs a symbol array representing a sum of values acquired through the multiplication; a transmission line estimating unit that estimates a transfer function of a transmission line using an adaptive nonlinear digital filter on the basis of a symbol array representing a state of the transmission line; an addition comparison processing unit that calculates a minimum value of a distance function in a Viterbi algorithm on the basis of a metric that is calculated on the basis of the output of the transmission line shortening unit and the transfer function; and a path tracing-back determination unit that performs symbol determination by tracing back a trellis path in the Viterbi algorithm on the basis of the minimum value of the distance function.
    Type: Application
    Filed: January 18, 2019
    Publication date: December 10, 2020
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hiroki TANIGUCHI, Shuto YAMAMOTO, Akira MASUDA, Mitsunori FUKUTOKU
  • Publication number: 20200381888
    Abstract: An optically amplified repeater system includes optical transmission paths, a multi-channel optical amplifier, one or more Raman amplification pumping light sources, and a wavelength multiplexer. The multi-channel optical amplifier includes K simultaneous pumping light sources, N optical amplification media, and one or more optical couplers, and simultaneously amplifies, with the K simultaneous pumping light sources, light intensities of optical signals that pass through the N optical amplification media and propagate through the optical transmission paths. Light intensities of the wavelength band of the optical signals is Raman amplified by the Raman amplification pumping light. A light intensity of the Raman amplification pumping light output from the one or more Raman amplification pumping light sources is determined in accordance with characteristic differences between the optical signals passing through the optical transmission paths.
    Type: Application
    Filed: August 24, 2018
    Publication date: December 3, 2020
    Applicant: Nippon Telegraph and Telephone Corporation
    Inventors: Takayuki MIZUNO, Akira ISODA, Kohki SHIBAHARA, Mitsunori FUKUTOKU, Yutaka MIYAMOTO
  • Patent number: 10756819
    Abstract: An encoding device includes an encoding unit, DA converters, light sources, intensity modulators, and wavelength multiplexers. The encoding unit adds (NM/2) to an encoded signal having a negative minimum value in a range of the encoded signal among encoded signals of N channels of (NM+1) values obtained by calculating an inner product of a Hadamard matrix of N rows and N columns and a matrix having elements of N intensity signals of (M+1) values. The DA converters of the channels convert the encoded signals of the channels from digital signals into electrical analog signals. The light sources output light of wavelengths for use in the channels. The light intensity modulators of the channels intensity-modulate the light output from the light sources with the encoded signals converted into the electrical analog signals by the DA converters. The wavelength multiplexer outputs a wavelength-multiplexed signal obtained by wavelength-multiplexing the light intensity-modulated by the light intensity modulators.
    Type: Grant
    Filed: April 7, 2020
    Date of Patent: August 25, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shuto Yamamoto, Akira Masuda, Yoshiaki Sone, Mitsunori Fukutoku
  • Publication number: 20200244369
    Abstract: An encoding device includes an encoding unit, DA converters, light sources, intensity modulators, and wavelength multiplexers. The encoding unit adds (NM/2) to an encoded signal having a negative minimum value in a range of the encoded signal among encoded signals of N channels of (NM+1) values obtained by calculating an inner product of a Hadamard matrix of N rows and N columns and a matrix having elements of N intensity signals of (M+1) values. The DA converters of the channels convert the encoded signals of the channels from digital signals into electrical analog signals. The light sources output light of wavelengths for use in the channels. The light intensity modulators of the channels intensity-modulate the light output from the light sources with the encoded signals converted into the electrical analog signals by the DA converters. The wavelength multiplexer outputs a wavelength-multiplexed signal obtained by wavelength-multiplexing the light intensity-modulated by the light intensity modulators.
    Type: Application
    Filed: April 7, 2020
    Publication date: July 30, 2020
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shuto YAMAMOTO, Akira MASUDA, Yoshiaki SONE, Mitsunori FUKUTOKU
  • Patent number: 10693562
    Abstract: An encoding device includes an encoding unit, DA converters, light sources, intensity modulators, and wavelength multiplexers. The encoding unit adds (NM/2) to an encoded signal having a negative minimum value in a range of the encoded signal among encoded signals of N channels of (NM+1) values obtained by calculating an inner product of a Hadamard matrix of N rows and N columns and a matrix having elements of N intensity signals of (M+1) values. The DA converters of the channels convert the encoded signals of the channels from digital signals into electrical analog signals. The light sources output light of wavelengths for use in the channels. The light intensity modulators of the channels intensity-modulate the light output from the light sources with the encoded signals converted into the electrical analog signals by the DA converters. The wavelength multiplexer outputs a wavelength-multiplexed signal obtained by wavelength-multiplexing the light intensity-modulated by the light intensity modulators.
