Patents by Inventor Takashi Mitsui

Takashi Mitsui 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: 11929787
    Abstract: An optical transmission apparatus of an embodiment is an apparatus for redundantly transmitting a multiplexed signal obtained by multiplexing N (N is an integer of 2 or greater) optical signals having different wavelengths, the apparatus including: a first demultiplexing unit to which a first multiplexed signal is input, the first demultiplexing unit configured to demultiplex the input first multiplexed signal into the N optical signals; N first detection units to which the N optical signals demultiplexed by the first demultiplexing unit are respectively input, each of the N first detection units configured to detect presence or absence of deterioration of a corresponding input optical signals of the input optical signals based on a signal level of the corresponding input optical signal; a second demultiplexing unit to which a second multiplexed signal is input, the second demultiplexing unit configured to demultiplex the input second multiplexed signal into the N optical signals; N second detection units to
    Type: Grant
    Filed: March 13, 2020
    Date of Patent: March 12, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro Tanabe, Takashi Mitsui, Tomoaki Yoshida, Toshiaki Shitaba
  • Publication number: 20230353249
    Abstract: An optical transmission device includes a distribution unit which generates a first modulated signal and a second modulated signal by distribution processing for an input signal; a first phase modulator which generates a first optical signal phase-modulated in accordance with the first modulated signal by using a laser beam based on a first oscillation frequency; a phase adjustment unit which generates the second modulated signal of a phase opposite to a phase of the first modulated signal; a second phase modulator which generates a second optical signal phase-modulated in accordance with the second modulated signal of the opposite phase by using a laser beam based on a second oscillation frequency; a multiplexing unit which multiplexes the first optical signal and the second optical signal; and a detection unit which generates a frequency-modulated signal by performing square-law detection processing on a result of multiplexing.
    Type: Application
    Filed: September 1, 2020
    Publication date: November 2, 2023
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Toshiaki SHITABA, Tomoaki YOSHIDA, Akihiro TANABE, Takashi MITSUI
  • Publication number: 20230275658
    Abstract: In an optical transmission system including a plurality of optical transmitting units and a relay device, the plurality of optical transmitting units include a frequency modulation conversion unit that converts an input signal into a frequency modulation signal through frequency modulation conversion processing, a multiplexing unit that multiplexes monitoring signals with different frequencies with the frequency modulation signal, and an optical modulation unit that converts the frequency modulation signal that is an electric signal in which the monitoring signals are multiplexed into optical signals having different wavelengths, and the relay device includes a photoelectric conversion unit that acquires a combined signal obtained by combining optical signals having different wavelengths from each other and converts the combined signal into an electric signal, and a measuring unit that measures transmission quality of the plurality of monitoring signals included in the electric signal.
    Type: Application
    Filed: July 30, 2020
    Publication date: August 31, 2023
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Toshiaki SHITABA, Tomoaki YOSHIDA, Akihiro TANABE, Takashi MITSUI
  • Publication number: 20230254060
    Abstract: An apparatus includes a reception processing unit configured to output a frequency division multiplexed signal obtained from a transmission signal transmitted over the wired communication network, an output control unit configured to output, in a case that apparatus identifying data matches signal specifying data, a frequency band specifying data indicating a frequency band corresponding to the signal specifying data, the apparatus identifying data being for requesting signal quality degradation, and the signal specifying data specifying a carrier signal requesting signal quality degradation among a plurality of carrier signals included in the frequency division multiplexed signal, a disturbing signal generation unit configured to generate a disturbing signal in a frequency band corresponding to the frequency band specifying data output by the output control unit, and a multiplexing unit configured to multiplex the frequency division multiplexed signal and the disturbing signal to output.
