Patents by Inventor Seigo Nakao

Seigo Nakao 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: 20210006312
    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: September 23, 2020
    Publication date: January 7, 2021
    Inventors: Hui Tong, Masayuki Hoshino, Ming Xu, Seigo Nakao, Daichi Imamura
  • Publication number: 20200396016
    Abstract: A terminal apparatus includes circuitry and a transmitter. The circuitry, in operation, generates a reference signal using a cyclic shift value and an orthogonal sequence, which are associated with each other. The orthogonal sequence is one of two orthogonal sequences corresponding to a first orthogonal sequence [1, 1] and a second orthogonal sequence [1, ?1]. The cyclic shift value is one of 12 cyclic shift values ranging from 0 to 11. The transmitter, in operation, transmits the reference signal multiplexed with a data signal. Two of the cyclic shift values having a difference of 6 are respectively associated with the two orthogonal sequences.
    Type: Application
    Filed: August 27, 2020
    Publication date: December 17, 2020
    Inventors: Yoshihiko Ogawa, Akihiko Nishio, Takashi Iwai, Seigo Nakao, Daichi Imamura, Atsushi Sumasu
  • Publication number: 20200389913
    Abstract: A base station able to maintain backward compatibility with an LTE mobile station while minimizing the amount of increase in uplink scheduling information reception and demodulation/decoding processing in independent uplink/downlink cell data transmission. A wireless communication system includes a cell #1, a cell #2, and an LTE-A mobile station, and supports independent uplink/downlink cell data transmission. The base station of the cell #2 arranges a PDCCH+, which includes uplink scheduling information from the LTE-A mobile station to the base station of the cell #2, in a downlink data region in the downlink connection of the base station of the cell #1.
    Type: Application
    Filed: August 24, 2020
    Publication date: December 10, 2020
    Inventors: Atsushi SUMASU, Shozo OKASAKA, Shinsuke TAKAOKA, Seigo NAKAO, Daichi IMAMURA
  • Patent number: 10849121
    Abstract: In the base station (100), a search space setting unit (103) sets a search space on the basis of a search space setting rule in accordance with R-PDCCH range of a setting target slot, and an allocating unit (108) places DCI in one of a plurality of candidates of to-be-decoded unit range included in the set search space. The search space setting rules are associated with respective numbers of candidates of to-be-decoded unit range corresponding to the respective ones of a plurality of numbers of connections for R-CCE, and a first search space setting rule of a slot 0 and a second search space setting rule of a slot 1 are different from each other in terms of the patterns related to the numbers of candidates of to-be-decoded unit range corresponding to the plurality of numbers of connections for R-CCE.
    Type: Grant
    Filed: February 10, 2020
    Date of Patent: November 24, 2020
    Assignee: SUN PATENT TRUST
    Inventors: Toru Oizumi, Seigo Nakao, Ayako Horiuchi
  • Patent number: 10833741
    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: February 28, 2020
    Date of Patent: November 10, 2020
    Assignee: Sun Patent Trust
    Inventors: Hui Tong, Masayuki Hoshino, Ming Xu, Seigo Nakao, Daichi Imamura
  • Patent number: 10826639
    Abstract: The present disclosure provides an orthogonal codes based code division multiplexing method of performing the code division multiplexing of demodulation reference signals in multiple layers of resource blocks by using orthogonal matrices, the method comprising: changing the order of chips in particular rows of a first orthogonal matrix to obtain a second orthogonal matrix with the changed order of chips; and multiplying the chips in respective rows of the second orthogonal matrix by the demodulation reference signals in corresponding layers of resource blocks correspondingly in the time direction to obtain code division multiplexing signals. The technical scheme of the present disclosure can improve the power jitter situation of downlink signals on the time, thereby the usage efficiency of the power amplifier at the base station side can be improved.
