Patents by Inventor Daichi Imamura

Daichi Imamura 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).

  • Publication number: 20210226758
    Abstract: The present disclosure provides a terminal device that allows constraints on user allocation to be prevented and spread codes to be allocated in a scheduler when non-adaptive HARQ is employed using a PHICH. A codeword generator generates code words by encoding data, a layer mapping unit places each CW in one or a plurality of layers, a DMRS generator generates a reference signal for each layer in which a CW is placed by using any resource among a plurality of resources defined by a mutually orthogonal plurality of OCCs, and an ACK/NACK demodulator receives a response signal indicating a retransmission request. When a response signal requesting retransmission of only a CW placed in a plurality of layers is received, the DMRS generator uses each resource having the same OCC among the plurality of resources for the reference signals generated in the corresponding layers.
    Type: Application
    Filed: April 5, 2021
    Publication date: July 22, 2021
    Inventors: Masayuki Hoshino, Akihiko Nishio, Daichi Imamura
  • Publication number: 20210211969
    Abstract: An integrated circuit includes circuitry, which, in operation, controls transmitting downlink data to a terminal apparatus; receiving a plurality of transport blocks which are transmitted in a same time period using a same frequency band in a spatial multiplexing scheme, wherein a same acknowledgement information (ACK/NACK) relating to an error detection result of the downlink data is scrambled with different scrambling schemes respectively for the plurality of transport blocks and the respectively scrambled ACK/NACK is multiplexed with data on respective ones of the plurality of transport blocks, and channel quality information (CQI) of a downlink channel is multiplexed with the data on only one transport block of the plurality of transport blocks by the terminal apparatus; and extracting the ACK/NACK and the CQI from the received plurality of transport blocks.
    Type: Application
    Filed: March 22, 2021
    Publication date: July 8, 2021
    Inventors: Yoshihiko OGAWA, Seigo NAKAO, Akihiko NISHIO, Masayuki HOSHINO, Daichi IMAMURA, Atsushi SUMASU
  • Patent number: 11057920
    Abstract: A base station is disclosed, including an information size adjusting section configured to adjust a size of control information based on a first basic information size of control information mapped on a user equipment (UE) specific search space in a first component carrier. The base station also includes a transmitter configured to transmit the control information mapped on the UE specific search space. A first determination method for determining the first basic information size is different from a second determination method for determining a second basic information size of control information mapped on a common search space in the first component carrier. The first determination method for determining the first basic information size is different from a third determination method for determining a third basic information size of control information mapped on a search space in a second component carrier that is different from the first component carrier.
    Type: Grant
    Filed: November 27, 2019
    Date of Patent: July 6, 2021
    Assignee: Sun Patent Trust
    Inventors: Seigo Nakao, Daichi Imamura, Takahisa Aoyama
  • Publication number: 20210204159
    Abstract: To measure the channel quality of the own cell accurately in a condition where there is no interference from a neighbor cell. A wireless communication terminal according to the invention is a wireless communication terminal to be connected to a base station for transmitting and receiving data to/from the base station, the wireless communication terminal including: a receiver that receives a signal which includes control information provided for measuring a channel quality of own cell from the base station; an extractor that extracts the control information from the signal received by the receiver; a measurement section that measures, on the basis of the control information, the channel quality of the own cell in a domain where a neighbor cell does not transmit a signal; and a transmitter that transmits a measurement result of the channel quality of the own cell measured by the measurement section, to the base station.
    Type: Application
    Filed: March 16, 2021
    Publication date: July 1, 2021
    Inventors: Yasuaki YUDA, Seigo NAKAO, Ayako HORIUCHI, Daichi IMAMURA, Masayuki HOSHINO, Atsushi SUMASU
  • Patent number: 11051294
    Abstract: Provided are a radio terminal device, a radio base station device, and a channel signal forming method which can prevent quality degradation of the downlink resource allocation information by reducing the frequency of the zero information addition process to the downlink resource allocation information when executing communication using an uplink unit band and multiple downlink unit bands correlated to the uplink unit band. A base station includes: a PDCCH generation unit which includes the uplink allocation information relating to the uplink unit band only in some of the channel signals formed for each of the downlink unit bands; and a padding unit which adds zero information to the downlink allocation information only in the selected some channel signals having the bandwidth of the corresponding downlink unit band smaller than that of the uplink unit band until the downlink allocation information size becomes equal to the uplink allocation information size.
