Active noise reduction method and system for earphone and noise reduction earphone

Abstract

The invention relates to an active noise reduction method and system for an earphone and a noise reduction earphone, the earphone comprises a feed-forward microphone, a feedback microphone and a loudspeaker, the earphone also comprises a plurality of filter banks, and the active noise reduction method comprises the following steps: obtaining a first noise signal currently collected by the feed-forward microphone; acquiring a reverse signal played through a loudspeaker; calculating a first transfer function of the secondary channel; and based on the first transfer function, the second transfer function and the frequency response parameters of the plurality of filter banks with different ANC parameter configurations, noise reduction residual volume curves corresponding to the filter banks are calculated, and based on the noise reduction residual volume curves, the matched filter banks are selected. Therefore, the matched filter bank can be selected without playing a prompt tone or a special signal and traversing each filter bank, the matching process time is short, and the subjective experience of user use is improved.

Description

Technical Field

[0001] This application relates to the technical field of active noise-canceling headphones. More specifically, it relates to an active noise-canceling method, system, and noise-canceling headphones for headphones. Background Art

[0002] With the development of technology, ANC (active noise cancellation) has been widely applied. However, when ANC is used in headphones, due to differences in the ear canals of users, the actual noise-canceling effects of different users will vary, and different ways of wearing headphones by users will also lead to differences in the actual noise-canceling effects. To address this issue, a commonly used method in the industry is to measure the secondary channel by playing a prompt tone or a special signal (such as white noise or pink noise), that is, to play a prompt tone or a special signal using the headphone speaker, collect the signal by the feedback microphone inside the headphone, then calculate the secondary channel transfer function based on the speaker signal and the signal collected by the feedback microphone, and then select the corresponding optimal target filter coefficients according to the calculated secondary channel transfer function.

[0003] However, in the design of the UI (user interface) of some products, the function of playing a prompt tone is not provided. Therefore, the method of playing a prompt tone or a special signal cannot be used for active noise cancellation. In this case, another alternative method is the method of traversing filter coefficients, that is, first select mode 0, and configure the filter coefficients corresponding to mode 0 into the filter bank hardware, and then calculate the noise reduction amount based on the signals collected by the feedforward microphone and the feedback microphone. In this way, traverse each mode, repeat the above steps, and finally determine the parameter configuration of the filter bank based on the noise reduction amounts in each mode. However, the method of traversing filter coefficients will cause the user's listening experience to change repeatedly. Especially when there are many filter banks, the test time is often long, and the subjective experience of the user is not good.

[0004] It can be seen that in the prior art, no active noise-canceling method has been found that can quickly and accurately configure the filter bank, thereby making the user experience better. Summary of the Invention

[0005] This application is provided to solve the above-mentioned defects existing in the prior art. There is a need for an active noise-canceling method, system, and noise-canceling headphones for headphones that can obtain the noise reduction conditions of each filter bank without playing a prompt tone or a special signal and without traversing the coefficients of each filter bank, complete the test in a short time, prevent the user's listening experience from changing repeatedly, improve the headphone usage experience, and can also accurately match and obtain the ANC (active noise cancellation) parameters suitable for the current wearing method and / or ear canal, eliminating the differences in noise-canceling effects caused by different ear canals and / or wearing methods.

[0006] According to a first aspect of the present application, there is provided an active noise cancellation method for an earphone. The earphone includes a feedforward microphone, a feedback microphone, and a speaker. The earphone further includes a plurality of filter banks. The active noise cancellation method includes the following steps: when the active noise cancellation function of the earphone is turned on, acquiring a first noise signal currently collected by the feedforward microphone; acquiring a reverse signal played through the speaker, where the reverse signal is obtained by filtering the first noise signal by a current filter bank; calculating a first transfer function of a secondary channel based on the first noise signal, a second transfer function of a primary channel, the reverse signal, and a second noise signal detected by the feedback microphone; calculating noise residue curves corresponding to each filter bank based on the first transfer function of the secondary channel, the second transfer function of the primary channel, and frequency response parameters of a plurality of filter banks with different ANC parameter configurations, and selecting a matching filter bank based on each noise residue curve, and configuring the current filter bank with the ANC parameters corresponding to the matching filter bank.

