Noise reduction method, apparatus and system, electronic device, vehicle, and storage medium

Abstract

A noise reduction method, apparatus and system, an electronic device, a vehicle, and a storage medium. The method comprises: on the basis of a loudspeaker excitation signal and a microphone detection signal, determining a change parameter of a secondary channel; and on the basis of the change parameter, determining a noise reduction parameter and performing noise reduction control.

Description

Noise reduction method, device, system, electronic device, vehicle and storage medium

[0001] The present application claims priority to the Chinese patent application No. 202411237622.6, filed on September 4, 2024, the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates to the field of active noise reduction technology, and in particular to a noise reduction method, device, system, electronic device, vehicle and storage medium. BACKGROUND

[0003] With the rapid popularization of automobiles, users have increasingly high requirements for driving comfort. Active noise control (ANC) technology, as a noise reduction technology, is widely used in automobile noise reduction. SUMMARY

[0004] The present disclosure provides a noise reduction method, device, system, electronic device, vehicle and storage medium, aiming to solve the problem that the actual noise reduction effect is reduced or even abnormal sound occurs due to the change of the secondary channel.

[0005] In a first aspect, a noise reduction method is provided. The method comprises: determining a change parameter of a secondary channel based on a loudspeaker excitation signal and a microphone detection signal, and determining a noise reduction parameter according to the change parameter and performing noise reduction control.

[0006] The noise reduction method provided by some embodiments of the present disclosure can affect the active noise reduction effect due to the matching degree of the parameters of the secondary channel and the noise reduction parameter. Therefore, according to the loudspeaker excitation signal and the microphone detection signal in the actual vehicle cabin, some embodiments of the present disclosure determine the change parameter of the secondary channel in the current vehicle cabin, so as to determine the noise reduction parameter according to the change parameter, so that the updated noise reduction parameter matches the actual secondary channel, and thus the noise reduction control according to the updated noise reduction parameter can improve the noise reduction effect.

[0007] In a second aspect, a noise reduction device is provided. The device comprises a determination unit and a control unit. The determination unit is configured to determine a change parameter of a secondary channel based on a loudspeaker excitation signal and a microphone detection signal. The control unit is configured to determine a noise reduction parameter according to the change parameter and perform noise reduction control.

[0008] In a third aspect, a noise reduction system is provided. The noise reduction system comprises a reference signal acquisition module, a secondary channel filtering module, an active noise control module, a noise reduction signal generation module, an adaptive filter, a loudspeaker and a microphone. The noise reduction system executes the above noise reduction method to realize the noise control function.

[0009] In a fourth aspect, an electronic device is provided. The electronic device includes a processor and a memory storing processor-executable instructions. The processor is configured to execute the instructions to implement the noise reduction method described above.

[0010] In a fifth aspect, a vehicle is provided. The vehicle includes a memory, a processor, and a computer program stored on the memory and executable on the processor. The processor executes the computer program to implement the noise reduction method described above.

[0011] In some embodiments, the vehicle further includes an engine, a power amplifier, and the electronic device described above. The memory and the processor are integrated into at least one of the electronic device or the power amplifier to reduce the noise of the engine.

[0012] In a sixth aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores instructions. When a computer executes the instructions, the computer performs the noise reduction method described above.

[0013] In a seventh aspect, a computer program product including instructions is provided. When a computer executes the instructions, the computer performs the noise reduction method described above.

[0014] In an eighth aspect, a chip is provided. The chip includes a processor and a communication interface coupled to the processor. The processor is configured to execute a computer program or instructions to implement the noise reduction method described above. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings needed to be used in the embodiment description will be briefly introduced as follows. However, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can also be obtained by those of ordinary skill in the art without creative labor on the basis of these drawings.

[0016] FIG. 1 is a structural diagram of a noise reduction system based on secondary path delay estimation according to some embodiments;

[0017] FIG. 2 is a structural diagram of a noise reduction system based on online identification of a secondary path according to some embodiments;

[0018] FIG. 3 is a flowchart of a noise reduction method according to some embodiments;

[0019] FIG. 4 is another flowchart of a noise reduction method according to some embodiments;

[0020] FIG. 5A is a sampling diagram of a secondary path transfer function according to some embodiments;

[0021] FIG. 5B is another sampling diagram of a secondary channel transfer function according to some embodiments;

[0022] FIG. 5C is yet another sampling diagram of a secondary channel transfer function according to some embodiments;

[0023] FIG. 5D is yet another sampling diagram of a secondary channel transfer function according to some embodiments;

[0024] FIG. 6 is a flowchart of updating a secondary channel transfer function based on secondary channel delay estimation according to some embodiments;

[0025] FIG. 7 is yet another flowchart of a noise reduction method according to some embodiments;

[0026] FIG. 8 is a flowchart of updating a secondary channel transfer function based on online identification of secondary channel according to some embodiments;

[0027] FIG. 9 is a block diagram of a noise reduction apparatus according to some embodiments;

[0028] FIG. 10 is a block diagram of an electronic device according to some embodiments;

[0029] FIG. 11 is a block diagram of a vehicle according to some embodiments. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present disclosure will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present disclosure. However, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present disclosure.

[0031] In the description of the present disclosure, it should be understood that the terms "upper", "lower", "left", "right", "front", "back", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or relative position relationship shown in the drawings, and are only intended to facilitate the description of the present disclosure and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure. Unless otherwise specified, the above orientation description can be flexibly arranged in the process of actual application, as long as the relative position relationship shown in the drawings is met.

[0032] The terms "first", "second", etc. are used only to describe purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present disclosure, the meaning of "a plurality of" is two or more, unless otherwise specified.

[0033] In the description of the present disclosure, it should be explained that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection", "communication" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral connection. It can be directly connected, or indirectly connected through an intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present disclosure can be understood according to the specific circumstances.

