Patents by Inventor Takuto Arai

Takuto Arai 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: 20240413905
    Abstract: An aspect of the present invention is a wireless communication system including an accommodation station device and a base station device connected to the accommodation station device through an optical transmission path and having n (n is an integer of 2 or more) antenna elements, wherein a plurality of optical signals having different wavelengths propagate through the optical transmission path, the wireless communication system including a prior information acquisition unit configured to execute prior information acquisition processing for acquiring, as prior information, dispersion phase difference information that is information including a dispersion phase difference that is a phase rotation amount difference generated between adjacent optical signals on a wavelength axis due to propagation of the optical signals through the optical transmission path, and a compensation phase shift unit configured to execute compensation phase shift processing for reducing a difference from a phase difference reference t
    Type: Application
    Filed: February 12, 2021
    Publication date: December 12, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Mizuki SUGA, Kota ITO, Takuto ARAI, Yushi SHIRATO, Naoki KITA
  • Publication number: 20240405910
    Abstract: A wireless communication method wherein among a signal processing function and a communication function provided by a wireless communication device, a centralized unit having a signal processing function transmits an optical signal having a form corresponding to a downstream radio signal to be a transmission target in the communication function, to a communication target radio unit which communicates with an external communication device among two or more radio units having a communication function connected to the centralized unit via an optical fiber, and performs beam forming control of the communication target radio unit, and the communication target radio unit, according to control of the centralized unit, communicates with the external communication device.
    Type: Application
    Filed: January 27, 2021
    Publication date: December 5, 2024
    Applicants: NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kota ITO, Mizuki SUGA, Takuto ARAI, Yushi SHIRATO, Daisei UCHIDA, Naoki KITA, Takeshi ONIZAWA
  • Publication number: 20240372611
    Abstract: According to one aspect of the present invention, there is provided a radio communication device that performs communication with a terminal-side communication device having an antenna using an analog signal for transmitting information by a waveform of an amplitude or a phase of light to receive a signal received by the antenna and transmit a signal radiated by the antenna, the terminal-side communication device and the radio communication device being included in a radio communication system that performs radio communication with a communication target terminal via the antenna using time division duplex (TDD), the radio communication device including: an uplink delay adjustment unit configured to adjust a delay caused by propagation of an uplink signal that is a signal flowing from the terminal to the radio communication device via the antenna; and a downlink delay adjustment unit configured to adjust a delay caused by propagation of a downlink signal that is a signal flowing from the radio communication de
    Type: Application
    Filed: August 5, 2021
    Publication date: November 7, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuto ARAI, Hideki TOSHINAGA, Naoki KITA, Yushi SHIRATO, Daisei UCHIDA, Mizuki SUGA, Kota ITO
  • Publication number: 20240349072
    Abstract: A beam setting method includes a communication method prediction step of predicting a communication method performed on the basis of whether there is a line-of-sight between a first radio station device and a second radio station device; a first beam number setting step of setting the number of beams transmitted by a beam sweep, in which signals using formable beams are sequentially transmitted in a time-division manner, to a first constant, when the communication method prediction step predicts that communication is performed by the communication method using reflected waves; and a second beam number setting step of setting the number of beams transmitted by the beam sweep to a second constant smaller than the first constant, when the communication method prediction step predicts that communication is performed by the communication method using line-of-sight waves.
    Type: Application
    Filed: August 5, 2021
    Publication date: October 17, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Tatsuhiko IWAKUNI, Daisei UCHIDA, Takuto ARAI, Shuki WAI, Naoki KITA, Takeshi ONIZAWA
  • Publication number: 20240333344
    Abstract: A communication control method includes: a transmission step of simultaneously transmitting beam specifying signals including identical beam identifiers from a plurality of antennas to a wireless station for each of the beam identifiers by transmission beams associated with the beam identifiers; a reception step of receiving, by each of the plurality of antennas, a report signal including a selected beam identifier indicating a beam identifier selected on the basis of reception qualities of the beam specifying signals for the respective beam identifiers in the wireless station; and a selection step of selecting an antenna to be used for communication with the wireless station on the basis of reception qualities of the report signal respectively received by the plurality of antennas, and selecting a transmission beam associated with the selected beam identifier as a transmission beam to be used for communication with the wireless station.
    Type: Application
    Filed: July 14, 2021
    Publication date: October 3, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shuki WAI, Daisel UCHIDA, Tatsuhiko IWAKUNI, Takuto ARAI, Naoki KITA
  • Publication number: 20240292231
    Abstract: A determining method which is executed by a radio communication device includes a radio step of executing a radio communication, using two or more directional beams selected from a plurality of directional beams; and a determination step of determining which of line-of-sight waves and reflected waves is used for the executed radio communication, on the basis of an amount of variation in directions between the two or more directional beams used at different times. The determination step includes determining that the executed radio communication is radio communication using the reflected waves, when the amount of variation is equal to or greater than a threshold value.