    Type: Application
    Filed: July 2, 2020
    Publication date: August 10, 2023
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro TANABE, Toshiaki SHITABA, Takashi MITSUI, Tomoaki YOSHIDA
  • Publication number: 20230135622
    Abstract: An optical transmission apparatus includes an input unit, a demultiplexing unit, a measurement unit, and a switching unit. The input unit inputs a first multiplexed signal and a second multiplexed signal each obtained by multiplexing a plurality of optical signals having different wavelengths. The demultiplexing unit demultiplexes the first multiplexed signal and the second multiplexed signal by wavelength. The measurement unit measures qualities of a plurality of optical signals obtained by demultiplexing the first multiplexed signal and qualities of a plurality of optical signals obtained by demultiplexing the second multiplexed signal. The switching unit performs switching between the first multiplexed signal and the second multiplexed signal to be output to a subsequent stage based on a result of measurement by the measurement unit.
    Type: Application
    Filed: March 13, 2020
    Publication date: May 4, 2023
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro TANABE, Takashi MITSUI, Toshiaki SHITABA, Tomoaki YOSHIDA
  • Publication number: 20230099159
    Abstract: An optical transmission apparatus of an embodiment is an apparatus for redundantly transmitting a multiplexed signal obtained by multiplexing N (N is an integer of 2 or greater) optical signals having different wavelengths, the apparatus including: a first demultiplexing unit to which a first multiplexed signal is input, the first demultiplexing unit configured to demultiplex the input first multiplexed signal into the N optical signals; N first detection units to which the N optical signals demultiplexed by the first demultiplexing unit are respectively input, each of the N first detection units configured to detect presence or absence of deterioration of a corresponding input optical signals of the input optical signals based on a signal level of the corresponding input optical signal; a second demultiplexing unit to which a second multiplexed signal is input, the second demultiplexing unit configured to demultiplex the input second multiplexed signal into the N optical signals; N second detection units to
    Type: Application
    Filed: March 13, 2020
    Publication date: March 30, 2023
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro TANABE, Takashi MITSUI, Tomoaki YOSHIDA, Toshiaki SHITABA
  • Patent number: 11611470
    Abstract: A communication device including a first communication device and a plurality of second communication devices in an optical access system in which a first communication device and the plurality of second communication devices perform communications with each other under a time division multiple access scheme includes an Ethernet controller configured to implement the communications as Ethernet (registered trademark) communications, and a link failure processing unit configured to output, in response to reception of a link failure notification for notifying occurrence of a link failure in the communications from the first communication device, a termination instruction to terminate data transmission when the communication device is performing the data transmission to the first communication device, and a start instruction to start the data transmission after recovery from the link failure when the communication device is not performing the data transmission to the first communication device.
    Type: Grant
    Filed: July 5, 2019
    Date of Patent: March 21, 2023
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takamitsu Tochino, Takashi Mitsui, Tomoya Hatano
  • Patent number: 11575443
    Abstract: An optical transmission system includes: a first optical transmitting unit for transmitting a first optical signal having a first wavelength; a second optical transmitting unit for transmitting a second optical signal having a second wavelength; an output adjustment unit for acquiring the first optical signal and the second optical signal, adjusting signal intensities of the acquired optical signals, and outputting the optical signals; a multiplexer for multiplexing the first optical signal and the second optical signal that have been subjected to signal intensity adjustment and outputting a multiplexed signal; an amplifier for amplifying the multiplexed signal; a first optical receiving unit for receiving the amplified first optical signal; and a second optical receiving unit for receiving the amplified second optical signal.
    Type: Grant
    Filed: January 30, 2020
    Date of Patent: February 7, 2023
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takashi Mitsui, Toshiaki Shitaba, Akihiro Tanabe, Kengo Horikoshi, Hisao Yoshinaga
  • Patent number: 11444716
    Abstract: An optical transmission system includes: first and second optical transmitting units for respectively transmitting first and second optical signals that are obtained, respectively, as a result of first and second frequency-multiplexed multi-channel signals being converted by means of FM batch conversion; a carrier monitoring function unit for monitoring each carrier signal included in the optical signals; an output adjustment unit for adjusting signal intensities of the optical signals and outputting the optical signals; a multiplexer for outputting a multiplexed signal of the optical signals; an amplifier for amplifying the multiplexed signal; and first and second optical receiving units for receiving the respective optical signals included in the amplified multiplexed signal. The output adjustment unit adjusts the respective signal intensities of the optical signals such that the signal intensity at each optical receiving unit is larger than or equal to a predetermined value.
