CN113971958A - Method and device for eliminating echo, audio and video terminal and conference terminal - Google Patents

Abstract

The embodiment of the application removes the estimated echo signal from the microphone signal collected by the call microphone through adaptive filtering processing by two stages of adaptive filtering processing, namely, the first stage takes a far-end signal as a reference signal, so that the effect of linear elimination is achieved; and in the second stage, the collected signal collected by the microphone and played by the loudspeaker is used as a reference signal, and the nonlinear distortion signal is subtracted from the microphone signal collected by the call microphone through nonlinear adaptive filtering processing, so that the nonlinear elimination effect is achieved. The device for eliminating the echo improves the problem of performance degradation caused by nonlinear distortion to echo elimination, and well improves the call quality.

Description

A method and device for eliminating echo, audio and video terminal and conference terminal

technical field

The present application relates to, but is not limited to, the field of electronic technology, and more particularly, to a method and apparatus for eliminating echo, an audio-video terminal, and a conference terminal.

Background technique

In the call scenario, the far-end voice signal is transmitted to the near-end device through the network, and will be played through the speaker, and the microphone will pick up the sound played by the speaker (this part of the sound is called the echo signal), so that the echo signal is transmitted back to the The far-end device allows the far-end user to hear their own voice from the speaker, which greatly reduces the call quality.

In the related art, in order to cancel the echo, the far-end voice signal for sending to the speaker is used as a reference signal during the communication process, and the echo of the near-end voice signal is canceled.

Due to the poor design of the loudspeaker and acoustic structure, nonlinear distortion is easily generated when the device plays the voice signal, and such nonlinear distortion signal picked up by the microphone is not included in the far-end signal used as the reference signal. That is to say, the related art The echo cancellation scheme in , cannot process this part of the interference signal, and the nonlinear components will remain, thus affecting the call quality.

SUMMARY OF THE INVENTION

The present application provides a method and device for eliminating echo, an audio and video terminal, and a conference terminal, which can improve call quality.

An embodiment of the present invention provides an echo cancellation device, including: a speaker, a microphone for a call, a microphone for collection, a first processing module, and a second processing module; wherein,

The loudspeaker is set to receive and play the far-end voice signal from the far-end to generate an echo signal;

Collect the microphone, and set it to collect the signal played by the speaker to obtain the collected signal;

The call microphone is set to pick up the echo signal, the near-end vocal signal and the noise signal to obtain the microphone signal;

a first processing module, configured to perform adaptive filtering processing on the microphone signal according to the far-end voice signal;

The second processing module is configured to perform nonlinear adaptive filtering processing on the intermediate signal after the adaptive filtering processing according to the collected signal, so as to generate a voice signal after echo cancellation.

In an exemplary example, the first processing module includes: an adaptive filter, a first stacker; wherein,

an adaptive filter, configured to calculate the inputted far-end voice signal to obtain a first analog echo signal;

The first superimator is configured to perform superposition processing on the microphone signal and the first analog echo signal to obtain an intermediate signal.

In an exemplary example, the second processing module includes: a nonlinear adaptive filter, a second stacker; wherein,

a nonlinear adaptive filter, configured to calculate the inputted collected signal to obtain a second analog echo signal;

The second stacker is configured to perform superposition processing on the intermediate signal and the second analog echo signal to obtain the voice signal.

In an illustrative example, the acquisition microphone is located anywhere near the speaker.

Embodiments of the present application further provide an audio and video terminal, including the echo cancellation apparatus described in any one of the above.

The embodiment of the present application further provides a method for eliminating echo, including:

Generate an echo signal according to the far-end voice signal;

Acquire the echo signal, near-end vocal signal and noise signal picked up by the call microphone to obtain the microphone signal;

Adaptive filtering is performed on the microphone signal according to the far-end voice signal to achieve linear echo cancellation;

Obtain the acquisition signal played by the acquisition speaker collected by the acquisition microphone;

According to the acquired signal, nonlinear adaptive filtering is performed on the signal processed by the adaptive filtering to generate a voice signal after echo cancellation, so as to realize nonlinear echo cancellation.

In an exemplary example, the adaptive filtering processing on the microphone signal according to the far-end speech signal includes:

Adaptive filtering is performed on the far-end speech signal to obtain a first analog echo signal;

The microphone signal and the first analog echo signal are superimposed to obtain an intermediate signal.

