Patents by Inventor Masatsugu Higashinaka

Masatsugu Higashinaka 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: 11336317
    Abstract: A radio communication system according to the present invention is a radio communication system including a transmission device and a reception device, the transmission device includes a first null insertion unit that inserts a first signal that is a signal having an electric power lower than an amplitude of the data symbols, in a time direction of data symbols, and the reception device includes a null extraction unit that extracts a first symbol that is a signal in a period corresponding to the first signal, from a received signal, a signal interpolation unit that interpolates the first symbol to reproduce interference components in periods corresponding to the data symbols, and a subtraction unit that subtracts the interference components from the received signal.
    Type: Grant
    Filed: February 27, 2018
    Date of Patent: May 17, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventors: Koji Tomitsuka, Masatsugu Higashinaka, Hiroyasu Sano
  • Patent number: 11329859
    Abstract: A transmitter includes: a phase rotation sequence generation unit that generates, on the basis of transmit bits being input, a phase rotation sequence in which a frequency response has a bandwidth; an up-sampling unit that changes a sample rate of the phase rotation sequence and further replicates the phase rotation sequence; and a frequency shift unit that shifts, by a specified amount of shift on a frequency axis, a frequency component of the phase rotation sequence acquired from the up-sampling unit.
    Type: Grant
    Filed: February 27, 2018
    Date of Patent: May 10, 2022
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Masatsugu Higashinaka, Hiroyasu Sano
  • Publication number: 20220131565
    Abstract: A receiving apparatus includes: a receiving module that is a fixed circuit whose internal processing procedure is not able to be changed, the receiving module performing demodulation processing on a reception signal to generate a binary hard decision sequence; and an external reception controller including a receiving module controller to control the receiving module, and a redundancy decoder to redundantly decode the binary hard decision sequence output from the receiving module for conversion into a multilevel sequence, wherein the redundancy decoder redundantly decodes the binary hard decision sequence by combining values weighted based on reliability.
    Type: Application
    Filed: January 10, 2022
    Publication date: April 28, 2022
    Applicant: Mitsubishi Electric Corporation
    Inventors: Akinori NAKAJIMA, Masatsugu HIGASHINAKA
  • Patent number: 11290312
    Abstract: A transmission apparatus that transmits a block signal including a plurality of data symbols, includes: a data-symbol generation unit that generates a data symbol; a symbol arrangement unit that arranges the data symbol and a same-quadrant symbol such that one same-quadrant symbol that becomes a signal point in a same quadrant in a complex plane is inserted per block at a predetermined position in each block signal to generate a block symbol; a CP insertion unit that inserts a Cyclic Prefix into the block symbol; and an interpolation unit that performs interpolation processing on the block symbol on which CP insertion has been performed.
    Type: Grant
    Filed: March 27, 2020
    Date of Patent: March 29, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventors: Fumihiro Hasegawa, Hiroshi Nishimoto, Akihiro Okazaki, Masatsugu Higashinaka
  • Publication number: 20210344443
    Abstract: A system includes: a transmitter including: a coding unit generating a first bit sequence by convolutional coding on information bits based on a code rate; a bit erasing unit generating a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits; and a modulation unit generating a symbol by modulation using the second bit sequence; and a receiver including: a demodulation unit calculating first reliabilities that can be derived from the symbol; a likelihood extension unit generating extended bit sequences each composed of bits for the first number of bits, and generating a plurality of second reliabilities by assigning first reliabilities duplicated, as the reliabilities of the extended bit sequences; and a decoding unit creating a trellis diagram using the code rate and the extended bit sequences, and assigning the second reliabilities to branches of the trellis diagram.
    Type: Application
    Filed: July 12, 2021
    Publication date: November 4, 2021
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Masatsugu HIGASHINAKA
  • Publication number: 20210135698
    Abstract: A radio communication system according to the present invention is a radio communication system including a transmission device and a reception device, the transmission device includes a first null insertion unit that inserts a first signal that is a signal having an electric power lower than an amplitude of the data symbols, in a time direction of data symbols, and the reception device includes a null extraction unit that extracts a first symbol that is a signal in a period corresponding to the first signal, from a received signal, a signal interpolation unit that interpolates the first symbol to reproduce interference components in periods corresponding to the data symbols, and a subtraction unit that subtracts the interference components from the received signal.
    Type: Application
    Filed: February 27, 2018
    Publication date: May 6, 2021
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji TOMITSUKA, Masatsugu HIGASHINAKA, Hiroyasu SANO
  • Publication number: 20200403841
    Abstract: A transmitter includes: a phase rotation sequence generation unit that generates, on the basis of transmit bits being input, a phase rotation sequence in which a frequency response has a bandwidth; an up-sampling unit that changes a sample rate of the phase rotation sequence and further replicates the phase rotation sequence; and a frequency shift unit that shifts, by a specified amount of shift on a frequency axis, a frequency component of the phase rotation sequence acquired from the up-sampling unit.
