Patents by Inventor Koji Kushida

Koji Kushida 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: 8363845
    Abstract: A speaker array apparatus capable of performing directivity control with ease even when sound emission is performed based on audio signals of different frequency ranges. The speaker array apparatus includes a speaker unit for emitting high-frequency range sound, and another speaker unit for emitting low- and high-frequency range sound. A signal processed by a high pass filter is used for generation of both audio signals used by these speaker units to emit the high-frequency range sounds. Since both the audio signals are rotated in phase similarly to each other, the phases of audio signals supplied to both the speaker units are in coincidence with each other in high-frequency range, which makes it easy to carry out directivity control.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: January 29, 2013
    Assignee: Yamaha Corporation
    Inventors: Takashi Yamakawa, Kenichi Tamiya, Koji Kushida, Ken Iwayama
  • Patent number: 8331575
    Abstract: Calculation is performed for sound paths 112-1, 114-1 along which sounds emitted from a sound emitting point 104 in an acoustic space 102 are reflected and delivered to a sound receiving point 106. By the calculation, entering angles eR1, eR2 by which the sound paths enter the front side 106a of the sound receiving point 106 are obtained. Calculation is then performed to obtain angles by which respective speakers 52C, 52L, 52R, 52SR, 52SL of a 5.1 surround system are arranged in a listening room, with the front side 106a of the sound receiving point 106 centered thereon. Audio signals on the respective sound paths are distributed among channels for any two speakers. Consequently, sharp localization of sound images is achieved, requiring less calculation in simulating acoustic characteristics of the acoustic space 102 in which the sound emitting point 104 for emitting sounds and the sound receiving point 106 for receiving the sounds are placed.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: December 11, 2012
    Assignee: Yamaha Corporation
    Inventors: Toru Kitayama, Kenichi Tamiya, Koji Kushida
  • Patent number: 8331590
    Abstract: A delay time calculation apparatus enabling all the speaker units of a delay array type speaker array to contribute to formation of a combined wavefront. Sound receiving points for acoustic waves output from the speaker units are set within a target area for the acoustic waves. For each speaker unit, an average value of differences between distances between the sound receiving points for the speaker units and other speaker units and distances between the sound receiving points for the speaker units and the speaker units is determined, and an average value of differences between distances from the other speaker units to sound receiving points for the other speaker units and distances from the speaker units to the sound receiving points for the other speaker units is determined. An average of the average values is converted into a delay time, thereby determining the delay time for each speaker unit.
    Type: Grant
    Filed: November 4, 2009
    Date of Patent: December 11, 2012
    Assignee: Yamaha Corporation
    Inventors: Takashi Yamakawa, Koji Kushida
  • Patent number: 8275160
    Abstract: A delay time calculation apparatus that enables all of speaker units constituting a speaker array to contribute to the formation of a combined wavefront directed to an area specified by a user. The delay time calculation apparatus includes a delay time calculation unit that calculates delay times of delayed audio signals supplied to the speaker units such that a ratio at which an evaluation object area is occupied by an area to which an acoustic wave output from each speaker unit reaches earlier than acoustic waves output from the other speaker units falls within a predetermined range. The evaluation object area is a target area to which a combined wavefront of acoustic waves output from the speaker units is directed, or is a perspective projection image of the target area onto a predetermined evaluation plane.
    Type: Grant
    Filed: May 18, 2009
    Date of Patent: September 25, 2012
    Assignee: Yamaha Corporation
    Inventors: Koji Kushida, Takashi Yamakawa
  • Patent number: 8218787
    Abstract: A microphone array signal processing apparatus which is capable of picking up sound in a low frequency band even with a compact microphone array. The microphone array signal processing apparatus is comprised of delay devices (411-1 to 411-M) that add delays to the respective ones of a plurality of sound signals output from the respective ones of a plurality of microphones constituting the microphone array, an adder (412) that sums the plurality of sound signals with the respective delays added thereto, a harmonic structure detecting section (421) that detects a harmonic structure of sound included in the sound signal, and a filtering processing section (422) that selectively passes predetermined frequency components based upon the detected harmonic structure.