In an exemplary example, performing nonlinear adaptive filtering processing on the signal after adaptive filtering according to the acquired signal includes:

Performing nonlinear adaptive filtering calculation on the collected signal to obtain a second analog echo signal;

The voice signal is obtained by superimposing the intermediate signal and the second analog echo signal.

Embodiments of the present application further provide a computer-readable storage medium storing computer-executable instructions, where the computer-executable instructions are used to execute any of the echo cancellation methods described above.

An embodiment of the present application further provides an echo cancellation device, including a memory and a processor, wherein the memory stores the following instructions executable by the processor: for executing the steps of the echo cancellation method described in any of the above .

The embodiment of the present application also provides a method for eliminating nonlinear echo, including:

Perform adaptive filtering processing on the microphone signal according to the far-end voice signal;

According to the collected signal played by the collected loudspeaker, nonlinear adaptive filtering is performed on the signal after adaptive filtering to generate a voice signal after echo cancellation.

In an exemplary example, the adaptive filtering process on the microphone signal includes:

Adaptive filtering is performed on the far-end speech signal to obtain a first analog echo signal;

The microphone signal and the first analog echo signal are superimposed to obtain an intermediate signal.

In an exemplary example, performing nonlinear adaptive filtering processing on the signal after adaptive filtering includes:

Performing nonlinear adaptive filtering calculation on the collected signal to obtain a second analog echo signal;

The voice signal is obtained by superimposing the intermediate signal and the second analog echo signal.

In an exemplary example, before performing the nonlinear adaptive filtering processing on the signal processed by the adaptive filtering, the method further includes:

The acquisition signal is acquired by a acquisition microphone disposed close to the speaker.

An embodiment of the present application provides a conference terminal, including: a speaker, a microphone for a call, a microphone for acquisition, an adaptive filter, a nonlinear adaptive filter, a first superimposed, and a second superimposed; wherein,

A loudspeaker, set to play the far-end voice signal from the far-end conference terminal;

The call microphone is set to pick up the echo signal, the near-end vocal signal and the noise signal to obtain the microphone signal;

an adaptive filter, configured to calculate the input far-end voice signal to obtain a first analog echo signal;

a first stacker, configured to perform stacking processing on the microphone signal and the first analog echo signal to obtain an intermediate signal;

Collect the microphone, set it to collect the signal played by the speaker, and obtain the collected signal;

The nonlinear adaptive filter is set to calculate the input acquisition signal to obtain the second analog echo signal;

The second stacker is configured to perform stacking processing on the intermediate signal and the second analog echo signal to obtain a speech signal.

The embodiment of the present application effectively implements echo cancellation through two-stage adaptive filtering processing: the first stage includes: taking the far-end signal as a reference signal, and removing the estimated value from the microphone signal collected by the talking microphone through adaptive filtering processing The echo signal achieves the effect of linear cancellation; the second stage includes: taking the acquisition signal played by the speaker collected by the acquisition microphone as the reference signal, and subtracting the estimated value from the microphone signal acquired by the call microphone through nonlinear adaptive filtering processing The obtained nonlinear distortion signal achieves the effect of nonlinear elimination. The apparatus for eliminating echo of the present application improves the problem of performance degradation caused by nonlinear distortion in echo cancellation, and greatly improves call quality.

Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the description, claims and drawings.

Description of drawings

The accompanying drawings are used to provide a further understanding of the technical solutions of the present application, and constitute a part of the specification. They are used to explain the technical solutions of the present application together with the embodiments of the present application, and do not constitute a limitation on the technical solutions of the present application.

1 is a schematic flowchart of a method for eliminating echo in the present application;

FIG. 2 is a schematic structural diagram of an embodiment of adaptive filtering processing of the present application;

FIG. 3 is a schematic structural diagram of an embodiment of nonlinear adaptive filtering processing of the present application;

FIG. 4 is a schematic diagram of the composition structure of the apparatus for eliminating echo of the present application;

FIG. 5 is a schematic structural diagram of an embodiment of the application for echo cancellation;

FIG. 6 is a schematic diagram of the composition and structure of an embodiment of a conference terminal of the present application.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be noted that, the embodiments in the present application and the features in the embodiments may be arbitrarily combined with each other if there is no conflict.

