Patents by Inventor Nobukazu Fudaba

Nobukazu Fudaba 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: 9961645
    Abstract: A base station device includes: an acquisition unit that acquires reception quality of each of a plurality of carriers from a terminal device that performs primary cell connection for transmission and reception of a control channel signal using a carrier whose reception quality is most preferable; a decision unit that decides an amount of increase in transmission power of one of the carriers based on the reception quality acquired by the acquisition unit; a determination unit that estimates whether switching of the primary cell connection occurs in case of increasing the transmission power by the amount of increase and determines whether to increase the transmission power according to the estimation result; and an instruction unit that instructs a transmission unit to increase the transmission power of the carrier by the amount of increase when the determination unit determines to increase the transmission power.
    Type: Grant
    Filed: February 2, 2016
    Date of Patent: May 1, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Kotaro Shiizaki, Junji Otonari, Nobukazu Fudaba
  • Publication number: 20180007700
    Abstract: A control apparatus coupled to a plurality of base station apparatuses, the control apparatus including a memory and a processor configured to receive base station information transmitted from a terminal apparatus that communicates with one of the plurality of base station apparatuses, the base station information including measurement results for each of a plurality of signals received with reception quality equal to or higher than a reference value at the terminal apparatus, each of the plurality of signals being transmitted from the plurality of base station apparatuses, and perform control to improve reception quality of at least one of the plurality of signals transmitted from the plurality of base station apparatuses other than a specified base station apparatus when the base station information does not satisfy a predetermined condition, the specified base station apparatus being a base station apparatus to which the terminal apparatus is being coupled.
    Type: Application
    Filed: June 26, 2017
    Publication date: January 4, 2018
    Applicant: FUJITSU LIMITED
    Inventor: Nobukazu Fudaba
  • Patent number: 9730126
    Abstract: A base station serving terminals, the base station including: a memory, and a processor coupled to the memory and configured to: select a terminal among the served terminals based on reception powers or reception qualities at the served terminals, when a number of the served terminals exceeds a threshold, determine an amount of change in transmission parameter so that a reception quality at the selected terminal from another base station satisfies a certain condition in case where a handover of the selected terminal to the other base station is performed, the other base station being selected based on the reception powers or the reception qualities, perform the handover of the selected terminal to the other base station, and change the transmission parameter by the determined amount of change.
    Type: Grant
    Filed: June 3, 2014
    Date of Patent: August 8, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Nobukazu Fudaba, Dai Kimura, Michiko Anbe
  • Publication number: 20160373988
    Abstract: A base station including: a processor configured to: form a plurality of cells, each of the plurality of cells having each of a plurality of different frequency bands, obtain capability information and state information when a number of a plurality of terminals coupling to a specified cell of the plurality of cells exceeds a predetermined threshold, the capability information indicating each capability of each of the plurality of terminals for coupling to a different cell of the plurality of cells, the state information indicating each state of each coupling between each of the plurality of terminals and the different cell, select a first terminal from among the plurality of terminals based on the first information and the second information, a coupling between the first terminal and the specified cell being to be released, and switch a cell coupled by the first terminal, from the specified cell to the different cell.
    Type: Application
    Filed: June 13, 2016
    Publication date: December 22, 2016
    Inventor: Nobukazu FUDABA
  • Publication number: 20160278024
    Abstract: A base station device includes: an acquisition unit that acquires reception quality of each of a plurality of carriers from a terminal device that performs primary cell connection for transmission and reception of a control channel signal using a carrier whose reception quality is most preferable; a decision unit that decides an amount of increase in transmission power of one of the carriers based on the reception quality acquired by the acquisition unit; a determination unit that estimates whether switching of the primary cell connection occurs in case of increasing the transmission power by the amount of increase and determines whether to increase the transmission power according to the estimation result; and an instruction unit that instructs a transmission unit to increase the transmission power of the carrier by the amount of increase when the determination unit determines to increase the transmission power.
    Type: Application
    Filed: February 2, 2016
    Publication date: September 22, 2016
    Applicant: FUJITSU LIMITED
    Inventors: Kotaro Shiizaki, Junji Otonari, Nobukazu Fudaba
  • Patent number: 9414277
    Abstract: A base station includes a first determination unit, a calculation unit, and a control unit. The first determination unit determines whether a terminal in connection with the base station is a terminal passing a cell of the base station. The calculation unit calculates handover frequency of the terminal determined as the passing terminal by the first determination unit. The control unit controls transmission power in accordance with the frequency calculated by the calculation unit.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: August 9, 2016
    Assignee: FUJITSU LIMITED
    Inventor: Nobukazu Fudaba
  • Patent number: 9380509
    Abstract: A base station includes an acquiring unit, a deciding unit, and a control unit. The acquiring unit acquires measurement information related to wireless communication quality of a mobile station. The deciding unit decides, by using the measurement information acquired by the acquiring unit and information that is used to control priority of a handover destination cell indicated by a control station, a cell to which the mobile station is handed over. The control unit hands over the mobile station to the cell decided by the deciding unit.