[0034] In some embodiments, the terms "comprising", "containing" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, article or device. Without more limitations, the element defined by the sentence "including a" does not exclude the existence of other identical elements in the process, article or device including the element.

[0035] In some embodiments, the words "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "for example" should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of the words "exemplary" or "for example" is intended to present concepts in a concrete manner.

[0036] In the description of the present disclosure, features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0037] With the increasingly fierce market competition, users have higher and higher requirements for engine noise in the vehicle cabin. During the driving process of the vehicle, noise will inevitably be generated in the vehicle cabin due to the operation of the engine, affecting the driving experience of the user. At present, a large number of vehicles on the market are equipped with active noise control (ANC) technology, which is used to reduce the noise in the vehicle cabin and improve the noise, vibration and harshness (NVH) performance of the vehicle. For example, when the vehicle is delivered, based on various parameters in the vehicle cabin, a secondary channel is identified, and a transfer function for noise reduction is measured, and the transfer function is set in the vehicle hardware, so as to realize the elimination of noise in the vehicle cabin.

[0038] At present, an adaptive filter algorithm (Filtered-x Least Mean Squares, FxLMS) is usually used in the ANC system. The excitation signal generated in the FxLMS algorithm is transmitted through a power amplifier, a loudspeaker, a vehicle cabin environment, and a microphone to measure a signal, and this path is called a secondary channel. In the FxLMS algorithm, the secondary channel transfer function is used to represent the path, and the secondary channel transfer function is one of the important parameters in the ANC system, which is directly related to the noise reduction effect and stability of the ANC system.

[0039] In related technologies, the most widely used technology in the ANC system is an automobile cabin active noise control system based on offline identification of the secondary channel. For example, in the parameter calibration process of algorithm development, the secondary channel is identified, the secondary channel transfer function is measured, and then the secondary channel transfer function is downloaded to the automobile hardware as a fixed parameter.

[0040] However, during the use of the automobile, a large number of factors may change the secondary channel. For example, the user replaces the loudspeaker, the device aging caused by the use of the vehicle, the change of the load in the vehicle, and the change of the software version of the vehicle, etc. The change of the secondary channel may cause the actual secondary channel transfer function to be different from the transfer function used in the FxLMS algorithm, which may cause the noise reduction effect of the ANC system on the noise in the vehicle cabin to decrease, and even may cause the ANC algorithm to diverge and generate abnormal noise.

[0041] In this background, in order to solve the problem of the decrease of the noise reduction effect on the noise in the vehicle cabin in related technologies, some embodiments of the present disclosure provide a noise reduction method, device, system, electronic equipment, vehicle and storage medium. Some embodiments of the present disclosure are described below in conjunction with the drawings of the specification.

[0042] As shown in FIG. 1, a structural diagram of a noise reduction system based on secondary path delay estimation is provided for some embodiments of the present disclosure. The noise reduction system 100 includes a reference signal acquisition module 110, a secondary path filter module 120, an active noise control module 130, a noise reduction signal generation module 140, a cabin sound source module 150, a scene detection module 160, a delay estimation module 170, and a secondary path delay matching module 180.

[0043] The reference signal acquisition module 110 is connected with the secondary path filter module 120 and the noise reduction signal generation module 140 respectively, and the secondary path filter module 120 is connected with the active noise control module 130. The active noise control module 130 is connected with the noise reduction signal generation module 140, and the noise reduction signal generation module 140 is connected with the scene detection module 160 and the loudspeaker respectively. The cabin sound source module 150 is connected with the scene detection module 160, the adaptive filter, and the loudspeaker respectively, and the scene detection module 160 is connected with the delay estimation module 170. The delay estimation module 170 is connected with the secondary path delay matching module 180, and the adaptive filter is connected with the active noise control module 130 and the secondary path delay matching module 180 respectively. The microphone is connected with the active noise control module 130 and the delay estimation module 170 respectively, and the secondary path delay matching module 180 is connected with the secondary path filter module 120.

[0044] In some embodiments, the reference signal acquisition module 110 is configured to acquire a noise reference signal x(t) (such as a sound signal, a vibration signal) through an in-vehicle sensor, the noise reduction signal generation module 140 is configured to perform noise reduction processing on the noise reference signal x(t) to generate an active noise reduction signal y(t), the cabin sound source module 150 is configured to generate a cabin sound source signal m(t) (such as a music signal, a navigation signal), and the microphone is configured to measure the cabin sound signal to obtain a microphone detection signal e(t).

[0045] In some embodiments, the active noise reduction signal y(t) and the cabin sound source signal m(t) are input into the loudspeaker, and the loudspeaker is configured to output a loudspeaker excitation signal s(t) synthesized by the cabin sound source signal m(t) and the active noise reduction signal y(t), which cancels the original cabin noise signal to achieve the active noise reduction function. The adaptive filter is configured to filter the cabin sound source signal m(t) to obtain a filtered cabin sound source signal The secondary path filter module 120 is configured to filter the noise reference signal x(t) to obtain a filtered noise reference signal The active noise control module 130 is configured to obtain a filtered noise reference signal The microphone detection signal e(t) and the filtered noise reference signal updating the noise reduction parameter in the noise reduction signal generation module 140.

[0046] In some embodiments, the active noise reduction signal y(t) and the cabin sound source signal m(t) are input into a scene detection module 160, which is configured to detect a loudspeaker excitation signal s(t) synthesized from the cabin sound source signal m(t) and the active noise reduction signal y(t). A delay estimation module 170 is configured to perform secondary path delay estimation according to the loudspeaker excitation signal s(t) and the microphone detection signal e(t) if the loudspeaker excitation signal s(t) meets delay estimation requirements, to obtain a secondary path delay. A secondary path delay matching module 180 is configured to update the secondary path transfer function in the secondary path filtering module 120 according to the secondary path delay.