[0007] According to a second aspect of the present application, there is provided an active noise cancellation system for an earphone. The earphone includes a feedforward microphone, a feedback microphone, and a speaker. The active noise cancellation system further includes a processor and a plurality of filter banks. The processor is configured to be connected to the feedforward microphone, the feedback microphone, the speaker, and each filter bank respectively, and is used to execute the active noise cancellation method according to any embodiment of the present application.

[0008] According to a third aspect of the present application, there is provided a noise-canceling earphone, characterized in that the noise-canceling earphone includes a feedforward microphone, a feedback microphone, a speaker, and the active noise cancellation system according to any embodiment of the present application.

[0009] For an active noise cancellation method, system, and noise-canceling earphone for an earphone provided by various embodiments of the present application, after the environmental noise signal and the reverse signal are fused at the position of the feedback microphone, the feedback microphone detects a second noise signal. Based on the second transfer function of the primary channel, the first transfer function of the secondary channel, and the frequency response parameters of a plurality of filter banks with different ANC parameter configurations, noise residue curves corresponding to each filter bank for active noise cancellation are obtained. Then, a filter bank is selected according to the situation of the noise residue curves. In this way, it is not necessary to set the filter coefficients of each filter bank in the hardware to traverse each filter bank, which will not bring the user an experience of repeated changes in the listening feeling, and the time to match a suitable filter bank is short; selecting a filter bank according to the noise residue curve of active noise cancellation can more accurately match a filter bank suitable for the current wearing mode or ear canal characteristics and the corresponding ANC parameters, so that the re-matched earphone can obtain a good noise cancellation effect. Description of the Drawings

[0010] In the accompanying drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. The same reference numerals with alphabetical suffixes or different alphabetical suffixes may represent different instances of similar components. The drawings generally illustrate various embodiments by way of example and not limitation, and are used in conjunction with the description and the claims to explain the embodiments claimed. Where appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be an exhaustive or exclusive embodiment of the apparatus or method.

[0011] Figure 1 A related signal schematic diagram of a headset according to an embodiment of the present application is shown;

[0012] Figure 2 A flowchart of an active noise reduction method for a headset according to an embodiment of the present application is shown;

[0013] Figure 3 A schematic structural diagram of an active noise reduction system according to an embodiment of the present application is shown; and

[0014] Figure 4 A schematic structural diagram of a noise reduction headset according to an embodiment of the present application is shown. Detailed Embodiments

[0015] To enable those skilled in the art to better understand the technical solutions of the present application, the present application will be described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings and specific examples, but this is not a limitation of the present application.

[0016] The "first", "second" and similar terms used in the present application do not denote any order, quantity or importance, but are only used for distinction. Terms such as "comprising" or "including" mean that the elements before the term cover the elements listed after the term, and do not exclude the possibility of also covering other elements.

[0017] According to an embodiment of the present application, an active noise reduction method for a headset is provided. Figure 1A schematic diagram of relevant signals of a headset according to an embodiment of the present application is shown. The headset includes a feedforward microphone 101, a feedback microphone 102, and a speaker 103. The headset further includes a plurality of filter banks 104. Ambient noise 105 reaches the position of the feedforward microphone 101, so that the feedforward microphone 101 collects a first noise signal 106. The filter bank 104 receives the first noise signal 106 sent by the feedforward microphone 101. The filter bank 104 is communicatively connected to the speaker 103, so that the speaker 103 plays a reverse signal 107. The ambient noise 105 reaches the position of the feedback microphone through the primary channel 108, and the reverse signal 107 reaches the position of the feedback microphone 102 through the secondary channel 109 and overlaps at the position of the feedback microphone 102, so that the feedback microphone 102 collects a second noise signal 110. Each of the filter banks 104 has the same or different ANC parameters.

[0018] Figure 2 A flowchart of an active noise cancellation method for a headset according to an embodiment of the present application is shown. When the active noise cancellation function of the headset is turned on, in step 201, the first noise signal 106 currently collected by the feedforward microphone 101 is obtained. In step 202, the reverse signal 107 played by the speaker 103 is obtained, and the reverse signal 107 is obtained by filtering the first noise signal 106 by the current filter bank 104. Wherein, the current filter bank 104 can be any one of the plurality of filter banks 104.

