公开(公告)号：US10854187B2

公开(公告)日：2020-12-01

申请号：US16508624

申请日：2019-07-11

Applicant: ALPINE ELECTRONICS, INC. ,  A School Corporation Kansai University

Inventor： Ryosuke Tachi ,  Yoshinobu Kajikawa

IPC: G10K11/00 ,  G10K11/178

Abstract: Audio (noise source) is output as a cancellation sound through a variable filter and a first filter, and transmitted to the second filter. A subtractor subtracts an output of a second filter from an output of a microphone, and an adaptive algorithm execution unit updates a transfer function of the variable filter so that the subtracted result becomes zero (0). A transfer function A for the first filter is a transfer function which can cancel noise at a position of a user's ear by setting, as the cancellation sound, a sound obtained by applying the transfer function A to audio at the time of learning, and a transfer function B for the second filter is a transfer function which can eliminate, for the cancellation sound, a difference between a sound obtained by applying the transfer function B to audio and the output of the microphone.

公开(公告)号：US20200372893A1

公开(公告)日：2020-11-26

申请号：US16880170

申请日：2020-05-21

Applicant: ALPINE ELECTRONICS, INC.

Inventor： Ryosuke Tachi

IPC: G10K11/178 ,  H04R1/10

Abstract: A first cancellation signal output from a first speaker cancels noise at a first cancellation point, which is a typical position of the right ear of a user, together with a second cancellation signal output from a second speaker. In addition, the second cancellation signal output from the second speaker cancels noise at a second cancellation point, which is a typical position of the left ear of the user, together with the first cancellation signal output from the first speaker. The first speaker and the second speaker are arranged side by side on a second line segment, which passes through the midpoint of a first line segment connecting the first cancellation point and the second cancellation point to each other and is perpendicular to the first line segment, and a range where the relationship between noise and the first cancellation signal and the second cancellation signal is the same as that at the cancellation point is extended.

公开(公告)号：US20200372892A1

公开(公告)日：2020-11-26

申请号：US16880145

申请日：2020-05-21

Applicant: ALPINE ELECTRONICS, INC.

Inventor： Ryosuke Tachi ,  Yoshinobu Kajikawa

IPC: G10K11/178

Abstract: Adaptive filters output a cancellation sound from a speaker, a selector selects outputs of a plurality of auxiliary filters each corresponding to different positions, a subtractor subtracts the selected output from the output of the microphone and outputs the subtracted output to the adaptive filter as an error signal, and a position detection device detects a position of a head of a user. A transfer function estimated so that the error signal becomes 0 when noise is canceled at the corresponding position is preset in the auxiliary filter. When the auxiliary filter corresponding to the position close to the head of the user changes, the switching control unit stepwise increases the frequency with which the output of the auxiliary filter is selected by the selector to 100%.

公开(公告)号：US10109295B2

公开(公告)日：2018-10-23

申请号：US15468572

申请日：2017-03-24

Applicant: Alpine Electronics, Inc.

Inventor： Ryosuke Tachi

IPC: G10L19/14 ,  G10L21/038

Abstract: An upper limit of a frequency range of audio indicated by input audio data is detected. A representative point extraction unit downsamples the input audio data to a sampling rate set to be less than or equal to twice the detected upper limit to obtain representative-point audio data. An interpolation processing unit upsamples the representative-point audio data by using a fractal interpolation function (FIF) that uses a mapping function calculated by a mapping function calculation unit, while using the input audio data, if necessary, to generate high-frequency interpolated audio data.

公开(公告)号：US11501748B2

公开(公告)日：2022-11-15

申请号：US16880170

申请日：2020-05-21

Applicant: ALPINE ELECTRONICS, INC.

Inventor： Ryosuke Tachi

IPC: G10K11/178 ,  H04R1/10

Abstract: A first cancellation signal output from a first speaker cancels noise at a first cancellation point, which is a typical position of the right ear of a user, together with a second cancellation signal output from a second speaker. In addition, the second cancellation signal output from the second speaker cancels noise at a second cancellation point, which is a typical position of the left ear of the user, together with the first cancellation signal output from the first speaker. The first speaker and the second speaker are arranged side by side on a second line segment, which passes through the midpoint of a first line segment connecting the first cancellation point and the second cancellation point to each other and is perpendicular to the first line segment, and a range where the relationship between noise and the first cancellation signal and the second cancellation signal is the same as that at the cancellation point is extended.

公开(公告)号：US11335314B2

公开(公告)日：2022-05-17

申请号：US16880145

申请日：2020-05-21

Applicant: ALPINE ELECTRONICS, INC.

