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).

  • Patent number: 11757501
    Abstract: The present disclosure provides a method of generating codebook in a wireless communication system with multiple antenna arrays, as well as a wireless communication system, base station and terminal using the codebook for communication. The method comprises steps of: providing a basic codebook which contains multiple pre-coding matrices; and assigning phase offsets to certain pre-coding matrices in the basic codebook to form a codebook with phase offset. The feedback overhead from a client to a base station side is reduced and a good precision of feedback for multi-antenna array is kept by applying the method of generating codebook and using the generated codebook in the wireless communication system, base station and terminal.
    Type: Grant
    Filed: November 8, 2022
    Date of Patent: September 12, 2023
    Assignee: Apple Inc.
    Inventors: Hui Tong, Masayuki Hoshino, Ming Xu, Seigo Nakao, Daichi Imamura
  • Patent number: 11751143
    Abstract: Disclosed is a wireless communication device that can suppress an increase in power consumption of a terminal while preventing the degradation of SINR measurement precision resulting from TPC errors in a base station. A terminal controls the transmission power of a second signal by adding an offset to the transmission power of a first signal; an offset-setting unit sets an offset correction value in response to a transmission time gap between a third signal transmitted the previous time and the second signal transmitted this time; and a transmission power control unit controls the transmission power of the second signal using the correction value.
    Type: Grant
    Filed: April 27, 2022
    Date of Patent: September 5, 2023
    Assignee: Sun Patent Trust
    Inventors: Takashi Iwai, Daichi Imamura, Akihiko Nishio, Yoshihiko Ogawa, Shinsuke Takaoka
  • Patent number: 11751181
    Abstract: A scheduling apparatus and a scheduling method, wherein the amount of signaling for frequency resource allocation information can be reduced while maintaining system throughput performance. In a base station apparatus, a scheduling section allocates frequency resources to frequency allocation target terminals based on set frequency allocation units, and a frequency allocation parameter setting section adjusts the set frequency allocation units set in the scheduling section based on cluster numbers. Due to this, in each cluster number, frequency resources can be allocated based on the most suitable frequency allocation units with respect to the signaling bit number. As a result, the amount of signaling for frequency resource allocation information can be reduced. Further, system throughput can be maintained by making the cluster number, which is a parameter having little effect on system throughput, a setting parameter for frequency allocation units.
    Type: Grant
    Filed: December 16, 2021
    Date of Patent: September 5, 2023
    Assignee: Sun Patent Trust
    Inventors: Takashi Iwai, Sadaki Futagi, Daichi Imamura, Akihiko Nishio, Seigo Nakao, Yoshihiko Ogawa
  • Patent number: 11742974
    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: September 2, 2022
    Date of Patent: August 29, 2023
    Assignee: Panasonic Holdings Corporation
    Inventors: Daichi Imamura, Takashi Iwai, Kazunori Inogai, Sadaki Futagi, Atsushi Matsumoto
  • Publication number: 20230269711
    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: April 25, 2023
    Publication date: August 24, 2023
    Inventors: Toru Oizumi, Daichi Imamura, Akihiko Nishio, Hidetoshi Suzuki
  • Patent number: 11728953
    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: Grant
    Filed: June 23, 2022
    Date of Patent: August 15, 2023
    Assignee: Sun Patent Trust
    Inventors: Akihiko Nishio, Seigo Nakao, Daichi Imamura
  • Patent number: 11711791
    Abstract: It is an object to provide a sequence allocating method that, while maintaining the number of Zadoff-Chu sequences to compose a sequence group, is configured to make it possible to reduce correlations between different sequential groups. This method comprises the steps of setting a standard sequence with a standard sequence length and a standard sequence number in a step, setting a threshold value in accordance with an RB number in a step, setting a sequence length corresponding to RB number in a step, judging whether ¦r/N?rb/Nb¦=Xth(m) is satisfied in a step, including a plurality of Zadoff-Chu sequences with a sequence number and a sequence length in a sequence group in a step if the judgment is positive, and allocating the sequence group to the same cell in a step.
    Type: Grant
    Filed: January 7, 2022
    Date of Patent: July 25, 2023
    Assignee: PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA
    Inventors: Takashi Iwai, Daichi Imamura, Tomofumi Takata, Yoshihiko Ogawa
  • Patent number: 11700076
    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: May 10, 2022
    Date of Patent: July 11, 2023
    Assignee: Panasonic Holdings Corporation
    Inventors: Seigo Nakao, Daichi Imamura
  • Patent number: 11700098
    Abstract: Disclosed are a wireless transmitter and a reference signal transmission method that improve channel estimation accuracy. In a terminal, which transmits a reference signal using n (n is a non-negative integer 2 or greater) band blocks (which correspond to clusters here), which are disposed with spaces therebetween in a frequency direction, a reference signal controller switches the reference signal formation method of a reference signal generator between a first formation method and a second formation method based on the number (n) of band blocks. In addition, a threshold value setting unit adjusts a switching threshold value based on the frequency spacing between band blocks. Thus, the reference signal formation method can be selected with good accuracy and, as a result, channel estimation accuracy is further improved.