[0019] In step 203, based on the first noise signal 106, the second transfer function of the primary channel 108, the reverse signal 107, and the second noise signal 110 detected by the feedback microphone 102, the first transfer function of the secondary channel 109 is calculated. Since the ambient noise 105 and the reverse signal 107 reach the position of the feedback microphone 102 through the primary channel and the secondary channel 109 respectively and overlap, so that the feedback microphone 102 detects the second noise signal 110, therefore, by reverse derivation from the second noise signal 110, the first transfer function of the secondary channel 109 can be obtained.

[0020] In step 204, based on the first transfer function of the secondary channel 109, the second transfer function of the primary channel 108, and the frequency response parameters of multiple filter banks 104 with different ANC parameter configurations, the noise residue curves corresponding to each filter bank 104 are calculated. Based on each noise residue curve, a matching filter bank 104 is selected, and the current filter bank 104 is configured using the ANC parameters corresponding to the matching filter bank 104. The frequency response is the relationship between the frequency of the ambient noise 105 that the filter bank 104 itself has and the gain. Therefore, the relationship between the first noise signal 106 and the reverse signal 107 corresponds to the frequency response of the filter bank 104. According to the signal energy of the first noise signal 106 and the signal energy of the second noise signal 110 detected by the feedback microphone 102, the noise residue of the active noise cancellation of the current filter bank 104 can be obtained. Based on this derivation, the relationship between the noise residue of the active noise cancellation of the current filter bank 104, the frequency response parameters, the first transfer function, and the second transfer function of the current filter bank 104 can be obtained. The ordinate of the noise residue curve is the noise residue, and the abscissa is the frequency of the ambient noise 105. The relationship between the noise residue and the corresponding frequency response parameters, the first transfer function, and the second transfer function can be applied to different filter banks 104 and different ear canals and / or wearing methods. Under the same ear canal and / or the same wearing method, the same first transfer function and second transfer function can be corresponding. Different filter banks 104 correspond to different frequency response parameters, and the noise residue curves of the active noise cancellation of each filter bank 104 can be obtained under the same ear canal and / or wearing method. The filter banks 104 with different ANC parameter configurations respectively have different noise residue curves, and thus a matching filter bank 104 is selected.

[0021] According to the noise residue curves of each filter bank 104, the noise residues of the active noise cancellation of each filter bank 104 can be compared, and the filter bank 104 with the minimum noise residue can be selected as the current filter bank 104. The current filter bank 104 can also be configured according to the ANC parameters corresponding to the filter bank 104 with the minimum noise residue, and then the appropriate filter bank and the corresponding ANC parameters can be accurately matched in the case of the current ear canal and / or wearing method.

[0022] Therefore, in the process of selecting the matching filter bank 104, only the first transfer function and the second transfer function need to be obtained by using the current filter bank 104, and there is no need to switch each filter bank 104 to repeat the test, which can avoid the repeated change of the user's auditory sense and improve the user's headphone usage experience. Active noise reduction can be performed without playing a prompt tone or a special signal, so it is applicable to both noise-canceling headphones with and without prompt tone playback. According to the relationship between the minimum noise residue and the frequency response parameters, the first transfer function and the second transfer function, the noise reduction situation of each filter bank 104 for the current ear canal and / or wearing mode can be obtained, so that the matching ANC parameters can be selected more specifically and accurately, and the optimal noise reduction effect on the current environmental noise 105 can be achieved.

[0023] Differences in the ear canal or different wearing modes of the headphones may result in different transmission paths for the primary channel 108 and the secondary channel 109, that is, the second transfer function and the first transfer function may be different. Therefore, when the first transfer function and the second transfer function change, the noise residue curves of each changed filter bank 104 can be obtained, and the filter bank 104 can be reselected for active noise reduction. Therefore, the active noise reduction method of the embodiment of the present application can eliminate the difference in the actual noise reduction effect brought about by different ear canals and / or wearing modes, so that users with different ear canal differences or in different wearing modes can all feel the optimal noise reduction effect.