    Type: Grant
    Filed: February 27, 2020
    Date of Patent: June 29, 2021
    Assignee: Sun Patent Trust
    Inventors: Seigo Nakao, Akihiko Nishio, Daichi Imamura, Takahisa Aoyama
  • Patent number: 11051345
    Abstract: A user terminal apparatus includes a receiver to receive a control information value belonging to a set of multiple control information values. Each control information value in the set of multiple control information values is associated with a subset of random access sequences from multiple subsets of random access sequences. Different ones of the multiple subsets of random access sequences are associated with different amounts of data. A data processor selects a random access sequence from one of the subset of random access sequences based on the control information value. A transmitter transmits the selected random access sequence.
    Type: Grant
    Filed: January 29, 2020
    Date of Patent: June 29, 2021
    Assignee: Optis Wireless Technology, LLC
    Inventors: Daichi Imamura, Sadaki Futagi, Atsushi Matsumoto, Takashi Iwai, Tomofumi Takata
  • Patent number: 11051313
    Abstract: It is possible to provide a radio communication terminal device and a radio transmission method which can improve reception performance of a CQI and a reference signal. A phase table storage unit stores a phase table which correlates the amount of cyclic shift to complex coefficients {w1, w2} to be multiplied on the reference signal. A complex coefficient multiplication unit reads out a complex coefficient corresponding to the amount of cyclic shift indicated by resource allocation information, from the phase table storage unit and multiplies the read-out complex coefficient on the reference signal so as to change the phase relationship between the reference signals in a slot.
    Type: Grant
    Filed: March 31, 2020
    Date of Patent: June 29, 2021
    Assignee: Sun Patent Trust
    Inventors: Tomofumi Takata, Daichi Imamura, Seigo Nakao, Sadaki Futagi, Takashi Iwai, Yoshihiko Ogawa
  • Publication number: 20210194537
    Abstract: A radio communication apparatus includes spreading circuitry that spreads a response signal using a first set of orthogonal sequences to produce a spread response signal. Each orthogonal sequence in the first set has a first length. The spreading circuitry also spreads a reference signal using a second set of orthogonal sequences to produce a spread reference signal. Each orthogonal sequence in the second set has a second length that is shorter than the first length. A radio transmitter transmits the spread response signal and the spread reference signal.
    Type: Application
    Filed: March 10, 2021
    Publication date: June 24, 2021
    Inventors: Seigo Nakao, Daichi Imamura, Akihiko Nishio, Masayuki Hoshino
  • Publication number: 20210184725
    Abstract: A wireless communication terminal apparatus wherein CoMP communication can normally be performed without increasing the overhead of an upstream line control channel. In this apparatus, a spreading unit (214) primarily spreads a response signal by use of a ZAC sequence established by a control unit (209). A spreading unit (217) secondarily spreads the response signal, to which CP has been added, by use of a block-wise spread code sequence established by the control unit (209). The control unit (209) controls, in accordance with sequence numbers and a hopping pattern established therein, the circular shift amount of the ZAC sequence to be used for the primary spread in the spreading unit (214) and the block-wise spread code sequence to be used for the secondary spread in the spreading unit (217). The hopping pattern established in the control unit (209) is a hopping pattern common to a plurality of base stations that CoMP-receive the response signal.
    Type: Application
    Filed: February 19, 2021
    Publication date: June 17, 2021
    Inventors: Seigo NAKAO, Hidetoshi SUZUKI, Daichi IMAMURA
  • Publication number: 20210184818
    Abstract: A wireless communication base station apparatus which is able to prevent deterioration in the throughput of LTE terminals even when LTE terminals and LTE+ terminals coexist. In this apparatus, based on the mapping pattern of the reference signals used only in LTE+ terminals, a setting unit sets, in each subframe, the resource block groups where the reference signals used only by the LTE+ terminals are mapped. For symbols mapped to the antennas, an mapping unit maps, to all the resource blocks within one frame, cell specific reference signals used for both LTE terminals and LTE+ terminals. For the symbols mapped to the antennas, the mapping unit maps, to the plurality of resource blocks, of which part of the resource block groups is comprised, in the same subframe within one frame, the cell specific reference signals used only for LTE+ terminals, based on the setting results inputted from the setting unit.
