JPH0828635B2 - Noise resistant adaptive equalizer - Google Patents
Noise resistant adaptive equalizerInfo
- Publication number
- JPH0828635B2 JPH0828635B2 JP15688790A JP15688790A JPH0828635B2 JP H0828635 B2 JPH0828635 B2 JP H0828635B2 JP 15688790 A JP15688790 A JP 15688790A JP 15688790 A JP15688790 A JP 15688790A JP H0828635 B2 JPH0828635 B2 JP H0828635B2
- Authority
- JP
- Japan
- Prior art keywords
- adaptive filter
- output
- noise
- coefficient
- filter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Control Of Amplification And Gain Control (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Circuit For Audible Band Transducer (AREA)
- Filters That Use Time-Delay Elements (AREA)
- Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 本発明は騒音環境下における耐騒音適応イコライザに
関するものである。TECHNICAL FIELD The present invention relates to a noise resistant adaptive equalizer in a noisy environment.
従来の技術 近年、適応フィルタなどのディジタル信号処理技術を
用いてスピーカを含めた音響特性を補正する方法が提案
されている。2. Description of the Related Art In recent years, a method of correcting acoustic characteristics including a speaker using a digital signal processing technique such as an adaptive filter has been proposed.
従来、この種の適応イコライザは特開平1-240099号に
示すような構成が一般的であった。以下、その構成につ
いて第４図を参照しながら説明する。第４図に示すよう
に、音響信号入力端子１に入力された音響信号は適応フ
ィルタ33により補正されてスピーカ10より放射され、マ
イクロフォン９により受音された信号は、入力信号にあ
らかじめ遅延器31を介して特性設定部32により設定され
た信号と加算器34で比較されその信号が小さくなるよう
に係数制御器６を介して常に適応フィルタ33が制御され
ることになる。Heretofore, this type of adaptive equalizer has generally been configured as shown in Japanese Patent Laid-Open No. 1-240099. The configuration will be described below with reference to FIG. As shown in FIG. 4, the acoustic signal input to the acoustic signal input terminal 1 is corrected by the adaptive filter 33 and radiated from the speaker 10, and the signal received by the microphone 9 is input to the delay device 31 in advance. The signal set by the characteristic setting unit 32 via the above is compared with the adder 34, and the adaptive filter 33 is always controlled via the coefficient controller 6 so that the signal becomes smaller.
発明が解決しようとする課題 しかしながら、上記従来の構成では、適応フィルタ33
の動作中に外部からの騒音がマイクロフォン９に入った
場合、適応処理に誤動作が生じ収束に長い時間を必要と
したり、収束不可能にもなり得るという問題があった。However, in the above conventional configuration, the adaptive filter 33 is used.
If a noise from the outside enters the microphone 9 during the operation of 1, there is a problem that a malfunction occurs in the adaptive processing, a long time is required for the convergence, or the convergence becomes impossible.
本発明は上記従来の問題を解決するもので、騒音環境
下においても適応処理を正確に行うことができる耐騒音
適応イコライザを提供することを目的とするものであ
る。The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a noise-resistant adaptive equalizer that can accurately perform adaptive processing even in a noisy environment.