    Type: Grant
    Filed: October 16, 2017
    Date of Patent: June 23, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shuto Yamamoto, Akira Masuda, Yoshiaki Sone, Mitsunori Fukutoku
  • Patent number: 10651945
    Abstract: An encoding device includes an encoding unit, DA converters, light sources, intensity modulators, and wavelength multiplexers. The encoding unit adds (NM/2) to an encoded signal having a negative minimum value in a range of the encoded signal among encoded signals of N channels of (NM+1) values obtained by calculating an inner product of a Hadamard matrix of N rows and N columns and a matrix having elements of N intensity signals of (M+1) values. The DA converters of the channels convert the encoded signals of the channels from digital signals into electrical analog signals. The light sources output light of wavelengths for use in the channels. The light intensity modulators of the channels intensity-modulate the light output from the light sources with the encoded signals converted into the electrical analog signals by the DA converters. The wavelength multiplexer outputs a wavelength-multiplexed signal obtained by wavelength-multiplexing the light intensity-modulated by the light intensity modulators.
    Type: Grant
    Filed: October 16, 2017
    Date of Patent: May 12, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shuto Yamamoto, Akira Masuda, Yoshiaki Sone, Mitsunori Fukutoku
  • Publication number: 20200052792
    Abstract: An encoding device includes an encoding unit, DA conveners, light sources, intensity modulators, and wavelength multiplexers. The encoding unit adds (NM/2) to an encoded signal having a negative minimum value in a range of the encoded signal among encoded signals of N channels of (NM+1) values obtained by calculating an inner product of a Hadamard matrix of N rows and N columns and a matrix having elements of N intensity signals of (M+1) values. The DA converters of the channels convert the encoded signals of the channels from digital signals into electrical analog signals. The light sources output light of wavelengths for use in the channels. The light intensity modulators of the channels intensity-modulate the light output from the light sources with the encoded signals converted into the electrical analog signals by the DA converters. The wavelength multiplexer outputs a wavelength-multiplexed signal obtained by wavelength-multiplexing the light intensity-modulated by the light intensity modulators.
    Type: Application
    Filed: October 16, 2017
    Publication date: February 13, 2020
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shuto YAMAMOTO, Akira MASUDA, Yoshiaki SONE, Mitsunori FUKUTOKU
  • Patent number: 9723387
    Abstract: To provide an optical signal processing device that can collect light from an input waveguide to form a beam array having a small diameter. The optical signal processing device includes input waveguides 302a to 302c, an array waveguide 305 and a slab waveguide 304 that is connected to a first arc 304a having the single point C as a center and input waveguides 302a to 302c and that is connected to a second arc 404b having the single point C as a center and an array waveguide 305.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: August 1, 2017
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kenya Suzuki, Kazunori Seno, Naoki Ooba, Tetsuo Takahashi, Toshio Watanabe, Takeshi Kawai, Mitsunori Fukutoku, Yuzo Ishii, Koichi Hadama, Yuichi Higuchi
  • Patent number: 9336080
    Abstract: A transmission system includes: an error correction encoding agent which converts an input data sequence into an encoded data sequence constituted of an error correction code and coded data; a data distribution agent which divides the encoded data sequence from the error correction encoding agent, in a predetermined processing unit and send them to a plurality of transmission routes; a data combining agent which combines signal sequences from the respective transmission routes and restores the encoded data sequence; an error correction decoding agent which applies error correction to and decodes the encoded data sequence from the data combining agent and outputs the input data sequence; and an agent for configuration in which a redundancy in the error correction encoding agent and a degree of splitting of the encoded data sequence in the data distribution agent are set.
