EP0710947B1 - Verfahren und Apparat zur Geräuschunterdrückung in einem Sprachsignal und korrespondierendes System mit Echounterdrückung - Google Patents

Verfahren und Apparat zur Geräuschunterdrückung in einem Sprachsignal und korrespondierendes System mit Echounterdrückung Download PDF

Info

Publication number
EP0710947B1
EP0710947B1 EP95402385A EP95402385A EP0710947B1 EP 0710947 B1 EP0710947 B1 EP 0710947B1 EP 95402385 A EP95402385 A EP 95402385A EP 95402385 A EP95402385 A EP 95402385A EP 0710947 B1 EP0710947 B1 EP 0710947B1
Authority
EP
European Patent Office
Prior art keywords
signal
domain
voice signal
frequency
background noise
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 - Lifetime
Application number
EP95402385A
Other languages
English (en)
French (fr)
Other versions
EP0710947A1 (de
Inventor
Ivan Bourmeyster
Frédéric Lejay
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alcatel Lucent SAS
Original Assignee
Alcatel CIT SA
Alcatel SA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Alcatel CIT SA, Alcatel SA filed Critical Alcatel CIT SA
Publication of EP0710947A1 publication Critical patent/EP0710947A1/de
Application granted granted Critical
Publication of EP0710947B1 publication Critical patent/EP0710947B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10L—SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; SPEECH OR AUDIO CODING OR DECODING
    • G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
    • G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
    • G10L21/0208—Noise filtering
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S367/00—Communications, electrical: acoustic wave systems and devices
    • Y10S367/901—Noise or unwanted signal reduction in nonseismic receiving system