    Type: Grant
    Filed: March 28, 2019
    Date of Patent: November 3, 2020
    Assignee: Sun Patent Trust
    Inventors: Zhi Zhang, Ming Xu, Masayuki Hoshino, Seigo Nakao, Daichi Imamura
  • Patent number: 10826669
    Abstract: It is possible to improve the CQI reception performance even when a delay is caused in a propagation path, a transmission timing error is caused, or a residual interference is generated between cyclic shift amounts of different ZC sequences. For the second symbol and the sixth symbol of the ACK/NACK signal which are multiplexed by RS of CQI, (+, +) or (?, ?) is applied to a partial sequence of the Walsh sequence. For RS of CQI transmitted from a mobile station, + is added as an RS phase of the second symbol and ? is added as an RS phase of the sixth symbol. A base station (100) receives multiplexed signals of ACK/NACK signals and CQI signals transmitted from a plurality of mobile stations. An RS synthesis unit (119) performs synthesis by aligning the RS phase of CQI.
    Type: Grant
    Filed: November 16, 2018
    Date of Patent: November 3, 2020
    Assignee: Godo Kaisha IP Bridge 1
    Inventors: Seigo Nakao, Daichi Imamura, Yoshihiko Ogawa, Atsushi Matsumoto, Katsuhiko Hiramatsu
  • Patent number: 10826656
    Abstract: A wireless communication base station apparatus prevents degradation of throughput of LTE terminals, even when LTE terminals and LTE+ terminals are present together. A setting section sets in each subframe a resource block in which is arranged a reference signal that is employed solely by LTE+ terminals, based on the pattern of arrangement of reference signals employed solely by LTE+ terminals. As to symbols that are mapped to antennas (110-1) to (110-4), an arrangement section arranges the characteristic cell reference signals employed by both LTE terminals and LTE+ terminals in all of the resource blocks in a single frame. In contrast, as to symbols that are mapped to antennas (110-5) to (110-8), the arrangement section arranges in some of the resource blocks, that are set in accordance with the setting results input from a setting section, the characteristic cell reference signals that are employed solely by the LTE+ terminals.
    Type: Grant
    Filed: May 1, 2019
    Date of Patent: November 3, 2020
    Assignee: Sun Patent Trust
    Inventors: Akihiko Nishio, Seigo Nakao
  • Patent number: 10827482
    Abstract: In a terminal, a control unit transmits a bundle response signal using a resource in a basic region of an uplink control channel in an uplink unit band of a unit band group when no error is detected in each of a plurality of pieces of downlink data of the unit band group, the uplink control channel in the uplink unit band being associated with a downlink control channel in a basic unit band that is a downlink unit band in which a broadcast channel signal including information relating to the uplink unit band is transmitted, and the control unit transmits the bundle response signal using a resource in an additional region of the uplink control channel when an error is detected in each of the plurality of pieces of downlink data.
    Type: Grant
    Filed: November 14, 2019
    Date of Patent: November 3, 2020
    Assignee: Godo Kaisha IP Bridge 1
    Inventors: Seigo Nakao, Daichi Imamura
  • Patent number: 10826637
    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: Grant
    Filed: November 8, 2017
    Date of Patent: November 3, 2020
    Assignee: Panasonic Corporation
    Inventors: Seigo Nakao, Daichi Imamura, Katsuhiko Hiramatsu
  • Patent number: 10826666
    Abstract: This invention is directed to a terminal apparatus capable of preventing the degradation of reception quality of control information even in a case of employing SU-MIMO transmission system. A terminal (200), which uses a plurality of different layers to transmit two code words in which control information is placed, comprises: a resource amount determining unit (204) that determines, based on a lower one of the encoding rates of the two code words or based on the average value of the reciprocals of the encoding rates of the two code words, resource amounts of control information in the respective ones of the plurality of layers; and a transport signal forming unit (205) that places, in the two code words, the control information modulated by use of the resource amounts, thereby forming a transport signal.
