Patents by Inventor Yoshiaki Ofuji

Yoshiaki Ofuji 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: 7974177
    Abstract: User equipment that is capable of transmitting at least an uplink control channel to a base station apparatus using a single carrier method and to which persistent scheduling is applied, the user equipment includes a unit providing data arrival acknowledgement information, a unit providing channel quality information, a control channel generation unit generating an uplink control channel including at least one of the data arrival acknowledgement information or the channel quality information, and a transmission unit transmitting the uplink control channel using a predetermined dedicated bandwidth, in which the uplink control channel includes at least one unit block including a sequence in which a same factor reported using an upper-layer signaling is multiplied to each chip of an orthogonal code sequence for the user equipment.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: July 5, 2011
    Assignee: NTT DoCoMo, Inc.
    Inventors: Yoshiaki Ofuji, Anil Umesh, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20110149896
    Abstract: One aspect of the present invention relates to a base station wherein either resource blocks resulting from division of a system bandwidth into blocks of consecutive frequency subcarriers or distributed type resource blocks consisting of frequency subcarriers discretely distributed within the system bandwidth and resulting from segmentation of the resource blocks into multiple resource blocks are assigned to mobile stations, the base station including: a scheduling unit configured to assign either the resource blocks or the distributed type resource blocks to the mobile stations at a predefined assignment cycle based on respective downlink reception channel states transmitted from the mobile stations.
    Type: Application
    Filed: March 4, 2011
    Publication date: June 23, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20110134892
    Abstract: A radio base station of the present invention is provided with an index setting unit configured to set an index to a radio resource in a frequency domain, a resource allocation class determining unit is configured to determine a resource allocation class of a radio communication terminal from among resource allocation classes which are classified according to radio resource allocation patterns fixedly allocated at a fixed time interval T0, based on user information of the radio communication terminal, and a resource allocation unit configured to allocate a vacant radio resource within the fixed time interval T0 to the radio communication terminal in order starting with a radio resource having an index value predetermined for the resource allocation class.
    Type: Application
    Filed: December 3, 2010
    Publication date: June 9, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Masashige Shirakabe, Takahiro Asai, Akihito Hanaki, Yoshiaki Ofuji
  • Publication number: 20110064044
    Abstract: A disclosed transmission apparatus comprises a switching portion that switches radio access methods; a frequency domain signal generation portion that allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion is performed in accordance with the switched radio accessed method, so as to generate a signal in a frequency domain; and a transmission signal generation portion that performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.
    Type: Application
    Filed: November 17, 2010
    Publication date: March 17, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Hiroyuki Atarashi, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20110038434
    Abstract: An apparatus for generating sets of radio parameters includes a first deriving unit deriving a set of radio parameters for specifying a symbol including an effective symbol part with the same period as the effective symbol part specified by another set of radio parameters and a guard interval part with a different period from the guard interval part specified by the other set of radio parameters. The apparatus further includes a second deriving unit deriving a set of radio parameters so that an occupancy proportion of the guard interval part in a single symbol specified by another set of radio parameters is equal to an occupancy proportion of the guard interval part in a single symbol specified by the other set of radio parameters.
    Type: Application
    Filed: October 27, 2010
    Publication date: February 17, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Mamoru Sawahashi, Kenichi Higuchi, Hiroyuki Atarashi, Motohiro Tanno, Yoshihisa Kishiyama, Yoshiaki Ofuji
  • Publication number: 20110026417
    Abstract: A base station for use in a mobile communication system includes: a measurement unit configured to measure one or more pieces of statistical data in the number of users in a cell, a user distribution state or a traffic amount; and a deriving unit configured to derive a value of a radio parameter corresponding to currently measured statistical data from predetermined correspondence relationship between the statistical data and the radio parameter. A value of the radio parameter set as office data in the base station is automatically updated to a value derived by the deriving unit.
