WO2020045898A1

WO2020045898A1 - Apparatus for removing stereo noise and method for removing stereo noise

Info

Publication number: WO2020045898A1
Application number: PCT/KR2019/010719
Authority: WO
Inventors: 박형민; 조병준
Original assignee: 서강대학교산학협력단
Priority date: 2018-08-27
Filing date: 2019-08-22
Publication date: 2020-03-05

Abstract

In a method for removing noise according to an embodiment of the present invention, a first estimated output signal calculated on the basis of a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to a previous frame can be provided. A first current far-end channel filter corresponding to a current frame may be updated according to the first estimated output signal and the first previous far-end channel filter. A second estimated output signal calculated on the basis of the first current far-end channel filter, the second previous far-end channel filter, and the input signal may be provided. A second current far-end channel filter corresponding to the current frame may be updated according to the second estimated output signal and the second previous far-end channel filter. A result signal calculated on the basis of the first current far-end channel filter, the second current far-end channel filter, and the input signal may be provided. Using the method for removing noise according to the present invention, it is possible to provide a speech signal from which noise is removed by removing a stereo echo signal from an input signal.

Description

Stereo Noise Canceller and Stereo Noise Canceling Method

The present invention relates to a method for removing stereo noise.

When the voice is transmitted through a microphone in a predetermined space and the speaker is listened to the voice, the voice transmitted to the microphone may be transferred back to the microphone through the speaker, thereby generating noise. In particular, when the voice is transmitted to the audience by using the plurality of speakers, the sound source of the noise transmitted back to the microphone may be plural. At present, various studies for removing noise caused by the stereo echo signal have been conducted.

An object of the present invention is to provide a stereo noise removing method for removing a stereo echo signal.

An object of the present invention is to provide a stereo noise removing device for removing a stereo echo signal.

In order to solve this problem, in the noise removing method according to an exemplary embodiment of the present invention, a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to a previous frame are used. A calculated first estimated output signal can be provided. The first current far-end channel filter corresponding to the current frame may be updated according to the first estimated output signal and the first previous far-end channel filter. A second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal may be provided. The second current far-end channel filter corresponding to the current frame may be updated according to the second estimated output signal and the second previous far-end channel filter. A result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal may be provided.

In an embodiment, the providing of the first estimated output signal may calculate a first correlation coefficient or a power ratio based on the first previous wave-end channel filter and the second previous wave-end channel filter. . The first estimated output signal may be calculated according to the first correlation coefficient or the power ratio.

In an embodiment, in the updating of the first current far-end channel filter, a first variance may be estimated based on the first estimated output signal. A first inverse autocorrelation matrix may be generated based on the first variance.

In one embodiment, the first dispersion may be determined by the first estimated output signal provided based on the first previous far-end channel filter and the second previous far-end channel filter.

In an embodiment, the providing of the second estimated output signal may calculate a second correlation coefficient or power ratio based on the first current far-end channel filter and the second previous far-end channel filter. The second estimated output signal may be calculated according to the second correlation coefficient or power ratio.

In an embodiment, updating the second current far-end channel filter may estimate 2 variances based on the second estimated output signal. A second inverse autocorrelation matrix may be generated based on the second variance.

In one embodiment, the second variance may be determined by the second estimated output signal provided based on the first current far-end channel filter and the second previous far-end channel filter.

In an embodiment, the providing of the resultant signal may calculate a third correlation coefficient or a power ratio based on the first current far-end channel filter and the second current far-end channel filter. The result signal may be calculated according to the third correlation coefficient or the power ratio.

In order to solve this problem, in the stereo noise removing method according to the embodiment of the present invention, an initial value may be set. Providing a first estimated output signal calculated based on a first previous far-end channel filter corresponding to a previous frame, a second previous far-end channel filter, and an input signal, wherein the first estimated output signal And a first current far-end channel filter corresponding to the current frame according to the first previous far-end channel filter. Providing a second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal, wherein the second estimated output signal and the second previous wave- The second current far-end channel filter corresponding to the current frame may be updated according to the end channel filter. A result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal may be provided.