Definitions

  • the present invention relates generally to method and device for suppressing a noise signal in a speech signal, typically for an application to hands-free radiotelephony. It also relates to a system implementing such a device in combination with an echo canceller.
  • the electrical signal resulting from an acousto-electric conversion of a speech is mixed with a noise signal. Since the level of the noise signal in this environment is high, for example in the cockpit of a vehicle, it is necessary to implement treatments aimed at remove the noise signal in the electrical signal from word.
  • two types of suppression treatment noise are distinguished according to the prior art: the Spectral subtraction treatment and the so-called treatment by filter bank.
  • the treatment by filter bank consists of a step of separating the input signal into a plurality of time signals representative each of a band of respective predetermined frequencies, an estimation step a signal-to-noise ratio for each of these signals temporal, a step of weighting these temporal signals by respective coefficients which are each a function of the respective one of the signal-to-noise ratios for the signal considered, and a step of adding these signals weighted temporals into a resulting signal consisting of a speech signal in which the noise signal is deleted.
  • each of the signal-to-noise ratios is estimated according to the variation of the power of the time signal considered in its frequency band respectively.
  • Spectral subtraction processing uses its share in the frequency domain, typically by use FFT Fast Fourier Transform (Fast Fourier Transform) in Anglo-Saxon terminology). It has the disadvantage principle of inducing non-linear distortion in the processed speech signal that results from the loss phase information of this signal. Indeed this treatment by spectral subtraction produces such a distortion because it applies to samples resulting from the Transform of Fast Fourier of noisy speech signal to deal with squared module functions that remove information from phase, thus making this treatment non-linear.
  • the lack of linearity of the treatment by subtraction spectral impedes its effective use in combination with echo cancellation processing, such proposed by the invention because the cancellation device echo is disturbed in its operation by this loss phase information.
  • a first objective of the present invention is to provide a method of suppressing noise in a signal of word that has the advantage of significantly reducing the computing power required in terms of Instructions per Second, compared to a treatment by filter bank.
  • a second object of the invention is to provide a not inducing nonlinear distortion in the speech signal to be treated, in contrast to the treatment by spectral subtraction.
  • Another object of the invention is to provide a system comprising a noise canceling device implementing the process steps, in combination with an echo cancellation device.
  • the calculation step is preceded, for each of the K groups of frequency components, by a step of selecting some of the components frequencies having respective predetermined ranks in said each of the groups, said selected portion symmetrical with respect to the complementary of this part among the plurality of extracted frequency components.
  • production steps and synthesis are implemented respectively by means of Fast Fourier Transform and Inverse Fourier Transform.
  • the invention also provides two variants of combined system of echo cancellation and suppression of noise.
  • the frequency processing unit 100 includes in cascade a circuit of extraction of energy components 10, an estimation circuit of signal-to-noise ratio 11, a gain calculation circuit 12 and a filter coefficient synthesis circuit 13.
  • the temporal processing circuit 14 is a time filter, of finite impulse response filter type (FIR Filter in English terminology for Finite Impulse Response Filter).
  • the sampled noisy speech signal s (nT) resulting from this sampling is applied, on the one hand, to an input of the energy component extraction circuit 10 in the frequency processing unit 100, and, on the other hand, to an input of the time filter 14.
  • Figure 2 shows schematically the processing performed in the circuit 10 which receives the noisy speech signal s (nT).
  • This sampled noisy speech signal s (nT) is in the form of successive frames of samples, four of which are T (n-2), T (n-1), T (n) and T (n). +1) being represented in a first line of FIG. 2.
  • K 3 blocks of samples B (1), B (2) and B (3) , K being an integer.
  • K 3 blocks of samples are formed according to the embodiment described from, on the one hand, this frame of rank n, T (n), and, on the other hand, 2 frames T (n-2). and T (n-1), of respective ranks (n-2) and (n-1).
  • the step noted 101 in this Figure 2 is intended to simplify the implementation of subsequent processing by selecting only a part of the frequency components in each group E (1) i to E (3) i , 0 ⁇ i ⁇ 255.
  • This step is based on the following property.
  • the Fast Fourier Transform of a real signal has a pseudo-symmetry.
  • These first 129 selected frequency components are sufficient to describe each group E (k) i , 0 ⁇ i ⁇ 255, in a complete way since the other frequency components in the group, namely the last 127 components E (k) 129 to E ( k) 255 are deduced by symmetry.
  • the frequency components E (k) O to E (k) 128 which are selected in each group have indeed a character of symmetry with respect to the complement E (k) 129 to E (k) 255 of these selected components among all the components frequencies in the group that are initially produced.
  • the frequency components E (k) O to E (k) 128 are produced for each group.
  • the 129 frequency components selected in each group are decimated by 2, in order to retain only one out of two of each selected group of components. This decimation by two 102 aims to selectively remove one component out of two, relative to a given frequency, with a view to inhibiting the interaction effect that produces on this component each of the two frequency components located at two respective frequencies of each other.
  • the device 10 extracts for a cycle relating to a noisy speech signal processing frame T (n) s, (nT) 65 energy components Em j , each representative of an energy, or power, of the noisy speech signal. (nT) for the frequency, or frequency band, considered.
  • all the steps 100, 101 and 102 described with reference to FIG. 2, although improving the implementation of the method according to the invention, can be reduced to a single step consisting of the application of a single FFT Fourier transform at M 128 samples of the T (n) frame selected for the considered treatment cycle.
  • the selection step 101 may either be operated or not be operated directly on the frequency components resulting from the FFT treatment (s).
  • the 65 energy components Em j are applied to an input of the signal-to-noise ratio estimation circuit 11.