    Type: Application
    Filed: August 6, 2021
    Publication date: August 29, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Tatsuhiko IWAKUNI, Daisel UCHIDA, Takuto ARAI, Shuki WAI, Naoki KITA
  • Publication number: 20240275491
    Abstract: A wireless communication method in a wireless communication system including an exchange device and a base station device configured to perform beamforming according to the control of the exchange device, in which: the exchange device performs beamforming control of the base station device by transmitting an optically modulated signal to the base station device via an optical transmission line, the optically modulated signal being generated by modulating an intensity of an optical signal on a basis of a transmission signal to be transmitted by controlling any combination of an optical wavelength, a frequency, and an optical polarization or controlling the frequency; and the base station device inputs an electrical signal based on the optically modulated signal to a beamforming circuit having an input port corresponding to the number of combinations of the optical wavelength, the frequency, and the optical polarization or the number of frequencies to perform beamforming in a direction corresponding to the inpu
    Type: Application
    Filed: May 17, 2021
    Publication date: August 15, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kota ITO, Mizuki SUGA, Takuto ARAI, Yushi SHIRATO, Naoki KITA
  • Publication number: 20240267122
    Abstract: A wireless communication method in a wireless communication system including an accommodation station device and a base station device that performs beam formation according to control of the accommodation station device, includes: transmitting an optical modulation signal generated by performing intensity modulation on an optical signal on the basis of a transmission signal to be transmitted to the base station device via an optical transmission line by the accommodation station device controlling any combination of a light wavelength, a frequency, or an optical polarized wave, or a plurality of frequencies or a plurality of light wavelengths, to perform beamforming control of the base station device; transmitting the optical modulation signal after dispersion compensation is performed in an electrical domain or an optical domain in the accommodation station device or performing dispersion compensation on the optical modulation signal on the optical transmission line; and inputting, by the base station devic
    Type: Application
    Filed: June 23, 2021
    Publication date: August 8, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kota ITO, Mizuki SUGA, Takuto ARAI, Yushi SHIRATO, Naoki KITA
  • Publication number: 20240259817
    Abstract: One aspect of the present invention is a control method in a wireless communication system including a plurality of distributed antennas that perform wireless communication with a user terminal, and a plurality of signal processing units that are connected to the plurality of distributed antennas and perform signal processing, the control method including: a setting unit that sets reference information for leveling loads of the plurality of signal processing units for each of the plurality of signal processing units; an acquisition step of acquiring load information indicating a load of a signal processing unit; and an assignment step of assigning the signal processing unit as a connection destination of the distributed antenna on the basis of the load information acquired in the acquisition step and the reference information, and leveling the loads of the plurality of signal processing units.
    Type: Application
    Filed: May 17, 2021
    Publication date: August 1, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuto ARAI, Daisei UCHIDA, Tatsuhiko IWAKUNI, Shuki WAI
  • Publication number: 20240259098
    Abstract: A wireless communication method in a wireless communication system including an exchange device and a base station device that performs beamforming according to the control of the exchange device, in which: the exchange device performs beamforming control of the base station device by transmitting an optically modulated signal to the base station device via an optical transmission line, the optically modulated signal being generated by modulating an intensity of an optical signal on a basis of a transmission signal to be transmitted by controlling any combination of an optical wavelength, a frequency, and an optical polarization or controlling the frequency; and the base station device performs beamforming in a direction in which a wireless signal radiated from an antenna to which an electrical signal based on the optically modulated signal has been input is reflected by a reflector or is transmitted through a lens among antennas corresponding to the number of combinations of the optical wavelength, the frequ
    Type: Application
    Filed: May 17, 2021
    Publication date: August 1, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kota ITO, Mizuki SUGA, Takuto ARAI, Yushi SHIRATO, Naoki KITA
  • Publication number: 20240250718
    Abstract: One aspect of the present invention is a control method in a wireless communication system including a plurality of distributed antennas that perform wireless communication with a user terminal, and a plurality of signal processing units that are connected to the plurality of distributed antennas and perform signal processing, the control method including: an initial assignment step of assigning a distributed antenna to be connected to a signal processing unit; an acquisition step of acquiring load information indicating loads of the signal processing unit; a determination step of determining whether to reassign the distributed antenna to be connected to the signal processing unit on the basis of the load information acquired in the acquisition step; and a reassignment step of performing reassignment and leveling loads of the plurality of signal processing units when it is determined to reassign in the determination step.
