Patents by Inventor Tetsuro Inui

Tetsuro Inui 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).

  • Publication number: 20210028857
    Abstract: There is provided an optical transmission system in which a plurality of optical transmission and reception apparatuses perform 1-to-N transmission and reception of optical signals (N is an integer equal to or greater than 1), the optical transmission system being configured to select a communication condition that includes at least a modulation scheme or a baud rate and is a communication condition when each of the optical transmission and reception apparatuses performs transmission and reception in accordance with a transmission line condition that is between any one first optical transmission and reception apparatus and each of second optical transmission and reception apparatuses, which are N grounds, other than the first optical transmission and reception apparatus.
    Type: Application
    Filed: March 1, 2019
    Publication date: January 28, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Fumikazu INUZUKA, Shokei KOBAYASHI, Akira HIRANO, Wataru KAWAKAMI, Tetsuro INUI, Seiki KUWABARA, Kei KITAMURA, Takafumi TANAKA, Takuya ODA, Hideki NISHIZAWA, Seiji OKAMOTO
  • Publication number: 20210013963
    Abstract: A state estimating device includes a pre-processing unit and an estimating unit. The pre-processing unit acquires data representing at one or more of a phase of a signal transmitted from a transmission unit of a transmission device and received at a reception unit of another transmission device via a transmission path, a reception strength, a reception quality, a voltage after conversion into an electric signal, and a signal processing parameter used in reception processing, and processes the acquired data into feature data to be used for state estimation. The estimating unit estimates a state of the transmission path, an abnormal state of the transmission unit, or an abnormal state of the reception unit, on the basis of the feature data.
    Type: Application
    Filed: February 13, 2019
    Publication date: January 14, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Seiki KUWABARA, Wataru KAWAKAMI, Hideki NISHIZAWA, Seiji OKAMOTO, Akira HIRANO, Shokei KOBAYASHI, Tetsuro INUI, Takuya ODA, Fumikazu INUZUKA, Takafumi TANAKA
  • Patent number: 10686520
    Abstract: A transmission quality estimation system includes, three or more nodes and a transmission quality estimation device configured to estimate, transmission quality. A multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes. A node of the nodes includes a core connection unit configured to drop, add or relay light transmitted from, to or to each of to the plurality of cores of the multi-core fiber. The transmission quality estimation device includes an estimation unit configured to estimate transmission quality between the nodes on the basis of a transmission quality measurement light dropped by the core connection unit.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: June 16, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Oda, Tetsuro Inui, Akira Hirano, Wataru Imajuku, Shoukei Kobayashi, Takafumi Tanaka, Yutaka Miyamoto, Hidehiko Takara
  • Patent number: 10637568
    Abstract: A transmission quality estimation system includes, three or more nodes and a transmission quality estimation device configured to estimate, transmission quality. A multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes. A node of the nodes includes a core connection unit configured to drop, add or relay light transmitted from, to or to each of to the plurality of cores of the multi-core fiber. The transmission quality estimation device includes an estimation unit configured to estimate transmission quality between the nodes on the basis of a transmission quality measurement light dropped by the core connection unit.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: April 28, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Oda, Tetsuro Inui, Akira Hirano, Wataru Imajuku, Shoukei Kobayashi, Takafumi Tanaka, Yutaka Miyamoto, Hidehiko Takara
  • Patent number: 10615868
    Abstract: A communication system which includes: three or more nodes; a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes; a detection signal output unit configured to output a fault detection signal transmitted by the core provided in the multi-core fiber configured to connect together the nodes; and a fault detection unit configured to determine whether a fault has occurred between the nodes on the basis of a detection result of the fault detection signal.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: April 7, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Oda, Tetsuro Inui, Akira Hirano, Wataru Imajuku, Shoukei Kobayashi, Takafumi Tanaka, Yutaka Miyamoto, Hidehiko Takara
  • Patent number: 10527781
    Abstract: A communication system includes three or more nodes and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes is provided. One node of the nodes is connected to the multi-core fiber and includes a connector configured to add and drop a signal to and from an allocated core exclusively allocated from among the cores as a communication path between the one node and another node of the nodes and/or configured to relay a signal transmitted through another core of the cores allocated for communication between other nodes in the multi-core fiber connected to the one node, and a relative positional relationship between a connection position of the allocated core in which a signal is added or dropped in the connector and a connection position of another core in which a signal is relayed in the connector is the same for all of the nodes connected to the multi-core fiber.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: January 7, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Oda, Tetsuro Inui, Akira Hirano, Wataru Imajuku, Shoukei Kobayashi, Takafumi Tanaka, Yutaka Miyamoto, Hidehiko Takara
  • Patent number: 10511381
    Abstract: A communication system includes three or more nodes, and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes, wherein each of nodes includes: a fault information transmitting device configured to transmit fault information indicating that a fault has occurred in a communication path between one node and another node of the nodes when it is detected that it is not possible to perform communication between the one node and the another node; and a fault location specifying device configured to specify a section between nodes in which a fault has occurred on the basis of the fault information received from the fault information transmitting device provided in each of the nodes.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: December 17, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Oda, Tetsuro Inui, Akira Hirano, Wataru Imajuku, Shoukei Kobayashi, Takafumi Tanaka, Yutaka Miyamoto, Hidehiko Takara
  • Publication number: 20180375579
    Abstract: A communication system includes three or more nodes and a multi-core fiber having a plurality of cores and being used in at least a partial segment of the connection between the nodes. One node of the nodes is connected to the multi-core fiber and includes a connector configured to add and drop a signal to and from an allocated core exclusively allocated for communication between the one node and another node of the nodes and/or configured to relay a signal transmitted through another core allocated to communication between the other nodes in multi-core fibers connected to the one node.
