Patents by Inventor Yoshihisa Kishiyama

Yoshihisa Kishiyama 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: 8917697
    Abstract: To provide a radio communication control method suitable for transmitting a downlink shared channel and a downlink control channel for the shared channel with different base frequency blocks in a communication system in which a plurality of base frequency blocks is combined and the system band is thereby broadened, in the radio communication control method, when different component carriers are assigned to a PDCCH and a PDCCH, to actualize a DCI configuration with a CFI value included in DCI notified on the PDCCH, the DCI is provided with an additional field on which CFI value bits are set. Further, to actualize another DCI configuration with a CFI value included in DCI notified on the PDCCH, part of the DCI field is masked with the CFI value.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: December 23, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Nobuhiko Miki, Yoshihisa Kishiyama
  • Publication number: 20140369223
    Abstract: The present invention is designed to detect an S-cell efficiently, in a short time, upon carrier aggregation in a HetNet. In a communication system where carrier aggregation is executed between a first carrier (CC #1) and a second carrier (CC #2), a macro base station apparatus (20A) generates a carrier detection signal that makes a mobile terminal apparatus (10) detect the second carrier (CC #2), such that carrier aggregation is executed with the first carrier (CC #1), and transmits the carrier detection signal to an RRH base station apparatus (20B) such that the carrier detection signal is transmitted from the RRH base station apparatus (20B) to the mobile terminal apparatus (10) in the second carrier (CC #2) in which the carrier detection signal can be allocated with a higher density than a reference signal of the first carrier (CC #1). The macro base station apparatus (20A) detects an S-cell based on the received quality of the carrier detection signal fed back from the mobile terminal apparatus (10).
    Type: Application
    Filed: January 30, 2013
    Publication date: December 18, 2014
    Inventors: Kazuaki Takeda, Yoshihisa Kishiyama, Sadayuki Abeta, Hiroyuki Ishii
  • Publication number: 20140369224
    Abstract: The present invention is designed to provide a wireless communication system, a base station apparatus, a user terminal, and a channel state information measurement method that can allow a user terminal to feed back channel quality information that is optimal for a transmission mode from a plurality of transmission points.
    Type: Application
    Filed: January 30, 2013
    Publication date: December 18, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshihisa Kishiyama
  • Patent number: 8902819
    Abstract: To provide a mobile terminal apparatus and radio communication method for enabling feedback control information to be efficiently transmitted on a physical uplink control channel, a mobile terminal apparatus of the invention receives downlink shared data channels parallel in a plurality of CCs, makes determinations on the downlink shared data channels about ACK/NACK/DTX, collectively codes determination results (states) of the plurality of CCs after reducing the number of states allowed to be notified individually, and performs signal processing on the coded data to be orthogonalized between users to transmit.
    Type: Grant
    Filed: June 21, 2011
    Date of Patent: December 2, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Yoshihisa Kishiyama, Nobuhiko Miki
  • Patent number: 8897281
    Abstract: Provided is a radio base station apparatus capable of transmitting a control signal efficiently even in radio communications using a system band that includes a plurality of component carriers. In the radio base station apparatus, control signals of transport blocks corresponding to the plural component carriers are coded jointly and the coded control signal is assigned to one or plural component carriers to be transmitted. A mobile terminal apparatus receives data from the radio base station apparatus, separates the control signal from the received data and decodes the separated control signal thereby to obtain control information of the transport blocks of the corresponding component carriers.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: November 25, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Nobuhiko Miki, Yoshihisa Kishiyama, Satoshi Nagata, Mamoru Sawahashi
  • Patent number: 8880089
    Abstract: In a mobile communication system including a first base station and a second base station, the first base station includes: a user information obtaining unit configured to obtain user information in the first base station, and the second base station includes: a user information obtaining unit configured to obtain user information in the second base station; a base station internal information collection unit configured to collect user information in the first and the second base stations; and a resource assignment determination unit configured to determine radio resources that can be used by the first base station and radio resources that can be used by the second base station based on the user information in the first and the second base stations.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: November 4, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Akihito Morimoto, Motohiro Tanno, Yoshihisa Kishiyama, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 8873437
    Abstract: A base station apparatus in a mobile communication system allowing for user equipment terminals having different numbers of receiving antennas is disclosed. The base station apparatus includes a mapping unit mapping a reference signal, a primary broadcasting signal, a synchronization signal, and an L1/L2 control signal onto a predetermined signal format; and a transmission unit transmitting the mapped signals, in which, within a sub-frame, the mapping unit maps the L1/L2 control signal and the primary broadcasting signal so as to be time-domain multiplexed, maps the primary broadcasting signal and the synchronization signal within a predetermined bandwidth in a middle of a system bandwidth, maps a reference signal included in a predetermined transmission stream within the predetermined bandwidth, but does not map a reference signal included in a transmission stream other than the predetermined transmission stream within the predetermined bandwidth.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: October 28, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Yoshihisa Kishiyama, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 8873501
    Abstract: A base station used in a mobile communication system employing a single carrier scheme for uplink transmission is disclosed. The base station includes a scheduler configured to allocate one or more uplink resource blocks to a user device according to uplink channel conditions of the user device; and a reporting unit configured to report scheduling information indicating the allocation result to the user device. An uplink control channel of the user device is mapped to a resource block in a transmission frame including multiple resource blocks according to a hopping pattern based on the scheduling information; and the uplink control channel is mapped to a resource block according to the same hopping pattern regardless of whether the uplink control channel is associated with a user data channel.