課題を解決するための手段 上記課題を解決するために本発明の耐騒音適応イコラ
イザは、騒音源の近傍に設置した騒音検出器と、前記騒
音検出器の出力を受ける第１の適応フィルタと、音響信
号入力端子に接続された第２の適応フィルタと、前記音
響信号入力端子に接続された所望特性のイコライザと、
前記第２の適応フィルタに縦続接続されたスピーカと、
前記スピーカからの受音点に設置したマイクロフォンと
前記マイクロホンの出力から前記イコライザの出力を減
算する第１の減算器と、前記第１の減算器の出力から前
記第１の適応フィルタの出力を減算する第２の減算器
と、前記第２の減算器の出力を誤差入力とするフィルタ
係数制御器と、前記音響信号入力端子に入力される音響
入力信号かあるいは前記騒音検出器の信号かのどちらか
一方を選択してフィルタ係数制御器の基準入力に入力す
る第１の選択手段と、前記フィルタ係数制御器の係数出
力を前記第１の適応フィルタの係数メモリかあるいは前
記第２の適応フィルタの係数メモリかのどちらか一方を
選択して入力する第２の選択手段とを備え、最初に前記
第１の選択手段を前記騒音検出器の信号に選択し、かつ
前記第２の選択手段を前記第１の適応フィルタの係数メ
モリに選択して前記フィルタ係数制御器を動作させ、次
に前記第１の選択手段を前記音響入力信号に選択し、か
つ前記第２の選択手段を前記第２の適応フィルタの係数
メモリに選択して前記フィルタ係数制御器を動作させる
構成としたものである。Means for Solving the Problems In order to solve the above problems, a noise resistant adaptive equalizer of the present invention is a noise detector installed in the vicinity of a noise source, and a first adaptive filter that receives the output of the noise detector, A second adaptive filter connected to the acoustic signal input terminal, an equalizer having a desired characteristic connected to the acoustic signal input terminal,
A speaker cascade-connected to the second adaptive filter;
A microphone installed at a sound receiving point from the speaker, a first subtractor that subtracts the output of the equalizer from the output of the microphone, and a output of the first adaptive filter from the output of the first subtractor A second subtractor, a filter coefficient controller using the output of the second subtractor as an error input, and an acoustic input signal input to the acoustic signal input terminal or a signal of the noise detector. First selecting means for selecting one of them and inputting it to the reference input of the filter coefficient controller, and a coefficient output of the filter coefficient controller for the coefficient memory of the first adaptive filter or for the second adaptive filter. Second selecting means for selecting and inputting one of the coefficient memories, first selecting the first selecting means for the signal of the noise detector, and the second selecting means. Select the coefficient memory of the first adaptive filter to operate the filter coefficient controller, then select the first selection means for the acoustic input signal, and the second selection means for the second selection means. The adaptive filter coefficient memory is selected to operate the filter coefficient controller.
作用 上記構成により、受聴位置のマイクロフォンに入って
きた騒音信号を騒音検出器により検出し、騒音信号に適
応フィルタ処理をほどこした信号で打ち消した状態にし
たのち、音響特性補正の適応イコライザを動作させるの
で騒音に拘わらず正確な適応動作が可能となる。Action With the above configuration, the noise signal that has entered the microphone at the listening position is detected by the noise detector, and the noise signal is canceled by the signal that has undergone adaptive filtering, and then the adaptive equalizer for acoustic characteristic correction is operated. Therefore, accurate adaptive operation is possible regardless of noise.
実施例 以下、本発明の実施例について図面を参照しながら説
明する。Examples Hereinafter, examples of the present invention will be described with reference to the drawings.
第１図は本発明の一実施例を示す耐騒音適応イコライ
ザの構成図である。本実施例は騒音環境下においても音
響補正イコライザの適応処理を正確に行うことを目的と
している。第１図に示すように、２は騒音源12の近傍に
設置した騒音検出器、７は騒音源12の出力を受ける適応
フィルタ、11は音響信号入力端子１に接続された適応フ
ィルタ、３は音響信号入力端子１に接続され、所望特性
を設定したイコライザ、10は適応フィルタ11に縦続接続
されたスピーカ、９はスピーカ10からの受音点に設置し
たマイクロフォン、13はマイクロフォン９の出力からイ
コライザ３の出力を減算する減算器、８は減算器13の出
力から適応フィルタ７の出力を減算する減算器、６は減
算器８の出力を誤差入力とするフィルタ係数制御器、４
は音響信号入力端子１に入力される音響入力信号と騒音
検出器２の信号出力とを切換えて係数制御器６に接続す
る第１の選択手段、５は係数制御器６の出力を適応フィ
ルタ７と適応フィルタ11に切換える第２の選択手段であ
る。FIG. 1 is a block diagram of a noise resistant adaptive equalizer showing an embodiment of the present invention. The purpose of this embodiment is to accurately perform the adaptive processing of the acoustic correction equalizer even in a noisy environment. As shown in FIG. 1, 2 is a noise detector installed near the noise source 12, 7 is an adaptive filter that receives the output of the noise source 12, 11 is an adaptive filter connected to the acoustic signal input terminal 1, and 3 is An equalizer connected to the acoustic signal input terminal 1 and having desired characteristics set, 10 a speaker cascade-connected to the adaptive filter 11, 9 a microphone installed at a sound receiving point from the speaker 10, 13 an equalizer from the output of the microphone 9. 3 is a subtractor for subtracting the output of the subtractor 13, 8 is a subtractor for subtracting the output of the adaptive filter 7 from the output of the subtractor 13, 6 is a filter coefficient controller which uses the output of the subtractor 8 as an error input, 4
Is a first selecting means for switching between the acoustic input signal input to the acoustic signal input terminal 1 and the signal output of the noise detector 2 and connecting it to the coefficient controller 6, and 5 is an adaptive filter 7 for the output of the coefficient controller 6. And a second selection means for switching to the adaptive filter 11.