[0047] Thus, some embodiments of the present disclosure update the current secondary path transfer function based on delay estimation by obtaining the loudspeaker excitation signal and the microphone detection signal, to obtain a secondary path transfer function matching the actual secondary path, so as to improve the active noise reduction effect when active noise reduction control is performed based on the new secondary path transfer function.

[0048] As shown in FIG. 2, a structure diagram of a noise reduction system based on online identification of a secondary path according to some embodiments of the present disclosure is provided. The noise reduction system 200 includes a reference signal acquisition module 210, a secondary path filtering module 220, an active noise control module 230, a noise reduction signal generation module 240, a cabin sound source module 250, a signal detection module 260, and an online secondary path estimation module 270.

[0049] The reference signal acquisition module 210 is connected to the secondary path filtering module 220 and the noise reduction signal generation module 240, respectively. The secondary path filtering module 220 is connected to the active noise control module 230. The active noise control module 230 is connected to the noise reduction signal generation module 240. The noise reduction signal generation module 240 is connected to the signal detection module 260 and the loudspeaker, respectively. The cabin sound source module 250 is connected to the signal detection module 260, the adaptive filter, and the loudspeaker, respectively. The signal detection module 260 is connected to the online secondary path estimation module 270. The adaptive filter is connected to the active noise control module 230 and the online secondary path estimation module 270, respectively. The microphone is connected to the active noise control module 230 and the online secondary path estimation module 270, respectively. The online secondary path estimation module 270 is connected to the secondary path filtering module 220.

[0050] In some embodiments, the reference signal acquisition module 210 is configured to acquire a noise reference signal x(t) (such as a sound signal, a vibration signal) through an in-vehicle sensor, and the noise reduction signal generation module 240 is configured to perform noise reduction processing on the noise reference signal x(t) to generate an active noise reduction signal y(t). The cabin sound source module 250 is configured to generate a cabin sound source signal m(t) (such as a music signal, a navigation signal), and the microphone is configured to measure the cabin sound signal to obtain a microphone detection signal e(t).

[0051] In some embodiments, the active noise reduction signal y(t) and the cabin sound source signal m(t) are input into a loudspeaker, and the loudspeaker is configured to output a loudspeaker excitation signal s(t) synthesized by the cabin sound source signal m(t) and the active noise reduction signal y(t), and the loudspeaker excitation signal s(t) cancels the original cabin noise signal to achieve an active noise reduction function. The adaptive filter is configured to filter the cabin sound source signal m(t) to obtain a filtered cabin sound source signal The secondary path filter module 220 is configured to filter the noise reference signal x(t) to obtain a filtered noise reference signal The active noise control module 230 is configured to update the secondary path transfer function in the secondary path filter module 220 according to the filtered cabin sound source signal The microphone detection signal e(t) and the filtered noise reference signal The noise reduction parameter in the noise reduction signal generation module 240 is updated.

[0052] In other embodiments, the active noise reduction signal y(t) and the cabin sound source signal m(t) are input into a signal detection module 260, and the signal detection module 260 is configured to detect the loudspeaker excitation signal s(t) synthesized by the cabin sound source signal m(t) and the active noise reduction signal y(t). The online secondary path estimation module 270 is configured to perform adaptive filtering processing on the loudspeaker excitation signal s(t) and the microphone detection signal e(t) to obtain a filtering parameter when the loudspeaker excitation signal s(t) meets the online identification requirement, and update the secondary path transfer function in the secondary path filter module 220 according to the filtering parameter.

[0053] It should be noted that the synthesis function described in the above FIG. 1 and FIG. 2 can be realized by a power amplifier (such as a power amplifier) and an electronic device (such as a vehicle-mounted host) in the vehicle.

[0054] In this way, some embodiments of the present disclosure update the current secondary path transfer function by acquiring the loudspeaker excitation signal and the microphone detection signal and combining the adaptive filtering algorithm, to obtain a secondary path transfer function that matches the actual secondary path, so that the active noise reduction effect can be improved when the active noise reduction control is performed based on the new secondary path transfer function.

[0055] The noise reduction method provided by some embodiments of the present disclosure is described below with reference to Figs. 1 and 2, and Figs. 3-8.

[0056] Fig. 3 is a flowchart of the noise reduction method provided by some embodiments of the present disclosure. The subject performing the method can be a noise reduction system, or each device or module in the noise reduction system, such as an integrated circuit or chip, which is not limited in the present disclosure.

[0057] In some embodiments, as shown in Fig. 3, the noise reduction method provided by some embodiments of the present disclosure can include the following S301 and S302:

[0058] In S301, based on the loudspeaker excitation signal and the microphone detection signal, a change parameter of the secondary channel is determined.

[0059] In some examples, the noise reference signal can be acquired in real time by a sensor, and the cabin sound source signal can be acquired in real time, and then based on the noise reference signal and the cabin sound source signal, the loudspeaker excitation signal is generated.

[0060] For example, as shown in Fig. 1, in the case that the vehicle engine is running, the loudspeaker excitation signal can be obtained by synthesizing the reference signal collected by the reference signal collection module 110 after noise reduction by the noise reduction signal generation module 140, and the cabin sound source signal output by the cabin sound source module 150.

[0061] For another example, as shown in Fig. 1, in the case that the engine stops running, the loudspeaker excitation signal can be obtained by processing the cabin sound source signal output by the cabin sound source module 150.

[0062] In some examples, the above-mentioned generation of the loudspeaker excitation signal based on the noise reference signal and the cabin sound source signal can include: performing noise reduction processing on the noise reference signal to obtain a noise reduction signal, and then synthesizing the noise reduction signal and the cabin sound source signal into the loudspeaker excitation signal.

[0063] In some embodiments, the loudspeaker excitation signal can include at least one of the following: the noise reduction signal, the cabin sound source signal. The noise reduction signal can include a sound signal, a vibration signal, etc. after noise reduction processing; the cabin sound source signal can include a music sound signal, a navigation sound signal, etc.

