Patents by Inventor Takuya Kanai

Takuya Kanai 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: 12206461
    Abstract: There is provided an optical power feeding system including: an optical power feeding unit; and a plurality of drop units configured to be able to receive light from the optical power feeding unit as an input, branch the input light, and output branched light, in which, the optical power feeding unit includes a power-feed light generating unit that outputs power-feed light, and the drop unit includes: an optical splitter that branches the power-feed light into first branch light and second branch light and outputs the second branch light to another drop unit; a photoelectric conversion unit that performs photoelectric conversion of the first branch light; and a branch ratio control unit that is driven by electricity generated by the photoelectric conversion and controls a branch ratio that is a ratio between the first branch light and the second branch light.
    Type: Grant
    Filed: July 29, 2020
    Date of Patent: January 21, 2025
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo Igarashi, Masamichi Fujiwara, Takuya Kanai
  • Patent number: 12199664
    Abstract: A light leakage confirmation method comprising: an excitation light incident step in which an excitation light output unit connected to a first end of a first optical transmission line outputs an excitation light and makes the excitation light incident on the first optical transmission line; a reflection step in which an excitation light reflection unit connected to a second end of the first optical transmission line reflects the excitation light which has been incident in the excitation light incident step; a reflected light incident step of making a reflected light which has been reflected in the reflection step incident on the first optical transmission line; a reflected light measurement step in which the excitation light output unit measures an intensity of the reflected light; and a leakage determination step of determining whether or not the excitation light is leaked on a basis of the intensity of the excitation light and the intensity of the reflected light which has been measured in the reflected li
    Type: Grant
    Filed: May 28, 2020
    Date of Patent: January 14, 2025
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo Igarashi, Masamichi Fujiwara, Takuya Kanai
  • Publication number: 20250016480
    Abstract: An aspect of the present invention is an optical transmission device including a connector that is able to be connected to an accommodation module accommodating an optical fiber such that optical communication is performed, an optical switch that receives an optical signal from the connector and outputs an optical signal to the connector, an optical switch controller that controls the optical switch, an up wavelength multiplexer/demultiplexer that multiplexes light of a plurality of wavelengths output from the optical switch and outputs the multiplexed light to a transmission line, and a down wavelength multiplexer/demultiplexer that demultiplexes light input from the transmission line and outputs the demultiplexed light to the optical switch, wherein the connector can be connected to any one of a one-core accommodation module and a two-core accommodation module as the accommodation module.
    Type: Application
    Filed: November 19, 2021
    Publication date: January 9, 2025
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Naotaka SHIBATA, Shin KANEKO, Takuya KANAI, Tomoaki YOSHIDA
  • Publication number: 20250016479
    Abstract: An optical node device to which a first subscriber device and a second subscriber device are connected in an optical communication system in which the first subscriber device and the second subscriber device are mixed, the first subscriber device being connected by one core using different wavelengths in transmission and reception, the second subscriber device being connected by two cores using the same wavelength in transmission and reception, the optical node device including: a transmission/reception separator that transfers an optical signal transmitted from the first subscriber device and an optical signal addressed to the first subscriber device without interference; and an optical switch that controls a connection relationship between ports such that an optical signal transmitted from the first subscriber device or an optical signal addressed to the first subscriber device passes through the transmission/reception separator and an optical signal transmitted from the second subscriber device or an optic
    Type: Application
    Filed: December 2, 2021
    Publication date: January 9, 2025
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya KANAI, Shin KANEKO, Naotaka SHIBATA, Junichi KANI, Tomoaki YOSHIDA
  • Publication number: 20250016481
    Abstract: An optical communication system including an optical switch that is connected to a plurality of optical transmission lines and outputs an optical signal input from any of the optical transmission lines to another optical transmission line, and a transfer unit configured to convert simplex transmission into duplex transmission or converts duplex transmission into simplex transmission between a subscriber device and the optical switch or between a first port of the optical switch to which the subscriber device is directly or indirectly connected and a second port opposite to the first port, and transfers the optical signal so as not to cause interference between uplink and downlink.