  • the circuit It estimates a signal-to-noise ratio SNRj between the noisy speech signal s (nT) and a noise signal included in this noisy speech signal, for the energy component considered Em j .
  • SNR j not Em j not / B j not in which the exponent n identifies the processing cycle relative to the frame T (n) of rank n and B j denotes a noise energy component in the energy component Em j of rank j.
  • such an estimate of the signal-to-noise ratio is based on the calculation of the estimated noise energy component in each given energy component. For example, it uses the ratio between the energy component Em j n extracted and the noise energy component B j n-1 calculated previously during a treatment cycle that preceded the considered cycle of noise signal suppression processing in the process. frame T (n). The higher this ratio, the more it indicates the existence of a speech signal for the frequency energy component Em j n considered, in which case the noise component B j (n-1) calculated with respect to the energy component Em j ( n-1) for the rank (n-1) is maintained in the noise component B j n .
  • Circuit 11 assigns a signal to noise ratio SNR j , 0 ⁇ j ⁇ 64, to each extracted energy component Emj, 0 ⁇ j ⁇ 64, according to an estimation algorithm using such a principle.
  • SNR j As a function of these 65 signal-to-noise ratios SNR j , the circuit 12 calculates for each of them a gain G j , taking for example a value comprised substantially between 0 and 1, which is directly related to the signal-to-noise ratio SNR j for the corresponding frequency component.
  • the noise signal is weak, plus the gain G j is high.
  • the noise signal component is attenuated for each frequency energy component Em j .
  • These gains G j are such that the weighting of the energy components Em j respectively by these gains would give a discrete spectrum of weighted frequency energy components, which would be representative of the noisy speech signal s (nT) in which the noise signal is substantially suppressed.
  • This circuit 13 comprises a first circuit (not shown) for duplicating the 65 calculated gains G i , in accordance with the equation given in (1).
  • These coefficients denoted C (nT), 128 in number, are applied to a first control input of the filter 14, typically FIR filter.
  • a second input of the filter 14 receives the noisy speech signal s (nT).
  • the filter 14 convolves the coefficients C (nT) with the 128 samples of the frame T (n), in a field denoise of 128 samples forming part of the speech signal noised s * (nT).
  • the method resulting from the device described above is naturally "adaptive" in the sense that the coefficients C (nT) applied to the control input of the FIR filter 14 are modified for each frame T (n), of rank n given, depending on the processing 10, 11, 12 and 13 of the samples forming the speech signal to be processed.
  • the characteristic of the noise suppression process according to the invention is to use, on the one hand, a treatment digital frequency 100 of the noisy speech signal, for produce filtering time coefficients C (nT), and, on the other hand, a digital time processing 14 of the signal of noisy speech s (nT) according to the coefficients of filtering C (nT), to produce a speech signal s * (nT) wherein the noise signal is substantially suppressed.
  • a combined system of noise suppression and echo cancellation which is included in a terminal, typically a hands-free radiotelephone, includes a microphone 2, a loudspeaker 4, a noise suppression according to the invention 1, as described previously, a temporal processing circuit 14 'and a echo canceller 3.
  • the noise suppressor 1 is identical to the device shown in FIG. 1, and mainly includes a frequency processing unit 100 and a temporal processing circuit 14.
  • the canceller echo is formed of a subtractor 30 and a circuit 31 which produces an estimated echo signal.
  • the microphone 2 receives a speech signal to be transmitted [s (t) + e (t)] formed of a signal noisy sound word s (t) added to an echo signal and).
  • This echo signal results from the acoustic coupling between the speaker 4 and microphone 2.
  • the device noise suppression 1 treats, as described previously, the speech signal to be transmitted in a speech signal transmitted denoised [s * (nT) + e * (nT)] which is applied to a first input of the subtractor 30 including a second input receives the output of circuit 31.
  • a received speech signal r (t) from a remote terminal is applied, from a to a loudspeaker input, and, on the other hand, to a loudspeaker circuit 31 input through the processing circuit temporal 14 'preceded by a sampler 14a'.
  • the circuit of temporal processing 14 ' is at each moment strictly similar to the temporal processing circuit 14 in the noise suppression device 1 (FIG. 1).
  • This characteristic is based on the fact that the estimated echo of received signal r (t) produced by the circuit 31 is to be subtracted, in the subtractor 30, to the echo signal processed by noise suppression e * (nT) in circuit 1 and not at original echo signal e (nT).
  • This circuit 14 'is therefore a pure and simple duplication of the temporal processing circuit 14 in device 1, as indicated by the arrow in broken line at both ends in Figure 3.
  • the time processing circuit 14 'is therefore associated with each moment to the same 128 filter coefficients C (nT) as the circuit 14 in the device 1.
  • a combined system of noise suppression and echo cancellation comprises a microphone 2, a loudspeaker 4, an echo canceller 3, a frequency processing 100, a processing circuit temporal 14 and a sampler 5.
  • the units 100 and circuit 14 are identical to those described in FIG.
  • the echo canceller 3 is formed of a subtractor 30 and a circuit 31 which produces an estimated echo signal ê (nT).
  • the microphone 2 receives a transmitted speech signal [s (t) + e (t)] formed of a noisy speech signal s (t) added to an echo signal e (t). This echo signal results from the coupling between the loudspeaker 4 and the microphone 2.
  • the transmitted speech signal [s (t) + e (t)] is sampled in the sampler 5 in the signal [s (nT) + e (nT)].
  • This signal sampled is applied, on the one hand, to an input of unit 100, and, on the other hand, to an input of the circuit 14 to through the subtractor 30.
  • a speech signal received in from a remote terminal r (t) is applied, from a part of an entrance to circuit 31 and, on the other hand, to a speaker input 4.
  • Circuit 31, receiving the signal r (t) produces in response an estimated echo signal ê (nT) applied to a first input of the subtractor 30, one of which second input receives the transmitted speech signal [S (nT) + e (nT)].
  • the treatments frequencies implemented in unit 100 operate on the transmitted speech signal [s (nT) + e (nT)], and secondly the temporal processing in the circuit 14, from the coefficients C (nT) produced by unit 100, operates on the difference signal, or transmitted speech signal processed by echo cancellation, [s (nT) + e (nT) -e (nT)].
  • This variant avoids "duplicating" circuit 14 in the branch including the circuit 31, as represented by the line arrow discontinuous in Figure 3 for the previous variant.