    Type: Grant
    Filed: January 31, 2020
    Date of Patent: September 13, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takashi Mitsui, Toshiaki Shitaba
  • Patent number: 11412316
    Abstract: An optical line terminal is provided with: an absorption unit that acquires first information of a type and a format that are dependent on a communication scheme and that converts the acquired first information into second information of a type and a format that are common to mutually different communication schemes; and a bandwidth allocation unit that determines bandwidth allocation of an upstream signal allocated to an optical network unit on the basis of the second information.
    Type: Grant
    Filed: June 6, 2019
    Date of Patent: August 9, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita Nishimoto, Takashi Mitsui, Tomoya Hatano
  • Publication number: 20220140906
    Abstract: An optical transmission system includes: a first optical transmitting unit for transmitting a first optical signal having a first wavelength; a second optical transmitting unit for transmitting a second optical signal having a second wavelength; an output adjustment unit for acquiring the first optical signal and the second optical signal, adjusting signal intensities of the acquired optical signals, and outputting the optical signals; a multiplexer for multiplexing the first optical signal and the second optical signal that have been subjected to signal intensity adjustment and outputting a multiplexed signal; an amplifier for amplifying the multiplexed signal; a first optical receiving unit for receiving the amplified first optical signal; and a second optical receiving unit for receiving the amplified second optical signal.
    Type: Application
    Filed: January 30, 2020
    Publication date: May 5, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takashi MITSUI, Toshiaki SHITABA, Akihiro TANABE, Kengo HORIKOSHI, Hisao YOSHINAGA
  • Publication number: 20220131633
    Abstract: An optical transmission system includes: first and second optical transmitting units for respectively transmitting first and second optical signals that are obtained, respectively, as a result of first and second frequency-multiplexed multi-channel signals being converted by means of FM batch conversion; a carrier monitoring function unit for monitoring each carrier signal included in the optical signals; an output adjustment unit for adjusting signal intensities of the optical signals and outputting the optical signals; a multiplexer for outputting a multiplexed signal of the optical signals; an amplifier for amplifying the multiplexed signal; and first and second optical receiving units for receiving the respective optical signals included in the amplified multiplexed signal. The output adjustment unit adjusts the respective signal intensities of the optical signals such that the signal intensity at each optical receiving unit is larger than or equal to a predetermined value.
    Type: Application
    Filed: January 31, 2020
    Publication date: April 28, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takashi MITSUI, Toshiaki SHITABA
  • Patent number: 11197077
    Abstract: Transmitting devices used in an optical access system in which a plurality of the transmitting devices transmit an optical burst signal to a receiving device by time division multiple access, the transmitting devices each including an arithmetic processing unit, the arithmetic processing unit including: a data signal transmission instruction unit, the a data signal transmission instruction unit that outputs a first instruction for controlling transmission processing of a data signal on the basis of a requester's instruction; an optical signal control instruction unit that outputs a second instruction for controlling output processing of an optical signal on the basis of the requester's instruction; and an instruction output adjustment unit that adjusts a timing at which the first instruction is output and a timing at which the second instruction is output.
    Type: Grant
    Filed: February 21, 2019
    Date of Patent: December 7, 2021
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takamitsu Tochino, Takashi Mitsui, Kota Asaka, Tomoya Hatano
  • Publication number: 20210297308
    Abstract: A communication device including a first communication device and a plurality of second communication devices in an optical access system in which a first communication device and the plurality of second communication devices perform communications with each other under a time division multiple access scheme includes an Ethernet controller configured to implement the communications as Ethernet (registered trademark) communications, and a link failure processing unit configured to output, in response to reception of a link failure notification for notifying occurrence of a link failure in the communications from the first communication device, a termination instruction to terminate data transmission when the communication device is performing the data transmission to the first communication device, and a start instruction to start the data transmission after recovery from the link failure when the communication device is not performing the data transmission to the first communication device.
