Patents by Inventor Masafumi Yoshioka

Masafumi Yoshioka 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: 20220294506
    Abstract: A transmitting station device at least comprises a training signal generation unit, and a receiving station device at least comprises a communication path estimation unit which estimates a communication path response from the known signal, and a beam forming unit which performs a beam forming process using a weight to suppress inter-stream interference, a channel fluctuation amount calculation unit which calculates as a channel fluctuation amount a difference between the communication path responses estimated in a manner of one following another in time, and a weight calculation unit which calculates a new weight using an updated value of the weight calculated based on the channel fluctuation amount are included in one of the transmitting station device and the receiving station device. This can significantly reduce the amount of calculation related to update of a weight.
    Type: Application
    Filed: September 6, 2019
    Publication date: September 15, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita KURIYAMA, Hayato FUKUZONO, Masafumi YOSHIOKA, Tsutomu TATSUTA
  • Publication number: 20220278721
    Abstract: A transmission station device includes a training signal generation unit, a CP addition unit, and a transmission beamforming unit that performs transmission beamforming processing in a time domain using a transmission weight for removing inter-antenna interference. A reception station device includes a CP removal unit, a channel estimation unit, and an equalization unit that performs equalization processing for removing inter-symbol interference in a frequency domain using a reception weight. Either of the transmission station device or the reception station device is provided with a weight calculation unit that calculates the transmission weight and the reception weight based on the channel response, an effective CIR length calculation unit that calculates an effective CIR length between antennas, and a CP length setting unit that sets, to the CP length, a maximum CIR length among the CIR lengths of respective items of the reception weight.
    Type: Application
    Filed: August 21, 2019
    Publication date: September 1, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hayato FUKUZONO, Keita KURIYAMA, Masafumi YOSHIOKA, Tsutomu TATSUTA
  • Publication number: 20220216900
    Abstract: According to the present invention, in a wireless communication system that performs single carrier MIMO transmission between a transmitting station device and a receiving station device, the transmitting station device includes a time-domain linear equalization unit, a propagation path characteristics estimation unit configured to receive a training signal and estimate a transfer function matrix of propagation path characteristics, a filter tap calculation unit configured to calculate filter tap coefficients for the time-domain linear equalization unit based on the transfer function matrix by a predefined approach, and a transmission mode determination unit configured to make the filter tap calculation unit calculate the filter tap coefficients when the transfer function matrix meets a predefined condition, and to change a transmission mode and determine the transmission mode that meets the predefined condition when the transfer function matrix does not meet the predefined condition.
    Type: Application
    Filed: March 26, 2020
    Publication date: July 7, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita KURIYAMA, Hayato FUKUZONO, Masafumi YOSHIOKA, Tsutomu TATSUTA
  • Publication number: 20220209830
    Abstract: According to the present invention, in a wireless communication system that performs single carrier MIMO transmission between a transmitting station device and a receiving station device, the transmitting station device including: a time-domain linear equalization unit configured to remove inter-symbol interference and inter-stream interference from a data signal to be transmitted to the receiving station device; a propagation path characteristics estimation unit configured to receive a training signal which is transmitted by the receiving station device and estimate a transfer function matrix of propagation path characteristics; and a filter tap calculation unit configured to calculate filter tap coefficients for the time-domain linear equalization unit by representing the estimated transfer function matrix as a matrix polynomial, taking an inverse response of the matrix polynomial as a transmit weight matrix, and approximating the transmit weight matrix with Neumann series, and the receiving station device
    Type: Application
    Filed: March 26, 2020
    Publication date: June 30, 2022
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita KURIYAMA, Hayato FUKUZONO, Masafumi YOSHIOKA, Tsutomu TATSUTA
  • Patent number: 11283492
    Abstract: According to the present invention, a transmitting station apparatus includes: a plurality of modulation units that modulates a plurality of streams into which transmission data is divided to generate a plurality of first data signals; a training signal generation unit that generates a known training signal; a linear equalization unit that linearly equalizes the plurality of first data signals using a tap coefficient for removing inter-antenna interference and inter-symbol interference and outputs second data signals on which transmission beam forming and equalization are simultaneously performed; and a plurality of transmitting station communication units that transmit the training signal or the second data signals to a receiving station apparatus and receive the tap coefficient from the receiving station apparatus, and a receiving station apparatus includes: a coefficient estimation unit that estimates a channel impulse response from the training signal and calculates the tap coefficient based on the channe
    Type: Grant
    Filed: October 18, 2019
    Date of Patent: March 22, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita Kuriyama, Hayato Fukuzono, Masafumi Yoshioka, Tsutomu Tatsuta
  • Patent number: 11265056
    Abstract: A radio communication system includes a transmitting station, and at least one receiving apparatus.