    Type: Grant
    Filed: April 2, 2010
    Date of Patent: July 10, 2012
    Assignee: Yamaha Corporation
    Inventor: Koji Kushida
  • Patent number: 8160732
    Abstract: In a method for suppressing a noise by the spectrum subtraction method, it is possible to improve the noise suppression capability by simultaneously obtaining a frequency resolution required for the noise estimation spectrum and a temporal resolution required for the noise suppression spectrum. The signal length of an observation signal cut out for analyzing the spectrum of the observation signal used for estimation calculation of the noise spectrum is set longer than the signal length of an observation signal cut out for analyzing the spectrum of the observation signal as a value to be subtracted for performing subtraction with the noise spectrum.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: April 17, 2012
    Assignee: Yamaha Corporation
    Inventors: Michiko Kazama, Mikio Tohyama, Koji Kushida
  • Patent number: 7974424
    Abstract: A speaker array system for outputting, with a simplified construction, sounds audible with a nearly uniform sound volume within an arbitrarily set area. The speaker array system includes a speaker array having speaker units, a delay unit for supplying the speaker units with delayed audio signals generated by adding delays to an input audio signal, an input unit for inputting area information representing a target area to which an acoustic service is provided using an acoustic beam emitted from the speaker array and which has a normal line extending in a direction different from a normal direction of a speaker surface of the speaker array, and a control unit for calculating delays to be applied to the delay unit. Based on the delays, acoustic waves output from adjacent ones of the speaker units toward the target area are made coincident with each other and an envelope is more distorted from a spherical surface so as to face the target area as the envelope propagates closer to the target area.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: July 5, 2011
    Assignee: Yamaha Corporation
    Inventors: Koji Kushida, Takashi Yamakawa
  • Publication number: 20110064228
    Abstract: Calculation is performed for sound paths 112-1, 114-1 along which sounds emitted from a sound emitting point 104 in an acoustic space 102 are reflected and delivered to a sound receiving point 106. By the calculation, entering angles eR1, eR2 by which the sound paths enter the front side 106a of the sound receiving point 106 are obtained. Calculation is then performed to obtain angles by which respective speakers 52C, 52L, 52R, 52SR, 52SL of a 5.1 surround system are arranged in a listening room, with the front side 106a of the sound receiving point 106 centered thereon. Audio signals on the respective sound paths are distributed among channels for any two speakers. Consequently, sharp localization of sound images is achieved, requiring less calculation in simulating acoustic characteristics of the acoustic space 102 in which the sound emitting point 104 for emitting sounds and the sound receiving point 106 for receiving the sounds are placed.
    Type: Application
    Filed: November 22, 2010
    Publication date: March 17, 2011
    Applicant: Yamaha Corporation
    Inventors: Toru KITAYAMA, Kenichi Tamiya, Koji Kushida
  • Patent number: 7859533
    Abstract: Calculation is performed for sound paths 112-1, 114-1 along which sounds emitted from a sound emitting point 104 in an acoustic space 102 are reflected and delivered to a sound receiving point 106. By the calculation, entering angles ?R1, ?R2 by which the sound paths enter the front side 106a of the sound receiving point 106 are obtained. Calculation is then performed to obtain angles by which respective speakers 52C, 52L, 52R, 52SR, 52SL of a 5.1 surround system are arranged in a listening room, with the front side 106a of the sound receiving point 106 centered thereon. Audio signals on the respective sound paths are distributed among channels for any two speakers. Consequently, sharp localization of sound images is achieved, requiring less calculation in simulating acoustic characteristics of the acoustic space 102 in which the sound emitting point 104 for emitting sounds and the sound receiving point 106 for receiving the sounds are placed.
    Type: Grant
    Filed: April 4, 2006
    Date of Patent: December 28, 2010
    Assignee: Yamaha Corporation
    Inventors: Toru Kitayama, Kenichi Tamiya, Koji Kushida, Masao Kondou
  • Publication number: 20100189279
    Abstract: A microphone array signal processing apparatus which is capable of picking up sound in a low frequency band even with a compact microphone array. The microphone array signal processing apparatus is comprised of delay devices (411-1 to 411-M) that add delays to the respective ones of a plurality of sound signals output from the respective ones of a plurality of microphones constituting the microphone array, an adder (412) that sums the plurality of sound signals with the respective delays added thereto, a harmonic structure detecting section (421) that detects a harmonic structure of sound included in the sound signal, and a filtering processing section (422) that selectively passes predetermined frequency components based upon the detected harmonic structure.