    Type: Application
    Filed: July 5, 2019
    Publication date: September 23, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takamitsu TOCHINO, Takashi MITSUI, Tomoya HATANO
  • Publication number: 20210168475
    Abstract: An optical line terminal is provided with: an absorption unit that acquires first information of a type and a format that are dependent on a communication scheme and that converts the acquired first information into second information of a type and a format that are common to mutually different communication schemes; and a bandwidth allocation unit that determines bandwidth allocation of an upstream signal allocated to an optical network unit on the basis of the second information.
    Type: Application
    Filed: June 6, 2019
    Publication date: June 3, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita NISHIMOTO, Takashi MITSUI, Tomoya HATANO
  • Publication number: 20210168022
    Abstract: A first communication device in an optical access system in which the first communication device and a plurality of second communication devices communicate through a time division multiple access scheme includes: an Ethernet (registered trademark) controller configured to implement a communication as an Ethernet communication; a link failure detection unit configured to detect, when the plurality of second communication devices perform an initial connection to a network in the optical access system, whether a link failure has occurred based on collision detection of an optical signal transmitted by each of the plurality of second communication devices; and a signal processing unit configured to output, when the link failure detection unit detects that the link failure has not occurred, an initial connection start notification for causing initiation of a processing of the initial connection.
    Type: Application
    Filed: June 25, 2019
    Publication date: June 3, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takamitsu TOCHINO, Takashi MITSUI, Tomoya HATANO
  • Publication number: 20210051382
    Abstract: Transmitting devices used in an optical access system in which a plurality of the transmitting devices transmit an optical burst signal to a receiving device by time division multiple access, the transmitting devices each including an arithmetic processing unit, the arithmetic processing unit including: a data signal transmission instruction unit, the a data signal transmission instruction unit that outputs a first instruction for controlling transmission processing of a data signal on the basis of a requester's instruction; an optical signal control instruction unit that outputs a second instruction for controlling output processing of an optical signal on the basis of the requester's instruction; and an instruction output adjustment unit that adjusts a timing at which the first instruction is output and a timing at which the second instruction is output.
    Type: Application
    Filed: February 21, 2019
    Publication date: February 18, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takamitsu TOCHINO, Takashi MITSUI, Kota ASAKA, Tomoya HATANO
  • Publication number: 20200273546
    Abstract: A method for searching for a compound having a interaction with a target molecule includes growing a base fragment molecule and obtaining a grown molecule by performing molecular dynamics calculation using a reactive force field and bonding an atom to the base fragment molecule at a binding site of the target molecule.
    Type: Application
    Filed: January 14, 2020
    Publication date: August 27, 2020
    Applicant: FUJITSU LIMITED
    Inventor: Takashi MITSUI
  • Patent number: 9276670
    Abstract: A self-diagnostic method for PON protection system, in which optical switch-related failure can be previously inspected, and a PON protection system.
    Type: Grant
    Filed: November 15, 2012
    Date of Patent: March 1, 2016
    Assignee: Nippon Telegraoh and Telephone Corporation
    Inventors: Youichi Fukada, Takashi Mitsui, Takeshi Sakamoto, Naoto Yoshimoto, Yasutaka Kimura
  • Publication number: 20150321869
    Abstract: A transfer tool is provided with a grip member which can be gripped so that its axis is perpendicular to a transfer target surface or is inclined toward a direction of movement during transfer, a rotor which is held in the grip member and is able to rotate around the axis, and a transfer head which is held on the rotor with a transfer end deviated from the axis in a direction opposite to the direction of movement during transfer. The transfer tool is configured so that the transfer head can flexibly track the transfer target surface.
    Type: Application
    Filed: November 21, 2013
    Publication date: November 12, 2015
    Applicant: KOKUYO S&T Co., Ltd.
    Inventors: Keiji KAI, Takashi MITSUI, Megumi SASAYA, Hideto SHIMA