[0024] In some embodiments, calculating the first transfer function of the secondary channel 109 based on the first noise signal 106, the second transfer function of the primary channel 108, the reverse signal 107, and the second noise signal 110 detected by the feedback microphone 102 specifically includes the following steps: obtaining the conduction signal of the primary channel 108 based on the first noise signal 106 and the second transfer function P(z); calculating the first transfer function S(z) based on the relationship that the second noise signal 110 is equal to the superposition of the conduction signals of the primary channel 108 and the secondary channel 109, where the conduction signal of the secondary channel 109 is obtained based on the reverse signal 107 and the first transfer function S(z).

[0025] Let \(D(z)\) be the energy of the signal that the environmental noise 105 arrives at the position of the feedback microphone 102 through the primary channel 108. \(D(z)\) can be expressed as the convolution of the signal energy \(X(z)\) of the first noise signal 106 and the second transfer function \(P(z)\), that is, \(D(z)=X(z)*P(z)\). The convolution of the signal energy \(Y(z)\) of the reverse signal 107 and the first transfer function \(S(z)\) can be expressed as \(Y(z)*S(z)\). \(Y(z)*S(z)\) is the energy of the signal that the reverse signal 107 arrives at the position of the feedback microphone 102 through the secondary channel 109. Therefore, after \(Y(z)*S(z)\) is superimposed with \(D(z)\), the signal energy \(E(z)\) of the second noise signal 110 is obtained, \(E(z)=X(z)*P(z)+Y(z)*S(z)\), where \(E(z)\), \(X(z)\) and \(Y(z)\) can all be directly obtained, and \(P(z)\) can be obtained by calculation, where \((z)\) represents frequency-domain conversion. Therefore, the first transfer function \(S(z)\) can be obtained. Further, the adaptive filtering algorithm, time-domain algorithm, frequency-domain algorithm or Z-domain algorithm, etc. can be used to calculate \(S(z)\) from \((E(z)-X(z)*P'(z)) / Y(z)\). Therefore, only the signals detected by the feedforward microphone 101, the feedback microphone 102, the current filter bank 104 and the speaker 103 are needed to obtain the first transfer function of the secondary channel 109 under the current ear canal and / or wearing mode.

[0026] In some embodiments, based on the first transfer function \(S(z)\) of the secondary channel 109, the second transfer function \(P(z)\) of the primary channel 108, and the frequency response parameters of multiple filter banks 104 with different ANC parameter configurations, calculating the noise residue curves of the active noise cancellation of each filter bank 104 specifically includes the following steps: based on the first transfer function \(S(z)\) of the secondary channel 109 and the second transfer function \(P(z)\) of the primary channel 108, obtaining the target transfer function in the case of the minimum noise residue; based on the target transfer function \(W_{opt}\) and the frequency response parameters of multiple filter banks 104 with different ANC parameter configurations, calculating the noise residue curves of each filter bank 104.

[0027] The case of the minimum noise residue is that the energy of the signal obtained by the reverse signal 107 passing through the secondary channel 109 to the position of the feedback microphone 102 and the signal of the ambient noise 105 passing through the primary channel 108 to the position of the feedback microphone 102 after superposition is 0 or close to 0. At this time, the noise reduction degree reaches the maximum, and thus the relationship between the target transfer function Wopt of the filter bank 104 in the case of the minimum noise residue and the first transfer function and the second transfer function can be obtained. Under different ear canals and / or wearing manners, there are corresponding first transfer function and second transfer function respectively, so different ear canals and wearing manners correspond to different Wopt respectively. Therefore, based on the relationship between Wopt and the frequency response parameters of each filter bank 104, the relationship between the minimum noise residue and different ear canals and / or wearing manners and the frequency response of each filter bank 104 can be reflected. Based on the current ear canal and / or wearing manner, and the frequency responses of different filter banks 104, a noise residue curve is obtained, and the filter bank 104 suitable for the current ear canal and / or wearing manner can be obtained.

