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: 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
  • Publication number: 20230048332
    Abstract: A radio communication apparatus comprises a spreading unit and a transmitting unit. The spreading unit spreads an ACK/NACK signal or a CQI signal with a sequence defined by one of a plurality of cyclic shift values. The transmitting unit transmits the ACK/NACK signal or the CQI signal. In each symbol that forms the ACK/NACK signal or the CQI signal, the spreading unit uses one of first cyclic shift values, which form a portion of the plurality of the cyclic shift values and which are adjacent to each other, for the ACK/NACK signal, and uses one of second cyclic shift values, which are not within the portion of the plurality of the cyclic shift values, for the CQI signal. At least one cyclic shift value that is cyclically subsequent to the first cyclic shift values or the second cyclic shift values is not used for either the ACK/NACK signal or the CQI signal.
    Type: Application
    Filed: November 2, 2022
    Publication date: February 16, 2023
    Inventors: Sadaki FUTAGI, Seigo NAKAO, Daichi IMAMURA
  • Patent number: 11582630
    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: March 16, 2021
    Date of Patent: February 14, 2023
    Assignee: Sun Patent Trust
    Inventors: Yasuaki Yuda, Seigo Nakao, Ayako Horiuchi, Daichi Imamura, Masayuki Hoshino, Atsushi Sumasu
  • Patent number: 11569965
    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: April 5, 2021
    Date of Patent: January 31, 2023
    Assignee: Sun Patent Trust
    Inventors: Masayuki Hoshino, Akihiko Nishio, Daichi Imamura
  • Publication number: 20230024432
    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: October 3, 2022
    Publication date: January 26, 2023
    Inventors: Takashi IWAI, Akihiko NISHIO, Daichi IMAMURA, Yoshihiko OGAWA, Atsushi MATSUMOTO
  • Patent number: 11563540
    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: Grant
    Filed: April 14, 2021
    Date of Patent: January 24, 2023
    Assignee: Sun Patent Trust
    Inventors: Hui Tong, Ming Xu, Masayuki Hoshino, Daichi Imamura
  • Publication number: 20230013540
    Abstract: To suppress concentration of channel quality information requests and reports in a case of discontinuously transmitting reference signals at specific resources in a time domain, and thereby preventing degradation in throughput. A transmission apparatus transmits an instruction of CSI request distributed for each reception apparatus in a subframe concurrently with or earlier than a reference signal CSI-RS to each of reception apparatuses. Each of the reception apparatuses detects the CSI request from the transmission apparatus and calculates CSI from a channel estimation value of CSI-RS received thereafter. Then, the reception apparatus identifies CSI report subframe of the own apparatus from CSI report interval information of a given time interval notified in advance, the subframe in which the CSI request is detected and transmission timing of CSI-RS, and transmits a feedback signal including CSI report value by using PUSCH at the timing of the CSI report subframe.
    Type: Application
    Filed: September 28, 2022
    Publication date: January 19, 2023
    Inventors: Masayuki HOSHINO, Akihiko NISHIO, Seigo NAKAO, Daichi IMAMURA, Yasuaki YUDA
  • Patent number: 11558888
    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: May 28, 2021
    Date of Patent: January 17, 2023
    Assignee: Sun Patent Trust
    Inventors: Seigo Nakao, Daichi Imamura, Takahisa Aoyama
  • Patent number: 11552759
    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: Grant
    Filed: June 19, 2020
    Date of Patent: January 10, 2023
    Assignee: Sun Patent Trust
    Inventors: Hui Tong, Masayuki Hoshino, Ming Xu, Daichi Imamura
  • Publication number: 20230006874
    Abstract: Provided is a radio communication base station device which can suppress a use amount of an SRS communication resource. In this device, a correlation rule setting unit (102) sets a rule for correlating a preamble with an SRS transmission time interval so that the preamble transmission time band and the SRS transmission time band are in the same transmission time band. An SRS transmission band decision unit (103) decides a time interval of a transmission time band which can transmit the SRS according to the preamble transmission time interval inputted from a preamble transmission band decision unit (101) and the correlation rule setting unit (102).
    Type: Application
    Filed: September 7, 2022
    Publication date: January 5, 2023
    Inventors: Takashi IWAI, Daichi IMAMURA, Tomofumi TAKATA, Atsushi MATSUMOTO, Yoshihiko OGAWA, Sadaki FUTAGI
  • Publication number: 20220417921
    Abstract: Provided are a radio transmission device and a radio transmission method capable of improving downlink and uplink throughput even when performing dynamic symbol allocation. In the device and the method, BS and MS share a table correlating a basic TF as a combination of parameters such as TB size used for transmitting only user data, an allocation RB quantity, a modulation method, and an encoding ratio, with a derived TF having user data of different TB size by combining L1/L2 control information. Even when multiplexing L1/L2 control information, Index corresponding to the basic TF is reported from BS to MS.
    Type: Application
    Filed: August 30, 2022
    Publication date: December 29, 2022
    Inventors: Daichi IMAMURA, Hidetoshi SUZUKI, Akihiko NISHIO, Atsushi MATSUMOTO
  • Publication number: 20220416929
    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: Application
    Filed: September 2, 2022
    Publication date: December 29, 2022
    Inventors: Daichi Imamura, Takashi IWAI, Kazunori INOGAI, Sadaki FUTAGI, Atsushi MATSUMOTO
  • Patent number: 11540326
    Abstract: A radio performs random access by receiving control information and grouping a predetermined number of sequences that are generated from a plurality of base sequences into a plurality of groups by partitioning the predetermined number of sequences. At least one of the groups is associated with a first respective range of data amounts and a first respective range of reception qualities. Sequences generated from a common base sequence are arranged in an increasing order of respective cyclic shifts associated with the sequences. A sequence is randomly selected from a plurality of sequences contained in one group of the plurality of groups. A position at which the predetermined number of sequences are partitioned is determined based on the control information. A number of sequences contained in each of the plurality of groups varies in accordance with the control information.
    Type: Grant
    Filed: July 30, 2020
    Date of Patent: December 27, 2022
    Assignee: Optis Wireless Technology, LLC
    Inventors: Daichi Imamura, Sadaki Futagi, Atsushi Matsumoto, Takashi Iwai, Tomofumi Takata
  • Publication number: 20220399967
    Abstract: A data alignment method capable of preventing degradation in demodulation performance due to variation in signal qualities when a data signal to which a Turbo code is applied is transmitted simultaneously from a plurality of cells. The method divides signal components to be used for data alignment into resources common to all the cells and resources dependent on the cells and transmits encoded and rate-matched data with the first half thereof aligned to the resources common to all the cells and the second half thereof aligned to the resources dependent on the cells.
    Type: Application
    Filed: August 18, 2022
    Publication date: December 15, 2022
    Inventors: Masayuki HOSHINO, Seigo NAKAO, Daichi IMAMURA
  • Patent number: 11528065
    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: August 17, 2021
    Date of Patent: December 13, 2022
    Assignee: Apple Inc.
    Inventors: Hui Tong, Masayuki Hoshino, Ming Xu, Seigo Nakao, Daichi Imamura
  • Publication number: 20220394690
    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: August 16, 2022
    Publication date: December 8, 2022
    Inventors: Seigo Nakao, Akihiko Nishio, Daichi Imamura