Patents by Inventor Yoshikazu Kakura

Yoshikazu Kakura 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: 10091779
    Abstract: To solve a problem that although the increase of the number of frequency blocks by allocating discontinuous subcarriers (RBs) as in OFDM enables an increase in multi-diversity effect and an improvement in throughput, the number of RB allocation patterns increases with the increase of the number of frequency blocks, resulting in an increase in the amount of information relating to the allocated RBs, the resource block allocation unit is determined when resource blocks discontinuous on the frequency axis are allocated to a terminal, and the number of bits of scheduling information indicating the allocated resource blocks by using Tree Based is set to the number of bits corresponding to the determined allocation unit.
    Type: Grant
    Filed: April 26, 2017
    Date of Patent: October 2, 2018
    Assignee: NEC CORPORATION
    Inventors: Kenji Koyanagi, Takamichi Inoue, Le Liu, Yoshikazu Kakura
  • Publication number: 20180249357
    Abstract: In one embodiment, a radio terminal (2) is used in a radio communication system (100) and communicates with a radio station (1). The radio terminal (2) includes a measurement unit (20). The measurement unit (20) operates to perform, using a terminal measurement procedure for executing a first terminal measurement corresponding to radio access technology applied to the radio communication system (100), a second terminal measurement of a shared frequency shared by a plurality of radio systems including the radio communication system (100). This embodiment therefore contributes to simplification of a measurement function which should be supported by the radio terminal when the radio communication system uses a shared frequency (e.g., TVWS) shared by the plurality of radio systems.
    Type: Application
    Filed: April 27, 2018
    Publication date: August 30, 2018
    Applicant: NEC Corporation (c/o Hibiki IP Law Firm)
    Inventors: Hisashi FUTAKI, Hiroaki AMINAKA, Hiroto SUGAHARA, Yoshikazu KAKURA, Kazushi MURAOKA
  • Patent number: 10034248
    Abstract: Provided is a control apparatus that can improve throughput of a cell edge user while preventing the throughput of the cell edge user. A control apparatus (10) according to the present invention is disposed in a radio system including communication areas formed by a plurality of cells using the same frequency band. The control apparatus (10) includes a pattern determining unit (110) for defining a cell group including one or more cells formed by radio stations (1) to (6) and determining a time pattern of transmission power to be set for each of a plurality of the cell groups and a communication unit (120) for notifying the radio stations (1) to (6) that form the cells included in the cell group of the time patterns of the transmission power and timing signals indicating switching timings of the transmission power in the radio stations (1) to (6).
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: July 24, 2018
    Assignee: NEC Corporation
    Inventor: Yoshikazu Kakura
  • Patent number: 10028158
    Abstract: A radio terminal (2) is used in a radio communication system (100) and communicates with a radio station (1). The radio terminal (2) includes a measurement unit (20). The measurement unit (20) operates to perform, using a terminal measurement procedure for executing a first terminal measurement corresponding to radio access technology applied to the radio communication system (100), a second terminal measurement of a shared frequency shared by a plurality of radio systems including the radio communication system (100).
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: July 17, 2018
    Assignee: NEC Corporation
    Inventors: Hisashi Futaki, Hiroaki Aminaka, Hiroto Sugahara, Yoshikazu Kakura, Kazushi Muraoka
  • Publication number: 20170366315
    Abstract: A device and method is which plurality of Zadoff-Chu sequences is allocated to a frame, a value of a parameter in the Zadoff-Chu sequence is different among the plurality of Zadoff-Chu sequences, and the Zadoff-Chu sequence allocated to the frame is different among a plurality of cells.
    Type: Application
    Filed: September 6, 2017
    Publication date: December 21, 2017
    Applicant: NEC Corporation
    Inventors: Kengo OKETANI, Yoshikazu KAKURA
  • Publication number: 20170332266
    Abstract: In one embodiment, a radio terminal (2) is used in a radio communication system (100) and communicates with a radio station (1). The radio terminal (2) includes a measurement unit (20). The measurement unit (20) operates to perform, using a terminal measurement procedure for executing a first terminal measurement corresponding to radio access technology applied to the radio communication system (100), a second terminal measurement of a shared frequency shared by a plurality of radio systems including the radio communication system (100). This embodiment therefore contributes to simplification of a measurement function which should be supported by the radio terminal when the radio communication system uses a shared frequency (e.g., TVWS) shared by the plurality of radio systems.