    Type: Application
    Filed: November 25, 2021
    Publication date: January 9, 2025
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Naotaka SHIBATA, Shin KANEKO, Takuya KANAI
  • Patent number: 12191905
    Abstract: The optical communication system includes the optical distribution device (100) provided between the wavelength routing device (30) and the optical multiplexing/demultiplexing device (40). The wavelength routing device outputs the optical signal input from the port on the wavelength variable subscriber device side to the port uniquely determined by a combination of the wavelength of the optical signal and the port to which the optical signal is inputted. The wavelength variable subscriber device can execute the first protection for switching the wavelength of the optical signal to be transmitted and received to the spare wavelength different from the operating wavelength when the wavelength variable subscriber device and the wavelength variable communication device (10) are disconnected.
    Type: Grant
    Filed: August 24, 2020
    Date of Patent: January 7, 2025
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shin Kaneko, Kazuaki Honda, Hiroo Suzuki, Junichi Kani, Takuya Kanai, Yasunari Tanaka
  • Publication number: 20250007610
    Abstract: An optical communication system including a subscriber device that performs optical connection with other subscriber device by End-End, and a management control device that controls each subscriber device, wherein the subscriber device includes an optical signal transmission unit configured to transmit an optical signal, an optical signal reception unit configured to receive an optical signal transmitted from the other subscriber device, and an output function unit configured to output an optical signal outputted by the optical signal transmission unit to an optical transmission line regardless of a wavelength and outputs an optical signal inputted from the optical transmission line to the optical signal reception unit regardless of the wavelength, and the management control device allocates wavelengths so that a transmission wavelength of the subscriber device becomes a reception wavelength of the other subscriber device and a transmission wavelength of the other subscriber device becomes a reception wavelen
    Type: Application
    Filed: November 18, 2021
    Publication date: January 2, 2025
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shin KANEKO, Takuya KANAI, Naotaka SHIBATA, Junichi KANI
  • Publication number: 20250008248
    Abstract: An optical switch having a plurality of ports outputs an optical signal received from a first port that is one of the plurality of ports connected to an optical communication device from a second port that another one of the plurality of ports according to a transmission path of an optical signal. An optical branching part branches an optical signal which has been output from a second port in accordance with a branching ratio. A measurement part measures a round trip time by transmitting and receiving an optical signal to and from an optical communication device through an optical switch, and calculates a transmission distance of the optical signal on the basis of the measured round trip time. An instruction part instructs, the optical branching part, of the branching ratio determined on the basis of the calculated transmission distance.
    Type: Application
    Filed: November 16, 2021
    Publication date: January 2, 2025
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yasunari TANAKA, Takuya KANAI, Kazutaka HARA, Yumiko SENOO, Shin KANEKO, Junichi KANI
  • Publication number: 20240388821
    Abstract: An optical communication system including: a management control device that manages communication between one or more first subscriber devices and one or more second subscriber devices that are provided at counterpart locations of the one or more first subscriber devices, in which the management control device includes a control signal generation unit that generates a control signal that is transmitted to the one or more first subscriber devices and used for management and control, and an optical transmission unit that converts the control signal generated by the control signal generation unit into an optical signal with a wavelength that is different from a wavelength of a main signal transmitted by the one or more second subscriber devices that perform communication with the one or more first subscriber devices and transmits the optical signal, and the optical communication system includes an optical multiplexing unit that is provided on a communication path between the one or more first subscriber devices
    Type: Application
    Filed: September 16, 2021
    Publication date: November 21, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shin KANEKO, Takuya KANAI, Kazutaka HARA, Junichi KANI
  • Publication number: 20240381012
    Abstract: Provided is an optical access system that performs communication using an optical signal on which a management control signal used for management and control is superimposed, the optical access system including: a subscriber device on a transmitting side that generates an optical signal by superimposing the management control signal on a main signal and transmits the generated optical signal; a management control unit that outputs a management control signal which is superimposed on the optical signal transmitted by the subscriber device on the transmitting side and which has a frequency band different from a frequency of the management control signal superimposed on the optical signal; and a control signal superimposing unit that superimposes the management control signal output from the management control unit on the optical signal.