[0028] In some embodiments, obtaining the target transfer function in the case of the optimal noise reduction amount based on the first transfer function S(z) of the secondary channel 109 and the second transfer function P(z) of the primary channel 108 specifically includes: calculating the target transfer function Wopt based on the relationship that the convolution of the target transfer function Wopt and the first transfer function S(z) is equal to the second transfer function P(z). In the case of the optimal noise reduction amount, the signal of the reverse signal 107 passing through the secondary channel 109 to the position of the feedback microphone and the signal of the ambient noise 105 passing through the primary channel 108 to the position of the feedback microphone are superposed, so that the feedback microphone 102 does not receive the noise signal. The relationship among the target transfer function Wopt, the first transfer function S(z) and the second transfer function P(z) can be expressed as P(z) = Wopt * S(z). Based on P(z) = Wopt * S(z), Wopt can be calculated by using an adaptive filtering algorithm, a time-domain algorithm, a frequency-domain algorithm or a Z-domain algorithm, etc. for P(z) / S(z). Therefore, for different ear canals and / or wearing manners of the earphones, the corresponding target transfer function Wopt can be obtained respectively.

[0029] In some embodiments, calculating the noise residue curves of each filter bank 104 based on the target transfer function and the frequency response parameters of multiple filter banks 104 with different ANC parameter configurations specifically includes: obtaining the noise residue curves of each filter bank 104 based on the target transfer function, the frequency response parameters of each filter bank 104 and Equation (1),

[0030] NR = 1 - Wff(z) / Wopt (1)

[0031] Where NR is the noise residue, Wff(z) is the frequency response parameter of the filter, and Wopt is the target transfer function.

[0032] Based on the first noise signal 106 and the second noise signal 110 detected by the feedback microphone 102, the noise residue can be obtained, that is, NR = E(z) / D(z). As described above, E(z) = X(z)*P(z) + Y(z)*S(z), so NR = (X(z)*P(z) + Y(z)*S(z)) / X(z)*P(z). Among them, the signal energy Y(z) of the reverse signal 107 is Y(z) = X(z)*Wff(z), so NR = (X(z)*P(z) - X(z)*Wff(z)*S(z)) / X(z)*P(z). After transformation, NR = 1 - Wff(z) / Wopt. In Equation (1), Wopt is the optimal target transfer function. In this way, the relationship between the noise residue, the target transfer function Wopt, and the frequency response parameter Wff(z) is obtained. Based on Equation (1), as long as Wopt under the current user and / or wearing method and Wff(z) of each filter bank 104 are obtained, the Wff(z) parameters of each filter bank 104 configured in the earphone can be directly obtained, and the noise residue curves of each filter bank 104 can be obtained relatively quickly, which is beneficial to shortening the time for matching the filter bank 104. Therefore, according to Equation (1), for different user wearings and / or wearing methods, it is possible to switch to the best noise reduction effect in a short time without traversing each filter bank 104, improving the user experience of using the earphone.

[0033] In some embodiments, the active noise reduction method further includes: based on the noise residue curve, selecting the average value of the noise residue of a single frequency band or the average value of the noise residues of multiple different frequency bands as the noise residue of the filter bank 104 to select a matching filter bank 104. The abscissa of the noise residue curve is the frequency of the ambient noise 105, and the ordinate is the noise residue. When comparing the noise residues of each filter bank 104, according to the situation of the ambient noise 105, for example, the average value of the noise residue of the single frequency band of 50 - 55 Hz can be selected for comparison, or the average value of the noise residues of two different frequency bands of 50 - 55 Hz and 100 - 120 Hz can be used for comparison. The average value can be a weighted average value, and the weights of each frequency band can be configured according to the situation of the ambient noise 105. In this way, the filter bank 104 that matches the ambient noise 5 can be selected more accurately, improving the noise reduction effect.

[0034] In some embodiments, the active noise cancellation method further includes: when the active noise cancellation function of the earphone is turned off, obtaining a second transfer function of the primary channel 108 based on the third noise signal collected by the feedforward microphone 101 and the fourth noise signal collected by the feedback microphone 102. When the active noise cancellation function is turned off and there is external ambient noise 105, the relationship between the signal energy F(z) of the fourth noise signal is obtained by performing a convolution operation on the signal energy T(z) of the third noise signal and the second transfer function, so that the second transfer function can be obtained. P(z) is obtained according to T(z)*P(z)=F(z).