    Type: Grant
    Filed: December 17, 2014
    Date of Patent: June 28, 2016
    Assignee: FUJITSU LIMITED
    Inventor: Nobukazu Fudaba
  • Patent number: 9263994
    Abstract: An amplifying device including: a first amplifier configured to generate a first output signal by amplifying an input signal, a second amplifier configured to generate a second output signal by amplifying the first output signal, and a processor configured to perform a first compensation by compensating a distortion for the second amplifier in accordance with the first output signal and the second output signal.
    Type: Grant
    Filed: January 15, 2014
    Date of Patent: February 16, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Nobukazu Fudaba, Hiroyoshi Ishikawa, Yuichi Utsunomiya, Toshio Kawasaki, Kazuo Nagatani
  • Publication number: 20150296432
    Abstract: A base station includes a first determination unit, a calculation unit, and a control unit. The first determination unit determines whether a terminal in connection with the base station is a terminal passing a cell of the base station. The calculation unit calculates handover frequency of the terminal determined as the passing terminal by the first determination unit. The control unit controls transmission power in accordance with the frequency calculated by the calculation unit.
    Type: Application
    Filed: March 24, 2015
    Publication date: October 15, 2015
    Inventor: Nobukazu Fudaba
  • Patent number: 9143965
    Abstract: A wireless station includes: a receiver configured to receive information on a reception quality from a wireless communication apparatus that is connected to the wireless station; and a processor coupled to the receiver and configured to: calculate, based on the reception quality, an index value indicating a difference between a signal-to-interference ratio in the wireless communication apparatus and transmission power of the wireless station, calculate a statistical amount of the index value calculated with regard to each of the plurality of reception qualities, and determine the transmission power in accordance with the statistical amount.
    Type: Grant
    Filed: January 10, 2014
    Date of Patent: September 22, 2015
    Assignee: FUJITSU LIMITED
    Inventors: Nobukazu Fudaba, Junji Otonari
  • Patent number: 9100263
    Abstract: A distortion compensation apparatus for performing distortion compensation processing by applying the inverse properties of distortion properties of the power amplifier to a transmission signal to be input to a power amplifier, includes a plurality of distortion compensation coefficient storage units configured to store a plurality of distortion compensation coefficients used for the distortion compensation processing, an offset correction processing unit configured to subject the distortion compensation coefficient stored in each of the plurality of distortion compensation coefficient storage units to offset correction processing, and to generate distortion compensation coefficients in the case that the offset correction processing has not been performed, corresponding to plurality of distortion compensation coefficient storage units, in a pseudo manner and a distortion compensation processing unit configured to subject the transmission signal to the distortion compensation processing based on the distortion
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: August 4, 2015
    Assignee: FUJITSU LIMITED
    Inventors: Yuichi Utsunomiya, Hiroyoshi Ishikawa, Nobukazu Fudaba, Kazuo Nagatani
  • Publication number: 20150208312
    Abstract: A base station includes an acquiring unit, a deciding unit, and a control unit. The acquiring unit acquires measurement information related to wireless communication quality of a mobile station. The deciding unit decides, by using the measurement information acquired by the acquiring unit and information that is used to control priority of a handover destination cell indicated by a control station, a cell to which the mobile station is handed over. The control unit hands over the mobile station to the cell decided by the deciding unit.
    Type: Application
    Filed: December 17, 2014
    Publication date: July 23, 2015
    Inventor: Nobukazu Fudaba
  • Patent number: 8933752
    Abstract: A power amplifier apparatus that includes a processor that performs a first distortion compensation processing on an input signal using a distortion compensation coefficient to obtain a first signal and an amplifier that amplifies the first signal. The processor performs a second distortion compensation processing the amplified signal using the distortion compensation coefficient to obtain a second signal and updates the distortion compensation coefficient to enable convergence between the first signal and the second signal.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: January 13, 2015
    Assignee: Fujitsu Limited
    Inventors: Kazuo Nagatani, Yuichi Utsunomiya, Nobukazu Fudaba, Hiroyoshi Ishikawa, Hajime Hamada
  • Publication number: 20140364125
    Abstract: A base station serving terminals, the base station including: a memory, and a processor coupled to the memory and configured to: select a terminal among the served terminals based on reception powers or reception qualities at the served terminals, when a number of the served terminals exceeds a threshold, determine an amount of change in transmission parameter so that a reception quality at the selected terminal from another base station satisfies a certain condition in case where a handover of the selected terminal to the other base station is performed, the other base station being selected based on the reception powers or the reception qualities, perform the handover of the selected terminal to the other base station, and change the transmission parameter by the determined amount of change.