    Type: Grant
    Filed: July 4, 2012
    Date of Patent: May 10, 2016
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akira Hirano, Mitsunori Fukutoku, Yoshiaki Kisaka, Yoshiaki Sone, Akihiro Kadohata, Takafumi Tanaka
  • Patent number: 9294826
    Abstract: A wavelength selection switch system includes a wavelength selection switch including an input port and an output port, a nonvolatile memory in which configuration information for controlling an operation of the wavelength selection switch is stored, a high-speed memory in which reading and writing can be performed at a higher speed than in the nonvolatile memory and that stores a copy of the configuration information stored in the nonvolatile memory, and a control unit that controls an operation of the wavelength selection switch based on the configuration information read from the high-speed memory, wherein the control unit periodically reads the configuration information stored in the nonvolatile memory and writes a copy of the read configuration information to the high-speed memory.
    Type: Grant
    Filed: February 5, 2013
    Date of Patent: March 22, 2016
    Assignees: Nippon Telegraph and Telephone Corporation, NTT Electronics Corporation
    Inventors: Tomoyoshi Kataoka, Mitsunori Fukutoku, Etsu Hashimoto, Akio Sahara, Norio Sato, Yosuke Takeuchi
  • Patent number: 9247324
    Abstract: A wavelength selection switch system includes a wavelength selection switch including an input port and an output port, a nonvolatile memory in which configuration information for controlling an operation of the wavelength selection switch is stored, a high-speed memory in which reading and writing can be performed at a higher speed than in the nonvolatile memory and that stores a copy of the configuration information stored in the nonvolatile memory, and a control unit that controls an operation of the wavelength selection switch based on the configuration information read from the high-speed memory, wherein the control unit periodically reads the configuration information stored in the nonvolatile memory and writes a copy of the read configuration information to the high-speed memory.
    Type: Grant
    Filed: February 5, 2013
    Date of Patent: January 26, 2016
    Assignees: Nippon Telegraph and Telephone Corporation, NTT Electronics Corporation
    Inventors: Tomoyoshi Kataoka, Mitsunori Fukutoku, Etsu Hashimoto, Akio Sahara, Norio Sato, Yosuke Takeuchi
  • Publication number: 20150237420
    Abstract: To provide an optical signal processing device that can collect light from an input waveguide to form a beam array having a small diameter. The optical signal processing device includes input waveguides 302a to 302c, an array waveguide 305 and a slab waveguide 304 that is connected to a first arc 304a having the single point C as a center and input waveguides 302a to 302c and that is connected to a second arc 404b having the single point C as a center and an array waveguide 305.
    Type: Application
    Filed: September 27, 2013
    Publication date: August 20, 2015
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kenya Suzuki, Kazunori Seno, Naoki Ooba, Tetsuo Takahashi, Toshio Watanabe, Takeshi Kawai, Mitsunori Fukutoku, Yuzo Ishii, Koichi Hadama, Yuichi Higuchi
  • Publication number: 20150030327
    Abstract: A wavelength selection switch system includes a wavelength selection switch including an input port and an output port, a nonvolatile memory in which configuration information for controlling an operation of the wavelength selection switch is stored, a high-speed memory in which reading and writing can be performed at a higher speed than in the nonvolatile memory and that stores a copy of the configuration information stored in the nonvolatile memory, and a control unit that controls an operation of the wavelength selection switch based on the configuration information read from the high-speed memory, wherein the control unit periodically reads the configuration information stored in the nonvolatile memory and writes a copy of the read configuration information to the high-speed memory.
    Type: Application
    Filed: February 5, 2013
    Publication date: January 29, 2015
    Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT Electronics Corporation
    Inventors: Tomoyoshi Kataoka, Mitsunori Fukutoku, Etsu Hashimoto, Akio Sahara, Norio Sato, Yosuke Takeuchi
  • Publication number: 20140108894
    Abstract: A transmission system comprising: an error correction encoding agent which converts an input data sequence into a coded data sequence constituted of an error correction code and coded data; a data distribution agent which divides encoded data sequence from the error correction encoding agent, in a predetermined processing unit and combines the divided data sequences with a plurality of transmission routes; a data combining agent which combines signal sequences from the respective transmission routes and decodes encoded data sequence; an error correction decoding agent which applies error correction to and decodes encoded data sequence from the data combining agent and outputs the input data sequence; and an agent for configuration in which a redundancy in the error correction encoding agent and a degree of splitting of encoded data sequence in the data distribution agent are set.
    Type: Application
    Filed: July 4, 2012
    Publication date: April 17, 2014
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akira Hirano, Mitsunori Fukutoku, Yoshiaki Kisaka, Yoshiaki Sone, Akihiro Kadohata, Takafumi Tanaka