    Type: Application
    Filed: February 27, 2018
    Publication date: December 24, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masatsugu HIGASHINAKA, Hiroyasu SANO
  • Patent number: 10873487
    Abstract: A communication device includes a signal determiner determining whether there is a reception signal, and a period estimator estimating an interruption period of interruption of a signal transmitted from a device as a source of the reception signal, using a determination result from the signal determiner.
    Type: Grant
    Filed: August 18, 2020
    Date of Patent: December 22, 2020
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Akinori Ohashi, Masatsugu Higashinaka, Shusaku Umeda
  • Publication number: 20200382350
    Abstract: A communication device includes a signal determiner determining whether there is a reception signal, and a period estimator estimating an interruption period of interruption of a signal transmitted from a device as a source of the reception signal, using a determination result from the signal determiner.
    Type: Application
    Filed: August 18, 2020
    Publication date: December 3, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Akinori OHASHI, Masatsugu HIGASHINAKA, Shusaku UMEDA
  • Publication number: 20200228378
    Abstract: A transmission apparatus that transmits a block signal including a plurality of data symbols, includes: a data-symbol generation unit that generates a data symbol; a symbol arrangement unit that arranges the data symbol and a same-quadrant symbol such that one same-quadrant symbol that becomes a signal point in a same quadrant in a complex plane is inserted per block at a predetermined position in each block signal to generate a block symbol; a CP insertion unit that inserts a Cyclic Prefix into the block symbol; and an interpolation unit that performs interpolation processing on the block symbol on which CP insertion has been performed.
    Type: Application
    Filed: March 27, 2020
    Publication date: July 16, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Fumihiro HASEGAWA, Hiroshi NISHIMOTO, Akihiro OKAZAKI, Masatsugu HIGASHINAKA
  • Patent number: 10680666
    Abstract: A timing estimation device according to the present invention includes a received signal memory that outputs a plurality of sample groups each of which is a first number of samples extracted at symbol rate intervals from an oversampled received signal containing a known sequence, with shifting their leading positions by one sample from each other, a reliability calculation unit that calculates a channel impulse response for each of the sample groups, based on the sample group, generates a replica of the received signal using the channel impulse response and the known sequence, and calculates a reliability value based on the sample group, the replica, and the channel impulse response, and a timing estimation unit that estimates a preceding wave arrival timing and a delayed wave arrival timing, based on the reliability value.
    Type: Grant
    Filed: February 27, 2017
    Date of Patent: June 9, 2020
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takeshi Kawamoto, Takehiko Nishide, Koji Tomitsuka, Masatsugu Higashinaka
  • Patent number: 10666299
    Abstract: A maximum likelihood sequence estimation circuit includes: a signal extraction unit that estimates a reception sample signal including a preceding wave component and a reception sample signal including a delayed wave component from a plurality of reception sample signals sampled from a reception signal at sample intervals shorter than symbol intervals, and extracts, based on an estimation result, both first reception sample signals and second reception sample signals from the plurality of reception sample signals at the symbol intervals; and a maximum likelihood sequence estimation unit that estimates a maximum likelihood sequence using the first reception sample signals extracted and the second reception sample signals extracted.
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: May 26, 2020
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takehiko Nishide, Masatsugu Higashinaka, Koji Tomitsuka
  • Patent number: 10644920
    Abstract: A transmission apparatus that transmits a block signal including a plurality of data symbols, includes: a data-symbol generation unit that generates a data symbol; a symbol arrangement unit that arranges the data symbol and a same-quadrant symbol such that one same-quadrant symbol that becomes a signal point in a same quadrant in a complex plane is inserted per block at a predetermined position in each block signal to generate a block symbol; a CP insertion unit that inserts a Cyclic Prefix into the block symbol; and an interpolation unit that performs interpolation processing on the block symbol on which CP insertion has been performed.
    Type: Grant
    Filed: February 1, 2018
    Date of Patent: May 5, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Fumihiro Hasegawa, Hiroshi Nishimoto, Akihiro Okazaki, Masatsugu Higashinaka
  • Publication number: 20190393910
    Abstract: A timing estimation device according to the present invention includes a received signal memory that outputs a plurality of sample groups each of which is a first number of samples extracted at symbol rate intervals from an oversampled received signal containing a known sequence, with shifting their leading positions by one sample from each other, a reliability calculation unit that calculates a channel impulse response for each of the sample groups, based on the sample group, generates a replica of the received signal using the channel impulse response and the known sequence, and calculates a reliability value based on the sample group, the replica, and the channel impulse response, and a timing estimation unit that estimates a preceding wave arrival timing and a delayed wave arrival timing, based on the reliability value.