In a typical configuration of the present application, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

Memory may include non-persistent memory in computer readable media, random access memory (RAM) and/or non-volatile memory in the form of, for example, read only memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media includes both persistent and non-permanent, removable and non-removable media, and storage of information may be implemented by any method or technology. Information may be computer readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read only memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), Flash Memory or other memory technology, Compact Disc Read Only Memory (CD-ROM), Digital Versatile Disc (DVD) or other optical storage, Magnetic tape cartridges, magnetic tape disk storage or other magnetic storage devices or any other non-transmission medium that can be used to store information that can be accessed by a computing device. Computer-readable media, as defined herein, excludes non-transitory computer-readable media, such as modulated data signals and carrier waves.

The steps shown in the flowcharts of the figures may be performed in a computer system, such as a set of computer-executable instructions. Also, although a logical order is shown in the flowcharts, in some cases the steps shown or described may be performed in an order different from that herein.

FIG. 1 is a schematic flowchart of the method for eliminating echo of the present application, as shown in FIG. 1 , including:

Step 100: Perform adaptive filtering processing on the microphone signal according to the far-end speech signal.

In an illustrative example, this step may include:

Adaptive filtering is performed on the far-end speech signal to obtain a first analog echo signal;

Superimpose the microphone signal and the first analog echo signal to obtain an intermediate signal.

FIG. 2 is a schematic structural diagram of an embodiment of adaptive filtering processing of the present application. As shown in FIG. 2, the far-end voice signal x(n) is the signal transmitted from the far-end device to the near-end device through the network; the microphone signal y( n) is the signal of the near-end input call microphone, the microphone signal y(n) includes the near-end human voice signal, echo signal, noise signal, etc.; the far-end speech signal x(n) is input to the adaptive filter, after the adaptive filter The first analog echo signal is obtained by the calculation of , and the signal e(n) is the signal after adaptive filtering, and the signal e(n) is equal to the difference between the microphone signal y(n) and the first analog echo signal.

In the adaptive filtering process shown in Figure 2, the far-end signal is used as a reference signal to perform adaptive filtering processing with the microphone signal collected by the microphone to estimate the echo signal, and finally the estimated echo signal is subtracted from the microphone signal collected by the call microphone. The echo signal has achieved the effect of linear cancellation.

Step 101 : Perform nonlinear adaptive filtering processing on the signal after adaptive filtering according to the collected signal played by the collected speaker, to generate a voice signal after echo cancellation.

In an illustrative example, this step may include:

Performing nonlinear adaptive filtering calculation on the acquired signal to obtain a second analog echo signal;

A voice signal is obtained by superimposing the intermediate signal and the second analog echo signal.

FIG. 3 is a schematic structural diagram of an embodiment of nonlinear adaptive filtering processing of the present application. As shown in FIG. 3 , the signal e(n) is the signal after the adaptive filtering processing as shown in FIG. 2 ; the collected signal r(n) ) is the signal played by the loudspeaker that the acquisition microphone at any position close to the loudspeaker collects; the acquisition signal r(n) is input to a nonlinear adaptive filter, and the second analog echo signal is obtained through the calculation of the nonlinear adaptive filter; The signal e'(n) is the signal processed by nonlinear adaptive filtering, that is, the voice signal after echo cancellation, and the signal e'(n) is equal to the signal e(n) processed by the adaptive filtering and the second analog echo signal difference value.

If the loudspeaker generates nonlinear components, the signal e(n) after adaptive filtering as shown in FIG. 2 will have residual nonlinear distortion components. At this time, the acquisition microphone in the embodiment of the present application can The characteristic signal of the nonlinear component of the speaker is picked up, as shown in Figure 3, the acquisition signal collected by the acquisition microphone is used as the reference signal, and the adaptive filtering signal e(n) is processed by nonlinear adaptive filtering to estimate the non-linearity. Linear distortion signal, and finally the estimated nonlinear distortion signal is subtracted from the microphone signal collected by the call microphone to achieve the effect of nonlinear cancellation, which improves the performance degradation caused by nonlinear distortion to echo cancellation, better improved call quality.