    Type: Application
    Filed: April 19, 2021
    Publication date: November 14, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kazutaka HARA, Junichi KANI, Shin KANEKO, Takuya KANAI, Yumiko SENOO
  • Patent number: 12143157
    Abstract: A branch ratio setting system includes: a branch ratio control unit; and a plurality of drop units configured to be able to receive an optical signal from the branch ratio control unit, and configured to branch and output the received optical signal, and the branch ratio control unit outputs light to the plurality of drop units via an optical fiber to measure characteristics of the optical fiber, and outputs a branch ratio determination signal to each of the plurality of drop units via the optical fiber based on the measured characteristics of the optical fiber, and the drop unit includes an optical splitter connected to the optical fiber and having a variable branch ratio and a branch ratio setting unit that sets the branch ratio of the optical splitter based on the branch ratio determination signal input via the optical fiber.
    Type: Grant
    Filed: July 29, 2020
    Date of Patent: November 12, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo Igarashi, Masamichi Fujiwara, Takuya Kanai
  • Publication number: 20240372625
    Abstract: One mode of the present invention is an optical communication device that includes: a detector that detects the falling edge or the rising edge of a control signal outputted from a user device to an optical communication path; and an optical modulator that superimposes a new control signal on a main signal, when the falling edge or the rising edge of a control signal has been detected by the detector.
    Type: Application
    Filed: May 21, 2021
    Publication date: November 7, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya KANAI, Kazuaki HONDA, Yasunari TANAKA, Shin KANEKO, Kazutaka HARA
  • Patent number: 12119869
    Abstract: An optical amplification estimation method includes by an excitation light output unit connected to a first end of a first optical transmission line, making excitation light incident on the first optical transmission line, by a monitoring unit connected to the same side as the first end of the first optical transmission line, making monitoring light incident on the first optical transmission line, the monitoring light having a wavelength different from a wavelength of the excitation light, by the monitoring unit, measuring intensity of light incident on the monitoring unit when the excitation light is incident, and intensity of light incident on the monitoring unit when the excitation light is not incident, and by an amplification estimation unit, estimating a gain of an optical signal in the first optical transmission line based on the light intensity measured in the measuring.
    Type: Grant
    Filed: May 28, 2020
    Date of Patent: October 15, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo Igarashi, Masamichi Fujiwara, Takuya Kanai
  • Patent number: 12101124
    Abstract: An aspect of the present disclosure is a transmission system including a modulated wave generation unit that generates an intermediate wave, which is a coherent wave in which a frequency component of either of two signals overlays a frequency spectrum, the two signals being a main signal indicating transmitted information to be transmitted and a control signal indicating management information, which is information on communication between a transmission source of the transmitted information and a communication destination of the transmission source, and a modulation unit that modulates the intermediate wave with a signal in which a frequency component does not overlay the frequency spectrum of the coherent wave generated by the modulated wave generation unit out of the two signals that are the main signal and the control signal. In the transmission system, a frequency band of the main signal and a frequency band of the control signal do not overlap each other.
    Type: Grant
    Filed: April 24, 2020
    Date of Patent: September 24, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Kanai, Shin Kaneko, Kazuaki Honda, Junichi Kani, Hiroo Suzuki
  • Publication number: 20240276128
    Abstract: A communication method includes, in a state where first information equipment and second information equipment are communicatively connected via optical switches and an optical communication network, switching, by an optical switch to which the first information equipment is connected, a connection destination of the first information equipment from an input/output port connected to the optical communication network to a control port to which the control device is connected in response to a predetermined operation of the first information equipment, receiving, by the control device, information indicating third information equipment that is a communication connection destination different from the second information equipment via the control port of the optical switches from the first information equipment, allocating, by the control device, a wavelength used for communication to the first information equipment and the third information equipment based on information indicating the communication connection de
    Type: Application
    Filed: August 2, 2021
    Publication date: August 15, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yumiko SENOO, Kazutaka HARA, Shin KANEKO, Takuya KANAI, Kazuaki HONDA, Junichi KANI
  • Publication number: 20240187099
    Abstract: An optical switch receives an input of an optical signal which has been transmitted by a first optical communication device from a first port, and outputs the optical signal from a second port connected to a first optical transmission line included in an optical route in which an optical path between the first optical communication device and a second optical communication device is set. An optical branching unit branches a part of the optical signal which has been transmitted through the first optical transmission line, and outputs the branched optical signal to a second optical transmission line. An optical transmitting and receiving apparatus includes a reception unit, a transmission unit, and a light cutoff unit. The reception unit receives an input of the optical signal which has been branched by the optical branching unit from the second optical transmission line, and acquires a signal addressed to a destination different from the second optical communication device from the input optical signal.