The updating of the first current far-end channel filter may include generating a first correlation coefficient or a power ratio based on the first previous far-end channel filter and the second previous far-end channel filter. Can be calculated The first estimated output signal may be calculated according to the first correlation coefficient or the power ratio. A first variance of the first estimated output signal may be estimated. A first inverse autocorrelation matrix (IACM1) calculated based on the first variance may be generated.

In an embodiment, the updating of the second current far-end channel filter may include generating a second correlation coefficient or a power ratio based on the first current far-end channel filter and the second previous far-end channel filter. Can be calculated The second estimated output signal may be calculated according to the second correlation coefficient or power ratio. A second variance of the second estimated output signal may be estimated. A second inverse autocorrelation matrix may be generated based on the second variance.

In order to solve this problem, the apparatus for removing noise according to the embodiment of the present invention may include a first estimator, a first filter unit, a second estimator, a second filter unit, and an output unit. The first estimator may provide a first estimated output signal calculated based on a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to the previous frame. The first filter may update the first current far-end channel filter corresponding to the current frame according to the first estimated output signal and the first previous far-end channel filter. The second estimator may provide a second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal. The second filter may update the second current far-end channel filter corresponding to the current frame according to the second estimated output signal and the second previous far-end channel filter. The output unit may provide a result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal.

In example embodiments, the first estimated output signal may be calculated according to a first correlation coefficient or a power ratio calculated based on the first previous wave-end channel filter and the second previous wave-end channel filter. .

In order to solve this problem, the stereo noise removing apparatus according to the embodiment of the present invention may include an initialization unit, a first estimator, a first filter unit, a second estimator, a second filter unit, and an output unit. The initialization unit may set an initial value. The first estimator may provide a first estimated output signal calculated based on a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to the previous frame. The first filter may update the first current far-end channel filter corresponding to the current frame according to the first estimated output signal and the first previous far-end channel filter. The second estimator may provide a second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal. The second filter may update the second current far-end channel filter corresponding to the current frame according to the second estimated output signal and the second previous far-end channel filter. The output unit may provide a result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal.

In example embodiments, the second estimated output signal may be calculated according to a second correlation coefficient or a power ratio calculated based on the first current far-end channel filter and the second previous far-end channel filter. .

In addition to the technical task of the present invention mentioned above, other features and advantages of the present invention will be described below, or from such description and description will be clearly understood by those skilled in the art.

According to the present invention as described above has the following effects.

In the noise removing method according to the present invention, a voice signal from which noise is removed may be provided by removing a stereo echo signal from a micro-input signal.

The noise removing device according to the present invention can provide a voice signal from which noise is removed by removing a stereo echo signal from a micro-input signal.

In addition, other features and advantages of the present invention may be newly understood through the embodiments of the present invention.

1 is a view for explaining embodiments of the present invention.

2 is a flowchart illustrating a noise removing method according to embodiments of the present invention.

3 is a flowchart illustrating a process of providing a first estimated output signal according to an embodiment of the present invention.

4 is a flowchart illustrating an update process of a first current far-end channel filter according to an embodiment of the present invention.

FIG. 5 is a diagram for describing a first wave-end channel filter that varies with a frame.

FIG. 6 is a diagram for describing a first wave-end channel filter included in embodiments of the present invention.

7 is a flowchart illustrating a process of providing a second estimated output signal according to an embodiment of the present invention.

8 is a flowchart illustrating a process of updating a second current far-end channel filter according to an embodiment of the present invention.

FIG. 9 is a diagram for describing a second wave-end channel filter that varies with a frame.

FIG. 10 is a diagram for describing a second wave-end channel filter included in embodiments of the present invention.

11 is a flowchart illustrating a process of providing a result signal according to an embodiment of the present invention.

12 is a flowchart illustrating a stereo noise removing method according to embodiments of the present invention.

13 is a diagram illustrating an apparatus for removing noise according to embodiments of the present invention.

14 is a diagram illustrating an apparatus for removing stereo noise according to embodiments of the present invention.

15 is a flowchart illustrating a method of removing mono noise according to embodiments of the present invention.

16 is a flowchart illustrating an update process of a current far-end channel filter according to an embodiment of the present invention.

In the present specification, in adding reference numerals to components of each drawing, it should be noted that the same components have the same number as much as possible even though they are displayed on different drawings.

On the other hand, the meaning of the terms described herein will be understood as follows.