    Type: Grant
    Filed: August 5, 2019
    Date of Patent: November 3, 2020
    Assignee: Sun Patent Trust
    Inventors: Yoshihiko Ogawa, Akihiko Nishio, Seigo Nakao
  • Publication number: 20200344768
    Abstract: A reception processor receives the cell detection reference signals, each of the cell detection reference signals being transmitted from corresponding one of a plurality of cells. An RRM report generator generates measurement information indicating a measurement result of reception quality measured using the cell detection reference signal. A transmission processor transmits the measurement information. The cell detection reference signals are mapped to any one of a plurality of candidate resources, which is a part of a plurality of resources set for other reference signals in a subframe to which the cell detection reference signals are mapped.
    Type: Application
    Filed: July 10, 2020
    Publication date: October 29, 2020
    Inventors: Masayuki Hoshino, Ayako Horiuchi, Seigo Nakao
  • Publication number: 20200337082
    Abstract: Provided are a terminal, a base station and a signal transmission control method whereby a response signal can be efficiently transmitted when the terminal receives downstream allocation control information via an R-PDCCH. An extraction unit receives downstream control information via one of a first downstream control channel, which is transmitted by use of one or more control channel elements (CCE) associated with an upstream control channel resource, and a second downstream control channel different from the first downstream control channel, and also receives data via a data channel. A control unit selects, from resources associated with CCE and from particular resources reported by a base station, an upstream control channel resource to be used in transmission of the response signal, and controls the transmission of the response signal.
    Type: Application
    Filed: July 6, 2020
    Publication date: October 22, 2020
    Inventor: Seigo Nakao
  • Publication number: 20200337033
    Abstract: Provided are a base station, whereby the erroneous detection of control information can be reduced, thereby preventing the degradation of the system throughput. A base station maps a downstream allocation control information unit, which is addressed to a terminal, to a first resource region, which can be used for any of a downstream control channel region and a downstream data channel region, or to a second resource region, which can be used only for the downstream control channel, so as to transmit the downstream allocation control information unit. In the base station, a control unit establishes a scale of the PDCCH region, and a transmission region establishing unit establishes, on the basis of a scale value established by the control unit, a mapping region to which the DCI is mapped within the R-PDCCH region and the PDCCH region.
    Type: Application
    Filed: July 2, 2020
    Publication date: October 22, 2020
    Inventors: Akihiko Nishio, Seigo Nakao, Ayako Horiuchi, Yasuaki Yuda, Sujuan Feng, Michael Einhaus
  • Patent number: 10813096
    Abstract: A wireless communication terminal apparatus wherein even when a SC-FDMA signal is divided into a plurality of clusters and the plurality of clusters are then mapped to respective discontinuous frequency bands (when C-SC-FDMA is used), the improvement effect of system throughput can be maintained, while the user throughput can be improved. In the apparatus, a DFT unit (210) subjects a symbol sequence of time domain to a DFT process, thereby generating signals of frequency domain. A setting unit (211) divides the signals input from the DFT unit (210) into a plurality of clusters according to a cluster pattern that is in accordance with an MCS set, an encoding size, or the number of Ranks occurring during MIMO transmissions, which is indicated in those signals input, and then maps the plurality of clusters to the respective ones of a plurality of discontinuous frequency resources, thereby setting a constellation of the plurality of clusters in the frequency domain.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: October 20, 2020
    Assignee: Sun Patent Trust
    Inventors: Shinsuke Takaoka, Seigo Nakao, Daichi Imamura, Masayuki Hoshino
  • Patent number: 10790923
    Abstract: A terminal apparatus is disclosed wherein even in a case of applying SU-MIMO and MU-MIMO at the same time, the inter-sequence interference in a plurality of pilot signals used by the same terminal can be suppressed to a low value, while the inter-sequence interference in pilot signal between terminals can be reduced. In this terminal apparatus: a pilot information deciding unit decides, based on allocation control information, Walsh sequences of the respective ones of first and second stream groups at least one of which includes a plurality of streams; and a pilot signal generating unit forms a transport signal by using the decided Walsh sequences to spread the streams included in the first and second stream groups. During this, Walsh sequences orthogonal to each other are established in the first and second stream groups, and users are allocated on a stream group-by-stream group basis.