    Type: Application
    Filed: April 14, 2021
    Publication date: June 6, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shin KANEKO, Junichi KANI, Kazutaka HARA, Takuya KANAI
  • Patent number: 11921333
    Abstract: A wavelength-selective optical reception device includes a photoreceptor (21) that converts optical signals (201) into electric signals and outputs the electric signals, a base (31) on which the photoreceptor (21) is provided, a housing (41) that is mounted on the base (31) and surrounds the photoreceptor (21) along with the base (31), and that is provided with a window (51) to pass optical signals (203) including the optical signals (201) and including optical signals (202) of a wavelength different from a first wavelength of the optical signals (201) and a window (52) to pass the optical signals (202), and an optical filter (61) that is disposed inside the housing between the window (51) and the photoreceptor (21) along the optical axis (205) of the optical signals (203), and that outputs, out of the optical signals (203) that enter thereto, the optical signals (201) toward the photoreceptor (21), and reflects the optical signals (202) toward a near side in a direction of travel of the optical signals (203)
    Type: Grant
    Filed: January 31, 2020
    Date of Patent: March 5, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya Kanai, Takeshi Imai, Yumiko Senoo, Kota Asaka
  • Publication number: 20240031035
    Abstract: A coherent optical reception device includes a coherent receiver that receives signal light in which an AMCC signal is superimposed on a main signal by phase modulation and outputs a reception signal and a digital signal processor, in which a modulation signal of the AMCC signal superimposed on the main signal is multiplied by a clock, the digital signal processor includes a symbol output, an AMCC signal code sequence demodulator, and a main signal code sequence demodulator, and the AMCC signal code sequence demodulator includes a main signal component remover that removes the main signal included in the reception signal output from the symbol output, and a clock component remover that removes a clock component included in the reception signal from which the main signal has been removed by the main signal component remover.
    Type: Application
    Filed: September 23, 2020
    Publication date: January 25, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo IGARASHI, Masamichi FUJIWARA, Takuya KANAI
  • Patent number: 11870497
    Abstract: An optical reception device including: a local light transmission unit configured to generate a plurality of local lights having different wavelengths, select a local light having a wavelength that is close to the wavelength of a received optical signal from among the plurality of generated local lights having different wavelengths, and transmit the selected local light to a coherent receiver; a demultiplexing unit configured to demultiplex a received optical signal and transmit the demultiplexed optical signal to the coherent receiver via a first path; and a wavelength detection unit configured to input the optical signal demultiplexed by the demultiplexing unit via a second path, split the input optical signal into different paths according to wavelengths by using a wavelength multiplexer/demultiplexer, and output, to the local light transmission unit, a control signal for causing the local light transmission unit to output a local light having a frequency that corresponds to a path in which the optical sig
    Type: Grant
    Filed: July 1, 2019
    Date of Patent: January 9, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo Igarashi, Takuya Kanai, Masamichi Fujiwara, Junichi Kani
  • Patent number: 11863211
    Abstract: An optical communication system configured with a station-side apparatus and a plurality of subscriber-side apparatuses in a bus network topology includes an optical amplification unit installed on a station side, and a drop unit configured to branch an optical signal and excitation light, wherein the optical amplification unit includes an amplifier configured to amplify a downlink signal, and an excitation light output unit configured to output the excitation light for amplifying an uplink signal to a communication path, and the drop unit changes a branching ratio in accordance with a wavelength of the optical signal so that a transmission loss of the excitation light with respect to a trunk fiber is reduced.
    Type: Grant
    Filed: March 4, 2020
    Date of Patent: January 2, 2024
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Ryo Igarashi, Masamichi Fujiwara, Kazutaka Hara, Takuya Kanai, Yasutaka Kimura, Atsuko Kawakita