The method for eliminating echo of the present application uses two-stage adaptive filtering processing, that is, first, taking the far-end signal as a reference signal, and removing the estimated echo signal from the microphone signal collected by the talking microphone through adaptive filtering processing to achieve linearity. Then, the acquisition signal played by the speaker collected by the acquisition microphone is used as the reference signal, and the estimated nonlinear distortion signal is subtracted from the microphone signal collected by the call microphone through nonlinear adaptive filtering processing. The effect of nonlinear elimination. The method for eliminating echo of the present application improves the problem of performance degradation caused by nonlinear distortion in echo cancellation, and greatly improves call quality.

The present application also provides a computer-readable storage medium storing computer-executable instructions, where the computer-executable instructions are used to execute any one of the echo cancellation methods described above.

The present application further provides an echo canceling device, including a memory and a processor, wherein the memory stores the following instructions executable by the processor: for executing the steps of the echo canceling method described in any one of the above.

The application also provides a method for eliminating echo, including:

Generate an echo signal according to the far-end voice signal;

Acquire the echo signal, near-end vocal signal and noise signal picked up by the call microphone to obtain the microphone signal;

Adaptive filtering is performed on the microphone signal according to the far-end voice signal to achieve linear echo cancellation;

Obtain the acquisition signal played by the acquisition speaker collected by the acquisition microphone;

Non-linear adaptive filtering is performed on the intermediate signal after adaptive filtering according to the acquired signal to generate a voice signal after echo cancellation, so as to realize nonlinear echo cancellation.

In an exemplary example, adaptive filtering processing is performed on the microphone signal according to the far-end speech signal, including:

Adaptive filtering is performed on the far-end speech signal to obtain a first analog echo signal;

The microphone signal and the first analog echo signal are superimposed to obtain an intermediate signal.

In an exemplary example, performing nonlinear adaptive filtering processing on the adaptive filtering signal according to the acquired signal, including:

Performing nonlinear adaptive filtering calculation on the collected signal to obtain a second analog echo signal;

The voice signal is obtained by superimposing the intermediate signal and the second analog echo signal.

FIG. 4 is a schematic structural diagram of the apparatus for eliminating echo of the present application. As shown in FIG. 4 , it at least includes: a speaker, a talking microphone, a collecting microphone, a first processing module, and a second processing module; wherein,

The loudspeaker is set to receive and play the far-end voice signal from the far-end to generate an echo signal;

Collect the microphone, and set it to collect the signal played by the speaker to obtain the collected signal;

The call microphone is set to pick up the echo signal, the near-end vocal signal and the noise signal to obtain the microphone signal;

a first processing module, configured to perform adaptive filtering processing on the microphone signal according to the far-end voice signal;

The second processing module is configured to perform nonlinear adaptive filtering processing on the intermediate signal processed by the adaptive filtering according to the acquired acquisition signal, so as to generate a voice signal after echo cancellation.

In one illustrative example, the acquisition microphone is positioned anywhere near the speaker. That is, the distance between the speaker and the acquisition microphone is smaller than the distance between the speaker and the call microphone.

In an exemplary example, as shown in FIG. 2 , the first processing module may include: an adaptive filter, a first stacker; wherein,

an adaptive filter, configured to calculate the input far-end voice signal to obtain a first analog echo signal;

The first stacker is configured to perform stacking processing on the microphone signal and the first analog echo signal to obtain an intermediate signal.

In an exemplary example, as shown in FIG. 3 , the second processing module may include: a nonlinear adaptive filter, a second stacker; wherein,

The nonlinear adaptive filter is set to calculate the input acquisition signal to obtain the second analog echo signal;

The second stacker is configured to perform stacking processing on the intermediate signal and the second analog echo signal to obtain a speech signal.

The apparatus for eliminating echo of the present application uses two-stage adaptive filtering processing, that is, the first stage includes: taking the far-end signal as a reference signal, and removing the estimated echo signal from the microphone signal collected by the talking microphone through adaptive filtering processing, The effect of linear cancellation is achieved; the second stage includes: taking the acquisition signal played by the speaker collected by the acquisition microphone as the reference signal, and subtracting the estimated non-linear signal from the microphone signal acquired by the call microphone through nonlinear adaptive filtering processing. Linear distortion signal, to achieve the effect of nonlinear elimination. The apparatus for eliminating echo of the present application improves the problem of performance degradation caused by nonlinear distortion in echo cancellation, and greatly improves call quality.

