Patents by Inventor Takuya Ohara

Takuya Ohara 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: 20220006722
    Abstract: A transmission apparatus performs communication with a transmission side transmission apparatus via a transmission path of an active system and a transmission path of a standby system. The transmission apparatus includes: a memory configured to have a capacity that is as large as delay caused due to a maximum path difference between the transmission path of the active system and the transmission path of the standby system is allowable; and a memory connection control unit configured to switch connection of the memory and cause a signal of the transmission path of the active system or the transmission path of the standby system to be accumulated in the memory.
    Type: Application
    Filed: November 7, 2019
    Publication date: January 6, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kei KITAMURA, Fumikazu INUZUKA, Akira HIRANO, Masahito TOMIZAWA, Takuya OHARA
  • Publication number: 20200314715
    Abstract: When being connected to a macro cell (S-MeNB) and a small cell (SeNB), a user equipment device performs a pre-handover process of disconnecting the connection with the SeNB before a handover process of switching a macro cell connected with the UE from the macro cell (S-MeNB) that is a moving source to a macro cell (T-MeNB) that is a moving destination along with moving of the UE, and after the handover process, performs a post-handover process of reestablishing the connection with the SeNB.
    Type: Application
    Filed: June 17, 2020
    Publication date: October 1, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takuya OHARA, Taisei Suemitsu, Mitsuru Mochizuki, Kuniyuki Suzuki, Masayuki Nakazawa, Daisuke Hiramatsu
  • Patent number: 10743227
    Abstract: When being connected to a macro cell (S-MeNB) and a small cell (SeNB), a user equipment device performs a pre-handover process of disconnecting the connection with the SeNB before a handover process of switching a macro cell connected with the UE from the macro cell (S-MeNB) that is a moving source to a macro cell (T-MeNB) that is a moving destination along with moving of the UE, and after the handover process, performs a post-handover process of reestablishing the connection with the SeNB.
    Type: Grant
    Filed: March 16, 2015
    Date of Patent: August 11, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takuya Ohara, Taisei Suemitsu, Mitsuru Mochizuki, Kuniyuki Suzuki, Masayuki Nakazawa, Daisuke Hiramatsu
  • Publication number: 20190144974
    Abstract: A copper alloy has a composition including 0.05 mass % or more and 0.70 mass % or less of Co; 0.02 mass % or more and 0.20 mass % or less of P; 0.005 mass % or more and 0.70 mass % or less of Sn, one or more of B, Cr, and Zr; and furthermore, a Cu balance containing inevitable impurities, wherein X, Y, and Z satisfy the following Expression (1): 1?(X/5)+(Y/50)+(Z/100) and Expression (2): X+Y+Z?1,000, in case where an amount of B is represented by X (massppm), an amount of Cr is represented by Y (massppm), and an amount of Zr is represented by Z (massppm).
    Type: Application
    Filed: June 23, 2017
    Publication date: May 16, 2019
    Inventors: Yuusuke Enami, Toshio Sakamoto, Hitoshi Nakamoto, Keiichiro Oishi, Atsushi Sugahara, Chikara Yamashita, Takuya Ohara
  • Patent number: 10250348
    Abstract: In the optical transport system a transport frame generator divides a transport frame accommodating plural client signals into plural transmission signals. Subcarrier transmission units convert the signals into optical signals using different optical carriers and transmit the converted optical signals. Subcarrier reception units receive the transmitted optical signals and convert the optical signals into reception signals. A transport frame termination unit combines the reception signals to restore the transport frame. A time-demultiplexing processor time-demultiplexes the restored transport frame to be separated into the client signals. A time slot control unit determines a new time slot allocation when time-multiplexing the client signals in the transport frame and stops supply of electric power to a subcarrier transmission unit and a subcarrier reception unit that transmit and receive an optical signal to which the client signals are not allocated.
    Type: Grant
    Filed: November 26, 2015
    Date of Patent: April 2, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yoshiaki Yamada, Kengo Shintaku, Takuya Ohara, Kei Kitamura, Takashi Kotanigawa, Takafumi Hamano, Kaoru Arai, Masahiro Yokota, Hideki Maeda
  • Patent number: 10230457
    Abstract: A framer in a transmission device allocates plural optical channel time slots to a plurality of logical prioritized paths. It allocates received client signals to the allocated time slots, and transmits the client signals by a plurality of optical subcarriers that use a plurality of optical wavelengths corresponding to the plurality of time slots. The framer includes: a time slot allocation unit that, in a case where an optical wavelength corresponding to a time slot allocated to a logical path having a high transmission priority is not used, allocates at least one of the plurality of time slots to the logical path having the high transmission priority while the time slot corresponding to the unused optical wavelength is avoided, to change the time slot allocated to the logical path having the high transmission priority.