    Type: Application
    Filed: November 22, 2016
    Publication date: December 27, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Publication number: 20180358773
    Abstract: An optical amplification system includes: three or more nodes; a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes; an amplification light input unit configured to input amplification light to a core of the plurality of cores of the multi-core fiber; an amplification unit configured to amplify communication light transmitted through at least one core of the plurality of cores of the multi-core fiber using the amplification light, the amplification unit being provided in the nodes or between the nodes; and an amplification light coupling unit configured to couple the amplification light input by the amplification light input unit to the amplification unit.
    Type: Application
    Filed: November 22, 2016
    Publication date: December 13, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Publication number: 20180359024
    Abstract: A communication system which includes: three or more nodes; a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes; a detection signal output unit configured to output a fault detection signal transmitted by the core provided in the multi-core fiber configured to connect together the nodes; and a fault detection unit configured to determine whether a fault has occurred between the nodes on the basis of a detection result of the fault detection signal.
    Type: Application
    Filed: November 22, 2016
    Publication date: December 13, 2018
    Applicant: Nippon Telegraph and Telephone Corporation
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Publication number: 20180351639
    Abstract: A communication system includes three or more nodes, and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes, wherein each of nodes includes: a fault information transmitting device configured to transmit fault information indicating that a fault has occurred in a communication path between one node and another node of the nodes when it is detected that it is not possible to perform communication between the one node and the another node; and a fault location specifying device configured to specify a section between nodes in which a fault has occurred on the basis of the fault information received from the fault information transmitting device provided in each of the nodes
    Type: Application
    Filed: November 22, 2016
    Publication date: December 6, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Publication number: 20180343067
    Abstract: A node included in an optical power supply system which includes three or more nodes and a multi-core fiber having a plurality of cores, the plurality of cores being used in at least a partial segment of the connection between the nodes includes: a power supply light dropping unit configured to drop a portion or all of a power supply light from one core of the plurality of cores of the multi-core fiber; a photoelectric conversion unit configured to convert the portion or all of the power supply light dropped by the power supply light dropping unit to an electrical signal; and a power supply target facility configured to operate with the electrical signal converted by the photoelectric conversion unit.
    Type: Application
    Filed: November 22, 2016
    Publication date: November 29, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Publication number: 20180341060
    Abstract: A communication system includes three or more nodes and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes is provided. One node of the nodes is connected to the multi-core fiber and includes a connector configured to add and drop a signal to and from an allocated core exclusively allocated from among the cores as a communication path between the one node and another node of the nodes and/or configured to relay a signal transmitted through another core of the cores allocated for communication between other nodes in the multi-core fiber connected to the one node, and a relative positional relationship between a connection position of the allocated core in which a signal is added or dropped in the connector and a connection position of another core in which a signal is relayed in the connector is the same for all of the nodes connected to the multi-core fiber.
    Type: Application
    Filed: November 22, 2016
    Publication date: November 29, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Publication number: 20180337726
    Abstract: A transmission quality estimation system includes, three or more nodes and a transmission quality estimation device configured to estimate, transmission quality. A multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of a connection between the nodes. A node of the nodes includes a core connection unit configured to drop, add or relay light transmitted from, to or to each of to the plurality of cores of the multi-core fiber. The transmission quality estimation device includes an estimation unit configured to estimate transmission quality between the nodes on the basis of a transmission quality measurement light dropped by the core connection unit.
    Type: Application
    Filed: November 22, 2016
    Publication date: November 22, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya ODA, Tetsuro INUI, Akira HIRANO, Wataru IMAJUKU, Shoukei KOBAYASHI, Takafumi TANAKA, Yutaka MIYAMOTO, Hidehiko TAKARA
  • Patent number: 7668459
    Abstract: In a wavelength division multiplexing optical transmission system, in order to know an influence amount of a temperature dependency of a dispersion slope, a method of monitoring a dispersion variation amount in two or more of wavelength channels is provided. Further, a method of compensating a wavelength dependency of a temperature dependency of the dispersion by providing an appropriate dispersion individually to the channels or summarizingly for all of bandwidths based on the monitored dispersion variation amounts is provided. According to the present invention, in the WDM optical transmission system, a deterioration in a transmission characteristic by influence of a temperature variation of the dispersion slope can be reduced.