    Type: Grant
    Filed: June 13, 2007
    Date of Patent: October 28, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Teruo Kawamura, Yoshihisa Kishiyama, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20140314036
    Abstract: In a configuration in which a downlink control channel is enhanced, the present invention is designed to adequately allocate downlink control signals to radio resources for the enhanced control channel.
    Type: Application
    Filed: November 7, 2012
    Publication date: October 23, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Kazuaki Takeda, Yoshihisa Kishiyama, Satoshi Nagata
  • Patent number: 8867470
    Abstract: A mobile communication method according to the present invention comprises: a step A of individually notifying, by a radio base station eNB, a mobile station UE performing CA of correspondence relation between a DL carrier for transmitting an “UL grant” and an UL carrier to which a PUSCH resource is assigned by the “UL grant”, and a step B of transmitting, by the mobile station UE, an uplink data signal using the PUSCH resource through the UL carrier based on the above-described correspondence relation when the “UL grant” is received through the DL carrier.
    Type: Grant
    Filed: February 15, 2011
    Date of Patent: October 21, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Anil Umesh, Mikio Iwamura, Nobuhiko Miki, Yoshihisa Kishiyama
  • Publication number: 20140307576
    Abstract: To increase the number of CSI-RSs for interference measurement to improve interference measurement accuracy, a first reference signal for channel state measurement and a second reference signal for interference measurement are assigned to reference signal resources defined for transmission of the first reference signal, and a mobile terminal apparatus that supports both the first reference signal and the second reference signal is notified of pattern information to identify an assignment pattern of the first reference signal and the second reference signal. A second mobile terminal apparatus that supports the first reference signal and that does not support the second reference signal is notified of pattern information to identify an assignment pattern of the first reference signal, and of assignment information indicating that resources assigned the second reference signal are assigned a third reference signal of zero power for channel state measurement.
    Type: Application
    Filed: July 31, 2012
    Publication date: October 16, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshihisa Kishiyama, Anass Benjebbour, Wei Xi
  • Publication number: 20140307630
    Abstract: To enable a user terminal to determine a cell of a downlink signal also in a heterogeneous environment using the same cell identification information, and thereby enable reception accuracy to be maintained, a radio communication method of the invention is characterized in that a radio base station apparatus generates a reference signal sequence by using a pseudo random sequence including user specific information, and transmits the reference signal sequence to a user terminal, and that the user terminal performs signal processing using the reference signal sequence transmitted from the radio base station apparatus.
    Type: Application
    Filed: November 1, 2012
    Publication date: October 16, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshihisa Kishiyama, Kazuaki Takeda, Xiaoming She
  • Publication number: 20140307688
    Abstract: The present invention is designed to effectively apply carrier aggregation and CoMP transmission/reception in a system band that is formed with a plurality of fundamental frequency blocks. A radio communication system where carrier aggregation is applicable in the same frequency band, and, this radio communication system includes the first radio base station apparatus and a second radio base station apparatus that perform coordinated multiple point transmission to a user terminal using cells having the same frequency band, and the first radio base station apparatus and the second radio base station apparatus perform retransmission control for uplink signals from the user terminal on a shared basis, and perform mapping of downlink signals to radio resources separately.
    Type: Application
    Filed: November 9, 2012
    Publication date: October 16, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshihisa Kishiyama
  • Publication number: 20140307689
    Abstract: The present invention is designed to provide highly efficient local area radio access in a local area arranged in a wide area. A radio communication system has a wide area base station apparatus that covers a wide area, a local area base station apparatus that covers a local area arranged in the wide area, and a mobile terminal apparatus that communicates with the wide area base station apparatus by a radio communication scheme for the wide area, and that communicates with the local area base station apparatus by a radio communication scheme for the local area. The radio communication scheme for the local area is configured to utilize wide area control information that is used in the radio communication scheme for the wide area.