    Type: Application
    Filed: February 27, 2017
    Publication date: December 26, 2019
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takeshi Kawamoto, Takehiko Nishide, Koji Tomitsuka, Masatsugu Higashinaka
  • Publication number: 20190372606
    Abstract: A maximum likelihood sequence estimation circuit includes: a signal extraction unit that estimates a reception sample signal including a preceding wave component and a reception sample signal including a delayed wave component from a plurality of reception sample signals sampled from a reception signal at sample intervals shorter than symbol intervals, and extracts, based on an estimation result, both first reception sample signals and second reception sample signals from the plurality of reception sample signals at the symbol intervals; and a maximum likelihood sequence estimation unit that estimates a maximum likelihood sequence using the first reception sample signals extracted and the second reception sample signals extracted.
    Type: Application
    Filed: December 9, 2016
    Publication date: December 5, 2019
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takehiko NISHIDE, Masatsugu HIGASHINAKA, Koji TOMITSUKA
  • Patent number: 10122556
    Abstract: A transmitter for use in a communication system uses a orthogonal modulation method, and the transmitter includes: an orthogonal sequence prescriber that prescribes association between orthogonal signals and information words determined on the basis of sizes of differences between information words of a plurality of mutually different information words and a probability of occurrence of decision errors between orthogonal signals of a plurality of mutually orthogonal signals; and a symbol mapper that, upon input of any of the information words, generates modulation symbols based on the orthogonal signals associated with the input information word according to the associations prescribed by the orthogonal sequence prescriber.
    Type: Grant
    Filed: September 7, 2015
    Date of Patent: November 6, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventor: Masatsugu Higashinaka
  • Publication number: 20180254934
    Abstract: A transmitter for use in a communication system uses a orthogonal modulation method, and the transmitter includes: an orthogonal sequence prescriber 12 that prescribes association between orthogonal signals and information words determined on the basis of sizes of differences between information words of a plurality of mutually different information words and a probability of occurrence of decision errors between orthogonal signals of a plurality of mutually orthogonal signals; and a symbol mapper 11 that, upon input of any of the information words, generates modulation symbols based on the orthogonal signals associated with the input information word according to the associations prescribed by the orthogonal sequence prescriber.
    Type: Application
    Filed: May 2, 2018
    Publication date: September 6, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventor: Masatsugu HIGASHINAKA
  • Publication number: 20180159712
    Abstract: A transmission apparatus that transmits a block signal including a plurality of data symbols, includes: a data-symbol generation unit that generates a data symbol; a symbol arrangement unit that arranges the data symbol and a same-quadrant symbol such that one same-quadrant symbol that becomes a signal point in a same quadrant in a complex plane is inserted per block at a predetermined position in each block signal to generate a block symbol; a CP insertion unit that inserts a Cyclic Prefix into the block symbol; and an interpolation unit that performs interpolation processing on the block symbol on which CP insertion has been performed.
    Type: Application
    Filed: February 1, 2018
    Publication date: June 7, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Fumihiro Hasegawa, Hiroshi Nishimoto, Akihiro Okazaki, Masatsugu Higashinaka
  • Patent number: 9917716
    Abstract: A transmission apparatus that transmits a block signal including a plurality of data symbols, includes: a data-symbol generation unit that generates a data symbol; a symbol arrangement unit that arranges the data symbol and a same-quadrant symbol such that one same-quadrant symbol that becomes a signal point in a same quadrant in a complex plane is inserted per block at a predetermined position in each block signal to generate a block symbol; a CP insertion unit that inserts a Cyclic Prefix into the block symbol; and an interpolation unit that performs interpolation processing on the block symbol on which CP insertion has been performed.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: March 13, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Fumihiro Hasegawa, Hiroshi Nishimoto, Akihiro Okazaki, Masatsugu Higashinaka
  • Patent number: 9866419
    Abstract: A transmission apparatus that transmits a block signal including a plurality of data symbols, includes a data-symbol generation unit that generates data symbols; a fixed-symbol arrangement unit that arranges a data symbol and a fixed symbol such that the fixed symbol is inserted at a predetermined position in the block signal to generate a block symbol; an interpolation unit that performs interpolation processing on the block symbol; and a CP insertion unit that inserts a Cyclic Prefix into a signal on which the interpolation processing has been performed to generate the block signal.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: January 9, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Fumihiro Hasegawa, Hiroshi Nishimoto, Masatsugu Higashinaka, Akihiro Okazaki