    Type: Application
    Filed: April 2, 2010
    Publication date: July 29, 2010
    Applicant: YAMAHA CORPORATION
    Inventor: Koji KUSHIDA
  • Patent number: 7751574
    Abstract: In a reverberation apparatus, a storage section stores a directional characteristic representing a directivity of generated sound at a sound generating point. A position determining section determines a position of the sound generating point within an acoustic space on the basis of an instruction from the user. An orientation determining section determines an orientation of the sound generating point based on the determined position thereof. An impulse response determining section determines an impulse response for each of sound ray paths along which the sound emitted from the sound generating point travels to reach a sound receiving point, in accordance with the directional characteristic of the generated sound and the orientation of the sound generating point. A calculation section performs a convolution operation between the impulse response and an input audio signal so as to apply thereto the acoustic effect.
    Type: Grant
    Filed: March 23, 2004
    Date of Patent: July 6, 2010
    Assignee: Yamaha Corporation
    Inventor: Koji Kushida
  • Publication number: 20100111311
    Abstract: A delay time calculation apparatus enabling all the speaker units of a delay array type speaker array to contribute to formation of a combined wavefront. Sound receiving points for acoustic waves output from the speaker units are set within a target area for the acoustic waves. For each speaker unit, an average value of differences between distances between the sound receiving points for the speaker units and other speaker units and distances between the sound receiving points for the speaker units and the speaker units is determined, and an average value of differences between distances from the other speaker units to sound receiving points for the other speaker units and distances from the speaker units to the sound receiving points for the other speaker units is determined. An average of the average values is converted into a delay time, thereby determining the delay time for each speaker unit.
    Type: Application
    Filed: November 4, 2009
    Publication date: May 6, 2010
    Applicant: YAMAHA CORPORATION
    Inventors: Takashi YAMAKAWA, Koji KUSHIDA
  • Publication number: 20090290717
    Abstract: A delay time calculation apparatus that enables all of speaker units constituting a speaker array to contribute to the formation of a combined wavefront directed to an area specified by a user. The delay time calculation apparatus includes a delay time calculation unit that calculates delay times of delayed audio signals supplied to the speaker units such that a ratio at which an evaluation object area is occupied by an area to which an acoustic wave output from each speaker unit reaches earlier than acoustic waves output from the other speaker units falls within a predetermined range. The evaluation object area is a target area to which a combined wavefront of acoustic waves output from the speaker units is directed, or is a perspective projection image of the target area onto a predetermined evaluation plane.
    Type: Application
    Filed: May 18, 2009
    Publication date: November 26, 2009
    Applicant: YAMAHA CORPORATION
    Inventors: Koji KUSHIDA, Takashi YAMAKAWA
  • Publication number: 20090110219
    Abstract: A speaker array system for outputting, with a simplified construction, sounds audible with a nearly uniform sound volume within an arbitrarily set area. The speaker array system includes a speaker array having speaker units, a delay unit for supplying the speaker units with delayed audio signals generated by adding delays to an input audio signal, an input unit for inputting area information representing a target area to which an acoustic service is provided using an acoustic beam emitted from the speaker array and which has a normal line extending in a direction different from a normal direction of a speaker surface of the speaker array, and a control unit for calculating delays to be applied to the delay unit. Based on the delays, acoustic waves output from adjacent ones of the speaker units toward the target area are made coincident with each other and an envelope is more distorted from a spherical surface so as to face the target area as the envelope propagates closer to the target area.
    Type: Application
    Filed: October 31, 2008
    Publication date: April 30, 2009
    Applicant: YAMAHA CORPORATION
    Inventors: Koji KUSHIDA, Takashi YAMAKAWA
  • Publication number: 20090003634
    Abstract: A speaker array apparatus capable of carrying out directivity control over a wide frequency range with reduced processing load. In the speaker array apparatus, an audio signal input from a signal input unit is divided into components by a signal divider unit to generate divided audio signals of different frequency ranges. The divided audio signals are amplified by amplifier units of a signal processing unit with gains set in accordance with window functions set to the amplifier units, and a sound emission unit emits sounds based on the amplified audio signals, whereby desired directional characteristics can be attained over a wide frequency range and an amount of calculation in the processing by the signal processing unit can be reduced.