    Type: Application
    Filed: August 4, 2017
    Publication date: November 16, 2017
    Applicant: NEC Corporation
    Inventors: Hisashi FUTAKI, Hiroaki AMINAKA, Hiroto SUGAHARA, Yoshikazu KAKURA, Kazushi MURAOKA
  • Publication number: 20170318588
    Abstract: A base station includes a transmitter configured to transmit a downlink control information to a user equipment, the downlink control information being generated based on one of (1) a first uplink allocation information indicating a first frequency block corresponding to a first plurality of subcarriers which are contiguous in frequency and (2) a second uplink allocation information indicating a second frequency block corresponding to a second plurality of subcarriers which are contiguous in frequency and a third frequency block corresponding to a third plurality of subcarriers which are contiguous in frequency, the second frequency block and the third frequency block being separated in frequency.
    Type: Application
    Filed: July 17, 2017
    Publication date: November 2, 2017
    Applicant: NEC CORPORATION
    Inventors: Takamichi INOUE, Kenji KOYANAGI, Le LIU, Yoshikazu KAKURA
  • Patent number: 9787378
    Abstract: A communication system, a terminal apparatus, a base station apparatus, and a method for sharing a codebook are provided that make it possible to improve system capacity by using precoding according to a cell environment. In a communication system in which beam directivity control is performed by precoding using a codebook that is common between a base station (10) and a terminal (20), the base station (10) notifies the terminal (20) information for codebook determination k including cell (11)-specific information on the base station, and the base station (10) and the terminal (20) generate the common codebook based on the information for codebook determination.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: October 10, 2017
    Assignee: NEC Corporation
    Inventors: Shinichi Tajima, Naoto Ishii, Yoshikazu Kakura
  • Patent number: 9787421
    Abstract: A device and method in which plurality of Zadoff-Chu sequences is allocated to a frame, a value of a parameter in the Zadoff-Chu sequence is different among the plurality of Zadoff-Chu sequences, and the Zadoff-Chu sequence allocated to the frame is different among a plurality of cells.
    Type: Grant
    Filed: March 21, 2016
    Date of Patent: October 10, 2017
    Assignee: NEC Corporation
    Inventors: Kengo Oketani, Yoshikazu Kakura
  • Publication number: 20170289996
    Abstract: Provided is a technique capable of reporting resource block allocation information with no waste when an allocated resource block is reported, because in the current LTE downlink, the waste of the amount of resource allocation information increases in some cases since a restriction is imposed such that 37-bit fixed scheduling information is transmitted. A resource block group consisting of at least one or more resource blocks continuous on the frequency axis is allocated to a terminal, and the number of controlling signals for reporting allocation information indicating the allocated resource blocks is determined.
    Type: Application
    Filed: June 15, 2017
    Publication date: October 5, 2017
    Applicant: NEC CORPORATION
    Inventors: Kenji KOYANAGI, Takamichi INOUE, Le LIU, Yoshikazu KAKURA
  • Patent number: 9781618
    Abstract: A radio terminal (2) is provided that can be used in a radio communication system (100) and can communicate with a radio station (1). The radio terminal (2) includes a measurement unit (20). The measurement unit (20) operates to perform, using a terminal measurement procedure for executing a first terminal measurement corresponding to radio access technology applied to the radio communication system (100), a second terminal measurement of a shared frequency shared by a plurality of radio systems including the radio communication system (100).
    Type: Grant
    Filed: June 30, 2016
    Date of Patent: October 3, 2017
    Assignee: NEC Corporation
    Inventors: Hisashi Futaki, Hiroaki Aminaka, Hiroto Sugahara, Yoshikazu Kakura, Kazushi Muraoka
  • Publication number: 20170272215
    Abstract: A reference signal multiplexing method for multiple mobile stations includes: grouping together control signals for the multiple mobile stations; and multiplexing reference signals corresponding to the control signals by CDM over the same bandwidth as that of grouped control signals.
    Type: Application
    Filed: June 2, 2017
    Publication date: September 21, 2017
    Applicant: NEC CORPORATION
    Inventors: Takamichi INOUE, Yoshikazu KAKURA
  • Publication number: 20170251490
    Abstract: A radio communication system includes: a plurality of cells having different scrambling sequences, respectively, wherein at least two cells communicate with at lease two user terminals connected to different serving cells; and a controller which controls the plurality of cells and provides a single scrambling sequence to said at least two cells and said at least two user terminals for control signal transmission and reception.
    Type: Application
    Filed: March 15, 2017
    Publication date: August 31, 2017
    Inventors: Le LIU, Yoshikazu Kakura, Naoto Ishii, Takamichi Inoue
  • Patent number: 9743410
    Abstract: A base station includes a transmitter configured to transmit a downlink control information to a user equipment, the downlink control information being generated based on one of (1) a first uplink allocation information indicating a first frequency block corresponding to a first plurality of subcarriers which are contiguous in frequency and (2) a second uplink allocation information indicating a second frequency block corresponding to a second plurality of subcarriers which are contiguous in frequency and a third frequency block corresponding to a third plurality of subcarriers which are contiguous in frequency, the second frequency block and the third frequency block being separated in frequency.