Landscapes

  • Engineering & Computer Science (AREA)
  • Human Computer Interaction (AREA)
  • Quality & Reliability (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Audiology, Speech & Language Pathology (AREA)
  • Computational Linguistics (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
  • Circuit For Audible Band Transducer (AREA)
  • Filters That Use Time-Delay Elements (AREA)

Claims (7)

  1. Verfahren zum Unterdrücken eines Rauschsignals in einem abgetasteten verrauschten Sprachsignal (s(nT)), mit den Schritten:
    digitale Verarbeitung (100) des verrauschten Sprachsignals im Frequenzbereich zum Erzeugen von zeitlichen Filterkoeffizienten (C(nT)), mit den Unterschritten:
    Extraktion einer Mehrzahl von Frequenzenergiekomponenten (Emj) in dem verrauschten Sprachsignal (s(nT)),
    Abschätzen (11), für jede der extrahierten Frequenzenergiekomponenten, eines Verhältnisses (SNRj) zwischen einem Energieniveau des verrauschten Sprachsignals (s(nT)) und einem Energieniveau des Rauschsignals,
    Bestimmen (12) einer jeweiligen Verstärkung (Gj) für jede der extrahierten Frequenzenergiekomponenten (Emj) in Abhängigkeit von dem abgeschätzen Verhältnis (SNRj) zwischen dem Energieniveau des verrauschten Sprachsignals (s(nT)) und dem Energieniveau des Rauschsignals für jede jeweils ausgewählte Frequenzkomponenten, und
    Synthese (13) der Filterkoeffizienten (C(nT)) in Abhängigkeit von den Verstärkungen (Gj) ;
    digitale Verarbeitung (14) des verrauschten Sprachsignals (s(nT)) im Zeitbereich in Abhängigkeit von den Filterkoeffizienten (C(nT)) zu einem Sprachsignal (s*(nT)), bei dem das Rauschsignal im wesentlichen unterdrückt ist.
  2. Verfahren nach dem vorhergenden Anspruch, bei dem der Schritt der Extraktion der Frequenzenergiekomponenten die folgenden Unterschritte umfasst:
    Erzeugen (100a, 100b, 100c) von K Gruppen mit jeweils einer Mehrzahl von Frequenzkomponenten (E(1)i, E(2)i, E(3)i für jeweils K verschachtelte Blöcke (B(1), B(2), B(3)) des verrauschten Sprachsignals (s(nT)), wobei K eine ganze Zahl ist, und
    Berechnen (103) eines Energiemittels von K Frequenzkomponenten von jeweils gleichem Rang (j) in den K Gruppen für die jeweils eine der extrahierten Frequenzenergiekomponenten.
  3. Verfahren nach Anspruch 2, bei dem dem Schritt des Berechnens (103) für jede der K Gruppen von Frequenzkomponenten ein Schritt des Auswählens (101) eines Teils der Frequenzkomponenten mit jeweils vorgegebenen Rängen in jeder der Gruppen (E(1)i, E(2)i, E(3)i) vorangeht, wobei der ausgewählte Teil eine Symmetrieeigenschaft in Bezug auf das Komplement dieses Teils unter der Mehrzahl der extrahierten Frequenzkomponenten aufweist.
  4. Verfahren nach einem beliebigen der Ansprüche 1 bis 3, bei dem die Schritte des Erzeugens (100a, 100b, 100c) und der Synthese (13) jeweils durch schnelle Fourier-Transformation und inverse schnelle Fourier-Transformation durchgeführt werden.
  5. Vorrichtung zur Unterdrückung eines Rauschsignals in einem abgetasteten verrauschten Sprachsignal (s(nT)), welche für jeden von aufeinanderfolgenden Verarbeitungszyklen umfasst:
    Mittel (10) zum Extrahieren einer Mehrzahl von Frequenzenergiekomponenten (Emj) in dem verrauschten Sprachsignal (s(nT)),
    Mittel (11) zum Abschätzen, für jede der extrahierten Frequenzenergiekomponenten, eines Verhältnisses (SNRj) zwischen einem Energieniveau des verrauschten Sprachsignals (s(nT)) und einem Energieniveau des Rauschsignals,
    Mittel zum Bestimmen (12) einer jeweiligen Verstärkung (Gj) für jede der extrahierten Frequenzenergiekomponenten (Emj) in Abhängigkeit von dem abgeschätzten Verhältnis (SNRj) zwischen dem Energieniveau des verrauschten Sprachsignals (s(nT)) und dem Energieniveau des Rauschsignals für jede jeweils ausgewählte Frequenzkomponente,
    Mittel (13) zum Synthetisieren der Filterkoeffizienten (C(nT)) in Abhängigkeit von den Verstärkungen (Gj), und
    Mittel zur digitalen Verarbeitung im Zeitbereich (14) des verrauschten Sprachsignals (s(nT)) in Abhängkeit von den Filterkoeffizienten (C(nT)) zu einem Sprachsignal (s(nT)), bei dem das Rauschsignal im wesentlichen unterdrückt ist.
  6. Kombiniertes System zur Echoaufhebung (3) und Rauschunterdrückung (1), mit:
    einer Rauschunterdrückungsvorrichtung (1) zum Unterdrücken eines Rauschsignals in einem zu übertragenden Sprachsignal (s(nT)+e(nT)), um ein entrauschtes Sprachsignal zu bilden,