    Type: Application
    Filed: February 5, 2021
    Publication date: June 17, 2021
    Inventors: Akihiko Nishio, Seigo Nakao, Daichi Imamura
  • Patent number: 11038633
    Abstract: Provided is a radio communication device which can make Acknowledgement (ACK) reception quality and Negative Acknowledgement (NACK) reception quality to be equal to each other. The device includes: a scrambling unit (214) which multiplies a response signal after modulated, by a scrambling code “1” or “e?j(?/2)” so as to rotate a constellation for each of response signals on a cyclic shift axis; a spread unit (215) which performs a primary spread of the response signal by using a Zero Auto Correlation (ZAC) sequence set by a control unit (209); and a spread unit (218) which performs a secondary spread of the response signal after subjected to the primary spread, by using a block-wise spread code sequence set by the control unit (209).
    Type: Grant
    Filed: April 21, 2020
    Date of Patent: June 15, 2021
    Assignee: Panasonic Corporation
    Inventors: Seigo Nakao, Daichi Imamura
  • Patent number: 11039483
    Abstract: A sequence allocating method and apparatus wherein in a system where a plurality of different Zadoff-Chu sequences or GCL sequences are allocated to a single cell, the arithmetic amount and circuit scale of a correlating circuit at a receiving end can be reduced. In ST201, a counter (a) and a number (p) of current sequence allocations are initialized, and in ST202, it is determined whether the number (p) of current sequence allocations is coincident with a number (K) of allocations to one cell. In ST203, it is determined whether the number (K) of allocations to the one cell is odd or even. If K is even, in ST204-ST206, sequence numbers (r=a and r=N?a), which are not currently allocated, are combined and then allocated. If K is odd, in ST207-ST212, for sequences that cannot be paired, one of sequence numbers (r=a and r=N?a), which are not currently allocated, is allocated.
    Type: Grant
    Filed: May 7, 2020
    Date of Patent: June 15, 2021
    Assignee: Panasonic Corporation
    Inventors: Daichi Imamura, Takashi Iwai, Kazunori Inogai, Sadaki Futagi, Atsushi Matsumoto
  • Publication number: 20210176750
    Abstract: The purpose of the present invention is to inhibit an increase in the amount of A/N resources, without changing the timing at which the error detection result of an SCell is notified when UL-DL configurations to be configured for each of the unit bands are different, from the timing at which the error detection result is notified when just a single unit band is configured. A control unit transmits, using a first unit band, a response signal including error detection results about data received with both the first unit band and a second unit band. In a first composition pattern set for the first unit band, an uplink communication subframe is set to be the same timing as at least an uplink communication subframe of a second composition pattern set for the second unit band.
    Type: Application
    Filed: February 23, 2021
    Publication date: June 10, 2021
    Inventors: Toru Oizumi, Daichi Imamura, Akihiko Nishio, Hidetoshi Suzuki
  • Publication number: 20210168732
    Abstract: A radio communication apparatus is provided, which includes a receiver and a controller. The receiver, in operation, receives a first power headroom (PHR), which is obtained by subtracting a transmit power for a data channel from a maximum transmit power at a mobile station and which is transmitted from the mobile station, and receives a second PHR, which is obtained by subtracting the transmit power for the data channel and a transmit power for a control channel from the maximum transmit power at the mobile station and which is transmitted from the mobile station. The controller, in operation, selectively sets a simultaneous transmission of the data channel and the control channel in different frequency bands to be performed by the mobile station. When the data channel and the control channel are simultaneously transmitted in different frequency bands from the mobile station, the second PHR is obtained and transmitted from the mobile station.
    Type: Application
    Filed: February 8, 2021
    Publication date: June 3, 2021
    Inventors: Takashi Iwai, Akihiko Nishio, Daichi Imamura, Yoshihiko Ogawa, Atsushi Matsumoto
  • Publication number: 20210160833
    Abstract: Disclosed is a base station in which the frequency usage efficiency can be improved when the communication bandwidths are asymmetric in the uplink line and the downlink line. A base station can communicate by using a plurality of downlink unit bands and a smaller number of uplink unit bands. A control unit allocates uplink resource allocation information and downlink resource allocation information to a PDCCH which is arranged in each of the plurality of downlink unit bands, and allocates a response signal to the uplink line data to a PHICH which is arranged in the same number of downlink unit bands from the plurality of downlink unit bands as there are uplink unit bands. A transmit RF unit transmits the resource allocation information or the response signal.