上記構成において以下、その動作を説明する。最初は
音響信号を入力せずに騒音源12の影響を取り除く処理を
行う。すなわち、選択手段４および５はＡ側に選択す
る。このときの等価構成図を第２図に示す。第２図にお
いて、騒音検出器２の検出信号は適応フィルタ７に入力
され、受聴位置に設置されたマイクロフォン９で受音さ
れた騒音信号と減算器８により減算され、係数制御器６
に誤差信号として入力される。係数制御器６はこの誤差
信号が小さくなるように学習同定法（「ディジタル信号
処理の応用」p219コロナ社 電気通信学会）などのアル
ゴリズムを用いてフィルタ係数を計算し、適応フィルタ
７の係数メモリに書き込む。つまり適応フィルタ７を騒
音源12からマイクロフォン９までの音響伝送特性に同定
させることになり、減算器８の出力は騒音源の信号の影
響を除くことができる。The operation of the above configuration will be described below. Initially, processing for removing the influence of the noise source 12 is performed without inputting an acoustic signal. That is, the selecting means 4 and 5 select to the A side. An equivalent configuration diagram at this time is shown in FIG. In FIG. 2, the detection signal of the noise detector 2 is input to the adaptive filter 7, subtracted by the subtractor 8 from the noise signal received by the microphone 9 installed at the listening position, and the coefficient controller 6
Is input as an error signal. The coefficient controller 6 calculates a filter coefficient using an algorithm such as a learning identification method (“Application of Digital Signal Processing” p219 Corona Electronics Institute of Telecommunications) so that this error signal becomes small, and stores it in the coefficient memory of the adaptive filter 7. Write. That is, the adaptive filter 7 is identified by the acoustic transmission characteristics from the noise source 12 to the microphone 9, and the output of the subtractor 8 can remove the influence of the signal of the noise source.
次に、選択手段４および５をＢ側に選択し、音響信号
を入力端子１に入力する。このときの等価構成図を第３
図に示す。第３図において、入力信号は適応フィルタ11
を通ってスピーカ10より放射され、音響伝送系を経て受
聴位置のマイクロフォン９で受音される。一方、音響信
号入力端子１に入力された音響信号は所望の特性を与え
たイコライザ３を通して減算器13でマイクロフォン９の
受音信号と減算され、さらに減算器８によって騒音信号
が取り除かれた後、誤差信号として係数制御器６に入力
される。係数制御器６はこの誤差信号が小さくなるよう
な係数を同様に計算して適応フィルタ11の係数メモリに
書き込む。Next, the selecting means 4 and 5 are selected to the B side, and the acoustic signal is input to the input terminal 1. The equivalent configuration diagram at this time is
Shown in the figure. In FIG. 3, the input signal is the adaptive filter 11
The sound is radiated from the speaker 10 through the sound transmission system and is received by the microphone 9 at the listening position through the acoustic transmission system. On the other hand, the acoustic signal input to the acoustic signal input terminal 1 is subtracted from the sound reception signal of the microphone 9 by the subtractor 13 through the equalizer 3 that gives a desired characteristic, and further, after the noise signal is removed by the subtractor 8, It is input to the coefficient controller 6 as an error signal. The coefficient controller 6 similarly calculates a coefficient with which the error signal becomes small and writes it in the coefficient memory of the adaptive filter 11.
このように、適応処理を行うことにより、適応フィル
タ11の係数はスピーカを含めた音響伝送系をイコライザ
に設定した所望の特性に近似するように収束する。In this way, by performing the adaptive processing, the coefficient of the adaptive filter 11 converges so as to approximate the desired characteristics in which the acoustic transmission system including the speaker is set as the equalizer.