FIG. 5 is a schematic structural diagram of an embodiment of the apparatus for eliminating echoes of the present application. As shown in FIG. 5 , in this embodiment, the far-end voice signal x(n) is input to the speaker of the near-end device to generate an echo signal, and the echo signal and the near-end device generate an echo signal. The end human voice signal and noise signal are collected by the call microphone of the near-end device, and the microphone signal y(n) is obtained. At the same time, the far-end voice signal x(n) is input to the adaptive filter, and the first The analog echo signal x'(n); after the microphone signal y(n) is superimposed with the first analog echo signal x ^' (n), the intermediate signal e(n) minus the estimated echo signal is obtained; The acquisition microphone picks up the nonlinear echo signal played by the speaker, that is, the acquisition signal r(n), the acquisition signal r(n) is input to the nonlinear adaptive filter, and the second analog echo signal r' is obtained through the calculation of the nonlinear adaptive filter. (n): After the intermediate signal e(n) and the second analog echo signal r'(n) are superimposed, a speech signal e'(n) obtained by subtracting the nonlinear echo signal is obtained. Through this embodiment, the problem of performance degradation caused by nonlinear distortion to echo cancellation is improved, and the call quality is well improved.

The embodiment of the present application further provides an audio and video terminal, including any one of the echo cancellation apparatuses shown in FIG. 4 of the present application.

An embodiment of the present application further provides a conference terminal. FIG. 6 is a schematic structural diagram of an embodiment of the conference terminal of the present application. As shown in FIG. 6 , the conference terminal at least includes: a speaker, a microphone for a call, a collection microphone, an adaptive filter, a a nonlinear adaptive filter, a first stacker, and a second stacker; wherein,

A loudspeaker, set to play the far-end voice signal from the far-end conference terminal;

The call microphone is set to pick up the echo signal, the near-end vocal signal and the noise signal to obtain the microphone signal;

an adaptive filter, configured to calculate the input far-end voice signal to obtain a first analog echo signal;

a first stacker, configured to perform stacking processing on the microphone signal and the first analog echo signal to obtain an intermediate signal;

Collect the microphone, set it to collect the signal played by the speaker, and obtain the collected signal;

The nonlinear adaptive filter is set to calculate the input acquisition signal to obtain the second analog echo signal;

The second stacker is configured to perform stacking processing on the intermediate signal and the second analog echo signal to obtain a speech signal.

In one illustrative example, the acquisition microphone is located anywhere near the speaker.

The conference terminal of the present application undergoes two-stage adaptive filtering processing, that is, the first stage includes: taking the far-end signal as a reference signal, and removing the estimated echo signal from the microphone signal collected by the talking microphone through adaptive filtering processing, to achieve The effect of linear cancellation; the second stage includes: taking the acquisition signal played by the speaker collected by the acquisition microphone as a reference signal, and subtracting the estimated nonlinear distortion from the microphone signal acquired by the call microphone through nonlinear adaptive filtering processing signal to achieve the effect of non-linear cancellation. Through the conference terminal of the present application, the problem of performance degradation caused by nonlinear distortion to echo cancellation is improved, and the quality of conference calls is well improved.

Although the embodiments disclosed in the present application are as above, the described contents are only the embodiments adopted to facilitate the understanding of the present application, and are not intended to limit the present application. Any person skilled in the art to which this application belongs, without departing from the spirit and scope disclosed in this application, can make any modifications and changes in the form and details of the implementation, but the scope of patent protection of this application must still be The scope defined by the appended claims shall prevail.

Claims (15)

1. A device for eliminating echoes, comprising: a speaker, a call microphone, a collection microphone, a first processing module, and a second processing module; wherein, The loudspeaker is set to receive and play the far-end voice signal from the far-end to generate an echo signal; Collect the microphone, and set it to collect the signal played by the speaker to obtain the collected signal; The call microphone is set to pick up the echo signal, the near-end vocal signal and the noise signal to obtain the microphone signal; a first processing module, configured to perform adaptive filtering processing on the microphone signal according to the far-end voice signal; The second processing module is configured to perform nonlinear adaptive filtering processing on the intermediate signal after the adaptive filtering processing according to the collected signal, so as to generate a voice signal after echo cancellation. 2. The apparatus of claim 1, wherein the first processing module comprises: an adaptive filter, a first stacker; wherein, an adaptive filter, configured to calculate the inputted far-end voice signal to obtain a first analog echo signal; The first superimator is configured to perform superposition processing on the microphone signal and the first analog echo signal to obtain an intermediate signal. 3. The apparatus according to claim 2, wherein the second processing module comprises: a nonlinear adaptive filter, a second stacker; wherein, a nonlinear adaptive filter, configured to calculate the inputted collected signal to obtain a second analog echo signal; The second stacker is configured to perform superposition processing on the intermediate signal and the second analog echo signal to obtain the voice signal. 4. The apparatus according to any one of claims 1 to 3, wherein the acquisition microphone is arranged at any position close to the speaker. 5. An audio and video terminal, comprising the echo cancellation device according to any one of claims 1 to 3. 6. A method of eliminating echo, comprising: Generate an echo signal according to the far-end voice signal; Acquire the echo signal, near-end vocal signal and noise signal picked up by the call microphone to obtain the microphone signal; Adaptive filtering is performed on the microphone signal according to the far-end voice signal to achieve linear echo cancellation; Obtain the acquisition signal played by the acquisition speaker collected by the acquisition microphone; According to the acquired signal, nonlinear adaptive filtering is performed on the signal processed by the adaptive filtering to generate a voice signal after echo cancellation, so as to realize nonlinear echo cancellation. 7. The method according to claim 6, wherein the adaptive filtering processing on the microphone signal according to the far-end speech signal comprises: Adaptive filtering is performed on the far-end speech signal to obtain a first analog echo signal; The microphone signal and the first analog echo signal are superimposed to obtain an intermediate signal. 8. The method according to claim 7, wherein, performing nonlinear adaptive filtering processing on the signal after adaptive filtering according to the acquired signal, comprising: Performing nonlinear adaptive filtering calculation on the collected signal to obtain a second analog echo signal; The voice signal is obtained by superimposing the intermediate signal and the second analog echo signal. 9. A method of eliminating nonlinear echo, comprising: Perform adaptive filtering processing on the microphone signal according to the far-end voice signal; According to the collected signal played by the collected loudspeaker, nonlinear adaptive filtering is performed on the signal after adaptive filtering to generate a voice signal after echo cancellation. 10. The method according to claim 9, wherein the adaptive filtering processing on the microphone signal comprises: Adaptive filtering is performed on the far-end speech signal to obtain a first analog echo signal; The microphone signal and the first analog echo signal are superimposed to obtain an intermediate signal. 11. The method according to claim 10, wherein the performing nonlinear adaptive filtering processing on the signal processed by the adaptive filtering comprises: Performing nonlinear adaptive filtering calculation on the collected signal to obtain a second analog echo signal; The voice signal is obtained by superimposing the intermediate signal and the second analog echo signal. 12. The method according to any one of claims 9 to 11, before performing the nonlinear adaptive filtering processing on the signal processed by the adaptive filtering, further comprising: The acquisition signal is acquired by a acquisition microphone disposed close to the speaker. 13 . A computer-readable storage medium storing computer-executable instructions, the computer-executable instructions being used to execute the echo cancellation method according to any one of claims 6 to 8 . 14. An echo cancellation device, comprising a memory and a processor, wherein the memory stores the following instructions executable by the processor: for executing the echo cancellation method according to any one of claims 6 to 8 A step of. 15. A conference terminal, comprising: a speaker, a call microphone, a collection microphone, an adaptive filter, a non-linear adaptive filter, a first stacker, and a second stacker; wherein, A loudspeaker, set to play the far-end voice signal from the far-end conference terminal; The call microphone is set to pick up the echo signal, the near-end vocal signal and the noise signal to obtain the microphone signal; an adaptive filter, configured to calculate the input far-end voice signal to obtain a first analog echo signal; a first stacker, configured to perform stacking processing on the microphone signal and the first analog echo signal to obtain an intermediate signal; Collect the microphone, set it to collect the signal played by the speaker, and obtain the collected signal; The nonlinear adaptive filter is set to calculate the input acquisition signal to obtain the second analog echo signal; The second stacker is configured to perform stacking processing on the intermediate signal and the second analog echo signal to obtain a speech signal.

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