    einem Echoaufheber (3) mit einem ersten Mittel (31) zum Erzeugen eines abgeschätzten Echosignals (ê* (t)) als Funktion eines gegebenen Sprachsignals r*(nT)) und eines Differenzsignals (s*(nT)+e*(nT)-ê*(nT)) und einem zweiten Mittel (30) zum Subtrahieren des abgeschätzten Echosignals (ê*(t)) von dem entrauschten Sprachsignal (s*(nT)+e*(nT)), um das Differenzsignal (s*(nT)+e*(nT)-ê*(nT)) zu bilden,
       dadurch gekennzeichnet, dass die Rauschunterdrückungsvorrichtung ein Mittel zur digitalen Frequenzverarbeitung (100) des zu übertragenden Sprachsignals zum Erzeugen von Filterkoeffizienten (C(nT)) im Zeitbereich umfasst, mit:
    Mitteln (10) zum Extrahieren einer Mehrzahl von Frequenzenergiekomponenten (Emj) in dem verrauschten Sprachsignal (s(nT)),
    Mitteln (11) zum Abschätzen, für jede der extrahierten Frequenzenergiekomponenten, eines Verhältnisses (SNRj) zwischen einem Energieniveau des verrauschten Sprachsignals (s(nT)) und einem Energieniveau des Rauschsignals,
    Mitteln zum Bestimmen (12) einer jeweiligen Verstärkung (Gj) für eine jede der extrahierten Frequenzenergiekomponenten (Emj) in Abhängigkeit von dem abgeschätzten Verhältnis (SNRj) zwischen dem Energieniveau des verrauschten Sprachsignals (s(nT)) und dem Energieniveau des Rauschsignals für die jede jeweils ausgewählte Frequenzkomponente,
    Mitteln (13) zum Synthetisieren der Filterkoeffizienten (C(nT)) in Abhängigkeit von den Verstärkungen (Gj),
       und dass die Rauschunterdrückungsvorrichtung ferner umfasst:
    ein erstes Mittel zur digitalen Verarbeitung im Zeitbereich (14) zur Verarbeitung des zu übertragenden Sprachsignals (s(nT)) in Abhängkeit von den Filterkoeffizienten (C(nT)) zu dem entrauschten Sprachsignal (s*(nT) + e*(nT)), bei dem das Rauschsignal im wesentlichen unterdrückt ist,
       ein zweites Mittel zur digitalen Verarbeitung im Zeitbereich (14'), des dem ersten Mittel zur Verarbeitung im Zeitbereich (14) genau entspricht, zum Verarbeiten eines von einem entfernten Endgerät empfangenen Sprachsignals (r(nT)) in Abhängigkeit von den Filterkoeffizienten (C(nT)) zu dem gegebenen Sprachsignal (r*(nT))
  7. Kombiniertes System zur Echoaufhebung (3) und Rauschunterdrückung (1) in einem zu übertragenden Sprachsignal (s(nT)+e(nT)) mit
       einem Echoaufheber (3) mit einem ersten Mittel (31) zum Erzeugen eines geschätzten Echosignals (ê*(t)) als Funktion eines von einem entfernten Endgerät empfangenen Sprachsignals (r(nT)) und eines Differenzsignals (s(nT)+e(nT)-ê(nT)) und einem zweiten Mittel (30) zum Subtrahieren des abgeschätzten Echosignals (ê*(t)) von einem zu übertragenden Sprachsignal (s(nT)+e(nT)), um das Differenzsignal (s(nT)+e(nT)-ê(nT)) zu erhalten,
       dadurch gekennzeichnet, dass es eine Rauschunterdrückungsvorrichtung (1) zum Erzeugen eines entrauschten Sprachsignals (s*(nT)+e*(nT)-ê*(nT)) durch Unterdrücken eines Rauschsignals in dem Differenzsignal s(nT)+e(nT)-ê(nT)) umfasst, wobei die Rauschunterdrückungsvorrichtung umfasst:
    einerseits ein Mittel zur digitalen Verarbeitung (100) im Frequenzbereich zum Verarbeiten des zu übertragenden Sprachsignals (s(nT)+ enT)), um zeitliche Filterkoeffizienten (C(nT)) zu erzeugen, mit:
    Mitteln (10) zum Extrahieren einer Mehrzahl von Frequenzenergiekomponenten (Emj) in dem verrauschten Sprachsignal (s(nT)),
    Mitteln (11) zum Abschätzen, für jede der extrahierten Frequenzenergiekomponenten, eines Verhältnisses (SNRj) zwischen einem Energieniveau des verrauschten Sprachsignals (s(nT)) und einem Energieniveau des Rauschsignals,
    Mitteln zum Bestimmen (12) einer jeweiligen Verstärkung (Gj) für jede jeweils extrahierte Frequenzenergiekomponente (Emj) in Abhängigkeit von dem abgeschätzen Verhältnis (SNRj) zwischen dem Energieniveau des verrauschten Sprachsignals (s(nT)) und dem Energieniveau des Rauschsignals für besagte jeweils ausgewählte Frequenzkomponente,
    Mitteln (13) zum Sythetisieren der Filterkoeffizienten (C(nT)) in Abhängigkeit von den Verstärkungen (Gj), und
    andererseits ein Mittel zur digitalen Verarbeitung im Zeitbereich (14) zur Verarbeitung des Differenzsignals s(nT)+e(nT)-ê(nT)) in Abhängigkeit von den Filterkoeffizienten (C(nT)) zu einem entrauschten Sprachsignal (s*(nT)+e*(nT)-ê*(nT)), in dem das Rauschsignal im wesentlichen unterdrückt ist.
EP95402385A 1994-10-28 1995-10-25 Verfahren und Apparat zur Geräuschunterdrückung in einem Sprachsignal und korrespondierendes System mit Echounterdrückung Expired - Lifetime EP0710947B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9412964A FR2726392B1 (fr) 1994-10-28 1994-10-28 Procede et dispositif de suppression de bruit dans un signal de parole, et systeme avec annulation d'echo correspondant
FR9412964 1994-10-28