[0064] In some examples, the sound signal in the cabin can be collected in real time by a microphone to obtain a microphone detection signal.

[0065] In some embodiments, the microphone detection signal can be all sound signals in the vehicle cabin. For example, the microphone detection signal can include at least one of the following: a human voice signal, a background noise signal, a signal output by the loudspeaker excitation signal through the loudspeaker, etc.

[0066] In some embodiments, when the vehicle engine is stopped, the speaker excitation signal and microphone detection signal do not include engine noise signal.

[0067] In some embodiments of this disclosure, a secondary channel refers to the signal transmission path from the moment the speaker excitation signal is processed by the speaker until the microphone detection signal is received by the microphone.

[0068] In some embodiments, delay estimation and delay matching of the secondary channel can be performed based on the speaker excitation signal and the microphone detection signal to obtain the variation parameters. In this case, the variation parameters include the signal delay duration.

[0069] In other embodiments, secondary channel online identification can be performed based on the speaker excitation signal and the microphone detection signal to obtain the changing parameters of the secondary channel. In this case, the changing parameters include filtering parameters.

[0070] In S302, noise reduction parameters are determined based on the changing parameters and noise reduction control is performed.

[0071] In some embodiments, the secondary channel transfer function between the speaker and the microphone can be updated based on the changing parameters. Then, the noise reduction parameters are updated based on the updated secondary channel transfer function, and noise reduction control is performed based on the updated noise reduction parameters.

[0072] The secondary channel transfer function is used to characterize the signal transmission path from the moment the loudspeaker excitation signal is processed by the loudspeaker until the microphone detection signal is received by the microphone.

[0073] In some embodiments, the transfer function at the current moment can be updated based on the speaker excitation signal and microphone detection signal acquired at the current moment to obtain the secondary channel transfer function at the current moment for use in the next moment.

[0074] For example, let's take the current time as n and the next time as n+1. If the obtained loudspeaker excitation signal is X... n And the microphone detection signal is Y n At this point, the secondary channel transfer function Z at time n can be considered. n The secondary channel transfer function Z is updated to obtain the updated transfer function Z. n+1 The updated secondary channel transfer function Z is used at time n+1. n+1 Perform active noise cancellation.

[0075] As described in S301, in some embodiments, the signal delay duration can be determined based on the speaker excitation signal and the microphone detection signal, and then the secondary channel transfer function between the speaker and the microphone can be updated based on the signal delay duration.

[0076] As described in S301, in another embodiment, the secondary channel online identification can be performed based on the loudspeaker excitation signal and the microphone detection signal to obtain a filter parameter of an adaptive filter algorithm, and then the filter parameter is used to update the secondary channel transfer function between the loudspeaker and the microphone.

[0077] In some embodiments, after obtaining the updated secondary channel transfer function, the engine noise signal can be filtered according to the updated secondary channel transfer function to obtain a filtered noise signal. Then, the noise reduction parameter is determined according to the filtered noise signal and the microphone detection signal. The engine noise signal is processed according to the noise reduction parameter to generate a noise reduction signal, and the noise reduction signal is output through the loudspeaker.

[0078] The noise reduction signal is used to suppress the original cabin noise signal. The frequency of the noise reduction signal is the same as that of the original cabin noise, and the phase of the noise reduction signal is opposite to that of the original cabin noise.

[0079] For example, taking the frequency of the engine noise signal as 100 Hz and the phase as 50 degrees. After obtaining the new noise reduction parameter, the engine noise signal can be processed to obtain a noise reduction signal, and the frequency of the noise reduction signal is 100 Hz and the phase is 230 degrees. At this time, since the frequency of the engine noise signal is the same as that of the noise reduction signal, and the phase of the engine noise signal is 180 degrees different from that of the noise reduction signal (i.e. opposite phase), the noise reduction signal can cancel the engine noise signal in the vehicle cabin.

[0080] In the noise reduction method provided by some embodiments of the present disclosure, the matching degree of the secondary channel parameter and the noise reduction parameter can affect the active noise reduction effect. Therefore, some embodiments of the present disclosure determine the change parameter of the secondary channel in the actual vehicle cabin according to the loudspeaker excitation signal and the microphone detection signal in the actual vehicle cabin, so as to determine the noise reduction parameter according to the change parameter, so that the updated noise reduction parameter matches the actual secondary channel, and thus the noise reduction control according to the updated noise reduction parameter can improve the noise reduction effect.

[0081] As described in S302 above, in some embodiments, the signal delay duration can be determined based on the loudspeaker excitation signal and the microphone detection signal, and then the secondary channel transfer function between the loudspeaker and the microphone is updated based on the signal delay duration. The solution of updating the secondary channel transfer function between the loudspeaker and the microphone based on the signal delay duration will be given below in combination with the embodiment shown in FIG. 4.

[0082] For example, as shown in FIG. 4, the noise reduction method provided by some embodiments of the present disclosure can include the following S401 to S403:

[0083] In S401, a period delay parameter and a phase delay parameter are determined based on the loudspeaker excitation signal and the microphone detection signal.

[0084] The period delay parameter is used to represent a period number of a phase difference between the microphone detection signal and the loudspeaker excitation signal, and the phase delay parameter is used to represent a phase value of the phase difference between the microphone detection signal and the loudspeaker excitation signal.

[0085] In some embodiments, the period delay parameter can be determined according to a coherence of the loudspeaker excitation signal and the microphone detection signal on at least one of a time domain or a frequency domain. It should be noted that “at least one of A, B and C” has the same meaning as “at least one of A, B or C”, which includes the following combinations of A, B and C: only A, only B, only C, a combination of A and B, a combination of A and C, a combination of B and C, and a combination of A, B and C.

[0086] The coherence is used to represent a degree of similarity of the loudspeaker excitation signal and the microphone detection signal on the time domain or the frequency domain.

[0087] In some embodiments, a cross-correlation function of the loudspeaker excitation signal and the microphone detection signal can be calculated, and the period number of the phase difference can be determined by determining a maximum point of the cross-correlation function.

[0088] In some embodiments, the phase delay parameter can be determined according to a phase difference value of the loudspeaker excitation signal and the microphone detection signal on the frequency domain.

[0089] For example, the phase difference value of the loudspeaker excitation signal and the microphone detection signal on the frequency domain can be accurately calculated by using a sound source positioning method to determine the phase delay parameter.

[0090] In some embodiments, before the period delay parameter is determined according to the coherence of the loudspeaker excitation signal and the microphone detection signal on at least one of the time domain or the frequency domain, it can be judged whether the loudspeaker excitation signal satisfies at least one of the following conditions: the loudspeaker excitation signal does not contain a noise reduction signal, a signal-to-noise ratio of the loudspeaker excitation signal and a noise signal is greater than or equal to a first signal-to-noise ratio, and a frequency of the loudspeaker excitation signal is less than or equal to a preset frequency.

[0091] In some embodiments, the first signal-to-noise ratio can be a value set artificially, and the first signal-to-noise ratio can be flexibly adjusted according to an actual scene. For example, the first signal-to-noise ratio can be 30 decibels.

[0092] It should be noted that since the signal-to-noise ratio can represent the clarity of the loudspeaker excitation signal relative to the background noise. Therefore, the higher the signal-to-noise ratio, the clearer the loudspeaker excitation signal.

[0093] In some embodiments, the preset frequency can be a value set by a person, and the preset frequency can be flexibly adjusted according to an actual scene. For example, the preset frequency can be 8000 Hz.

[0094] It should be noted that, in order to make the energy of the loudspeaker excitation signal more concentrated, a preset frequency (such as 8000 Hz) can be set, so that the frequency of the loudspeaker excitation signal is below 8000 Hz, thereby making the secondary path transfer function updated by the loudspeaker excitation signal more accurate.

[0095] In this way, some embodiments of the present disclosure can further judge the update condition before updating the secondary path transfer function, thereby further improving the accuracy of the updated secondary path transfer function.

[0096] In some embodiments, the periodic delay parameter and the phase delay parameter can be determined in real time based on the loudspeaker excitation signal and the microphone detection signal.

[0097] In some examples, the periodic delay parameter and the phase delay parameter are determined after the loudspeaker excitation signal and the microphone detection signal are obtained each time.

[0098] In some embodiments, the periodic delay parameter and the phase delay parameter can be determined based on the loudspeaker excitation signal and the microphone detection signal at a preset time interval.

[0099] In some examples, the loudspeaker excitation signal and the microphone detection signal can be obtained first, and then the periodic delay parameter and the phase delay parameter are determined when the actual interval duration reaches the preset time interval.

[0100] The preset time interval can be a value set by a person, and the preset time interval can be flexibly adjusted according to an actual scene. For example, the preset time interval can be 5 days.

[0101] For example, taking 5 days as the preset time interval, if the actual interval duration reaches 5 days, the periodic delay parameter and the phase delay parameter are determined.

[0102] In S402, the signal delay duration between the microphone detection signal and the loudspeaker excitation signal is determined based on the periodic delay parameter and the phase delay parameter.

[0103] In some embodiments, since the periodic delay parameter is used to represent the number of periods of the phase difference, the whole period duration of the phase difference between the loudspeaker excitation signal and the microphone detection signal can be calculated according to the period duration of the signal and the number of periods of the phase difference.

[0104] For example, taking the period length of the signal as 2 milliseconds, if the calculated number of periods is 4, the whole period length of the difference between the loudspeaker excitation signal and the microphone detection signal can be obtained as 8 milliseconds.

[0105] In some embodiments, since the phase delay parameter is used to represent the phase value of the difference, the delay length of the difference between the loudspeaker excitation signal and the microphone detection signal within a period can be calculated according to the frequency of the signal.

[0106] For example, taking the frequency of the signal as 100 Hz, if the calculated phase value of the difference is 45 degrees, the delay length between the loudspeaker excitation signal and the microphone detection signal can be calculated as 1.25 milliseconds according to formula (I). Formula (I) is as follows:

[0107] is the phase value of the difference, and Δt is the delay length.

[0108] In some embodiments, the whole period length of the difference between the loudspeaker excitation signal and the microphone detection signal and the delay length within a period can be added to obtain the signal delay length.

[0109] For example, taking the whole period length of the difference between the loudspeaker excitation signal and the microphone detection signal as 8 milliseconds and the delay length within a period as 1.25 milliseconds, the signal delay length can be calculated as 8+1.25=9.25 milliseconds.

[0110] In S403, the secondary path transfer function between the loudspeaker and the microphone is updated based on the signal delay length.

[0111] For example, the signal delay length between the microphone detection signal and the loudspeaker excitation signal can be used to adjust the signal delay length of the secondary path transfer function between the loudspeaker and the microphone, so as to update the secondary path transfer function between the loudspeaker and the microphone.

[0112] In some embodiments, the secondary path transfer function between the loudspeaker and the microphone can be first up-sampled to identify the signal delay length of the secondary path transfer function between the loudspeaker and the microphone, and then the signal delay length between the microphone detection signal and the loudspeaker excitation signal can be used to adjust the signal delay length of the secondary path transfer function between the loudspeaker and the microphone. Then the adjusted secondary path transfer function between the loudspeaker and the microphone is down-sampled to update the secondary path transfer function between the loudspeaker and the microphone.

[0113] In some embodiments, the number of sampling points corresponding to the signal delay length of the secondary path transfer function between the loudspeaker and the microphone can be adjusted to adjust the signal delay length.

[0114] For example, as shown in FIG. 5A, the secondary channel transfer function can be up-sampled to obtain a signal delay duration in the secondary channel transfer function as shown in FIG. 5B. At this time, if the new signal delay duration is calculated to be less than the original signal delay duration, as shown in FIG. 5C, the sampling points with the head amplitude close to 0 are reduced to adjust the original signal delay duration to be the same as the new signal delay duration, and the sampling points with the tail amplitude close to 0 are increased to ensure the frequency consistency of the transfer function. Then, as shown in FIG. 5D, the adjusted secondary channel transfer function is down-sampled to obtain the updated secondary channel transfer function.

[0115] It should be noted that, since no signal is received within the signal delay duration, the part with the head amplitude close to 0 in FIGS. 5A-5D is the signal delay duration in the secondary channel transfer function.

[0116] In this way, the embodiments of the present disclosure estimate the transmission delay duration of the signal in the current secondary channel by respectively calculating the whole-cycle delay duration and the phase delay duration within the cycle of the signal transmission in the current secondary channel, thereby improving the accuracy of the obtained signal delay duration, and updating the current secondary channel transfer function through the signal delay duration, so that the updated secondary channel transfer function matches the current secondary channel, thereby improving the active noise reduction effect.

[0117] The overall implementation process of updating the secondary channel transfer function based on delay estimation provided in some embodiments of the present disclosure is exemplarily described below.

[0118] For example, as shown in FIG. 6, the complete process of updating the secondary channel transfer function based on the secondary channel delay estimation provided by some embodiments of the present disclosure can include the following S601-S609.

[0119] In S601, the loudspeaker excitation signal and the microphone detection signal are obtained. At least one of S602-S604 is performed.

[0120] In S602, it is judged whether there is a noise reduction signal in the loudspeaker excitation signal. If yes, S609 is performed; if no, S605 is performed.

[0121] In S603, it is judged whether the signal-to-noise ratio of the loudspeaker excitation signal and the noise signal is greater than or equal to a first signal-to-noise ratio. If yes, S605 is performed; if no, S609 is performed.

[0122] In S604, it is judged whether the frequency of the loudspeaker excitation signal is less than or equal to a preset frequency. If yes, S605 is performed; if no, S609 is performed.

[0123] In S605, coherence of the loudspeaker excitation signal and the microphone detection signal is calculated to obtain a periodic delay parameter.

[0124] In S606, a phase difference of the loudspeaker excitation signal and the microphone detection signal is calculated to obtain a phase delay parameter.

[0125] In S607, a signal delay duration between the loudspeaker excitation signal and the microphone detection signal is obtained according to the periodic delay parameter and the phase delay parameter.

[0126] In S608, a signal delay duration of the original secondary path transfer function is adjusted according to the signal delay duration to obtain an updated secondary path transfer function.

[0127] In S609, the noise reduction control scenario is entered.

[0128] As described in S301 above, in some embodiments, the secondary path can be identified online based on the loudspeaker excitation signal and the microphone detection signal to obtain a filter parameter of an adaptive filter algorithm, and then the secondary path transfer function between the loudspeaker and the microphone is updated based on the filter parameter. The solution of online identification and update of the secondary path transfer function based on the adaptive filter algorithm will be given below in combination with the embodiment shown in FIG. 7.

[0129] In some embodiments, the adaptive filter algorithm can be used to perform adaptive filter processing on the loudspeaker excitation signal and the microphone detection signal to obtain the filter parameter.

[0130] The adaptive filter algorithm can be a least mean square (LMS) algorithm or a recursive least squares (RLS) algorithm.

[0131] In some embodiments, before the adaptive filter processing based on the adaptive filter algorithm is performed on the loudspeaker excitation signal and the microphone detection signal to obtain the filter parameter, it can be determined whether the loudspeaker excitation signal satisfies at least one of the following conditions: the noise reduction signal is not present in the loudspeaker excitation signal, and a signal-to-noise ratio of the loudspeaker excitation signal and the microphone detection signal and the noise signal is greater than or equal to a second signal-to-noise ratio.

[0132] In some embodiments, in the case that the noise reduction signal is included in the loudspeaker excitation signal, the loudspeaker excitation signal is output through the loudspeaker to eliminate the noise signal in the vehicle cabin.

[0133] In some embodiments, the second signal-to-noise ratio can be a value artificially set, and the second signal-to-noise ratio can be flexibly adjusted according to an actual scene. For example, the second signal-to-noise ratio can be 40 decibels. It should be noted that the signal-to-noise ratio can represent the clarity of the loudspeaker excitation signal and the microphone detection signal relative to background noise. Therefore, the higher the signal-to-noise ratio, the clearer the loudspeaker excitation signal and the microphone detection signal.

[0134] In this way, some embodiments of the present disclosure can further judge the update condition before performing the secondary path transfer function update, thereby further improving the accuracy of the updated secondary path transfer function.

[0135] In some embodiments, the adaptive filtering algorithm can be used to perform adaptive filtering on the loudspeaker excitation signal and the microphone detection signal in real time online to determine the filtering parameter.

[0136] In some embodiments, the adaptive filtering algorithm can be used to perform adaptive filtering on the loudspeaker excitation signal and the microphone detection signal in real time online to determine the filtering parameter.

[0137] In this way, by updating the secondary path transfer function in real time online, the timeliness of the secondary path transfer function can be ensured.

[0138] For example, as shown in FIG. 7, the noise reduction method provided by some embodiments of the present disclosure can include the following S701 to S704:

[0139] In S701, the adaptive filtering algorithm is used to filter the loudspeaker excitation signal to obtain the simulated microphone detection signal.

[0140] In some embodiments, as shown in FIG. 2, the adaptive filtering algorithm can be used to simulate the secondary path transfer function between the loudspeaker and the microphone by using the adaptive filter to filter the loudspeaker excitation signal to obtain the simulated microphone detection signal.