    Type: Application
    Filed: November 9, 2012
    Publication date: October 16, 2014
    Applicant: NTT DOCOMO, INC.
    Inventor: Yoshihisa Kishiyama
  • Publication number: 20140301340
    Abstract: The present invention is designed to measure interference with high accuracy, without changing the density of CSI-RSs, in a future system that does not reply on CRSs. A base station apparatus (20) allocates CSI-RS to CSI resources that are defined for CSI-RS transmission, changes arbitrary resources in the CSI-RS resources in resource block units or in resource block group units, and determines and reports to a mobile terminal apparatus (10) the resources to be muted, and the mobile terminal apparatus (10) is configured to measure interference using the muted resources.
    Type: Application
    Filed: November 7, 2012
    Publication date: October 9, 2014
    Inventors: Anass Benjebbour, Satoshi Nagata, Yoshihisa Kishiyama
  • Publication number: 20140301286
    Abstract: The present invention is designed to provide a radio base station apparatus, a mobile terminal apparatus, a radio communication system and a radio communication method which can cope with an increased number of users. A radio base station apparatus is provided with: a signal generating section that generates a first downlink control signal and a second downlink control signal for a mobile terminal apparatus; a first multiplexing section that multiplexes the first downlink control signal on a control region up to a predetermined number of symbols from the top of a subframe; a second multiplexing section that frequency-division-multiplexes the second downlink control signal on radio resources from the next symbol in the control region to the last symbol of the subframe; and a transmission section that transmits the first downlink control signal multiplexed on the control region and the second downlink control signal multiplexed on the radio resources.
    Type: Application
    Filed: February 17, 2012
    Publication date: October 9, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Tetsushi Abe, Yoshihisa Kishiyama, Satoshi Nagata, Nobuhiko Miki, Kazuaki Takeda
  • Publication number: 20140293947
    Abstract: To ensure stable operation of a user terminal even in the case where the user terminal is instructed to transmit uplink signals at different transmission timings with a plurality of component carriers, in a radio communication system provided with a radio base station apparatus that indicates transmission timings of uplink signals for each component carrier, and a user terminal that transmits an uplink signal at a transmission timing set based on transmission timing information indicated from the radio base station apparatus and the like, it is a feature that the radio base station apparatus indicates different transmission timing information in a plurality of component carriers, and that the user terminal avoids simultaneous transmission of uplink signals in the case of performing communications using a plurality of contiguous component carriers.
    Type: Application
    Filed: November 8, 2012
    Publication date: October 2, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Daisuke Nishikawa, Kazuaki Takeda, Satoshi Nagata, Yoshihisa Kishiyama, Tooru Uchino, Yuta Sagae
  • Patent number: 8843171
    Abstract: To provide a transmission power control method, base station apparatus and mobile station apparatus for enabling the transmission power in the mobile station apparatus having a plurality of antennas to be properly controlled, enabled is one of a common control mode for transmitting a common TPC command to perform transmission power control common to antennas (102a, 102b) to the mobile station apparatus (100) and an individual control mode for transmitting individual TPC commands to perform transmission power control individually on the antennas (102a, 102b) to the mobile station apparatus (100).
    Type: Grant
    Filed: September 18, 2009
    Date of Patent: September 23, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Daisuke Nishikawa, Yoshihisa Kishiyama, Mamoru Sawahashi
  • Publication number: 20140254539
    Abstract: The present invention is designed such that, in a heterogeneous environment where the same cell identification information is used, it is possible to identify from which cell a downlink signal has arrived, in a user terminal, and thereby maintain the accuracy of reception.
    Type: Application
    Filed: November 9, 2012
    Publication date: September 11, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshihisa Kishiyama
  • Patent number: 8817753
    Abstract: To provide a mobile terminal apparatus and radio communication method for enabling feedback control information to be efficiently transmitted on uplink channels, a radio communication method of the invention is characterized by having in a mobile terminal apparatus the steps of receiving a signal for each of a plurality of component carriers from a radio base station apparatus, generating feedback control information for each component carrier from the signal, mapping the feedback control information for each component carrier to suitable radio resources based on the number of component carriers, the presence or absence of uplink transmission data, and the number of bits of control information to transmit as feedback, and transmitting an uplink transmission signal mapped to the radio resources.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: August 26, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Teruo Kawamura, Yoshihisa Kishiyama, Mamoru Sawahashi