このように本発明の実施例によれば、騒音下において
もその影響を取り除くことができる。また、係数制御器
の動作およびアルゴリズムは騒音伝送系を同定する場合
とイコライザを適応させる場合とに共通に用いることに
より、演算量の多い係数制御器を切り替えて使うことが
できるので、全体としてのハードウェアが軽減される。As described above, according to the embodiment of the present invention, it is possible to eliminate the influence thereof even in the presence of noise. In addition, since the operation and algorithm of the coefficient controller are commonly used for identifying the noise transmission system and for adapting the equalizer, the coefficient controller with a large amount of calculation can be switched and used. Hardware is reduced.
発明の効果 以上のように本発明によれば、騒音検出器により検出
した信号に適応フィルタ処理をほどこし、騒音信号を打
ち消した状態にしたのち、音響特性補正の適応イコライ
ザを動作させるので、騒音環境下においても音響補正イ
コライザの適応処理を正確に行うことができるものであ
る。As described above, according to the present invention, the signal detected by the noise detector is subjected to the adaptive filter processing to cancel the noise signal, and then the adaptive equalizer for correcting the acoustic characteristic is operated. Even below, the adaptive processing of the acoustic correction equalizer can be accurately performed.
第１図は本発明の一実施例を示す耐騒音適応イコライザ
の構成図、第２図は同耐騒音適応イコライザの選択手段
がＡ側の場合の等価構成図、第３図は同耐騒音適応イコ
ライザの選択手段がＢ側の場合の等価構成図、第４図は
従来の耐騒音適応イコライザの構成図である。 １…音響信号入力端子、２…騒音検出器、３…イコライ
ザ、4,5…選択手段、６…係数制御器、7,11…適応フィ
ルタ、8,13…減算器、９…マイクロフォン、10…スピー
カ。FIG. 1 is a configuration diagram of a noise resistant adaptive equalizer showing an embodiment of the present invention, FIG. 2 is an equivalent configuration diagram when the selecting means of the noise resistant adaptive equalizer is on the A side, and FIG. 3 is the same noise resistant adaptive. FIG. 4 is an equivalent configuration diagram when the equalizer selection means is on the B side, and FIG. 4 is a configuration diagram of a conventional noise-resistant adaptive equalizer. 1 ... Acoustic signal input terminal, 2 ... Noise detector, 3 ... Equalizer, 4,5 ... Selection means, 6 ... Coefficient controller, 7,11 ... Adaptive filter, 8,13 ... Subtractor, 9 ... Microphone, 10 ... Speaker.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 鈴木 知和 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (72)発明者 鈴木 良二 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomokazu 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Ryoji Suzuki, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.
Claims (1)
記騒音検出器の出力を受ける第１の適応フィルタと、音
響信号入力端子に接続された第２の適応フィルタと、前
記音響信号入力端子に接続された所望特性のイコライザ
と、前記第２の適応フィルタに縦続接続されたスピーカ
と、前記スピーカからの受音点に設置したマイクロフォ
ンと、前記マイクロフォンの出力から前記イコライザの
出力を減算する第１の減算器と、前記第１の減算器の出
力から前記第１の適応フィルタの出力を減算する第２の
減算器と、前記第２の減算器の出力を誤差入力とするフ
ィルタ係数制御器と、前記音響入力端子に入力される音
響入力信号かあるいは前記騒音検出器の信号かのどちら
か一方を選択してフィルタ係数制御器の基準入力に入力
する第１の選択手段と、前記フィルタ係数制御器の係数
出力を前記第１の適応フィルタの係数メモリかあるいは
前記第２の適応フィルタの係数メモリかのどちらか一方
を選択して入力する第２の選択手段とを備え、最初に前
記第１の選択手段を前記騒音検出器の信号に選択し、か
つ前記第２の選択手段を前記第１の適応フィルタの係数
メモリに選択して前記フィルタ係数制御器を動作させ、
次に前記第１の選択手段を前記音響入力信号に選択し、
かつ前記第２の選択手段を前記第２の適応フィルタの係
数メモリに選択して前記フィルタ係数制御器を動作させ
る構成とした耐騒音適応イコライザ。1. A noise detector installed near a noise source, a first adaptive filter for receiving the output of the noise detector, a second adaptive filter connected to an acoustic signal input terminal, and the acoustic signal. An equalizer having a desired characteristic connected to an input terminal, a speaker cascade-connected to the second adaptive filter, a microphone installed at a sound receiving point from the speaker, and an output of the equalizer subtracted from an output of the microphone. A first subtractor, a second subtractor that subtracts the output of the first adaptive filter from the output of the first subtractor, and a filter coefficient that uses the output of the second subtractor as an error input. A first selector for selecting either the controller or the sound input signal input to the sound input terminal or the signal of the noise detector and inputting it to the reference input of the filter coefficient controller. And second selecting means for selecting and inputting either the coefficient memory of the first adaptive filter or the coefficient memory of the second adaptive filter to the coefficient output of the filter coefficient controller. , First selecting the first selecting means for the signal of the noise detector, and selecting the second selecting means for the coefficient memory of the first adaptive filter to operate the filter coefficient controller,
