JP2011123389A5

JP2011123389A5 -

Info

Publication number: JP2011123389A5
Application number: JP2009282497A
Authority: JP
Filing date: 2009-12-14
Publication date: 2012-12-27

Description

上記の目的を達成するために、本発明の騒音低減装置は、騒音源から発せられる騒音を検知する複数の騒音検知手段と、騒音検知手段により検知された騒音を制御空間の制御中心において打ち消すための制御音信号を生成させる騒音制御手段と、騒音制御手段からの制御音信号に基づいて制御音を出力する制御音出力手段と、制御中心において騒音源から発せられる騒音と制御音出力手段から出力される制御音とを重畳して誤差音を検知する誤差音検知手段と、を備えた騒音低減装置であって、複数の騒音検知手段を制御空間またはその近傍に配置し、騒音制御手段は、複数の騒音検知手段の出力を入力とする適応デジタルフィルタと、複数の騒音検知手段の出力および誤差音検知手段の出力を入力とし、誤差音を最小にするように適応デジタルフィルタのフィルタ係数を更新するフィルタ係数算出部と、複数の騒音検知手段に対応する適応デジタルフィルタからの複数の出力を加算して制御音信号を生成する加算手段と、を備え、騒音制御手段は複数の騒音検知手段のそれぞれに対して制御空間内の特定の位置と騒音検知手段との距離に係わる制御係数で騒音検知手段の検出値の重み付けを行い、制御音の出力を制御することを特徴とする。 In order to achieve the above object, a noise reduction device according to the present invention includes a plurality of noise detection means for detecting noise emitted from a noise source, and canceling noise detected by the noise detection means at the control center of the control space. Noise control means for generating a control sound signal, control sound output means for outputting a control sound based on the control sound signal from the noise control means, noise emitted from a noise source at the control center, and output from the control sound output means An error sound detection means for detecting an error sound by superimposing a control sound, wherein a plurality of noise detection means are arranged in a control space or in the vicinity thereof, and the noise control means comprises: An adaptive digital filter that receives the outputs of a plurality of noise detection means and an output of the plurality of noise detection means and the output of the error sound detection means as inputs, and an adaptive digital filter that minimizes the error sound. A filter coefficient calculation unit that updates a filter coefficient of the filter, and an addition unit that generates a control sound signal by adding a plurality of outputs from an adaptive digital filter corresponding to the plurality of noise detection units, and the noise control unit includes: It performs weighting of the detected value of the noise detection means in the control factor according to the distance between the specific position and the noise detection means of the control space for each of a plurality of noise detection means, to control the output of the braking Gooto Features.

また本発明の騒音低減装置では、制御係数は制御空間内の特定の位置と騒音検知手段との距離が小さいほど小さく、距離が大きいほど大きくてもよい。このような構成により、エコーに最も大きく影響する騒音検知手段の検出結果の騒音制御への寄与度を少なくできるので、利用者から発せられる音声に起因するエコーの発生を効率的に抑制することが可能となる。 In the noise reduction device of the present invention, the control factor as the distance between the specific position and the noise detection means in the control space is small small distance may be large active larger. With such a configuration, it is possible to reduce the contribution to the noise control of the detection result of the noise detection means that has the greatest influence on the echo, so that it is possible to efficiently suppress the occurrence of the echo due to the voice emitted from the user. It becomes possible.

Claims

A plurality of noise detection means for detecting noise emitted from a noise source;
Noise control means for generating a control sound signal for canceling the noise detected by the noise detection means at the control center of the control space;
Control sound output means for outputting a control sound based on a control sound signal from the noise control means;
A noise reduction device comprising: error sound detection means for detecting error sound by superimposing noise emitted from the noise source at the control center and control sound output from the control sound output means,
The plurality of noise detection means are arranged in the control space or in the vicinity thereof,
The noise control means receives the output of the plurality of noise detection means as an input, the output of the plurality of noise detection means and the output of the error sound detection means as inputs, and minimizes the error sound. A filter coefficient calculation unit for updating the filter coefficient of the adaptive digital filter,
Adding means for adding the plurality of outputs from the adaptive digital filter corresponding to the plurality of noise detection means to generate the control sound signal,
The noise control unit performs the weighting of the detected value of the noise detection means in the control factor according to the distance between the specific position and the noise detection unit of the control space with respect to each of the plurality of noise detection means, before A noise reduction device for controlling the output of the control sound.

2. The noise reduction apparatus according to claim 1, wherein the control coefficient is a coefficient relating to a distance between a specific position at or near the control center and the noise detection means.

The control factor as the small distance between the specific position and the noise detection unit of the control space small, the noise reducing device according to claim 1 or claim 2, characterized in that the greater the distance is large have size .

The amplifier according to claim 1, further comprising an amplifier that amplifies the outputs of the plurality of noise detection units and outputs the amplified outputs to the filter coefficient calculation unit, wherein the control coefficient is an amplification factor of the amplifier. The noise reduction device according to any one of claims.

When the maximum value of the “absolute value” of each filter coefficient of the adaptive digital filter corresponding to the plurality of noise detection means is input, and the maximum value of the filter coefficient exceeds the threshold value compared with a preset threshold value 4 further includes a threshold value determination unit that controls to stop updating the filter coefficient of the corresponding adaptive digital filter, and the control coefficient is the threshold value. The noise reduction device according to item.

When the filter coefficient of the adaptive digital filter is fixed, the digital filter further includes an amplifier that amplifies the output of each of the plurality of noise detection means and outputs the amplified output to the adaptive digital filter. The noise reduction device according to any one of claims 1 to 3, wherein the noise reduction device is provided.

The noise reduction device according to any one of claims 1 to 6, wherein the control coefficient includes a correction value related to an installation condition of the noise detection means.