The singular forms “a,” “an” and “the” are to be understood as including plural forms, unless the context clearly indicates otherwise.

It is to be understood that the term "comprises" or "having" does not preclude the existence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

Hereinafter, with reference to the accompanying drawings will be described in detail preferred embodiments of the present invention designed to solve the above problems.

1 is a view for explaining embodiments of the present invention, Figure 2 is a flow chart illustrating a noise removing method according to embodiments of the present invention.

1 and 2, in the method of removing noise according to an exemplary embodiment of the present invention, a first previous far-end channel filter PFE_F1 and a second previous far-end corresponding to a previous frame PF may be used. The first estimated output signal EO_S1 calculated based on the channel filter PFE_F2 and the input signal IN_S may be provided (S100). The input signal IN_S may include a near-end signal NE_S, a first wave-end signal FE_S1, and a second wave-end signal FE_S2.

For example, the near-end signal NE_S may be a pure voice signal without the stereo echo signals FE_S1 and FE_S2. The first wave-end signal FE_S1 may be an echo signal provided from the first sound source 21 such as a speaker disposed in the first direction with respect to the microphone 23. The first direction may indicate the left side of the microphone 23. The second wave-end signal FE_S2 may be an echo signal provided from the second sound source 22 such as a speaker disposed in the second direction with respect to the microphone 23. The second direction may indicate the right side based on the microphone 23.

For example, the frame provided after the first frame may be a second frame. Here, when the second frame is the current frame CF, the first frame may be the previous frame PF. In this case, the first previous far-end channel filter PFE_F1 may be a far-end channel filter in the first direction in the first frame. Also, the second previous far-end channel filter PFE_F2 may be a far-end channel filter in a second direction in the first frame.

The first estimated output signal EO_S1 is

The first estimated output signal EO_S1 may be expressed by Equation 1 below.

[Equation 1]

here,

Is the input signal IN_S,

A first previous far-end channel filter (PFE_F1),

Is the first wave-end signal FE_S1,

Is the second previous far-end channel filter (PFE_F2),

Is the second wave-end signal FE_S2,

May be a first correlation coefficient or a power ratio, m may be a sample index, and k may be a frequency index.

The first current far-end channel filter CFE_F1 corresponding to the current frame CF may be updated according to the first estimated output signal EO_S1 and the first previous far-end channel filter PFE_F1. There is (S200).

For example, the frame provided after the first frame may be a second frame. Here, when the second frame is the current frame CF, the first frame may be the previous frame PF. In this case, the first current far-end channel filter CFE_F1 may be a far-end channel filter in the first direction in the second frame.

The first current far-end channel filter CFE_F1 is

The first current far-end channel filter CFE_F1 may be expressed as Equation 2 below.

[Equation 2]

here,

Is the first current far-end channel filter CFE_F1,

Is the first previous far-end channel filter PFE_F1,

May be the first Kalman.

The second estimated output signal EO_S2 calculated based on the first current far-end channel filter CFE_F1, the second previous far-end channel filter PFE_F2, and the input signal IN_S may be provided (S300). .

The second estimated output signal EO_S2 is

The second estimated output signal EO_S2 may be represented by Equation 3 below.

[Equation 3]

here,

Is the input signal IN_S,

A first previous far-end channel filter (PFE_F1),

Is the first wave-end signal FE_S1,

Is the second previous far-end channel filter (PFE_F2),

Is the second wave-end signal FE_S2,

May be a second correlation coefficient or power ratio, m may be a sample index, and k may be a frequency index.

The second current far-end channel filter CFE_F2 corresponding to the current frame CF may be updated according to the second estimated output signal EO_S2 and the second previous far-end channel filter PFE_F2 (S400).

For example, the frame provided after the first frame may be a second frame. Here, when the second frame is the current frame CF, the first frame may be the previous frame PF. In this case, the second current far-end channel filter CFE_F2 may be a far-end channel filter in the second direction in the second frame.

The second current far-end channel filter CFE_F2 is

The second current far-end channel filter CFE_F2 may be expressed by Equation 4 below.

[Equation 4]

here,

Is the second current far-end channel filter (CFE_F2),

Is the second previous far-end channel filter (PFE_F2),

May be the second Kalman.