Next, selecting the first selection means for the acoustic input signal,
Further, a noise resistant adaptive equalizer configured to select the second selecting means as a coefficient memory of the second adaptive filter to operate the filter coefficient controller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15688790A JPH0828635B2 (en) | 1990-06-14 | 1990-06-14 | Noise resistant adaptive equalizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15688790A JPH0828635B2 (en) | 1990-06-14 | 1990-06-14 | Noise resistant adaptive equalizer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0447705A JPH0447705A (en) | 1992-02-17 |
| JPH0828635B2 true JPH0828635B2 (en) | 1996-03-21 |
Family
ID=15637568
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15688790A Expired - Fee Related JPH0828635B2 (en) | 1990-06-14 | 1990-06-14 | Noise resistant adaptive equalizer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0828635B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3306600B2 (en) * | 1992-08-05 | 2002-07-24 | 三菱電機株式会社 | Automatic volume control |
| JP3964092B2 (en) * | 2000-02-17 | 2007-08-22 | アルパイン株式会社 | Audio adaptive equalizer and filter coefficient determination method |
| DE10018666A1 (en) | 2000-04-14 | 2001-10-18 | Harman Audio Electronic Sys | Dynamic sound optimization in the interior of a motor vehicle or similar noisy environment, a monitoring signal is split into desired-signal and noise-signal components which are used for signal adjustment |
| JP4094444B2 (en) * | 2003-01-31 | 2008-06-04 | 株式会社エヌ・ティ・ティ・ドコモ | Wireless communication terminal |
| JP5269175B2 (en) * | 2011-11-28 | 2013-08-21 | 株式会社東芝 | Volume control device, voice control method, and electronic device |
-
1990
- 1990-06-14 JP JP15688790A patent/JPH0828635B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0447705A (en) | 1992-02-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2685031B2 (en) | Noise cancellation method and noise cancellation device | |
| JP2930101B2 (en) | Noise canceller | |
| CA2207716C (en) | Noise canceling method and apparatus therefor | |
| US5278900A (en) | Digital echo canceller comprising a double-talk detector | |
| JP2874679B2 (en) | Noise elimination method and apparatus | |
| EP0465174B1 (en) | Adaptive active noise cancellation apparatus | |
| JP2538176B2 (en) | Eco-control device | |
| JP3141674B2 (en) | Noise reduction headphone device | |
| JPH06332474A (en) | Noise silencer | |
| EP0771515A2 (en) | Signal amplification system with automatic equalizer | |
| JP2007522705A (en) | Audio distortion compression system and filter device thereof | |
| CN1953060A (en) | Echo elimination device for microphone and method thereof | |
| JPH08241086A (en) | Noise suppressor | |
| CN113811945B (en) | Noise cancellation signal saturation control | |
| JPH0828635B2 (en) | Noise resistant adaptive equalizer | |
| JP3407392B2 (en) | Stereo echo canceller | |
| JPH06332477A (en) | Muffler | |
| US5987143A (en) | Method and apparatus for erasing acoustic echo | |
| US11942068B2 (en) | Adaptive active noise control system with unstable state handling and associated method | |
| Puder et al. | Controlling the adaptation of feedback cancellation filters-problem analysis and solution approaches | |
| JPH0844375A (en) | Noise eliminating device and noise eliminating method | |
| JP2507128B2 (en) | Eco-canceller | |
| JPH05216485A (en) | Noise elimination device | |
| JP2928967B2 (en) | Noise control device | |
| JPS61194913A (en) | Noise canceller |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |