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: 11171819
    Abstract: A base station for transmitting a synchronization signal from N transmission antennas (N>=2) in orthogonal frequency division multiple access includes a signal sequence generation unit configured to generate a synchronization signal sequence to be used for the synchronization signal in a frequency domain; a subcarrier mapping unit configured to divide a transmission band of the synchronization signal into K frequency blocks (K>=2) and map the synchronization signal sequence into one or more subcarriers in the K frequency blocks; a precoding unit configured to generate N precoding vectors to be multiplied by the synchronization signal sequence in the frequency domain and multiply the synchronization signal sequence to be transmitted from an n-th antenna (1<=n<=N) by at least an n-th precoding vector; and a transmission unit configured to transmit the synchronization signal from the N transmission antennas.
    Type: Grant
    Filed: December 14, 2017
    Date of Patent: November 9, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Satoshi Nagata, Keisuke Saito, Mamoru Sawahashi
  • Patent number: 11128353
    Abstract: A radio base station making it possible to perform efficient scheduling of user terminals by reducing feedback information to be received from the user terminals is provided. A radio base station includes a position-related-information obtaining section configured to obtain position-related information indicating positional relationships among multiple user terminals. In addition, the radio base station includes a scheduler configured to determine user groups of the user terminals to be spatially multiplexed in the same time and frequency resources based on the position-related information obtained by the position-related-information obtaining section.
    Type: Grant
    Filed: April 25, 2018
    Date of Patent: September 21, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Anass Benjebbour, Yuuya Saitou, Yoshihisa Kishiyama
  • Publication number: 20210184787
    Abstract: To perform appropriate AMC control even if low latency is required. A transmission apparatus includes: a reception section that receives channel quality information communicated between the transmission apparatus and a reception apparatus; a control section that determines one or more first candidates for a value indicating a coding and modulation scheme based on the channel quality information, determines one or more second candidates for a value indicating the coding and modulation scheme based on a parameter related to service quality required for a service communicated between the transmission apparatus and the reception apparatus, and selects a value included in both of the first candidates and the second candidates; and a transmission section that transmits transmission data using the coding and modulation scheme corresponding to the selected value.
    Type: Application
    Filed: September 5, 2017
    Publication date: June 17, 2021
    Applicant: NTT DOCOMO, INC.
    Inventors: Masashi Iwabuchi, Anass Benjebbour, Yoshihisa Kishiyama
  • Patent number: 10998952
    Abstract: A user apparatus is disclosed herein that includes a receiver configured to receive a plurality of synchronization signals and a transmitter configured to transmit a sounding reference signal associated with a specific synchronization signal of the plurality of synchronization signals. The transmitter also maps the sounding reference signal to consecutive OFDM symbols in one slot.
    Type: Grant
    Filed: January 21, 2019
    Date of Patent: May 4, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Yuichi Kakishima
  • Publication number: 20210111767
    Abstract: A radio base station making it possible to perform efficient scheduling of user terminals by reducing feedback information to be received from the user terminals is provided. A radio base station includes a position-related-information obtaining section configured to obtain position-related information indicating positional relationships among multiple user terminals. In addition, the radio base station includes a scheduler configured to determine user groups of the user terminals to be spatially multiplexed in the same time and frequency resources based on the position-related information obtained by the position-related-information obtaining section.
    Type: Application
    Filed: April 25, 2018
    Publication date: April 15, 2021
    Applicant: NTT DOCOMO, INC.
    Inventors: Anass Benjebbour, Yuuya Saitou, Yoshihisa Kishiyama
  • Patent number: 10972167
    Abstract: A user apparatus communicating with a base station in a radio communication system including the base station and the user apparatus includes a first receiving unit to receive multiple first reference signals transmitted from the base station; a detection unit to detect a specific antenna port via which the plurality of first reference signals is received, or a specific directivity pattern, among a plurality of directivity patterns generated by a plurality of antenna ports, in which the plurality of first reference signals are received; a measuring unit to measure reception power of each of the first reference signals; and a transmission unit to group the reception power of each of the first reference signals into one of groups of the specific antenna port and the specific directivity pattern via which the first reference signals are received to transmit the groups of the reception power to the base station.
    Type: Grant
    Filed: August 30, 2019
    Date of Patent: April 6, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Daiki Takeda
  • Patent number: 10959237
    Abstract: The object is achieved by providing a base station apparatus for performing time and frequency scheduling in uplink packet access with: an interference amount measurement part configured to measure an uplink interference amount for each interference amount measurement unit which comprises a predetermined period and a predetermined number of frequency blocks; an interference amount determination part configured to determine whether the uplink interference amount satisfies a predetermined condition; and an overload indicator reporting part configured to report an overload indicator to a neighboring cell when the predetermined condition is satisfied.