In operation S500, a result signal OUT_S calculated based on the first current far-end channel filter CFE_F1, the second current far-end channel filter CFE_F2, and the input signal IN_S may be provided.

The result signal OUT_S is

The result signal OUT_S may be represented by Equation 5 below.

[Equation 5]

here,

Is the input signal IN_S,

Is the first current far-end channel filter CFE_F1,

Is the first wave-end signal FE_S1,

Is the second current far-end channel filter (CFE_F2),

Is the second wave-end signal FE_S2,

May be a third correlation coefficient or power ratio, m may be a sample index, and k may be a frequency index.

The noise removing method according to the present invention can provide a voice signal from which noise is removed by removing the stereo echo signal from the input signal IN_S.

In addition, although embodiments of the present invention describe stereo echo signal cancellation, techniques according to embodiments of the present invention may be applied to mono echo signal cancellation.

Referring to FIG. 3, the providing of the first estimated output signal EO_S1 may be performed based on a first previous far-end channel filter PFE_F1 and a second previous far-end channel filter PFE_F2. The first correlation coefficient or the power ratio may be calculated (S110).

The first correlation coefficient or power ratio

It may be represented by, and the first correlation coefficient or power ratio may be expressed as Equation 6.

[Equation 6]

Is the first previous far-end channel filter PFE_F1,

Is the first wave-end signal FE_S1,

Is the second previous far-end channel filter (PFE_F2),

Is the second wave-end signal FE_S2,

May be a first weight, m is a sample index, and k may be a frequency index.

The first estimated output signal EO_S1 may be calculated according to the first correlation coefficient or the power ratio (S130). For example, the first estimated output signal EO_S1 may be expressed as Equation 1 below.

FIG. 4 is a flowchart illustrating an update process of the first current far-end channel filter CFE_F1 according to an embodiment of the present invention, and FIG. 5 illustrates a first wave-end channel filter that varies according to a frame. 6 is a diagram for describing a first wave-end channel filter included in embodiments of the present invention.

4 to 6, in the updating of the first current far-end channel filter CFE_F1, the first dispersion VAR1 may be estimated based on the first estimated output signal EO_S1 (S210).

For example, the first variance VAR1 is

The first dispersion VAR1 may be expressed by Equation 7 below.

[Equation 7]

here,

May be a variance estimate calculated according to the Decision-directed (DD) method,

Is a randomly determined second weight value,

May represent the first estimated output signal EO_S1.

In one embodiment, the first variance VAR1 is a first estimated output provided based on a first previous far-end channel filter PFE_F1 and a second previous far-end channel filter PFE_F2. It may be determined by the signal EO_S1.

A first inverse autocorrelation matrix IACM1 calculated based on the first variance VAR1 may be generated (S230).

For example, the first inverse autocorrelation matrix may be expressed as Equation (8).

[Equation 8]

here,

Is the first forgetting factor (FF1),

And

May be included in the first inverse autocorrelation matrix.

Referring to FIG. 7, in the providing of the second estimated output signal EO_S2, the second correlation coefficient may be based on the first current far-end channel filter CFE_F1 and the second previous far-end channel filter PFE_F2. The power ratio may be calculated (S310).

The second correlation coefficient or power ratio

The second correlation coefficient or power ratio may be expressed by Equation 9 below.

[Equation 9]

Is the first previous far-end channel filter PFE_F1,

Is the first current far-end channel filter CFE_F1,

Is the first wave-end signal FE_S1,

Is the second previous far-end channel filter (PFE_F2),

Is the second wave-end signal FE_S2,

May be a first weight, m is a sample index, and k may be a frequency index.

The second estimated output signal EO_S2 may be calculated according to the second correlation coefficient or the power ratio (S330). For example, the second estimated output signal EO_S2 may be expressed as shown in [Equation 3].

FIG. 8 is a flowchart illustrating an update process of a second current far-end channel filter CFE_F2 according to an embodiment of the present invention, and FIG. 9 illustrates a second wave-end channel filter that varies according to a frame. FIG. 10 is a diagram for describing a second wave-end channel filter included in embodiments of the present invention.

8 to 10, in the updating of the second current far-end channel filter CFE_F2, two variances may be estimated based on the second estimated output signal EO_S2 (S410).

For example, the second variance VAR2 is

The second dispersion VAR2 may be expressed by Equation 10.