    Type: Grant
    Filed: June 16, 2022
    Date of Patent: July 11, 2023
    Assignee: Sun Patent Trust
    Inventors: Takashi Iwai, Sadaki Futagi, Tomohumi Takata, Daichi Imamura, Yoshihiko Ogawa
  • Patent number: 11700611
    Abstract: Provided are a communication device and an SRS transmission method capable of reducing the possibility of a difference in recognition between the presence or absence of an SRS transmission between a base station and a terminal or of an SRS resource so as to prevent degradation of system throughput. At a terminal (200), a reception processing unit (203) detects control information indicating whether or not to request transmission of a sounding reference signal (SRS), whereupon a transmission signal forming unit (207) transmits an A-SRS by way of control by a transmission control unit (206) on the basis of control information. The transmission control unit (206) determines whether or not to execute SRS transmission on the basis of an “SRS Transmission Execution Rule” and the reception status of trigger information.
    Type: Grant
    Filed: March 4, 2022
    Date of Patent: July 11, 2023
    Assignee: Sun Patent Trust
    Inventors: Akihiko Nishio, Daichi Imamura
  • Patent number: 11689986
    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: Grant
    Filed: March 22, 2021
    Date of Patent: June 27, 2023
    Assignee: Sun Patent Trust
    Inventors: Yoshihiko Ogawa, Seigo Nakao, Akihiko Nishio, Masayuki Hoshino, Daichi Imamura, Atsushi Sumasu
  • Publication number: 20230189043
    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: January 9, 2023
    Publication date: June 15, 2023
    Inventors: Yasuaki YUDA, Seigo NAKAO, Ayako HORIUCHI, Daichi IMAMURA, Masayuki HOSHINO, Atsushi SUMASU
  • Patent number: 11671947
    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: March 23, 2021
    Date of Patent: June 6, 2023
    Assignee: SUN PATENT TRUST
    Inventors: Zhi Zhang, Ming Xu, Masayuki Hoshino, Daichi Imamura, Akihiko Nishio
  • Patent number: 11671950
    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: Grant
    Filed: February 23, 2021
    Date of Patent: June 6, 2023
    Assignee: Sun Patent Trust
    Inventors: Toru Oizumi, Daichi Imamura, Akihiko Nishio, Hidetoshi Suzuki
  • Publication number: 20230142975
    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: January 3, 2023
    Publication date: May 11, 2023
    Inventors: Masayuki Hoshino, Akihiko Nishio, Daichi Imamura
  • Publication number: 20230117146
    Abstract: A communication apparatus includes a receiver and a transmitter. The receiver, in operation, receives from a neighboring cell a reference signal mapped to at least one first resource element. No signal is received from a serving cell on the at least one first resource element. The transmitter, in operation, transmits to a base station measurement information obtained based on the reference signal.
    Type: Application
    Filed: December 19, 2022
    Publication date: April 20, 2023
    Inventors: Hui TONG, Ming XU, Masayuki HOSHINO, Daichi IMAMURA
  • Publication number: 20230120645
    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: Application
    Filed: December 14, 2022
    Publication date: April 20, 2023
    Inventors: Seigo Nakao, Daichi Imamura, Takahisa Aoyama
  • Publication number: 20230096976
    Abstract: A Method of scrambling reference signals, device and user equipment using the method are provided. In the method, a plurality of layers of reference signals assigned on predetermined radio resource of a plurality of layers of resource blocks with the same time and frequency resources are scrambled, the method comprising: an orthogonalizing step of multiplying each layer of reference signal selectively by one of a plurality of orthogonal cover codes (OCCs) with the same length wherein the OCC multiplied to a first layer of reference signal can be configured as different from those multiplied to other layers of reference signals; and a scrambling step of multiplying all of symbols obtained from the OCC multiplied to each of the other layers of reference signals by a symbol-common scrambling sequence wherein the symbol-common scrambling sequences can be different from each other for reference signals multiplied by the same OCC.
    Type: Application
    Filed: December 7, 2022
    Publication date: March 30, 2023
    Inventors: Hui TONG, Masayuki HOSHINO, Ming XU, Daichi IMAMURA
  • Publication number: 20230084236
    Abstract: The present disclosure provides a method of generating codebook in a wireless communication system with multiple antenna arrays, as well as a wireless communication system, base station and terminal using the codebook for communication. The method comprises steps of: providing a basic codebook which contains multiple pre-coding matrices; and assigning phase offsets to certain pre-coding matrices in the basic codebook to form a codebook with phase offset. The feedback overhead from a client to a base station side is reduced and a good precision of feedback for multi-antenna array is kept by applying the method of generating codebook and using the generated codebook in the wireless communication system, base station and terminal.
    Type: Application
    Filed: November 8, 2022
    Publication date: March 16, 2023
    Applicant: Apple Inc.
    Inventors: Hui Tong, Masayuki Hoshino, Ming Xu, Seigo Nakao, Daichi Imamura
  • Publication number: 20230085207
    Abstract: A radio communication device capable of randomizing both inter-cell interference and intra-cell interference. In this device, a spreading section primarily spreads a response signal in a ZAC sequence set by a control unit. A spreading section secondarily spreads the primarily spread response signal in a block-wise spreading code sequence set by the control unit. The control unit controls the cyclic shift amount of the ZAC sequence used for the primary spreading in the spreading section and the block-wise spreading code sequence used for the secondary spreading in the spreading section according to a set hopping pattern. The hopping pattern set by the control unit is made up of two hierarchies. An LB-based hopping pattern different for each cell is defined in the first hierarchy in order to randomize the inter-cell interference. A hopping pattern different for each mobile station is defined in the second hierarchy to randomize the intra-cell interference.
    Type: Application
    Filed: November 7, 2022
    Publication date: March 16, 2023
    Inventors: Seigo NAKAO, Daichi IMAMURA, Katsuhiko HIRAMATSU