[0141] For example, taking the loudspeaker excitation signal as X n , the microphone detection signal as Y n , and the initial filtering parameter of the adaptive filter as , for example, the loudspeaker excitation signal X n is input into the adaptive filter with the initial filtering parameter to obtain the simulated microphone detection signal X 1 n .

[0142] In S702, the error signal between the simulated microphone detection signal and the microphone detection signal is determined.

[0143] For example, an analog microphone detection signal X 1 n The difference between the microphone detection signal Y n and the error signal E n .

[0144] In S703, filter parameters are determined based on the loudspeaker excitation signal and the error signal.

[0145] In some embodiments, the filter parameters can be obtained by random gradient processing based on the loudspeaker excitation signal and the error signal.

[0146] For example, the filter parameters can be obtained by random gradient processing based on the loudspeaker excitation signal X n and the error signal E n .

[0147] In some embodiments, the filter parameters can be obtained by iterative processing. For example, the filter parameters , the filter parameters , the filter parameters , the filter parameters , and the filter parameters may be obtained.

[0148] In S704, when the variation range of the filter parameters in the continuous preset number of times is less than or equal to the preset variation range, the secondary path transfer function between the loudspeaker and the microphone is updated according to the filter parameters.

[0149] In some embodiments, the preset number of times can be a value set by a person, and the preset number of times can be flexibly adjusted according to the actual scene. For example, the preset number of times can be 20 times. Similarly, the preset variation range can also be a value set by a person. For example, the preset variation range can be 5%.

[0150] For example, taking the preset number of times as 5 times and the preset variation range as 5% as an example. If the filter parameters obtained by the adaptive filter in the continuous 5 times are: the filter parameters with a variation range of 4.5%, the filter parameters with a variation range of 4%, the filter parameters with a variation range of 3.5%, the filter parameters with a variation range of 3%, and the filter parameters with a variation range of 3%, at this time, since the variation ranges of the filter parameters in the continuous 5 times are all less than 5%, the updated secondary path transfer function can be obtained according to the filter parameters .

[0151] Thus, some embodiments of the present disclosure determine whether the secondary path transfer function simulated by the adaptive filter matches the actual secondary path by determining whether the filter parameters used by the adaptive filter for filtering multiple times tend to be stable, so as to ensure that the updated secondary path transfer function matches the actual secondary path.

[0152] The overall implementation process of updating the secondary path transfer function based on online identification provided in some embodiments of the present disclosure is exemplarily described below.

[0153] For example, as shown in FIG. 8, the complete process of updating the secondary path transfer function based on online identification of the secondary path provided by some embodiments of the present disclosure can include the following S801 to S809.

[0154] In S801, the loudspeaker excitation signal and the microphone detection signal are obtained. At least one of S802 or S803 is performed.

[0155] In S802, it is determined whether the loudspeaker excitation signal contains a noise reduction signal. If yes, S809 is performed; if no, S804 is performed.

[0156] In S803, it is determined whether the signal-to-noise ratio of the loudspeaker excitation signal and the microphone detection signal to the noise signal is greater than or equal to a second signal-to-noise ratio. If yes, S804 is performed; if no, S809 is performed.

[0157] In S804, the loudspeaker excitation signal is filtered using an adaptive filtering algorithm to obtain a simulated microphone detection signal.

[0158] In S805, an error signal between the simulated microphone detection signal and the microphone detection signal is determined.

[0159] In S806, a filter parameter is determined based on the loudspeaker excitation signal and the error signal.

[0160] In S807, it is determined whether the variation range of the filter parameter at each time within a preset number of times is less than or equal to a preset variation range. If yes, S808 is performed; if no, S804 is performed.

[0161] In S808, an updated secondary path transfer function is obtained according to the filter parameter.

[0162] In S809, the noise reduction control scene is entered.

[0163] In some embodiments, in the case that the loudspeaker excitation signal satisfies at least one of the following conditions, the noise reduction control can be performed based on the loudspeaker excitation signal: the loudspeaker excitation signal contains a noise reduction signal, the signal-to-noise ratio of the loudspeaker excitation signal to the noise signal is less than a first signal-to-noise ratio, and the frequency of the loudspeaker excitation signal is greater than a preset frequency.

[0164] In some embodiments, in the case that the loudspeaker excitation signal comprises a noise reduction signal, the loudspeaker excitation signal is output through the loudspeaker in FIG. 1 to perform noise reduction control to eliminate a noise signal in the vehicle cabin.

[0165] The above mainly describes the solutions provided by some embodiments of the present disclosure from the perspective of methods. To implement the above functions, the noise reduction device or the electronic device comprises at least one of the hardware structure or the software module for performing each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of the examples described in the embodiments disclosed herein, the present disclosure can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is implemented in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present disclosure.

[0166] Some embodiments of the present disclosure can divide the noise reduction device or the electronic device into functional modules according to the above method. For example, the noise reduction device or the electronic device can comprise functional modules corresponding to each functional division, or two or more functions can be integrated into one processing module. The integrated module can be implemented in the form of hardware or software functional module. It should be noted that the division of modules in some embodiments of the present disclosure is illustrative, and is only a logical functional division. Actual implementation can have another division manner.

[0167] FIG. 9 is a block diagram of a noise reduction device according to some embodiments of the present disclosure. As shown in FIG. 9, the noise reduction device 900 comprises a determination unit 901 and a control unit 902.

[0168] The determination unit 901 is configured to determine a change parameter of a secondary path based on a loudspeaker excitation signal and a microphone detection signal. The control unit 902 is configured to determine a noise reduction parameter according to the change parameter and perform noise reduction control.

[0169] In some embodiments, the control unit 902 is configured to update a secondary path transfer function between the loudspeaker and the microphone according to the change parameter, update the noise reduction parameter based on the updated secondary path transfer function, and perform noise reduction control based on the updated noise reduction parameter.