    Type: Grant
    Filed: November 27, 2015
    Date of Patent: March 12, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kei Kitamura, Takafumi Hamano, Takashi Kotanigawa, Kaoru Arai, Masahiro Yokota, Hideki Maeda, Yoshiaki Yamada, Takuya Ohara, Kengo Shintaku
  • Patent number: 10181921
    Abstract: A framer in a transmission device that allocates time slots of an optical channel to a logical path, divides client signals received via the logical path to the time slots allocated to the logical path, and transmits the client signals by a plurality of optical subcarriers using optical wavelengths correlated with the time slots includes: a time slot allocating unit configured to perform a process of reducing a transmission band of the logical path when some of the optical wavelengths are unavailable and changing the time slots allocated to the logical path depending on the reduced transmission band to avoid using the time slots corresponding to the unavailable optical wavelengths.
    Type: Grant
    Filed: November 26, 2015
    Date of Patent: January 15, 2019
    Assignee: Nippon Telegraph And Telephone Corporation
    Inventors: Masahiro Yokota, Takafumi Hamano, Takashi Kotanigawa, Kaoru Arai, Kei Kitamura, Hideki Maeda, Yoshiaki Yamada, Takuya Ohara, Kengo Shintaku
  • Patent number: 10122462
    Abstract: A transport apparatus includes: a client signal transceiving unit which transceives a client signal; a line signal transceiving unit which performs electric-optic conversion on a line signal to be transmitted, transmits an optical line signal, performs optic-electric conversion on a received line signal, and outputs an electrical line signal; and a plurality of signal processing units which perform signal processing on the client signal to generate the line signal to be transmitted and perform signal processing on the electrical line signal to generate the client signal.
    Type: Grant
    Filed: November 19, 2014
    Date of Patent: November 6, 2018
    Assignee: Nippon Telegraph And Telephone Corporation
    Inventors: Takuya Ohara, Kei Kitamura, Yoshiaki Kisaka, Shigeki Aisawa, Masahiro Suzuki, Etsushi Yamazaki, Tomoyoshi Kataoka, Masahito Tomizawa, Yoshiaki Yamada, Mitsuhiro Teshima, Akira Hirano
  • Patent number: 10063321
    Abstract: There is provided a tray which is connected to a plurality of transmitters that multicarrier-transmit a plurality of parallel signals by optical subcarriers. The framer selects time slots to be allocated to a path to be accommodated such that the number of optical subcarriers corresponding to the time slots satisfies a predetermined condition on the basis of empty time slots which are specified by path accommodation information indicating a correspondence between paths allocated to a client signal and time slots in a signal frame and the optical subcarriers corresponding to the empty time slots indicated by time slot information indicating a correspondence between the time slots and the optical subcarriers, and sets the selected time slot in the path accommodation information. The framer sets a client signal to the time slots on the basis of the path accommodation information.
    Type: Grant
    Filed: November 27, 2015
    Date of Patent: August 28, 2018
    Assignee: Nippon Telegraph And Telephone Corporation
    Inventors: Kei Kitamura, Takashi Kotanigawa, Takafumi Hamano, Kaoru Arai, Masahiro Yokota, Hideki Maeda, Yoshiaki Yamada, Takuya Ohara, Kengo Shintaku
  • Publication number: 20180176839
    Abstract: When being connected to a macro cell (S-MeNB) and a small cell (SeNB), a user equipment device performs a pre-handover process of disconnecting the connection with the SeNB before a handover process of switching a macro cell connected with the UE from the macro cell (S-MeNB) that is a moving source to a macro cell (T-MeNB) that is a moving destination along with moving of the UE, and after the handover process, performs a post-handover process of reestablishing the connection with the SeNB.
    Type: Application
    Filed: March 16, 2015
    Publication date: June 21, 2018
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takuya OHARA, Taisei SUEMITSU, Mitsuru MOCHIZUKI, Kuniyuki SUZUKI, Masayuki NAKAZAWA, Daisuke HIRAMATSU
  • Publication number: 20170366288
    Abstract: A framer in a transmission device that allocates time slots of an optical channel to a logical path, divides client signals received via the logical path to the time slots allocated to the logical path, and transmits the client signals by a plurality of optical suhcarriers using optical wavelengths correlated with the time slots includes: a time slot allocating unit configured to perform a process of reducing a transmission band of the logical path when some of the optical wavelengths are unavailable and changing the time slots allocated to the logical path depending on the reduced transmission band to avoid using the time slots corresponding to the unavailable optical wavelengths.