    Type: Application
    Filed: June 3, 2014
    Publication date: December 11, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Nobukazu FUDABA, Dai KIMURA, Michiko ANBE
  • Publication number: 20140273875
    Abstract: A wireless station includes: a receiver configured to receive information on a reception quality from a wireless communication apparatus that is connected to the wireless station; and a processor coupled to the receiver and configured to: calculate, based on the reception quality, an index value indicating a difference between a signal-to-interference ratio in the wireless communication apparatus and transmission power of the wireless station, calculate a statistical amount of the index value calculated with regard to each of the plurality of reception qualities, and determine the transmission power in accordance with the statistical amount.
    Type: Application
    Filed: January 10, 2014
    Publication date: September 18, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Nobukazu Fudaba, Junji Otonari
  • Patent number: 8787487
    Abstract: A distortion compensation device which reduces a distortion of an amplifier which is added to an output signal of the amplifier, the distortion compensation device including: a plurality of distortion compensation coefficient storage circuits which stores a plurality of distortion compensation coefficients and outputs the distortion compensation coefficients according to an amplitude of an input signal of the amplifier, a distortion compensating processing circuit which adds the distortion compensation coefficient output from each of the plurality of distortion compensation coefficient storage circuits to the input signal of the amplifier, and a distortion compensation coefficient updating circuit which performs weighting processing on the distortion compensation coefficient output from each of the plurality of distortion compensation coefficient storage circuits to reduce the distortion compensation coefficient and which calculates an update value of the distortion compensation coefficient by using the disto
    Type: Grant
    Filed: May 2, 2012
    Date of Patent: July 22, 2014
    Assignee: Fujitsu Limited
    Inventors: Kazuo Nagatani, Hiroyoshi Ishikawa, Nobukazu Fudaba, Yuichi Utsunomiya
  • Publication number: 20140197885
    Abstract: An amplifying device including: a first amplifier configured to generate a first output signal by amplifying an input signal, a second amplifier configured to generate a second output signal by amplifying the first output signal, and a processor configured to perform a first compensation by compensating a distortion for the second amplifier in accordance with the first output signal and the second output signal.
    Type: Application
    Filed: January 15, 2014
    Publication date: July 17, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Nobukazu FUDABA, Hiroyoshi ISHIKAWA, Yuichi UTSUNOMIYA, Toshio KAWASAKI, Kazuo NAGATANI
  • Patent number: 8737937
    Abstract: A distortion compensation apparatus includes an amplifying unit, a plurality of distortion compensation coefficient storage units, a first address generating unit, a second address generating unit, and a distortion compensating unit. The amplifying unit amplifies an input signal. A plurality of distortion compensation coefficient storage units store the distortion compensation coefficients for compensating for the distortion of the amplifying unit by being associated with two different addresses. The first address generating unit generates a first address based on the current input signal. The second address generating unit generates a second address different from the first address based on the previous input signal.
    Type: Grant
    Filed: July 5, 2012
    Date of Patent: May 27, 2014
    Assignee: Fujitsu Limited
    Inventors: Hiroyoshi Ishikawa, Kazuo Nagatani, Nobukazu Fudaba
  • Patent number: 8712345
    Abstract: A distortion compensation device includes: a frequency-characteristic adding unit configured to add a frequency characteristic to an error signal to generate an added error signal, the error signal being a difference between an input signal input to an amplifier and an output signal output from the amplifier; a distortion-compensation-coefficient updating unit configured to update a distortion compensation coefficient for compensating for a distortion characteristic of the amplifier based on the added error signal; and a distortion compensation unit configured to perform distortion compensation on the input signal using the updated distortion compensation coefficient.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: April 29, 2014
    Assignee: Fujitsu Limited
    Inventors: Hiroyoshi Ishikawa, Kazuo Nagatani, Nobukazu Fudaba, Yuichi Utsunomiya
  • Patent number: 8655289
    Abstract: A distortion compensation device includes a distortion compensator that predistorts an input signal based on delay signals and distortion compensation coefficients corresponding to the respective delay signals obtained by applying different amounts of delay to the input signal, a calculator that calculates an error signal based on the predistorted input signal and an output signal from an amplifier that amplifies the predistorted input signal, a calculator that calculates prospective distortion compensation coefficients for updating the distortion compensation coefficients, based on the error signal, a saturation processor that performs saturation processing for bringing, when the prospective distortion compensation coefficients do not fall into a preset range, the prospective distortion compensation coefficients into the preset range, and a controller that controls the updating of the distortion compensation coefficients based on pieces of coefficient saturation information indicating whether the saturation
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: February 18, 2014
    Assignee: Fujitsu Limited
    Inventors: Nobukazu Fudaba, Hiroyoshi Ishikawa, Yuichi Utsunomiya, Kazuo Nagatani