Publications (2)

Publication Number Publication Date
EP0710947A1 EP0710947A1 (de) 1996-05-08
EP0710947B1 true EP0710947B1 (de) 2003-01-08

Family

ID=9468340

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95402385A Expired - Lifetime EP0710947B1 (de) 1994-10-28 1995-10-25 Verfahren und Apparat zur Geräuschunterdrückung in einem Sprachsignal und korrespondierendes System mit Echounterdrückung

Country Status (10)

Country Link
US (1) US5680393A (de)
EP (1) EP0710947B1 (de)
JP (2) JPH08213936A (de)
AT (1) ATE230890T1 (de)
AU (1) AU698081B2 (de)
CA (1) CA2161575A1 (de)
DE (1) DE69529328T2 (de)
FI (1) FI955086A (de)
FR (1) FR2726392B1 (de)
NZ (1) NZ280224A (de)

Families Citing this family (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2729804B1 (fr) * 1995-01-24 1997-04-04 Matra Communication Annuleur d'echo acoustique a filtre adaptatif et passage dans le domaine frequentiel
JP2921472B2 (ja) * 1996-03-15 1999-07-19 日本電気株式会社 音声および雑音の除去装置、音声認識装置
US6192087B1 (en) 1996-11-15 2001-02-20 Conexant Systems, Inc. Method and apparatus for spectral shaping in signal-point limited transmission systems
US6278744B1 (en) 1996-11-15 2001-08-21 Conexant Systems, Inc. System for controlling and shaping the spectrum and redundancy of signal-point limited transmission
US5933495A (en) * 1997-02-07 1999-08-03 Texas Instruments Incorporated Subband acoustic noise suppression
JP3361724B2 (ja) * 1997-06-11 2003-01-07 沖電気工業株式会社 エコーキャンセラ装置
US7853024B2 (en) * 1997-08-14 2010-12-14 Silentium Ltd. Active noise control system and method
IL121555A (en) * 1997-08-14 2008-07-08 Silentium Ltd Active acoustic noise reduction system
US6144735A (en) * 1998-03-12 2000-11-07 Westell Technologies, Inc. Filters for a digital subscriber line system for voice communication over a telephone line
US6115466A (en) * 1998-03-12 2000-09-05 Westell Technologies, Inc. Subscriber line system having a dual-mode filter for voice communications over a telephone line
US6717991B1 (en) * 1998-05-27 2004-04-06 Telefonaktiebolaget Lm Ericsson (Publ) System and method for dual microphone signal noise reduction using spectral subtraction
US6549586B2 (en) * 1999-04-12 2003-04-15 Telefonaktiebolaget L M Ericsson System and method for dual microphone signal noise reduction using spectral subtraction
US6122610A (en) * 1998-09-23 2000-09-19 Verance Corporation Noise suppression for low bitrate speech coder
US6507623B1 (en) * 1999-04-12 2003-01-14 Telefonaktiebolaget Lm Ericsson (Publ) Signal noise reduction by time-domain spectral subtraction
US6487257B1 (en) * 1999-04-12 2002-11-26 Telefonaktiebolaget L M Ericsson Signal noise reduction by time-domain spectral subtraction using fixed filters
US6411656B1 (en) * 1999-04-30 2002-06-25 3Com Corporation Echo cancelling softmodem
DE19925046A1 (de) * 1999-06-01 2001-05-03 Alcatel Sa Verfahren und Vorrichtung zur Unterdrückung von Rauschen und Echos
US6137880A (en) * 1999-08-27 2000-10-24 Westell Technologies, Inc. Passive splitter filter for digital subscriber line voice communication for complex impedance terminations
US7225001B1 (en) 2000-04-24 2007-05-29 Telefonaktiebolaget Lm Ericsson (Publ) System and method for distributed noise suppression
DE10043064B4 (de) * 2000-09-01 2004-07-08 Dietmar Dr. Ruwisch Verfahren und Vorrichtung zur Elimination von Lautsprecherinterferenzen aus Mikrofonsignalen
FR2820227B1 (fr) * 2001-01-30 2003-04-18 France Telecom Procede et dispositif de reduction de bruit
US6963760B2 (en) * 2001-10-01 2005-11-08 General Motors Corporation Method and apparatus for generating DTMF tones using voice-recognition commands during hands-free communication in a vehicle