    Type: Grant
    Filed: February 2, 2018
    Date of Patent: March 23, 2021
    Assignee: DENSO CORPORATION
    Inventors: Motohiro Tanno, Yoshihisa Kishiyama, Kenichi Higuchi, Mamoru Sawahashi, Toshifumi Sato
  • Patent number: 10924231
    Abstract: To provide a radio base station apparatus and radio communication method capable of performing radio communications using downlink reference signal structures suitable for antenna virtualization, a radio base station apparatus (200) has a plurality of transmission antennas, generates CRSs used in demodulation of at least downlink control information, CQI-RSs generated for each of the transmission antennas used in measurement of channel quality, and DM-RSs generated for each stream used in demodulation of downlink transmission data, and multiplexes the CRSs, CQI-RSs and DM-RSs into a same transmission time unit to transmit from each of the antennas.
    Type: Grant
    Filed: October 16, 2014
    Date of Patent: February 16, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Hidekazu Taoka, Mamoru Sawahashi
  • Patent number: 10820318
    Abstract: The present invention is designed so that adequate communication can be carried out even in future radio communication systems. A user terminal communicates using a transmission time interval (TTI), which has a predetermined TTI duration, and has a receiving section that receives a DL signal, a transmission section that transmits a UL signal, and a control section that controls at least one of transmission of a random access preamble, transmission of an SRS, reception of a broadcast channel and reception of a mobility reference signal, based on downlink control information that is included in the same TTI.
    Type: Grant
    Filed: February 27, 2017
    Date of Patent: October 27, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Kazuki Takeda
  • Patent number: 10805055
    Abstract: A system for supporting smooth mobility of a mobile terminal apparatus between a plurality of local areas that are arranged in a wide area is disclosed. The system includes 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 can communicate with the wide area base station apparatus and the local area base station apparatus, and is configured to scramble a data signal and a reference signal by a scrambling sequence that is common between a plurality of local areas in communication between the local area base station apparatus and the mobile terminal apparatus.
    Type: Grant
    Filed: June 27, 2013
    Date of Patent: October 13, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Kazuaki Takeda, Satoshi Nagata, Takehiro Nakamura, Hideaki Takahashi, Sadayuki Abeta, Hiroyuki Ishii
  • Publication number: 20200322925
    Abstract: The present invention is designed to allow adequate communication in a next generation communication system in which a plurality of numerologies are introduced. A control section that controls communication using at least one of a plurality of numerologies with different subcarrier spacings, and a receiving section that receives information related to numerology for use in communication are provided, and the plurality of numerologies with different subcarrier spacings are configured that one of the length of a transmission time interval (TTI) and the number of symbols per TTI is different.
    Type: Application
    Filed: March 22, 2017
    Publication date: October 8, 2020
    Applicant: NTT DOCOMO, INC.
    Inventors: Kazuki Takeda, Shimpei Yasukawa, Yoshihisa Kishiyama, Satoshi Nagata
  • Publication number: 20200322978
    Abstract: A terminal is disclosed that includes a receiver that receives higher layer signaling that indicates a periodic time period in which uplink transmission is not performed and a processor that monitors downlink control information for scheduling system information in the time period. In other aspects, a radio communication method and a base station are disclosed.
    Type: Application
    Filed: June 19, 2020
    Publication date: October 8, 2020
    Applicant: NTT DOCOMO, INC.
    Inventors: Kazuki Takeda, Yoshihisa Kishiyama, Hiroki Harada, Kazuaki Takeda, Satoshi Nagata
  • Patent number: 10797837
    Abstract: The present invention is designed to reduce the time it takes to form adequate beams, in communication using beamforming. According to one aspect of the present invention, a user terminal has a transmission section that, using temporally orthogonal radio resources, forms different transmitting beams and transmits reference signals respectively to a radio base station, and a control section that controls the forming of the transmitting beams so that at least one of the reference signals is received in a receiving beam which the radio base station forms in a given period set.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: October 6, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Kazuki Takeda, Hiroki Harada, Yoshihisa Kishiyama, Satoshi Nagata, Yousuke Sano
  • Patent number: 10791469
    Abstract: The present invention is designed to expand the coverage of reference signals in small cells that are arranged to overlap a macro cell, and, furthermore, reduce the interference between the small cells and improve the received quality of the reference signals in user terminals. The radio communication method of the present invention provides a radio communication method in a radio base station forming a small cell that is placed to overlap a macro cell, and includes the steps of generating a reference signal for measuring received quality, in a first transmission period in which beamforming is not executed, transmitting the reference signal in a narrower transmission bandwidth and with greater transmission power than in a second transmission period in which beamforming is executed, and allocating the reference signal to a band associated with information that is specific to each radio base station forming a small cell, and transmitting the reference signal.