    Type: Grant
    Filed: July 23, 2019
    Date of Patent: March 1, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hayato Fukuzono, Keita Kuriyama, Toshio Ito, Shuta Ueno, Masafumi Yoshioka, Tsutomu Tatsuta, Hiroyuki Nakamura
  • Publication number: 20210359727
    Abstract: According to the present invention, a transmitting station apparatus includes: a plurality of modulation units that modulates a plurality of streams into which transmission data is divided to generate a plurality of first data signals; a training signal generation unit that generates a known training signal; a linear equalization unit that linearly equalizes the plurality of first data signals using a tap coefficient for removing inter-antenna interference and inter-symbol interference and outputs second data signals on which transmission beam forming and equalization are simultaneously performed; and a plurality of transmitting station communication units that transmit the training signal or the second data signals to a receiving station apparatus and receive the tap coefficient from the receiving station apparatus, and a receiving station apparatus includes: a coefficient estimation unit that estimates a channel impulse response from the training signal and calculates the tap coefficient based on the channe
    Type: Application
    Filed: October 18, 2019
    Publication date: November 18, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita KURIYAMA, Hayato FUKUZONO, Masafumi YOSHIOKA, Tsutomu TATSUTA
  • Publication number: 20210273705
    Abstract: A radio communication system includes a transmitting station, and at least one receiving apparatus.
    Type: Application
    Filed: July 23, 2019
    Publication date: September 2, 2021
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Hayato FUKUZONO, Keita KURIYAMA, Toshio ITO, Shuta UENO, Masafumi YOSHIOKA, Tsutomu TATSUTA, Hiroyuki NAKAMURA
  • Publication number: 20060280204
    Abstract: A first communication node, which transmits a packet including a data field and an FCS field, selectively transmits, to a second communication node, a first packet containing, in the FCS field, a first error detection code generated by performing a prescribed error detection code operation on a transmission packet or a second packet containing, in the FCS field, a second error detection code obtained by performing a prescribed operation on the first error detection code.
    Type: Application
    Filed: August 20, 2004
    Publication date: December 14, 2006
    Inventors: Kengo Nagata, Tomoaki Kumagai, Shinya Otsuki, Kazuyoshi Saito, Satoru Aikawa, Masafumi Yoshioka
  • Patent number: 6330699
    Abstract: An object of the present invention is to improve the transmission efficiency and reduce circuit size in error compensating techniques where bit errors occurring during transmission are compensated for by retransmission. Transmission equipment get sequence number(s) from control information and sequence numbers which follows from the sequence number which correspond to newest data packet amongst the sequence numbers. and transmits data packet corresponding to these sequence numbers at a predetermined timing. On the other hand, reception equipment receives data packet from the transmission equipment, and manages the sequence numbers of not yet received data packets. The reception equipment then sends back sequence number(s) of predetermined number, which is smaller number than the maximum number of data packets which is sent from transmission equipment at a predetermined timing, which correspond to not yet received data packet as control Information for each predetermined timing.
    Type: Grant
    Filed: July 28, 2000
    Date of Patent: December 11, 2001
    Assignee: Nippon Telegraph & Telephone Corporation
    Inventors: Masafumi Yoshioka, Atsushi Ohta, Masahiro Umehira
  • Patent number: 6163861
    Abstract: An object of the present invention is to improve the transmission efficiency and reduce circuit size in error compensating techniques where bit errors occurring during transmission are compensated for by retransmission.Transmission equipment get sequence number(s) from control information and sequence numbers which follows from the sequence number which correspond to newest data packet amongst the sequence numbers, and transmits data packet corresponding to these sequence numbers at a predetermined timing. On the other hand, reception equipment receives data packet from the transmission equipment, and manages the sequence numbers of not yet received data packets. The reception equipment then sends back sequence number(s) of predetermined number, which is smaller number than the maximum number of data packets which is sent from transmission equipment at a predetermined timing, which correspond to not yet received data packet as control information for each predetermined timing.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: December 19, 2000
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masafumi Yoshioka, Atsushi Ohta, Masahiro Umehira