    Type: Grant
    Filed: July 21, 2003
    Date of Patent: February 23, 2010
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tetsuro Inui, Hidehiko Takara, Takashi Yamamoto
  • Publication number: 20080296481
    Abstract: A chirp measurement apparatus includes a splitting section for splitting input signal light to two paths; a first dispersion medium with a total dispersion amount of +D (?0) at a used wavelength, and a second dispersion medium with a total dispersion amount of ?D (?0) at the used wavelength; first and second nonlinear photo-detecting sections for receiving the signal light beams passing through the first and second dispersion media, and for outputting electric signals with the intensities proportional to nth power of the intensities of the signal light beams, where n is greater than one; and a difference detecting section for computing a difference between the electric signals output from the first and second nonlinear photo-detecting sections, and for outputting a differential signal corresponding to the difference as a chirp signal of the input signal light.
    Type: Application
    Filed: May 2, 2008
    Publication date: December 4, 2008
    Inventors: Tetsuro Inui, Kunihiko Mori, Kohichi Robert Tamura
  • Publication number: 20080212962
    Abstract: A chirp measurement apparatus includes a splitting section for splitting input signal light to two paths; a first dispersion medium with a total dispersion amount of +D (?0) at a used wavelength, and a second dispersion medium with a total dispersion amount of ?D (?0) at the used wavelength; first and second nonlinear photo-detecting sections for receiving the signal light beams passing through the first and second dispersion media, and for outputting electric signals with the intensities proportional to nth power of the intensities of the signal light beams, where n is greater than one; and a difference detecting section for computing a difference between the electric signals output from the first and second nonlinear photo-detecting sections, and for outputting a differential signal corresponding to the difference as a chirp signal of the input signal light.
    Type: Application
    Filed: May 2, 2008
    Publication date: September 4, 2008
    Inventors: Tetsuro Inui, Kunihiko Mori, Kohichi Robert Tamura
  • Publication number: 20070242956
    Abstract: In a wavelength division multiplexing optical transmission system, in order to know an influence amount of a temperature dependency of a dispersion slope, a method of monitoring a dispersion variation amount in two or more of wavelength channels is provided. Further, a method of compensating a wavelength dependency of a temperature dependency of the dispersion by providing an appropriate dispersion individually to the channels or summarizingly for all of bandwidths based on the monitored dispersion variation amounts is provided. According to the present invention, in the WDM optical transmission system, a deterioration in a transmission characteristic by influence of a temperature variation of the dispersion slope can be reduced.
    Type: Application
    Filed: July 21, 2003
    Publication date: October 18, 2007
    Inventors: Tetsuro Inui, Hidehiko Takara, Takashi Yamamoto
  • Patent number: 7153613
    Abstract: The invention relates to a process for the fabrication of an optical fiber-processing phase mask that is reduced in terms of pitch variations on the mask and stitching errors, and provides a process for the fabrication of a chirped type optical fiber-processing phase mask wherein a grating form of grooves provided in one surface of a quartz substrate is configured as an optical fiber-processing grating pattern. At an exposure step, writing data obtained by arranging and compiling a plurality of data for a repetitive groove-and-strip pattern while the pitch of repetition is modulated are used and an electron beam resist is provided on a phase mask blank, so that writing is carried out all over the writing area on said phase mask blank continuously in a vertical direction to said grating form of grooves.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: December 26, 2006
    Assignees: Dai Nippon Printing Co., Ltd., Nippon Telegraph and Telephone Corporation
    Inventors: Masaaki Kurihara, Shigekazu Fujimoto, Tetsuro Komukai, Tetsuro Inui
  • Publication number: 20060022123
    Abstract: A chirp measurement apparatus includes a splitting section for splitting input signal light to two paths; a first dispersion medium with a total dispersion amount of +D (?0) at a used wavelength, and a second dispersion medium with a total dispersion amount of ?D (?0) at the used wavelength; first and second nonlinear photo-detecting sections for receiving the signal light beams passing through the first and second dispersion media, and for outputting electric signals with the intensities proportional to nth power of the intensities of the signal light beams, where n is greater than one; and a difference detecting section for computing a difference between the electric signals output from the first and second nonlinear photo-detecting sections, and for outputting a differential signal corresponding to the difference as a chirp signal of the input signal light.
    Type: Application
    Filed: September 23, 2005
    Publication date: February 2, 2006
    Inventors: Tetsuro Inui, Kunihiko Mori, Kohichi Tamura