    Type: Application
    Filed: June 25, 2008
    Publication date: January 1, 2009
    Applicant: YAMAHA CORPORATION
    Inventor: Koji Kushida
  • Patent number: 7463740
    Abstract: A data processing apparatus is designed for simulating an acoustic characteristic of an acoustic space which contains a sound source for generating a sound and a sound receiving point for receiving the sound. In the apparatus, each of a plurality of characteristic control sections processes sound data and outputs the processed sound data. The characteristic control sections correspond to transmission paths which must exist in the acoustic space such that the sound generated from the sound source travels to the sound receiving point through the respective transmission paths. An instruction section provides a processing instruction of the sound data to each characteristic control section such that each characteristic control section processes the sound data according to the provided processing instruction to thereby execute the simulation of the sound traveling through the corresponding transmission path.
    Type: Grant
    Filed: January 6, 2004
    Date of Patent: December 9, 2008
    Assignee: Yamaha Corporation
    Inventor: Koji Kushida
  • Publication number: 20080226093
    Abstract: A speaker array apparatus capable of performing control to narrow the directivity angle of low-frequency range sounds, without causing a speaker array to be large in size. An audio signal input to the speaker array apparatus is divided into an audio signal in which low-frequency range components of the input audio signal are included and an audio signal in which low-frequency range components thereof are attenuated, and the former audio signal is signal-processed by a directivity controller. Based on the processed audio signal, sounds are emitted from speakers disposed at four corners of the speaker array, whereby the directivity angle of acoustic beam in low-frequency range can be made narrower than when sounds are emitted from all the speakers of the speaker array.
    Type: Application
    Filed: March 7, 2008
    Publication date: September 18, 2008
    Applicant: YAMAHA CORPORATION
    Inventors: Koji KUSHIDA, Kenichi TAMIYA, Takashi YAMAKAWA, Takao NAKAYA, Ken IWAYAMA
  • Publication number: 20080199017
    Abstract: A speaker array apparatus capable of performing directivity control with ease even when sound emission is performed based on audio signals of different frequency ranges. The speaker array apparatus includes a speaker unit for emitting high-frequency range sound, and another speaker unit for emitting low- and high-frequency range sound. A signal processed by a high pass filter is used for generation of both audio signals used by these speaker units to emit the high-frequency range sounds. Since both the audio signals are rotated in phase similarly to each other, the phases of audio signals supplied to both the speaker units are in coincidence with each other in high-frequency range, which makes it easy to carry out directivity control.
    Type: Application
    Filed: February 20, 2008
    Publication date: August 21, 2008
    Applicant: YAMAHA CORPORATION
    Inventors: Takashi YAMAKAWA, Kenichi TAMIYA, Koji KUSHIDA, Ken IWAYAMA
  • Publication number: 20060251260
    Abstract: Calculation is performed for sound paths 112-1, 114-1 along which sounds emitted from a sound emitting point 104 in an acoustic space 102 are reflected and delivered to a sound receiving point 106. By the calculation, entering angles ?R1, ?R2 by which the sound paths enter the front side 106a of the sound receiving point 106 are obtained. Calculation is then performed to obtain angles by which respective speakers 52C, 52L, 52R, 52SR, 52SL of a 5.1 surround system are arranged in a listening room, with the front side 106a of the sound receiving point 106 centered thereon. Audio signals on the respective sound paths are distributed among channels for any two speakers. Consequently, sharp localization of sound images is achieved, requiring less calculation in simulating acoustic characteristics of the acoustic space 102 in which the sound emitting point 104 for emitting sounds and the sound receiving point 106 for receiving the sounds are placed.
    Type: Application
    Filed: April 4, 2006
    Publication date: November 9, 2006
    Applicant: Yamaha Corporation
    Inventors: Toru Kitayama, Kenichi Tamiya, Koji Kushida, Masao Kondou
  • Publication number: 20060198536
    Abstract: A microphone array signal processing apparatus which is capable of picking up sound in a low frequency band even with a compact microphone array. The microphone array signal processing apparatus is comprised of delay devices (411-1 to 411-M) that add delays to the respective ones of a plurality of sound signals output from the respective ones of a plurality of microphones constituting the microphone array, an adder (412) that sums the plurality of sound signals with the respective delays added thereto, a harmonic structure detecting section (421) that detects a harmonic structure of sound included in the sound signal, and a filtering processing section (422) that selectively passes predetermined frequency components based upon the detected harmonic structure.
    Type: Application
    Filed: March 3, 2006
    Publication date: September 7, 2006
    Applicant: Yamaha Corporation
    Inventor: Koji Kushida