Patents by Inventor Kenta Imaizumi

Kenta Imaizumi 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: 11875774
    Abstract: Provided is a sound image localizing device, a sound image localizing method, and a program that enable a virtual speaker to reproduce sound in a wide frequency band with high sound quality. A sound image localizing device 10 includes a directivity control filter design unit 11 that computes a directivity control filter from a desired directional characteristic, a filter coefficient correction unit 12 that corrects the directivity control filter computed by the directivity control filter design unit 11, and a convolution operation unit 13 that computes an output acoustic signal by performing convolution of an input acoustic signal and the directivity control filter corrected by the filter coefficient correction unit 12.
    Type: Grant
    Filed: January 17, 2020
    Date of Patent: January 16, 2024
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kenta Imaizumi, Kimitaka Tsutsumi, Atsushi Nakadaira
  • Patent number: 11871181
    Abstract: The scale of an apparatus that reproduces a sound field is reduced. A speaker array 1 includes a plurality of speakers arranged at intersections of a first plurality of virtual lines arranged parallel to each other at equal intervals and a second plurality of virtual lines that are perpendicular to the first plurality of virtual lines and are arranged parallel to each other at equal intervals, wherein multipoles of a given order are superimposed using the plurality of speakers to realize wave field synthesis.
    Type: Grant
    Filed: July 22, 2020
    Date of Patent: January 9, 2024
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kimitaka Tsutsumi, Kenta Imaizumi, Atsushi Nakadaira, Yoichi Haneda
  • Patent number: 11871211
    Abstract: A signal processing device 1 includes an expansion coefficient calculation unit 11 that, from an outward sound field to be reproduced, calculates a spherical harmonics expansion coefficient for reproducing the sound field; an expansion coefficient conversion unit 12 that converts the calculated spherical harmonics expansion coefficient into a weight factor for superposition of multipole sources; a filter coefficient calculation unit 13 that, from the weight factor, calculates a filter coefficient corresponding to each speaker included in a multipole speaker array, the speaker providing output outwardly; and a convolution operation unit 14 that convolves the filter coefficient corresponding to each speaker into an input acoustic signal to calculate an output acoustic signal for each speaker.
    Type: Grant
    Filed: August 29, 2019
    Date of Patent: January 9, 2024
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kenta Imaizumi, Kimitaka Tsutsumi, Atsushi Nakadaira
  • Publication number: 20230419945
    Abstract: A sound image localizing device includes a directivity control filter design unit that computes a directivity control filter from a desired directional characteristic, a filter coefficient correction unit that corrects the directivity control filter computed by the directivity control filter design unit, and a convolution operation unit that computes an output acoustic signal by performing convolution of an input acoustic signal and the directivity control filter corrected by the filter coefficient correction unit. Filters that respectively correspond to speakers constituting a speaker array are computed by the directivity control filter design unit and the filter coefficient correction unit, an acoustic beam is generated using directivity control by the speaker array, and the acoustic beam is caused to be reflected from a wall surface or a ceiling to generate a virtual sound source.
    Type: Application
    Filed: September 12, 2023
    Publication date: December 28, 2023
    Inventors: Kenta Imaizumi, Kimitaka TSUTSUMI, Atsushi Nakadaira
  • Publication number: 20220407609
    Abstract: A sound field generation apparatus includes: a first modulation unit 10 that modulates an ultrasonic wave signal according to a prescribed modulation system; a second modulation unit 30 that modulates the ultrasonic wave signal ?0 according to a modulation system different from the modulation system of the first modulation unit 10; a filter unit 20 that changes frequency characteristics of an audible range signal s(t) used in modulation of the second modulation unit 30; a first ultrasonic wave output unit 40 that outputs a first ultrasonic wave signal y-(t) modulated by the first modulation unit 10; and a second ultrasonic wave output unit 50 that outputs a second ultrasonic wave signal y˜(t) modulated by the second modulation unit 30, wherein the filter unit 20 is set to have filter characteristics to cancel a first audible sound y-(t) reproduced by the first ultrasonic wave signal y-(t) with a second audible sound y˜(t) reproduced by the second ultrasonic wave signal y˜(t) at a control point 70 provided out
    Type: Application
    Filed: November 8, 2019
    Publication date: December 22, 2022
    Inventors: Kimitaka TSUTSUMI, Kenta IMAIZUMI, Takashi SATO
  • Publication number: 20220321998
    Abstract: The scale of an apparatus that reproduces a sound field is reduced. A speaker array 1 includes a plurality of speakers arranged at intersections of a first plurality of virtual lines arranged parallel to each other at equal intervals and a second plurality of virtual lines that are perpendicular to the first plurality of virtual lines and are arranged parallel to each other at equal intervals, wherein multipoles of a given order are superimposed using the plurality of speakers to realize wave field synthesis.
    Type: Application
    Filed: July 22, 2020
    Publication date: October 6, 2022
    Inventors: Kimitaka TSUTSUMI, Kenta IMAIZUMI, Atsushi NAKADAIRA, Yoichi HANEDA
  • Publication number: 20220312145
    Abstract: A signal processing device 1 includes an expansion coefficient calculation unit 11 that, from an outward sound field to be reproduced, calculates a spherical harmonics expansion coefficient for reproducing the sound field; an expansion coefficient conversion unit 12 that converts the calculated spherical harmonics expansion coefficient into a weight factor for superposition of multipole sources; a filter coefficient calculation unit 13 that, from the weight factor, calculates a filter coefficient corresponding to each speaker included in a multipole speaker array, the speaker providing output outwardly; and a convolution operation unit 14 that convolves the filter coefficient corresponding to each speaker into an input acoustic signal to calculate an output acoustic signal for each speaker.
    Type: Application
    Filed: August 29, 2019
    Publication date: September 29, 2022
    Inventors: Kenta IMAIZUMI, Kimitaka TSUTSUMI, Atsushi NAKADAIRA
  • Publication number: 20220157292
    Abstract: Provided is a sound image localization device capable of flexibly controlling directivity with a short calculation time. A sound image localization device that reflects, on a reflector 50, a sound signal radiated from a speaker array 40 arranged with a plurality of speakers SP1 to SPQ on a straight line to localize a sound image includes an expansion coefficient calculation unit 10 configured to analytically calculate expansion coefficients by performing a spherical harmonic function expansion on a window function representing desired directivity, a filter coefficient generation unit 20 configured to convert the expansion coefficients into filter coefficients corresponding to each of the speakers SP1 to SPQ, and a speaker drive unit 30 configured to generate a speaker drive signal for driving each of the speakers SP1 to SPQ by convolving the filter coefficients in a voice signal.
    Type: Application
    Filed: March 19, 2020
    Publication date: May 19, 2022
    Inventors: Kenta IMAIZUMI, Kimitaka TSUTSUMI, Atsushi NAKADAIRA
  • Publication number: 20220101825
    Abstract: Provided is a sound image localizing device, a sound image localizing method, and a program that enable a virtual speaker to reproduce sound in a wide frequency band with high sound quality. A sound image localizing device 10 includes a directivity control filter design unit 11 that computes a directivity control filter from a desired directional characteristic, a filter coefficient correction unit 12 that corrects the directivity control filter computed by the directivity control filter design unit 11, and a convolution operation unit 13 that computes an output acoustic signal by performing convolution of an input acoustic signal and the directivity control filter corrected by the filter coefficient correction unit 12.
    Type: Application
    Filed: January 17, 2020
    Publication date: March 31, 2022
    Inventors: Kenta Imaizumi, Kimitaka TSUTSUMI, Atsushi Nakadaira