    Type: Application
    Filed: November 26, 2015
    Publication date: December 21, 2017
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masahiro YOKOTA, Takafumi HAMANO, Takashi KOTANIGAWA, Kaoru ARAI, Kei KITAMURA, Hideki MAEDA, Yoshiaki YAMADA, Takuya OHARA, Kengo SHINTAKU
  • Publication number: 20170324496
    Abstract: In the optical transport system a transport frame generator divides a transport frame accommodating plural client signals into plural transmission signals. Subcarrier transmission units convert the signals into optical signals using different optical carriers and transmit the converted optical signals. Subcarrier reception units receive the transmitted optical signals and convert the optical signals into reception signals. A transport frame termination unit combines the reception signals to restore the transport frame. A time-demultiplexing processor time-demultiplexes the restored transport frame to be separated into the client signals. A time slot control unit determines a new time slot allocation when time-multiplexing the client signals in the transport frame and stops supply of electric power to a subcarrier transmission unit and a subcarrier reception unit that transmit and receive an optical signal to which the client signals are not allocated.
    Type: Application
    Filed: November 26, 2015
    Publication date: November 9, 2017
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yoshiaki YAMADA, Kengo SHINTAKU, Takuya OHARA, Kei KITAMURA, Takashi KOTANIGAWA, Takafumi HAMANO, Kaoru ARAI, Masahiro YOKOTA, Hideki MAEDA
  • Publication number: 20170324472
    Abstract: A framer in a transmission device allocates plural optical channel time slots to a plurality of logical prioritized paths. It allocates received client signals to the allocated time slots, and transmits the client signals by a plurality of optical subcarriers that use a plurality of optical wavelengths corresponding to the plurality of time slots. The framer includes: a time slot allocation unit that, in a case where an optical wavelength corresponding to a time slot allocated to a logical path having a high transmission priority is not used, allocates at least one of the plurality of time slots to the logical path having the high transmission priority while the time slot corresponding to the unused optical wavelength is avoided, to change the time slot allocated to the logical path having the high transmission priority.
    Type: Application
    Filed: November 27, 2015
    Publication date: November 9, 2017
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kei KITAMURA, Takafumi HAMANO, Takashi KOTANIGAWA, Kaoru ARAI, Masahiro YOKOTA, Hideki MAEDA, Yoshiaki YAMADA, Takuya OHARA, Kengo SHINTAKU
  • Publication number: 20170257169
    Abstract: There is provided a tray which is connected to a plurality of transmitters that multicarrier-transmit a plurality of parallel signals by optical subcarriers. The framer selects time slots to be allocated to a path to be accommodated such that the number of optical subcarriers corresponding to the time slots satisfies a predetermined condition on the basis of empty time slots which are specified by path accommodation information indicating a correspondence between paths allocated to a client signal and time slots in a signal frame and the optical subcarriers corresponding to the empty time slots indicated by time slot information indicating a correspondence between the time slots and the optical subcarriers, and sets the selected time slot in the path accommodation information. The framer sets a client signal to the time slots on the basis of the path accommodation information.
    Type: Application
    Filed: November 27, 2015
    Publication date: September 7, 2017
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kei KITAMURA, Takashi KOTANIGAWA, Takafumi HAMANO, Kaoru ARAI, Masahiro YOKOTA, Hideki MAEDA, Yoshiaki YAMADA, Takuya OHARA, Kengo SHINTAKU
  • Patent number: 9667350
    Abstract: The optical receiving device with phase compensation apparatus uses coherent opto-electric conversion and is designed for receiving phase- or quadrature-amplitude-modulated optical signals. The phase compensation apparatus includes following elements: a carrier-phase estimation unit that estimates carrier phase errors in a received symbol string; a gain adjustment unit that adjusts weighting of each symbols in phase error evaluation performed in the carrier-phase adjustment unit; a phase-cycle-slip reduction unit with a phase-cycle-slip detector using statistical processing performed on the output symbols from the carrier-phase estimation unit; and a phase compensation circuit that compensates carrier phase errors of the received signal using an output from the carrier phase estimation unit.