    Type: Grant
    Filed: September 30, 2016
    Date of Patent: August 22, 2017
    Assignee: NEC CORPORATION
    Inventors: Takamichi Inoue, Kenji Koyanagi, Le Liu, Yoshikazu Kakura
  • Patent number: 9735938
    Abstract: In a radio communication system, transmission of CAZAC sequences as the pilot signal sequences by using code division multiplexing as at least one of user multiplexing schemes, is done by dividing a system band as a frequency band usable in the system into frequency blocks B1 and B2 having bandwidths W1 and W2, generating the pilot signals of the frequency blocks B1 and B2 with a single carrier, using the pilot signal sequences having sequence lengths L1 and L2 corresponding to frequency blocks B1 and B2 respectively; and, transmitting the generated pilot signals as the pilot signals corresponding individual users, with multicarriers using an arbitrary number of frequency blocks among the plural frequency blocks.
    Type: Grant
    Filed: March 21, 2016
    Date of Patent: August 15, 2017
    Assignee: NEC CORPORATION
    Inventors: Takamichi Inoue, Yoshikazu Kakura
  • Publication number: 20170230151
    Abstract: A radio communication system according to the present invention includes a base station (10) configured to start or stop a data transmission process according to presence/absence of a terminal with which the base station (10) communicates, a base station (20) whose communication area includes a place where a terminal (40) is present, the terminal (40) being affected by interference when the data transmission process is performed in the base station (10), and a control device (30) configured to control a start timing of the data transmission process in the base station (10) and transmit information about the start timing of the data transmission process in the base station (10) to the base station (20).
    Type: Application
    Filed: April 28, 2015
    Publication date: August 10, 2017
    Applicant: NEC Corporation
    Inventor: Yoshikazu KAKURA
  • Publication number: 20170230949
    Abstract: To solve a problem that although the increase of the number of frequency blocks by allocating discontinuous subcarriers (RBs) as in OFDM enables an increase in multi-diversity effect and an improvement in throughput, the number of RB allocation patterns increases with the increase of the number of frequency blocks, resulting in an increase in the amount of information relating to the allocated RBs, the resource block allocation unit is determined when resource blocks discontinuous on the frequency axis are allocated to a terminal, and the number of bits of scheduling information indicating the allocated resource blocks by using Tree Based is set to the number of bits corresponding to the determined allocation unit.
    Type: Application
    Filed: April 26, 2017
    Publication date: August 10, 2017
    Applicant: NEC CORPORATION
    Inventors: Kenji KOYANAGI, Takamichi INOUE, Le LIU, Yoshikazu KAKURA
  • Patent number: 9713130
    Abstract: Provided is a technique capable of reporting resource block allocation information with no waste when an allocated resource block is reported, because in the current LTE downlink, the waste of the amount of resource allocation information increases in some cases since a restriction is imposed such that 37-bit fixed scheduling information is transmitted. A resource block group consisting of at least one or more resource blocks continuous on the frequency axis is allocated to a terminal, and the number of controlling signals for reporting allocation information indicating the allocated resource blocks is determined.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: July 18, 2017
    Assignee: NEC CORPORATION
    Inventors: Kenji Koyanagi, Takamichi Inoue, Le Liu, Yoshikazu Kakura
  • Patent number: 9692570
    Abstract: A reference signal multiplexing method for multiple mobile stations includes: grouping together control signals for the multiple mobile stations; and multiplexing reference signals corresponding to the control signals by CDM over the same bandwidth as that of grouped control signals.
    Type: Grant
    Filed: August 18, 2016
    Date of Patent: June 27, 2017
    Assignee: NEC CORPORATION
    Inventors: Takamichi Inoue, Yoshikazu Kakura
  • Patent number: 9668256
    Abstract: To solve a problem that although the increase of the number of frequency blocks by allocating discontinuous subcarriers (RBs) as in OFDM enables an increase in multi-diversity effect and an improvement in throughput, the number of RB allocation patterns increases with the increase of the number of frequency blocks, resulting in an increase in the amount of information relating to the allocated RBs, the resource block allocation unit is determined when resource blocks discontinuous on the frequency axis are allocated to a terminal, and the number of bits of scheduling information indicating the allocated resource blocks by using Tree Based is set to the number of bits corresponding to the determined allocation unit.
    Type: Grant
    Filed: April 19, 2016
    Date of Patent: May 30, 2017
    Assignee: NEC CORPORATION
    Inventors: Kenji Koyanagi, Takamichi Inoue, Le Liu, Yoshikazu Kakura