JP2004061617A (ja) * 2002-07-25 2004-02-26 Fujitsu Ltd 受話音声処理装置
KR20050026320A (ko) * 2003-09-09 2005-03-15 삼성전자주식회사 데이터 재생 장치 및 방법
US7162212B2 (en) * 2003-09-22 2007-01-09 Agere Systems Inc. System and method for obscuring unwanted ambient noise and handset and central office equipment incorporating the same
US7065206B2 (en) 2003-11-20 2006-06-20 Motorola, Inc. Method and apparatus for adaptive echo and noise control
US20070033030A1 (en) * 2005-07-19 2007-02-08 Oded Gottesman Techniques for measurement, adaptation, and setup of an audio communication system
EP1941492A1 (de) * 2005-10-25 2008-07-09 Anocsys AG Verfahren zum schätzen eines nutzsignals mit hilfe eines adaptiven prozesses
US7774396B2 (en) * 2005-11-18 2010-08-10 Dynamic Hearing Pty Ltd Method and device for low delay processing
AU2006338843B2 (en) * 2006-02-21 2012-04-05 Cirrus Logic International Semiconductor Limited Method and device for low delay processing
JP4827661B2 (ja) * 2006-08-30 2011-11-30 富士通株式会社 信号処理方法及び装置
US8855329B2 (en) * 2007-01-22 2014-10-07 Silentium Ltd. Quiet fan incorporating active noise control (ANC)
US7515703B1 (en) 2008-05-19 2009-04-07 International Business Machines Corporation Method and system for determining conference call embellishment tones and transmission of same
JP5056617B2 (ja) * 2008-06-26 2012-10-24 沖電気工業株式会社 暗騒音抑圧・エコー消去装置、方法及びプログラム
KR101737824B1 (ko) * 2009-12-16 2017-05-19 삼성전자주식회사 잡음 환경의 입력신호로부터 잡음을 제거하는 방법 및 그 장치
JP5672437B2 (ja) * 2010-09-14 2015-02-18 カシオ計算機株式会社 雑音抑制装置、雑音抑制方法およびプログラム
JP6182524B2 (ja) 2011-05-11 2017-08-16 シレンティウム リミテッド ノイズ・コントロールのデバイス、システム、および方法
US9928824B2 (en) 2011-05-11 2018-03-27 Silentium Ltd. Apparatus, system and method of controlling noise within a noise-controlled volume
KR101306868B1 (ko) * 2011-12-21 2013-09-10 황정진 미확인 시스템 모델링 방법 및 이를 이용한 하울링 제거 오디오 시스템
US8878678B2 (en) * 2012-05-29 2014-11-04 Cisco Technology, Inc. Method and apparatus for providing an intelligent mute status reminder for an active speaker in a conference
JP2014085609A (ja) * 2012-10-26 2014-05-12 Sony Corp 信号処理装置および方法、並びに、プログラム
CN103795473B (zh) * 2012-11-02 2017-04-12 华为技术有限公司 消除工频干扰的方法和系统
CN103248337A (zh) * 2013-05-29 2013-08-14 中国电子科技集团公司第二十二研究所 一种空时级联抑制斜向探测电离图外部干扰的方法
CN104702245A (zh) * 2015-02-04 2015-06-10 航天科工深圳（集团）有限公司 抑制浪涌雷电波干扰的方法
US11488615B2 (en) 2018-05-21 2022-11-01 International Business Machines Corporation Real-time assessment of call quality
JP7348812B2 (ja) 2019-10-31 2023-09-21 東京都公立大学法人 雑音抑制装置、雑音抑制方法及び音声入力機器

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4628529A (en) 1985-07-01 1986-12-09 Motorola, Inc. Noise suppression system
JPS6343451A (ja) * 1986-08-11 1988-02-24 Mitsubishi Electric Corp 拡声通話回路
JPS63108822A (ja) * 1986-10-25 1988-05-13 Nippon Telegr & Teleph Corp <Ntt> 音声通話信号の雑音抑圧装置
AU633673B2 (en) * 1990-01-18 1993-02-04 Matsushita Electric Industrial Co., Ltd. Signal processing device
US5561667A (en) * 1991-06-21 1996-10-01 Gerlach; Karl R. Systolic multiple channel band-partitioned noise canceller
JPH0563609A (ja) * 1991-09-05 1993-03-12 Fujitsu Ltd エコーキヤンセラ方式
FI92535C (fi) * 1992-02-14 1994-11-25 Nokia Mobile Phones Ltd Kohinan vaimennusjärjestelmä puhesignaaleille
US5416847A (en) * 1993-02-12 1995-05-16 The Walt Disney Company Multi-band, digital audio noise filter
US5329587A (en) * 1993-03-12 1994-07-12 At&T Bell Laboratories Low-delay subband adaptive filter
US5406622A (en) * 1993-09-02 1995-04-11 At&T Corp. Outbound noise cancellation for telephonic handset