[Equation 10]

here,

Is the first variance (VAR1),

Is a randomly determined second weight value,

May represent the second estimated output signal EO_S2.

The second dispersion VAR2 may be determined by the second estimated output signal EO_S2 provided based on the first current far-end channel filter CFE_F1 and the second previous far-end channel filter PFE_F2.

A second inverse autocorrelation matrix IACM2 calculated based on the second variance VAR2 may be generated (S430).

For example, the second inverse autocorrelation matrix may be expressed as Equation 11 below.

[Equation 11]

here,

Is a second forgetting factor (FF2),

And

May be included in the second inverse autocorrelation matrix.

Referring to FIG. 11, in the providing of the result signal OUT_S, the third correlation coefficient or the power ratio is determined based on the first current far-end channel filter CFE_F1 and the second current far-end channel filter CFE_F2. Can be calculated (S510).

The third correlation coefficient or power ratio

The third correlation coefficient or power ratio may be expressed by Equation 12.

[Equation 12]

Is the first current far-end channel filter CFE_F1,

Is the first wave-end signal FE_S1,

Is the second current far-end channel filter (CFE_F2),

Is the second wave-end signal FE_S2,

May be a first weight, m is a sample index, and k may be a frequency index.

The result signal OUT_S may be calculated according to the third correlation coefficient or the power ratio. For example, the result signal OUT_S may be expressed as shown in [Equation 5].

12, in the stereo noise removing method according to an embodiment of the present invention, an initial value may be set (S100). The first estimated output signal calculated based on the first previous far-end channel filter, the second previous far-end channel filter PFE_F2 and the input signal IN_S corresponding to the previous frame PF ( A first current far-end channel filter corresponding to the current frame CF by providing EO_S1 and according to the first estimated output signal EO_S1 and the first previous far-end channel filter PFE_F1. CFE_F1) may be updated (S200). Provide a second estimated output signal EO_S2 calculated based on the first current far-end channel filter CFE_F1, the second previous far-end channel filter PFE_F2, and the input signal IN_S, and generate a second estimated output. The second current far-end channel filter CFE_F2 corresponding to the current frame CF may be updated according to the signal EO_S2 and the second previous far-end channel filter PFE_F2 (S300). In operation S400, a result signal OUT_S calculated based on the first current far-end channel filter CFE_F1, the second current far-end channel filter CFE_F2, and the input signal IN_S may be provided.

In an embodiment, the updating of the first current far-end channel filter CFE_F1 may include a first previous far-end channel filter PFE_F1 and a second previous far-end channel filter PFE_F2. Based on the first correlation coefficient or the power ratio can be calculated. The first estimated output signal EO_S1 may be calculated according to the first correlation coefficient or the power ratio. A first dispersion VAR1 of the first estimated output signal EO_S1 may be estimated. A first inverse autocorrelation matrix IACM1 calculated based on the first variance VAR1 may be generated.

In an embodiment, the updating of the second current far-end channel filter CFE_F2 may be performed based on the first current far-end channel filter CFE_F1 and the second previous far-end channel filter PFE_F2. The correlation coefficient or power ratio can be calculated. The second estimated output signal EO_S2 may be calculated according to the second correlation coefficient or the power ratio. The second dispersion VAR2 of the second estimated output signal EO_S2 may be estimated. A second inverse autocorrelation matrix IACM2 calculated based on the second variance VAR2 may be generated.

Referring to FIG. 13, the noise removing apparatus 10 according to an exemplary embodiment of the present invention may include a first estimator 100, a first filter unit 200, a second estimator 300, and a second filter unit 400. ), And may include an output unit 500.

The first estimator 100 is based on the first previous far-end channel filter, the second previous far-end channel filter PFE_F2 and the input signal IN_S corresponding to the previous frame PF. The calculated first estimated output signal EO_S1 may be provided. The first filter unit 200 corresponds to the first current far-end channel corresponding to the current frame CF according to the first estimated output signal EO_S1 and the first previous far-end channel filter PFE_F1. The filter CFE_F1 may be updated.