    Type: Application
    Filed: October 31, 2008
    Publication date: February 3, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Yoshiaki Ofuji, Mamoru Sawahashi, Kenichi Higuchi
  • Patent number: 7848447
    Abstract: An apparatus for generating sets of radio parameters includes a first deriving unit deriving a set of radio parameters for specifying a symbol including an effective symbol part with the same period as the effective symbol part specified by another set of radio parameters and a guard interval part with a different period from the guard interval part specified by the other set of radio parameters. The apparatus further includes a second deriving unit deriving a set of radio parameters so that an occupancy proportion of the guard interval part in a single symbol specified by another set of radio parameters is equal to an occupancy proportion of the guard interval part in a single symbol specified by the other set of radio parameters.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: December 7, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mamoru Sawahashi, Kenichi Higuchi, Hiroyuki Atarashi, Motohiro Tanno, Yoshihisa Kishiyama, Yoshiaki Ofuji
  • Publication number: 20100232374
    Abstract: One aspect of the present invention relates to a base station wherein either resource blocks resulting from division of a system bandwidth into blocks of consecutive frequency subcarriers or distributed type resource blocks consisting of frequency subcarriers discretely distributed within the system bandwidth and resulting from segmentation of the resource blocks into multiple resource blocks are assigned to mobile stations, the base station including: a scheduling unit configured to assign either the resource blocks or the distributed type resource blocks to the mobile stations at a predefined assignment cycle based on respective downlink reception channel states transmitted from the mobile stations.
    Type: Application
    Filed: August 17, 2007
    Publication date: September 16, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20100177715
    Abstract: A disclosed transmission device includes a frequency scheduling unit configured to allocate a resource block divided from a system bandwidth into blocks of consecutive frequency subcarriers or distributed-type resource blocks including discretely-distributed frequency subcarriers in a system bandwidth and divided from the resource block, assign locations and identification numbers of the distributed-type resource blocks divided by a predetermined division number with respect to each resource block, and determine the distributed-type resource blocks to be allocated to a user based on the assigned locations of the distributed-type resource blocks; a mapping unit configured to allocate transmission data to either the resource block or distributed-type resource blocks in accordance with the allocation; and a control information generating unit configured to generate control information with respect to a mobile station to which either the resource block or the distributed-type resource blocks are allocated based o
    Type: Application
    Filed: August 17, 2007
    Publication date: July 15, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20100157913
    Abstract: A transmission device is disclosed that includes a frequency scheduling unit configured to allocate resource blocks as a unit to each user, the resource blocks being blocks of consecutive frequency subcarriers divided from a system bandwidth, constitute a first group including consecutive plural resource blocks, constitute plural second groups, each including one or more resource blocks of the plural resource blocks constituting each first group, and allocate the resource blocks of either the first group or one or more the second groups; a mapping unit configured to allocate transmission data to the resource blocks in accordance with the allocation; and a control information generating unit configured to generate control information with respect to a mobile station to which either the first group or one or more the second groups are allocated.
    Type: Application
    Filed: August 13, 2007
    Publication date: June 24, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 7668150
    Abstract: An apparatus for packet-priority control for controlling a priority for packets input includes packet-priority setting means for setting hierarchically the priority for the packet input based on predetermined elements, and to adjust, taking into account other elements according to which the priority for the packet varies over time, the set priority, and wireless-resource allocating means for determining a packet for which a wireless resource is to be allocated in accordance with the adjusted priority.
    Type: Grant
    Filed: September 2, 2004
    Date of Patent: February 23, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Yoshiaki Ofuji, Sadayuki Abeta, Mamoru Sawahashi
  • Publication number: 20100040036
    Abstract: A disclosed base station is used in a radio communication system where sounding reference signals from user terminals are multiplexed using distributed FDMA in which distributed frequency blocks each including frequency subcarriers discretely distributed in a system bandwidth are allocated to the user terminals, and the system bandwidth is repeatedly halved into frequency band segments according to a binary-tree structure.
    Type: Application
    Filed: December 27, 2007
    Publication date: February 18, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20100027483
    Abstract: A mobile communication system in which a finite number of reference signal sequences used for uplink channel estimation or the like are reused among multiple cells includes a determining unit configured to determine a frequency band used by user terminals to which a reference signal sequence with a predetermined sequence length is assigned in each of the cells within an interference area, wherein the frequency band is determined to be different from frequency bands used in the other cells.
    Type: Application
    Filed: June 14, 2007
    Publication date: February 4, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20100014473
    Abstract: A CQI report method disclosed that includes a step in which the user equipment reports CQI information of top N resource block(s) having channel quality higher than the rest of the resource block(s) and a resource block number(s) of the top N resource block(s) to the base station at CQI report timings designated by the base station; and a step in which, when, for example, a resource block(s) whose CQI information has already been reported in any of the latest K report timings is included in the top N resource block(s), the user equipment excludes the resource block(s) and reports the CQI information of a resource block having the next highest channel quality indicator and the resource block number of the resource block to the base station.