[0035] In some embodiments, based on the third noise signal and the fourth noise signal, the second transfer function is obtained by using an adaptive filtering algorithm, a time-domain algorithm, a frequency-domain algorithm, a Z-domain algorithm, etc. As described above, T(z)*P(z)=F(z), and the result obtained by calculating F(z) / T(z) using the adaptive filtering algorithm is P(z).

[0036] According to an embodiment of the present application, an active noise cancellation system for an earphone is also provided. The earphone includes a feedforward microphone, a feedback microphone, and a speaker. The active noise cancellation system 300 further includes a processor 302 and a plurality of filter banks 104. The processor 302 is configured to be connected to the feedforward microphone, the feedback microphone, the speaker, and each filter bank 104 respectively, and is used to execute the active noise cancellation method described in any embodiment of the present application. Therefore, during the process of selecting a matching filter bank 104, the active noise cancellation system only needs to use the current filter bank 104 to obtain the first transfer function and the second transfer function, without switching each filter bank 104 to repeat the test, which can avoid the repeated change of the user's listening experience and improve the user's earphone usage experience. Active noise cancellation can be performed without playing a prompt tone or a special signal, so it is applicable to both noise-canceling earphones with and without prompt tone playback. According to the relationship between the minimum noise residue and the frequency response parameters, the first transfer function, and the second transfer function, the noise reduction situation of each filter bank 104 for the current ear canal and / or wearing mode can be obtained, so that the matching ANC parameters can be selected more specifically and accurately, and the optimal noise reduction effect on the current ambient noise 105 can be achieved.

[0037] The processor 302 may be a processing device including more than one general-purpose processing device, such as a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), etc. More specifically, it may be a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a processor running other instruction sets, or a processor running a combination of instruction sets. It may also be more than one dedicated processing device, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), a system-on-chip (SoC), etc.

[0038] According to an embodiment of the present application, a noise-canceling headphone is also provided. The noise-canceling headphone 400 includes a feedforward microphone 101, a feedback microphone 102, a speaker 103, and the active noise-canceling system 300 described in any embodiment of the present application. The noise-canceling headphone 400 does not need to play a prompt tone or a special signal to select the ANC parameters for active noise cancellation, and has better applicability. The noise-canceling headphone 400 also does not need to traverse each filter bank, and the time to select the filter bank with the best noise-canceling effect is short, which improves the subjective experience of the user, and can accurately select the matching ANC parameters to achieve the optimal noise-canceling effect on the current ambient noise 105.

[0039] In addition, although exemplary embodiments have been described herein, the scope includes any and all embodiments based on the present application having equivalent elements, modifications, omissions, combinations (e.g., solutions that cross various embodiments), adaptations, or alterations. The elements in the claims will be broadly interpreted based on the language used in the claims and are not limited to the examples described in this specification or during the implementation of the present application, and the examples will be interpreted as non-exclusive. Therefore, this specification and the examples are intended to be considered only as examples, and the true scope and spirit are indicated by the following claims and the full scope of their equivalents.

[0040] The above description is intended to be illustrative rather than restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. For example, those of ordinary skill in the art can use other embodiments when reading the above description. In addition, in the above specific implementation manners, various features can be grouped together to simplify the present application. This should not be construed as an intention that a feature that is not claimed for protection is necessary for any claim. On the contrary, the subject matter of the present application may be less than all the features of a specific embodiment of the application. Thus, the following claims are incorporated herein as examples or embodiments into the specific implementation manners, where each claim independently serves as a separate embodiment, and it is contemplated that these embodiments can be combined with each other in various combinations or permutations. The scope of the present invention should be determined with reference to the appended claims and the full scope of the equivalents to which these claims are entitled.

[0041] The above embodiments are only exemplary embodiments of the present application and are not used to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements within the essence and protection scope of the present application, and such modifications or equivalent replacements should also be regarded as falling within the protection scope of the present invention.