    Type: Application
    Filed: February 4, 2021
    Publication date: May 27, 2021
    Inventors: Seigo Nakao, Akihiko Nishio, Daichi Imamura
  • Patent number: 11019578
    Abstract: Provided is a terminal with which it is possible, in a heterogeneous cell network, to transmit a Periodic-Sounding Reference Signal (P-SRS) at a transmission bandwidth and power density necessary for carrying out both a process of selection of a transceiving participating base station and a process of frequency scheduling of a Physical Uplink Shared Channel (PUSCH). A terminal (300) comprises a receiving unit (301) which receives control information which includes information which denotes a P-SRS transmission parameter, and a transmission unit (303) which, using a transmission parameter which is included in the received control information, transmits a first P-SRS provided with a first bandwidth and a first power density at a first period, and transmits a second P-SRS provided with a second bandwidth which is narrower than the first bandwidth and second power density which is higher than the first power density at a second period.
    Type: Grant
    Filed: February 13, 2019
    Date of Patent: May 25, 2021
    Assignee: SUN PATENT TRUST
    Inventors: Kazuki Takeda, Akihiko Nishio, Daichi Imamura
  • Patent number: 11012212
    Abstract: A method and a system of setting up a reference signal in a radio communication system are disclosed. The radio communication system includes a serving cell and a neighboring cell, and a mobile terminal of the serving cell uses the same temporal frequency resource to receive a serving resource block from the serving cell and an interference resource block from the neighboring cell. The method includes setting up a user-specific reference signal in the interference resource block and puncturing at the same temporal frequency position as the temporal frequency position at which the user-specific reference signal is set up on the interference resource block of the serving resource block to prevent any signal from being transmitted at the punctured temporal frequency position. When the method and the system are used and the interference power between cells is measured, it is possible to effectively reduce feedback overhead in a coordinated beamforming.
    Type: Grant
    Filed: December 16, 2019
    Date of Patent: May 18, 2021
    Assignee: Sun Patent Trust
    Inventors: Hui Tong, Ming Xu, Masayuki Hoshino, Daichi Imamura
  • Patent number: 10999040
    Abstract: The present disclosure provides a terminal device that allows constraints on user allocation to be prevented and spread codes to be allocated in a scheduler when non-adaptive HARQ is employed using a PHICH. A codeword generator generates code words by encoding data, a layer mapping unit places each CW in one or a plurality of layers, a DMRS generator generates a reference signal for each layer in which a CW is placed by using any resource among a plurality of resources defined by a mutually orthogonal plurality of OCCs, and an ACK/NACK demodulator receives a response signal indicating a retransmission request. When a response signal requesting retransmission of only a CW placed in a plurality of layers is received, the DMRS generator uses each resource having the same OCC among the plurality of resources for the reference signals generated in the corresponding layers.
    Type: Grant
    Filed: January 9, 2020
    Date of Patent: May 4, 2021
    Assignee: Sun Patent Trust
    Inventors: Masayuki Hoshino, Akihiko Nishio, Daichi Imamura
  • Patent number: 10993223
    Abstract: Method of scrambling signals, transmission point device, and user equipment using the method are provided. The method includes: sending an ID table to a user equipment through higher layer signaling, the ID table being a subset of the whole ID space and containing available IDs for the user equipment; notifying the user equipment an ID in the ID table to be used through physical layer signaling or UE specific higher layer signaling; generating a random seed based on the notified ID; initializing a scrambling sequence by the random seed; and scrambling the signals with the initialized scrambling sequence. The method of the disclosure, by combining physical layer signaling and higher layer signaling, may notify the used group ID and the blind detection space to a UE, wherein the blind detection for the UE is enabled and the signaling overhead is reduced.
    Type: Grant
    Filed: June 25, 2020
    Date of Patent: April 27, 2021
    Assignee: Sun Patent Trust
    Inventors: Zhi Zhang, Ming Xu, Masayuki Hoshino, Daichi Imamura, Akihiko Nishio
  • Patent number: 10986524
    Abstract: To measure the channel quality of the own cell accurately in a condition where there is no interference from a neighbor cell. A wireless communication terminal according to the invention is a wireless communication terminal to be connected to a base station for transmitting and receiving data to/from the base station, the wireless communication terminal including: a receiver that receives a signal which includes control information provided for measuring a channel quality of own cell from the base station; an extractor that extracts the control information from the signal received by the receiver; a measurement section that measures, on the basis of the control information, the channel quality of the own cell in a domain where a neighbor cell does not transmit a signal; and a transmitter that transmits a measurement result of the channel quality of the own cell measured by the measurement section, to the base station.
    Type: Grant
    Filed: December 20, 2019
    Date of Patent: April 20, 2021
    Assignee: Sun Patent Trust
    Inventors: Yasuaki Yuda, Seigo Nakao, Ayako Horiuchi, Daichi Imamura, Masayuki Hoshino, Atsushi Sumasu