    Type: Grant
    Filed: August 6, 2014
    Date of Patent: September 29, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Anass Benjebbour, Yoshihisa Kishiyama
  • Patent number: 10791470
    Abstract: The present invention is designed to shorten the time that a user terminal takes to detect the common control/reference signals while coverage of the common control/reference signals transmitted from a small base station is secured. As the radio communication method of the invention, a radio communication method is provided in which beam forming information for forming transmission beams directed from the small base station to the user terminal are generated based on position-related information of the user terminal acquired by communication between the macro base station and the user terminal using a coverage carrier and position-related information of the small base station, and the small base station precodes at least one of a common control signal and a reference signal that are common in a small cell based on the beam forming information and transmits the precoded signal from a plurality of transmitting antennas using a capacity carrier.
    Type: Grant
    Filed: October 13, 2017
    Date of Patent: September 29, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Anass Benjebbour, Yoshihisa Kishiyama
  • Publication number: 20200305122
    Abstract: The present invention is designed to realize appropriate communication in next generation communication systems. a control section that controls communication by using a radio frame that includes a plurality of transmission time intervals (TTIs), in which the downlink and the uplink can be switched, and a given TTI, which is for DL transmission and which is configured in a given cycle, and a receiving section that receives a synchronization signal and a broadcast signal in the given TTI are provided.
    Type: Application
    Filed: March 24, 2017
    Publication date: September 24, 2020
    Applicant: NTT DOCOMO, INC.
    Inventors: Hiroki Harada, Kazuki Takeda, Yoshihisa Kishiyama, Satoshi Nagata
  • Patent number: 10779280
    Abstract: A small base station executes radio communication using multiple antennas. There are set multiple antenna groups that each include all or a portion of the antennas and multiple antenna group patterns that each include at least one of the antenna groups. The small base station transmits reference signals with sequences that differ from one another between antenna groups that are included in the same antenna group pattern. A user apparatus receives the reference signals. Based on a reception result of the reference signals, a use antenna group pattern and at least one use antenna group that are to be used for transmission of a radio signal from the small base station are determined.
    Type: Grant
    Filed: June 2, 2015
    Date of Patent: September 15, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Anass Benjebbour, Yoshihisa Kishiyama
  • Patent number: 10721692
    Abstract: A radio communication method is provided in which a local area base station apparatus, arranged in a wide area where a first carrier frequency is used and forming a local area that is narrower than the wide area, transmits a downlink signal, using a second carrier frequency, which belongs to a different frequency band from the first carrier frequency and which has a wider bandwidth than the first carrier frequency, the local area base station apparatus transmits a detection signal that is used to detect the local area base station apparatus in the mobile terminal apparatus, and the local area base station apparatus transmits the downlink signal for the mobile terminal apparatus with transmission power that is determined based on the path loss of the detection signal received in the mobile terminal apparatus.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: July 21, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Anass Benjebbour, Kazuaki Takeda
  • Patent number: 10721615
    Abstract: This invention aims to achieve appropriate communication even when a radio frame configuration which may involve short-time feedback is used. In an aspect of this invention, provided is a user terminal in a system which performs communication based on a TTI (Transmission Time Interval) length, the equipment including a transmission and reception unit which transmits and/or receives capability information concerning a supportable delay, and a control unit which performs control to receive a certain downlink radio resource and/or transmit a certain uplink radio resource at a time interval equal to or greater than the delay.
    Type: Grant
    Filed: February 27, 2017
    Date of Patent: July 21, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Kazuki Takeda
  • Patent number: 10652048
    Abstract: A user equipment is disclosed that includes a receiver configured to receive candidates of phase rotation in a horizontal direction and candidates of phase rotation in a vertical direction for precoding. The user equipment also has a processor configured to report feedback information including a phase rotation in the horizontal direction and a phase rotation in the vertical direction to a radio base station based upon the candidates of the phase rotation in a horizontal direction and the candidates of phase rotation in a vertical direction. Additionally, the candidates of phase rotation in the horizontal direction or the candidates of phase rotation in the vertical direction are a part of predetermined candidates, the part being selected from the predetermined candidates according to a predetermined method.
    Type: Grant
    Filed: November 14, 2018
    Date of Patent: May 12, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Yuichi Kakishima, Satoshi Nagata, Yoshihisa Kishiyama