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).

  • Radio communication system and communication control method
    Patent number: 9634740
    Abstract: A radio communication system includes: a plurality of cells having different scrambling sequences, respectively, wherein at least two cells communicate with at least 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: Grant
    Filed: January 30, 2012
    Date of Patent: April 25, 2017
    Assignee: NEC Corporation
    Inventors: Le Liu, Yoshikazu Kakura, Naoto Ishii, Takamichi Inoue
  • RADIO COMMUNICATION SYSTEM AND METHOD
    Publication number: 20170078074
    Abstract: A radio communication system includes a network and a user terminal, wherein the network includes a plurality of radio stations and a controller which controls the plurality of radio stations, wherein at least two of the plurality of radio stations communicate with the user terminal, wherein the controller notifies the user terminal of information about resource for interference measurement, wherein the user terminal calculates and reports channel quality information based on the information.
    Type: Application
    Filed: November 29, 2016
    Publication date: March 16, 2017
    Inventors: Le LIU, Takamichi INOUE, Naoto ISHII, Yoshikazu KAKURA
  • Radio communication system and communication method
    Patent number: 9577740
    Abstract: A communication system includes a plurality of DeNBs (base stations) and a plurality of RNs (relay nodes), wherein each RN has a radio connection with a DeNB. Each DeNB acquires time resource configuration applied between another base station and a relay node connected with said another base station.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: February 21, 2017
    Assignee: NEC Corporation
    Inventors: Boonsarn Pitakdumrongkija, Yoshikazu Kakura, Naoto Ishii
  • Radio communication system and method
    Patent number: 9544793
    Abstract: A radio communication system includes a network and a user terminal, wherein the network includes a plurality of radio stations and a controller which controls the plurality of radio stations, wherein at least two of the plurality of radio stations communicate with the user terminal, wherein the controller notifies the user terminal of information about resource for interference measurement, wherein the user terminal calculates and reports channel quality information based on the information.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: January 10, 2017
    Assignee: NEC Corporation
    Inventors: Le Liu, Takamichi Inoue, Naoto Ishii, Yoshikazu Kakura
  • METHOD FOR MULTIPLEXING CONTROL SIGNALS AND REFERENCE SIGNALS IN MOBILE COMMUNICATIONS SYSTEM
    Publication number: 20160359594
    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: August 18, 2016
    Publication date: December 8, 2016
    Applicant: NEC CORPORATION
    Inventors: Takamichi INOUE, Yoshikazu KAKURA
  • Communication system, base station, mobile station, method for mobile station, and method for communication system
    Patent number: 9515762
    Abstract: A device and method in which a 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: December 6, 2016
    Assignee: NEC Corporation
    Inventors: Kengo Oketani, Yoshikazu Kakura
  • Radio communication system and communication method
    Patent number: 9496944
    Abstract: A communication system and method that allows a DeNB to identify a RN registered to another DeNB and to acquire necessary information for coordinating interference from RNs registered to the other DeNB are provided. The communication system includes a plurality of communication nodes which includes a plurality of base stations and a plurality of relay nodes, wherein each relay node has a radio connection with a base station, wherein each base station exchanges information indicating identity of a relay node with another base station.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: November 15, 2016
    Assignee: NEC Corporation
    Inventors: Boonsarn Pitakdumrongkija, Yoshikazu Kakura, Naoto Ishii
  • RADIO TERMINAL, RADIO STATION, RADIO COMMUNICATION SYSTEM, AND METHODS IMPLEMENTED THEREIN
    Publication number: 20160316386
    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: June 30, 2016