Inventor： Ryosuke Tachi ,  Yoshinobu Kajikawa

IPC: G10K11/16 ,  G10K11/178

Abstract: Adaptive filters output a cancellation sound from a speaker, a selector selects outputs of a plurality of auxiliary filters each corresponding to different positions, a subtractor subtracts the selected output from the output of the microphone and outputs the subtracted output to the adaptive filter as an error signal, and a position detection device detects a position of a head of a user. A transfer function estimated so that the error signal becomes 0 when noise is canceled at the corresponding position is preset in the auxiliary filter. When the auxiliary filter corresponding to the position close to the head of the user changes, the switching control unit stepwise increases the frequency with which the output of the auxiliary filter is selected by the selector to 100%.

公开(公告)号：US11276385B2

公开(公告)日：2022-03-15

申请号：US16929486

申请日：2020-07-15

Applicant: ALPINE ELECTRONICS, INC.

Inventor： Ryosuke Tachi ,  Keita Tanno ,  Mone Isami ,  Ryo Ito ,  Haruki Uesugi

IPC: G10K11/178

Abstract: With respect to a noise reduction device using a speaker and a microphone corresponding to each seat in a vehicle to reduce a noise in each seat, the noise reduction device includes, a signal processing unit configured to generate a canceling sound that reduces a noise at an ear of an occupant in a predetermined seat by using an auxiliary filter, an operation setting unit configured to disable operations of a speaker and a microphone corresponding to each empty seat in the vehicle, and an auxiliary filter setting unit configured to change a setting value of the auxiliary filter used by the signal processing unit to generate the canceling sound in accordance with the number of occupants in seats other than the predetermined seat, the seats affecting the noise in the predetermined seat.

公开(公告)号：US20200020315A1

公开(公告)日：2020-01-16

申请号：US16508624

申请日：2019-07-11

Applicant: ALPINE ELECTRONICS, INC. ,  A School Corporation Kansai University

Inventor： Ryosuke Tachi ,  Yoshinobu Kajikawa

IPC: G10K11/178

Abstract: Audio (noise source) is output as a cancellation sound through a variable filter and a first filter, and transmitted to the second filter. A subtractor subtracts an output of a second filter from an output of a microphone, and an adaptive algorithm execution unit updates a transfer function of the variable filter so that the subtracted result becomes zero (0). A transfer function A for the first filter is a transfer function which can cancel noise at a position of a user's ear by setting, as the cancellation sound, a sound obtained by applying the transfer function A to audio at the time of learning, and a transfer function B for the second filter is a transfer function which can eliminate, for the cancellation sound, a difference between a sound obtained by applying the transfer function B to audio and the output of the microphone.

公开(公告)号：US20170345442A1

公开(公告)日：2017-11-30

申请号：US15468572

申请日：2017-03-24

Applicant: Alpine Electronics, Inc.

Inventor： Ryosuke Tachi

IPC: G10L21/038

CPC classification number: G10L21/038 ,  G10L21/0388 ,  H03H17/028 ,  H03H17/0621

Abstract: An upper limit of a frequency range of audio indicated by input audio data is detected. A representative point extraction unit downsamples the input audio data to a sampling rate set to be less than or equal to twice the detected upper limit to obtain representative-point audio data. An interpolation processing unit upsamples the representative-point audio data by using a fractal interpolation function (FIF) that uses a mapping function calculated by a mapping function calculation unit, while using the input audio data, if necessary, to generate high-frequency interpolated audio data.

公开(公告)号：US11043202B2

公开(公告)日：2021-06-22

申请号：US16724846

申请日：2019-12-23

Applicant: ALPINE ELECTRONICS, INC.

Inventor： Ryosuke Tachi ,  Yoshinobu Kajikawa

IPC: G10K11/178

Abstract: Two subsystems, each including a microphone, a speaker, a canceling sound-generating adder, an error-computing adder, and two adaptive filters and two auxiliary filters that accept two noises as input, are provided in correspondence with two cancellation positions. Each canceling sound-generating adder adds together the outputs from the adaptive filters and outputs the result to the speaker of each subsystem. Each error-computing adder adds together the output from the microphone of the subsystem and the output from the auxiliary filter of the subsystem, and the result is treated as the error of the adaptive filters of each subsystem. A transfer function is learned in advance and set in each auxiliary filter such that each error computed by each error-computing adder becomes zero (0) when a transfer function in which each noise is canceled at each cancellation position in a predetermined standard acoustic environment is set in each adaptive filter.