Also Published As

Publication number Publication date
FI955086A (fi) 1996-04-29
JPH08213936A (ja) 1996-08-20
JP4567655B2 (ja) 2010-10-20
FR2726392A1 (fr) 1996-05-03
JP2007129736A (ja) 2007-05-24
FR2726392B1 (fr) 1997-01-10
US5680393A (en) 1997-10-21
AU3444295A (en) 1996-05-09
DE69529328D1 (de) 2003-02-13
FI955086A0 (fi) 1995-10-25
NZ280224A (en) 1997-02-24
DE69529328T2 (de) 2003-09-04
AU698081B2 (en) 1998-10-22
EP0710947A1 (de) 1996-05-08
ATE230890T1 (de) 2003-01-15
CA2161575A1 (fr) 1996-04-29

Similar Documents

Publication Publication Date Title
EP0710947B1 (de) Verfahren und Apparat zur Geräuschunterdrückung in einem Sprachsignal und korrespondierendes System mit Echounterdrückung
EP0748555B1 (de) Akustischer echokompensator mit filterung in frequenzteilbändern
EP0103257B1 (de) Verfahren und Schaltung zur Abschwächung des Eigenrauschens
CA2266654C (fr) Procede et dispositif d&#39;egalisation aveugle des effets d&#39;un canal de transmission sur un signal de parole numerique
US7620172B2 (en) Method and system for eliminating noises and echo in voice signals
EP0752181B1 (de) Echokompensation mit adaptivem filter im frequenzbereich
WO2007099222A1 (fr) Procede de debruitage d&#39;un signal audio
EP0998166A1 (de) Anordnung zur Verarbeitung von Audiosignalen, Empfänger und Verfahren zum Filtern und Wiedergabe eines Nutzsignals in Gegenwart von Umgebungsgeräusche
FR2789823A1 (fr) Filtres a sous-bandes unilaterales
EP0692883B1 (de) Verfahren zur blinden Entzerrung, und dessen Anwendung zur Spracherkennung
EP0884926B1 (de) Verfahren und Vorrichtung zur optimierten Verarbeitung eines Störsignals während einer Tonaufnahme
EP1039736B1 (de) Verfahren und Vorrichtung zur adaptiven Identifikation und entsprechender adaptiver Echokompensator
FR3009121A1 (fr) Procede de suppression de la reverberation tardive d&#39;un signal sonore
EP1103138B1 (de) Digitale signalverarbeitung mit frequenzfilterung und mit verminderung der rechenkomplexität
FR2974443A1 (fr) Procede et systeme de reduction du bruit
JP2000134138A (ja) 副帯エコ―を打ち消すための無遅延システム
US7177805B1 (en) Simplified noise suppression circuit
EP1438815A1 (de) Zwischensymbolstörungslöscher
EP0824798B1 (de) Adaptive teilbandfiltrierung
FR2678453A1 (fr) Poste telephonique a dispositif d&#39;annulation d&#39;echo.

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB IT LI NL SE

17P Request for examination filed

Effective date: 19961011

17Q First examination report despatched

Effective date: 19991230

RIC1 Information provided on ipc code assigned before grant

Free format text: 7G 10L 21/02 A

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

RIC1 Information provided on ipc code assigned before grant

Free format text: 7G 10L 21/02 A

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: ALCATEL

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE DK ES FR GB IT LI NL SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20030108

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20030108

REF Corresponds to:

Ref document number: 230890

Country of ref document: AT

Date of ref document: 20030115

Kind code of ref document: T

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REF Corresponds to:

Ref document number: 69529328

Country of ref document: DE

Date of ref document: 20030213

Kind code of ref document: P

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20030311

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20030408

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20030730

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20031031

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20031031

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20031031

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20031009

BERE Be: lapsed

Owner name: *ALCATEL

Effective date: 20031031

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: FR

Ref legal event code: CD

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

Free format text: REGISTERED BETWEEN 20131114 AND 20131120

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20131022

Year of fee payment: 19

Ref country code: GB

Payment date: 20131021

Year of fee payment: 19

Ref country code: DE

Payment date: 20131021

Year of fee payment: 19

Ref country code: FR

Payment date: 20131022

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20131028

Year of fee payment: 19

REG Reference to a national code

Ref country code: FR

Ref legal event code: GC

Effective date: 20140717

REG Reference to a national code

Ref country code: FR

Ref legal event code: RG

Effective date: 20141016

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69529328

Country of ref document: DE

REG Reference to a national code

Ref country code: SE

Ref legal event code: EUG

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20141025

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20141025

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20141026

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150501

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20150630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20141031

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20141025