The second estimator 300 calculates a second estimated output signal EO_S2 based on the first current far-end channel filter CFE_F1, the second previous far-end channel filter PFE_F2, and the input signal IN_S. Can be provided. The second filter unit 400 applies the second current far-end channel filter CFE_F2 corresponding to the current frame CF according to the second estimated output signal EO_S2 and the second previous far-end channel filter PFE_F2. You can update it.

The output unit 500 may provide a result signal OUT_S calculated based on the first current far-end channel filter CFE_F1, the second current far-end channel filter CFE_F2, and the input signal IN_S. .

According to an embodiment, the first correlation coefficient or the power ratio is calculated based on the first previous far-end channel filter PFE_F1 and the second previous far-end channel filter PFE_F2. The estimated output signal EO_S1 may be calculated.

Referring to FIG. 14, the stereo noise removing apparatus 20 according to an exemplary embodiment of the present invention may include an initializer 600, a first estimator 100, a first filter unit 200, and a second estimator 300. The second filter unit 400 may include an output unit 500.

The initialization unit 600 may set an initial value. The initial value set by the initialization unit 600 may be the initial value IV of the first variance VAR1 and the second variance VAR2. The first estimator 100 is based on the first previous far-end channel filter, the second previous far-end channel filter PFE_F2 and the input signal IN_S corresponding to the previous frame PF. The calculated first estimated output signal EO_S1 may be provided. The first filter unit 200 corresponds to the first current far-end channel corresponding to the current frame CF according to the first estimated output signal EO_S1 and the first previous far-end channel filter PFE_F1. The filter CFE_F1 may be updated.

In one embodiment, the second estimated output signal EO_S2 according to the second correlation coefficient or the power ratio calculated based on the first current far-end channel filter CFE_F1 and the second previous far-end channel filter PFE_F2. ) Can be calculated.

FIG. 15 is a flowchart illustrating a method of removing mono noise according to embodiments of the present invention, and FIG. 16 is a flowchart illustrating an update process of a current far-end channel filter according to an embodiment of the present invention.

1, 15, and 16, in the case of removing the mono echo signal, the first wave-end signal FE_S1 or the second wave-end signal FE_S2 may be zero. An estimated output signal EO_S calculated based on the previous far-end channel filter PFE_F and the input signal IN_S corresponding to the previous frame PF may be provided (S1000). The input signal IN_S may include a near-end signal NE_S and a far-end signal FE_S. In this case, the estimated output signal E0_S1 may be expressed as in Equation 13.

[Equation 13]

The current far-end channel filter CFE_F corresponding to the current frame CF may be updated according to the estimated output signal EO_S and the previous far-end channel filter PFE_F (S2000). The current far-end channel filter CFE_F may be expressed as shown in [Equation 2].

In operation S3000, a result signal OUT_S calculated based on the current far-end channel filter CFE_F and the input signal IN_S may be provided.

The result signal OUT_S may be expressed as Equation 14 below.

[Equation 14]

In the updating of the current far-end channel filter CFE_F, the variance VAR may be estimated based on the estimated output signal EO_S (S2100). An inverse autocorrelation matrix (IACM) calculated based on the variance may be generated (S2300).

15 and 16 may be applied when the first wave-end signal or the second wave-end signal is zero in FIG. 1. In the present invention, only mono or stereo is described, but embodiments according to the present invention may be applied to three or more noise sources.

Claims

Providing a first estimated output signal calculated based on a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to the previous frame;

Updating a first current far-end channel filter corresponding to a current frame according to the first estimated output signal and the first previous far-end channel filter;

Providing a second estimated output signal calculated based on the first current far-end channel filter, the second previous far-end channel filter, and the input signal;

Updating a second current far-end channel filter corresponding to a current frame according to the second estimated output signal and the second previous far-end channel filter; And

And providing a result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal.
The method of claim 1,

Providing the first estimated output signal,

Calculating a first correlation coefficient or power ratio based on the first previous wave-end channel filter and the second previous wave-end channel filter; And

And calculating the first estimated output signal according to the first correlation coefficient or power ratio.
The method of claim 2,

The updating of the first current far-end channel filter may include:

Estimating a first variance based on the first estimated output signal;

Generating a first correlation vector matrix calculated based on the first variance; And

And calculating a first forgetting factor based on the first estimated output signal.
The method of claim 3,

And wherein the first variance is determined by the first estimated output signal provided based on the first previous far-end channel filter and the second previous far-end channel filter.
The method of claim 1,