    Type: Grant
    Filed: July 1, 2019
    Date of Patent: September 29, 2020
    Assignee: Sun Patent Trust
    Inventors: Yoshihiko Ogawa, Akihiko Nishio, Takashi Iwai, Seigo Nakao, Daichi Imamura, Atsushi Sumasu
  • Patent number: 10791570
    Abstract: A base station able to maintain backward compatibility with an LTE mobile station while minimizing the amount of increase in uplink scheduling information reception and demodulation/decoding processing in independent uplink/downlink cell data transmission. A wireless communication system includes a cell #1, a cell #2, and an LTE-A mobile station, and supports independent uplink/downlink cell data transmission. The base station of the cell #2 arranges a PDCCH+, which includes uplink scheduling information from the LTE-A mobile station to the base station of the cell #2, in a downlink data region in the downlink connection of the base station of the cell #1.
    Type: Grant
    Filed: May 1, 2019
    Date of Patent: September 29, 2020
    Assignee: SUN PATENT TRUST
    Inventors: Atsushi Sumasu, Shozo Okasaka, Shinsuke Takaoka, Seigo Nakao, Daichi Imamura
  • Publication number: 20200305185
    Abstract: Communication apparatuses and methods reduce the amount of signaling while maintaining a high scheduling gain. A determination unit stores a correspondence between the number of code words and the number of clusters to reduce the maximum value for the number of clusters allocated to each terminal as the number of code words increases, and thus determines the maximum value for the number of clusters based on the number of code words acquired. Based on the number of code words for a transmission signal from a terminal, an estimated value for the reception quality that is output by an estimation unit, and the maximum value for the number of clusters that is output by the determination unit, a scheduling unit schedules the allocation of the transmission signal transmitted by each terminal to a transmission band frequency (frequency resource) so as not to exceed the maximum value for the number of clusters.
    Type: Application
    Filed: June 9, 2020
    Publication date: September 24, 2020
    Inventors: Yoshihiko OGAWA, Akihiko NISHIO, Daichi IMAMURA, Seigo NAKAO, Masayuki HOSHINO, Takashi IWAI, Sadaki FUTAGI
  • Publication number: 20200304254
    Abstract: Disclosed are a wireless base station, wireless terminal, and channel signal formation method that can prevent the quality of downstream assignment control data from degrading, while preventing the number of blind determinations from increasing on the wireless terminal on the receiving side of the downstream control channel signal. In a base station (100), a control unit (101) and a data size regulation unit (103) control the data size of downstream assignment control data and upstream assignment control data contained in the PDCCH signal based on the communication format used between the base station (100) and a terminal (200), the number of antennas (M) (nonnegative number) on the base station (100), the number of antennas (N) (nonnegative number) on the terminal (200), the bandwidth of the downstream band, and the bandwidth of the upstream band.
    Type: Application
    Filed: June 5, 2020
    Publication date: September 24, 2020
    Inventors: Seigo NAKAO, Akihiko NISHIO, Daichi IMAMURA
  • Publication number: 20200296689
    Abstract: Provided is a radio communication terminal which is capable of measuring quality in communication with a handover destination with high accuracy. The radio communication terminal is capable of communicating with a base station or a relay node, and includes: a receiver which receives control information including information relating to measurement of measuring quality of a neighbor cell; an extractor which extracts information on a subframe where the measurement should be performed, which is a subframe where only transmission of a signal from the relay node connected to the base station is performed, from the information relating to the measurement; a measurement section which performs the measurement, on a subframe basis, based on the extracted information on the subframe where the measurement should be performed; and a transmitter which transmits a result of the measurement to the base station or the relay node.
    Type: Application
    Filed: May 29, 2020
    Publication date: September 17, 2020
    Inventors: Yasuaki Yuda, Seigo Nakao, Ayako Horiuchi, Akihiko Nishio, Daichi Imamura, Kenichi Miyoshi