    Type: Application
    Filed: October 1, 2007
    Publication date: January 21, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20100002655
    Abstract: User equipment that is capable of transmitting at least an uplink control channel to a base station apparatus using a single carrier method and to which persistent scheduling is applied, the user equipment includes a unit providing data arrival acknowledgement information, a unit providing channel quality information, a control channel generation unit generating an uplink control channel including at least one of the data arrival acknowledgement information or the channel quality information, and a transmission unit transmitting the uplink control channel using a predetermined dedicated bandwidth, in which the uplink control channel includes at least one unit block including a sequence in which a same factor reported using an upper-layer signaling is multiplied to each chip of an orthogonal code sequence for the user equipment.
    Type: Application
    Filed: December 26, 2007
    Publication date: January 7, 2010
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Anil Umesh, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20090303950
    Abstract: A base station apparatus is disclosed that includes a unit generating a low-layer control channel including at least resource allocation information and transmission system information of a data channel to be transmitted to a user equipment, a unit separately performing channel coding on each low-layer control channel of the plural sets of the user equipment, a unit transmitting the data channel and the low-layer control channel to the user equipment, and a determination unit configured to determine a multiplexing system of a downlink radio resource based on at least one of mobility of the user equipment and a traffic type. In the base station apparatus, high-layer control information indicating that the multiplexing system of the downlink radio resource is either a localized FDM system or a distributed FDM system is transmitted via the data channel.
    Type: Application
    Filed: September 28, 2007
    Publication date: December 10, 2009
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20090280841
    Abstract: A disclosed paging method includes a random access channel generating step of, when a group including an own station is being paged based on a paging indicator channel (PICH) transmitted from a base station apparatus, generating a random access channel (RACH) including information indicating a response to the paging indicator channel (PICH) by a mobile station apparatus; a transmitting step of transmitting the random access channel (RACH) by the mobile station apparatus; a random access channel detecting step of detecting the random access channel (RACH) as the response to the paging indicator channel (PICH) by the base station apparatus; a paging information generation determining step of determining whether paging information is to be generated based on a detection result of the random access channel (RACH); and a paging information generating step of generating paging information based on the determination result.
    Type: Application
    Filed: June 14, 2007
    Publication date: November 12, 2009
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Yoshihisa Kishiyama, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20090275342
    Abstract: A channel quality information reporting method includes a setting step, wherein the number N of blocks for which the mobile station reports channel quality information among the M blocks is set in accordance with an amount of traffic; a reporting step, wherein the base station reports the number N of blocks to the mobile station; a receiving step, wherein the mobile station receives the number N of blocks from the base station; a selecting step, wherein the mobile station selects N pieces of channel quality information from M pieces of channel quality information corresponding to the M blocks; an averaging step, wherein the mobile station averages pieces of channel quality information excluding the selected N pieces of the channel quality information; and a reporting step, wherein the mobile station reports the N pieces of channel quality information and the averaged channel quality information to the base station.
    Type: Application
    Filed: June 15, 2007
    Publication date: November 5, 2009
    Applicant: NTT DOCOMO, INC.
    Inventors: Mikio Iwamura, Yoshiaki Ofuji, Minami Ishii
  • Publication number: 20090225666
    Abstract: A base station includes a transmission method determining portion that determines whether to allow a mobile station to transmit a propagation path measuring signal by one of a multi-carrier method and a single carrier method; and a transmission method sending portion that sends information indicating the determined transmission method with the mobile station. A mobile station includes a data mapping portion that maps a signal sequence of a propagation path state measuring signal in accordance with transmission information that a base station sends in order to indicate the propagation path state measuring signal is transmitted by either one of a single carrier method and a multi-carrier method.
    Type: Application
    Filed: March 19, 2007
    Publication date: September 10, 2009
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshiaki Ofuji, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20090207803
    Abstract: A disclosed base station in a mobile communications system which uses a single-carrier technique for uplink includes a classifying unit which classifies, for each of multiple user apparatuses according to a path loss between the respective user apparatus and the base station, the multiple user apparatuses into two or more groups; and a scheduler which plans allocating of uplink resources to the user apparatuses. Uplink signals of each user apparatus that have multiple frequency components lined up in equal frequency intervals are multiplexed using a distributed frequency division multiplexing technique such that they are made mutually orthogonal on a frequency axis, the scheduler plans the resource allocating such that the user apparatuses belonging to different groups utilize different group bands or different time slots, and the group bands are specified by dividing a system band into groups.
    Type: Application
    Filed: June 13, 2007
    Publication date: August 20, 2009
    Applicant: NTT DoCoMo, Inc.
    Inventors: Teruo Kawamura, Yoshiaki Ofuji, Yoshihisa Kishiyama, Kenichi Higuchi, Mamoru Sawahashi, Seizo Onoe