Providing the second estimated output signal includes:

Calculating a second correlation coefficient or power ratio based on the first current far-end channel filter and the second previous wave-end channel filter; And

And calculating the second estimated output signal according to the second correlation coefficient or power ratio.
The method of claim 5,

The updating of the second current far-end channel filter may include:

Estimating two variances based on the second estimated output signal;

Generating a second correlation vector matrix calculated based on the second variance; And

And calculating a second forgetting factor based on the second estimated output signal.
The method of claim 6,

And wherein the second variance is determined by the second estimated output signal provided based on the first current far-end channel filter and the second previous far-end channel filter.
The method of claim 1,

Providing the result signal,

Calculating a third correlation coefficient or power ratio based on the first current far-end channel filter and the second current far-end channel filter; And

And calculating the resultant signal according to the third correlation coefficient or power ratio.
Setting an initial value;

Providing a first estimated output signal calculated based on a first previous far-end channel filter corresponding to a previous frame, a second previous far-end channel filter, and an input signal, wherein the first estimated output signal Updating a first current far-end channel filter corresponding to a current frame according to the first previous far-end channel filter;

Providing a second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal, wherein the second estimated output signal and the second previous wave- Updating a second current far-end channel filter corresponding to the current frame according to the end channel filter; And

And providing a resultant signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal.
The method of claim 9,

The updating of the first current far-end channel filter may include:

Calculating a first correlation coefficient or power ratio based on the first previous wave-end channel filter and the second previous wave-end channel filter;

Calculating the first estimated output signal according to the first correlation coefficient or power ratio;

Estimating a first variance of the first estimated output signal; And

And generating a first inverse autocorrelation matrix calculated based on the first variance.
The method of claim 9,

The updating of the second current far-end channel filter may include:

Calculating a second correlation coefficient or power ratio based on the first current far-end channel filter and the second previous wave-end channel filter;

Calculating the second estimated output signal according to the second correlation coefficient or power ratio;

Estimating a second variance of the second estimated output signal; And

Generating a second inverse autocorrelation matrix calculated based on the second variance.
A first estimator providing a first estimated output signal calculated based on a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to the previous frame;

A first filter unit to update a first current far-end channel filter corresponding to a current frame according to the first estimated output signal and the first previous far-end channel filter;

A second estimator for providing a second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal;

A second filter unit for updating a second current far-end channel filter corresponding to a current frame according to the second estimated output signal and the second previous far-end channel filter; And

And an output unit configured to provide a result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal.
The method of claim 12,

And calculating the first estimated output signal according to a first correlation coefficient or a power ratio calculated based on the first previous wave-end channel filter and the second previous wave-end channel filter.
An initialization unit for setting an initial value;

A first estimator providing a first estimated output signal calculated based on a first previous far-end channel filter, a second previous far-end channel filter, and an input signal corresponding to the previous frame;

A first filter unit to update a first current far-end channel filter corresponding to a current frame according to the first estimated output signal and the first previous far-end channel filter;

A second estimator for providing a second estimated output signal calculated based on the first current far-end channel filter, the second previous wave-end channel filter, and the input signal;

A second filter unit for updating a second current far-end channel filter corresponding to a current frame according to the second estimated output signal and the second previous far-end channel filter; And

And an output unit configured to provide a result signal calculated based on the first current far-end channel filter, the second current far-end channel filter, and the input signal.
The method of claim 14,

And the second estimated output signal is calculated according to a second correlation coefficient or a power ratio calculated based on the first current far-end channel filter and the second previous wave-end channel filter. .
Providing an estimated output signal calculated based on a previous far-end channel filter and an input signal corresponding to the previous frame;

Updating a current far-end channel filter corresponding to a current frame according to the estimated output signal and the previous far-end channel filter; And

And providing a resultant signal calculated based on the current far-end channel filter and the input signal.
The method of claim 16,

Updating the current far-end channel filter,

Estimating variance based on the estimated output signal; And

Generating an inverse autocorrelation matrix calculated on the basis of the variance.
The method of claim 3,

And the first forgetting factor has a constant value or is determined by the first estimated output signal.
The method of claim 6,

The second forgetting factor has a constant value or is determined by the second estimated output signal.