    Publication date: October 27, 2016
    Applicant: NEC Corporation
    Inventors: Hisashi FUTAKI, Hiroaki AMINAKA, Hiroto SUGAHARA, Yoshikazu KAKURA, Kazushi MURAOKA
  • RESOURCE ALLOCATION METHOD, IDENTIFICATION METHOD, BASE STATION, MOBILE STATION, AND PROGRAM
    Publication number: 20160286546
    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 3, 2016
    Publication date: September 29, 2016
    Applicant: NEC CORPORATION
    Inventors: Kenji KOYANAGI, Takamichi INOUE, Le LIU, Yoshikazu KAKURA
  • Method for multiplexing control signals and reference signals in mobile communications system
    Patent number: 9445414
    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: March 12, 2015
    Date of Patent: September 13, 2016
    Assignee: NEC CORPORATION
    Inventors: Takamichi Inoue, Yoshikazu Kakura
  • Radio terminal, radio station, radio communication system, and methods implemented therein
    Patent number: 9420482
    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: January 11, 2013
    Date of Patent: August 16, 2016
    Assignee: NEC Corporation
    Inventors: Hisashi Futaki, Hiroaki Aminaka, Hiroto Sugahara, Yoshikazu Kakura, Kazushi Muraoka
  • RESOURCE ALLOCATION METHOD, IDENTIFICATION METHOD, RADIO COMMUNICATION SYSTEM, BASE STATION, MOBILE STATION, AND PROGRAM
    Publication number: 20160234817
    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 19, 2016
    Publication date: August 11, 2016
    Applicant: NEC CORPORATION
    Inventors: Kenji KOYANAGI, Takamichi INOUE, Le LIU, Yoshikazu KAKURA
  • CONTROL APPARATUS, RADIO STATION, RADIO TERMINAL, RADIO SYSTEM, CONTROL METHOD, AND NON-TRANSITORY COMPUTER READABLE MEDIUM
    Publication number: 20160227487
    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: Application
    Filed: May 30, 2014
    Publication date: August 4, 2016
    Applicant: NEC Corporation
    Inventor: Yoshikazu KAKURA
  • Communication system, base station, mobile station, method for mobile station, and method for communication system
    Patent number: 9402246
    Abstract: A device and method in which a 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: June 11, 2013
    Date of Patent: July 26, 2016
    Assignee: NEC Corporation
    Inventors: Kengo Oketani, Yoshikazu Kakura
  • COMMUNICATION SYSTEM, BASE STATION, MOBILE STATION, METHOD FOR MOBILE STATION, AND METHOD FOR COMMUNICATION SYSTEM
    Publication number: 20160204890
    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: Application
    Filed: March 21, 2016
    Publication date: July 14, 2016
    Applicant: NEC Corporation
    Inventors: Kengo OKETANI, Yoshikazu KAKURA
  • PILOT SIGNAL TRANSMISSION METHOD AND RADIO COMMUNICATION APPARATUS
    Publication number: 20160204911
    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: Application
    Filed: March 21, 2016
    Publication date: July 14, 2016
    Applicant: NEC CORPORATION
    Inventors: Takamichi INOUE, Yoshikazu KAKURA
  • COMMUNICATION SYSTEM, BASE STATION, MOBILE STATION, METHOD FOR MOBILE STATION, AND METHOD FOR COMMUNICATION SYSTEM
    Publication number: 20160204918
    Abstract: A device and method in which a 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: March 21, 2016
    Publication date: July 14, 2016
    Applicant: NEC Corporation
    Inventors: Kengo OKETANI, Yoshikazu KAKURA
  • Pilot signal transmission method and radio communication apparatus
    Patent number: 9392492
    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: January 9, 2015
    Date of Patent: July 12, 2016
    Assignee: NEC CORPORATION
    Inventors: Takamichi Inoue, Yoshikazu Kakura
  • Resource allocation method, identification method, base station, mobile station, and program
    Patent number: 9386574
    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 19, 2009
    Date of Patent: July 5, 2016
    Assignee: NEC CORPORATION
    Inventors: Kenji Koyanagi, Takamichi Inoue, Le Liu, Yoshikazu Kakura
  • Resource allocation method, identification method, radio communication system, base station, mobile station, and program
    Patent number: 9350485
    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: June 19, 2009
    Date of Patent: May 24, 2016
    Assignee: NEC CORPORATION
    Inventors: Kenji Koyanagi, Takamichi Inoue, Le Liu, Yoshikazu Kakura