Claims

1. An active noise reduction method for headphones, the headphones comprising a feedforward microphone, a feedback microphone and a speaker, characterized in that, The earphone further includes a plurality of filter banks, and the active noise cancellation method includes: when the active noise cancellation function of the earphone is turned on, acquiring a first noise signal currently collected by the feedforward microphone; acquiring a reverse signal played through the speaker, where the reverse signal is obtained by filtering the first noise signal by the current filter bank; calculating a first transfer function of the secondary channel based on the first noise signal, a second transfer function of the primary channel, the reverse signal, and a second noise signal detected by the feedback microphone Calculating noise residue curves corresponding to each filter bank based on the first transfer function of the secondary channel, the second transfer function of the primary channel, and the frequency response parameters of a plurality of filter banks with different ANC parameter configurations. Based on each noise residue curve, a matching filter bank is selected, and the current filter bank is configured with the ANC parameters corresponding to the matching filter bank.

2. The active noise reduction method according to claim 1, wherein Calculating the first transfer function of the secondary channel based on the first noise signal, the second transfer function of the primary channel, the reverse signal, and the second noise signal detected by the feedback microphone specifically includes: obtaining a conduction signal of the primary channel based on the first noise signal and the second transfer function; Calculating a first transfer function based on the relationship that the second noise signal is equal to the superposition of the conduction signal of the primary channel and the conduction signal of the secondary channel, where the conduction signal of the secondary channel is obtained based on the reverse signal and the first transfer function.

3. The active noise reduction method according to claim 1, wherein Calculating the noise residue curves of each filter bank based on the first transfer function of the secondary channel, the second transfer function of the primary channel, and the frequency response parameters of a plurality of filter banks with different ANC parameter configurations specifically includes: obtaining a target transfer function in the case of optimal noise reduction amount based on the first transfer function of the secondary channel and the second transfer function of the primary channel; Calculating the noise residue curves of each filter bank based on the target transfer function and the frequency response parameters of a plurality of filter banks with different ANC parameter configurations.

4. The active noise reduction method according to claim 3, wherein Obtaining the target transfer function in the case of optimal noise reduction amount based on the first transfer function of the secondary channel and the second transfer function of the primary channel specifically includes: calculating the target transfer function based on the relationship that the convolution of the target transfer function and the first transfer function is equal to the second transfer function.

5. The active noise reduction method according to claim 3, characterized in that Calculating the noise residue curves of each filter bank based on the target transfer function and the frequency response parameters of a plurality of filter banks with different ANC parameter configurations specifically includes: obtaining the noise residue curves of each filter bank based on the target transfer function, the frequency response parameters of each filter bank, and Equation (1), NR = 1 - Wff(z) / Wopt (1) where NR is the noise residue, Wff(z) is the frequency response parameter of the filter, and Wopt is the target transfer function.

6. The active noise reduction method according to any one of claims 1, characterized in that The active noise reduction method further includes: based on the noise residue curve, selecting the average value of the noise residue in a single frequency band or the average values of the noise residues in multiple different frequency bands as the noise residue of the filter bank to select a matching filter bank.

7. The active noise reduction method according to claim 1, wherein The active noise reduction method further includes: when the active noise reduction function of the earphone is turned off, obtaining a second transfer function of the primary channel based on the third noise signal collected by the feedforward microphone and the fourth noise signal collected by the feedback microphone.

8. The active noise reduction method according to claim 7, characterized in that Obtaining a second transfer function of the primary channel based on the third noise signal collected by the feedforward microphone and the fourth noise signal collected by the feedback microphone specifically includes: based on the third noise signal and the fourth noise signal, using an adaptive filtering algorithm, a time-domain algorithm, a frequency-domain algorithm or a Z-domain algorithm to obtain the second transfer function.

9. An active noise cancellation system for a headset, the headset including a feedforward microphone, a feedback microphone, and a speaker, characterized in that, The active noise reduction system further includes a processor and multiple filter banks, and the processor is configured to be respectively connected to the feedforward microphone, the feedback microphone, the speaker and each filter bank, and is used to execute the active noise reduction method according to any one of claims 1-8.

10. A noise-canceling headphone, characterized in that, The noise reduction earphone includes a feedforward microphone, a feedback microphone, a speaker and the active noise reduction system according to claim 9.

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