    Type: Grant
    Filed: January 24, 2014
    Date of Patent: May 30, 2017
    Assignee: Nippon Telegraph And Telephone Corporation
    Inventors: Kengo Horikoshi, Kohki Shibahara, Etsushi Yamazaki, Mitsuteru Yoshida, Koichi Ishihara, Takayuki Kobayashi, Yoshiaki Kisaka, Takuya Ohara, Masahito Tomizawa, Tomoyoshi Kataoka
  • Publication number: 20170111116
    Abstract: A transport apparatus includes: a client signal transceiving unit which transceives a client signal; a line signal transceiving unit which performs electric-optic conversion on a line signal to be transmitted, transmits an optical line signal, performs optic-electric conversion on a received line signal, and outputs an electrical line signal; and a plurality of signal processing units which perform signal processing on the client signal to generate the line signal to be transmitted and perform signal processing on the electrical line signal to generate the client signal.
    Type: Application
    Filed: November 19, 2014
    Publication date: April 20, 2017
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuya OHARA, Kei KITAMURA, Yoshiaki KISAKA, Shigeki AISAWA, Masahiro SUZUKI, Etsushi YAMAZAKI, Tomoyoshi KATAOKA, Masahito TOMIZAWA, Yoshiaki YAMADA, Mitsuhiro TESHIMA, Akira HIRANO
  • Patent number: 9438365
    Abstract: A client signal mapping circuit for accommodating a client signal in a transmission frame, including: a buffer unit configured to temporarily store the client signal; a buffer used amount monitoring unit configured to report a used amount of the buffer unit; a stuff processing determination unit configured to compare the used amount of the buffer unit with a predetermined reference value, and a pseudo random sequence signal and the comparison result; an overhead insertion unit configured to add an overhead to the client signal read from the buffer unit to form a transmission frame; and a reading control unit configured to perform control for reading the client signal from the buffer unit based on determination by the stuff processing determination unit.
    Type: Grant
    Filed: August 27, 2015
    Date of Patent: September 6, 2016
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masahiro Suzuki, Takuya Ohara, Takashi Ono, Shigeki Aisawa, Masahito Tomizawa
  • Publication number: 20160006525
    Abstract: A client signal mapping circuit for accommodating a client signal in a transmission frame, including: a buffer unit configured to temporarily store the client signal; a buffer used amount monitoring unit configured to report a used amount of the buffer unit; a stuff processing determination unit configured to compare the used amount of the buffer unit with a predetermined reference value, and a pseudo random sequence signal and the comparison result; an overhead insertion unit configured to add an overhead to the client signal read from the buffer unit to form a transmission frame; and a reading control unit configured to perform control for reading the client signal from the buffer unit based on determination by the stuff processing determination unit.
    Type: Application
    Filed: August 27, 2015
    Publication date: January 7, 2016
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masahiro SUZUKI, Takuya OHARA, Takashi ONO, Shigeki AlSAWA, Masahito TOMIZAWA
  • Publication number: 20150333838
    Abstract: An optical receiving device receives an optical signal that has been modulated by means of phase modulation or quadrature amplitude modulation, converts the received optical signal into an electrical signal using coherent detection, and performs phase compensation on the converted received signal, and includes: a carrier phase estimation unit that estimates carrier phase errors in a received symbol string obtained from the received signal; a gain adjustment unit that performs gain adjustment on symbols input into the carrier phase adjustment unit; a phase cycle slip reduction unit that, by performing statistical processing on an output from the carrier phase estimation unit, detects general noise that causes a phase cycle slip, and reduces the phase cycle slip; and a phase compensation circuit that compensates carrier phase errors contained in the received signal using an output from the carrier phase estimation unit.
    Type: Application
    Filed: January 24, 2014
    Publication date: November 19, 2015
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kengo HORIKOSHI, Kohki SHIBAHARA, Etsushi YAMAZAKI, Mitsuteru YOSHIDA, Koichi ISHIHARA, Takayuki KOBAYASHI, Yoshiaki KISAKA, Takuya OHARA, Masahito TOMIZAWA, Tomoyoshi KATAOKA
  • Patent number: 9160479
    Abstract: A client signal mapping circuit for accommodating a client signal in a transmission frame, including: a buffer unit configured to temporarily store the client signal; a buffer used amount monitoring unit configured to report a used amount of the buffer unit; a stuff processing determination unit configured to compare the used amount of the buffer unit with a predetermined reference value, and a pseudo random sequence signal and the comparison result; an overhead insertion unit configured to add an overhead to the client signal read from the buffer unit to form a transmission frame; and a reading control unit configured to perform control for reading the client signal from the buffer unit based on determination by the stuff processing determination unit.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: October 13, 2015
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masahiro Suzuki, Takuya Ohara, Takashi Ono, Shigeki Aisawa, Masahito Tomizawa