    Type: Application
    Filed: May 17, 2021
    Publication date: July 25, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuto ARAI, Daisei UCHIDA, Tatsuhiko IWAKUNI, Shuki WAI
  • Patent number: 11936441
    Abstract: A FrontHaul Multiplexer (FHM) for relaying communications between a signal processing device and a plurality of radio devices includes a storage unit that stores a table in which device identification information of each of the plurality of radio devices is associated with beam identification information assigned to the radio device; a scheduling information reception unit that receives, from the signal processing device, scheduling information of a user terminal performing radio communications with the plurality of radio devices; a determination unit that acquires from the table the device identification information associated with the beam identification information of uplink included in the scheduling information and then determines from the acquired device identification information the radio device in charge of the user terminal; and a transmission unit that transmits to the signal processing device an uplink signal transmitted from the determined radio device.
    Type: Grant
    Filed: November 9, 2018
    Date of Patent: March 19, 2024
    Assignee: NTT DOCOMO, INC.
    Inventors: Takashi Kosugi, Tatsuro Yajima, Takuto Arai, Yuta Sagae, Akihito Hanaki, Hidekazu Shimodaira, Masahiro Fujii, Yoshiaki Ofuji
  • Publication number: 20240088960
    Abstract: A wireless communication apparatus includes a terminal selection unit that selects one or more user terminals, a prediction unit that derives a prediction value of an interference amount of a stream group transmitted from a plurality of antennas for the selected one or more user terminals, a collection unit that, when the prediction value of the interference amount is less than a threshold value, collects reception power values of streams included in the stream group from the selected one or more user terminals, an antenna selection unit that selects the plurality of streams in descending order of reception power values and selecting the plurality of antennas associated with the plurality of selected streams, and a transmission unit that transmits the plurality of selected streams by beam forming using the plurality of selected antennas.
    Type: Application
    Filed: February 2, 2021
    Publication date: March 14, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takuto ARAI, Daisei UCHIDA, Tatsuhiko IWAKUNI, Shuki WAI
  • Publication number: 20240063907
    Abstract: A radio communication method performed by a radio communication device includes an inverse fast Fourier transform step of performing inverse fast Fourier transform on a digital electric signal associated with a downlink radio signal, a digital-to-analogue conversion step of converting the digital electric signal subjected to the inverse fast Fourier transform into a first analogue electric signal, an electro-optic conversion step of converting the first analogue electric signal into an optical signal, a step of transmitting the optical signal, a photoelectric conversion step of converting the transmitted optical signal into a second analogue electric signal, and a step of transmitting the downlink radio signal corresponding to the second analogue electric signal.
    Type: Application
    Filed: January 22, 2021
    Publication date: February 22, 2024
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kota ITO, Mizuki SUGA, Takuto ARAI, Yushi SHIRATO, Daisei UCHIDA, Naoki KITA, Takeshi ONIZAWA
  • Publication number: 20230239824
    Abstract: A communication device constitutes a management node that manages at least one of a first base station and a second base station provided on fronthaul. The communication device includes an acquisition unit that acquires a delay profile of the second base station, a control unit that determines a window parameter used to specify at least one of a Reception window and a Transmission window used in the first base station based on the delay profile of the second base station and a delay parameter defined by the fronthaul, and a notification unit that notifies the first base station of the window parameter.
    Type: Application
    Filed: January 17, 2020
    Publication date: July 27, 2023
    Applicant: NTT DOCOMO, INC.
    Inventors: Kunihiko Teshima, Daisuke Hiratsuka, Takuto Arai, Anil Umesh
  • Publication number: 20220014236
    Abstract: An FHM for relaying communications between a signal processing device and a plurality of radio devices comprises: a storage unit that stores a table in which device identification information of each of the plurality of radio devices is associated with beam identification information assigned to the radio device; a scheduling information reception unit that receives, from the signal processing device, scheduling information of a user terminal performing radio communications with the plurality of radio devices; a determination unit that acquires from the table the device identification information associated with the beam identification information of uplink included in the scheduling information and then determines from the acquired device identification information the radio device in charge of the user terminal; and a transmission unit that transmits to the signal processing device an uplink signal transmitted from the determined radio device.
    Type: Application
    Filed: November 9, 2018
    Publication date: January 13, 2022
    Applicant: NTT DOCOMO, INC.
    Inventors: Takashi Kosugi, Tatsuro Yajima, Takuto Arai, Yuta Sagae, Akihito Hanaki, Hidekazu Shimodaira, Masahiro Fujii, Yoshiaki Ofuji