[0170] In some embodiments, the determination unit 901 is configured to determine the period delay parameter and the phase delay parameter based on the loudspeaker excitation signal and the microphone detection signal, where the period delay parameter is used to represent a number of periods of the phase difference between the microphone detection signal and the loudspeaker excitation signal, and the phase delay parameter is used to represent a phase value of the phase difference between the microphone detection signal and the loudspeaker excitation signal.

[0171] In some embodiments, the determination unit 901 is configured to determine the period delay parameter based on the coherence of the loudspeaker excitation signal and the microphone detection signal in at least one of the time domain or the frequency domain, and determine the phase delay parameter based on the phase difference between the loudspeaker excitation signal and the microphone detection signal in the frequency domain.

[0172] In some embodiments, the determination unit 901 is configured to determine the period delay parameter based on the coherence of the loudspeaker excitation signal and the microphone detection signal in at least one of the time domain or the frequency domain, in a case where at least one of the following conditions is met. The conditions include that the noise reduction signal is not present in the loudspeaker excitation signal, a signal-to-noise ratio of the loudspeaker excitation signal and the noise signal is greater than or equal to a first signal-to-noise ratio, and a frequency of the loudspeaker excitation signal is less than or equal to a preset frequency.

[0173] In some embodiments, the control unit 902 is configured to determine a signal delay duration between the microphone detection signal and the loudspeaker excitation signal based on the period delay parameter and the phase delay parameter, and update the secondary path transfer function between the loudspeaker and the microphone based on the signal delay duration.

[0174] In some embodiments, the control unit 902 is configured to adjust the signal delay duration of the secondary path transfer function between the loudspeaker and the microphone by using the signal delay duration between the microphone detection signal and the loudspeaker excitation signal, to update the secondary path transfer function between the loudspeaker and the microphone.

[0175] In some embodiments, the control unit 902 is configured to perform up-sampling on the secondary path transfer function between the loudspeaker and the microphone, identify the signal delay duration of the secondary path transfer function between the loudspeaker and the microphone, adjust the signal delay duration of the secondary path transfer function between the loudspeaker and the microphone by using the signal delay duration between the microphone detection signal and the loudspeaker excitation signal, perform down-sampling on the adjusted secondary path transfer function between the loudspeaker and the microphone, and update the secondary path transfer function between the loudspeaker and the microphone.

[0176] In some embodiments, the determination unit 901 is configured to: determine the periodic delay parameter and the phase delay parameter in real time based on the loudspeaker excitation signal and the microphone detection signal; or determine the periodic delay parameter and the phase delay parameter at preset time intervals based on the loudspeaker excitation signal and the microphone detection signal.

[0177] In some embodiments, the determination unit 901 is configured to: perform adaptive filtering processing on the loudspeaker excitation signal and the microphone detection signal based on an adaptive filtering algorithm to obtain the filtering parameter.

[0178] In some embodiments, the determination unit 901 is configured to: filter the loudspeaker excitation signal using an adaptive filtering algorithm to obtain a simulated microphone detection signal, determine an error signal between the simulated microphone detection signal and the microphone detection signal, and determine the filtering parameter based on the loudspeaker excitation signal and the error signal.

[0179] In some embodiments, the control unit 902 is configured to: in a case where a variation range of the filtering parameter is less than or equal to a preset variation range each time within a preset number of times in succession, update the secondary path transfer function between the loudspeaker and the microphone according to the filtering parameter.

[0180] In some embodiments, the determination unit 901 is configured to: perform adaptive filtering processing on the loudspeaker excitation signal and the microphone detection signal based on an adaptive filtering algorithm to obtain the filtering parameter, in a case where at least one of the following conditions is met. The conditions include: the noise reduction signal is not present in the loudspeaker excitation signal, and a signal-to-noise ratio of the loudspeaker excitation signal and the microphone detection signal is greater than or equal to a second signal-to-noise ratio.

[0181] In some embodiments, the determination unit 901 is configured to: perform adaptive filtering processing on the loudspeaker excitation signal and the microphone detection signal in real time online based on an adaptive filtering algorithm to determine the filtering parameter.

[0182] In some embodiments, the control unit 902 is further configured to: perform noise reduction control based on the loudspeaker excitation signal, in a case where at least one of the following conditions is met. The conditions include: the noise reduction signal is present in the loudspeaker excitation signal, a signal-to-noise ratio of the loudspeaker excitation signal is less than a first signal-to-noise ratio, and a frequency of the loudspeaker excitation signal is greater than a preset frequency.

[0183] In some embodiments, the noise reduction device 900 provided by some embodiments of the present disclosure further includes an acquisition unit and a generation unit. The acquisition unit is configured to acquire a noise reference signal and a cabin sound source signal in real time through a sensor; and the generation unit is configured to generate a loudspeaker excitation signal based on the noise reference signal and the cabin sound source signal.

[0184] In some embodiments, the generation unit is configured to: perform noise reduction processing on the noise reference signal to obtain a noise reduced signal, and synthesize the noise reduced signal and the cabin sound source signal into the loudspeaker excitation signal.

[0185] In some embodiments, the acquisition unit is further configured to: acquire, in real time, a sound signal in the cabin through the microphone to obtain a microphone detection signal.

[0186] In the noise reduction device provided by some embodiments of the present disclosure, the matching degree of the secondary channel parameters and the noise reduction parameters can affect the active noise reduction effect. Therefore, according to the loudspeaker excitation signal and the microphone detection signal in the actual vehicle cabin, some embodiments of the present disclosure determine the change parameter of the secondary channel in the current vehicle cabin, determine the noise reduction parameter according to the change parameter, so that the updated noise reduction parameter matches the actual secondary channel, and thus the noise reduction control according to the updated noise reduction parameter can improve the noise reduction effect.

[0187] As to the device in the above-mentioned embodiments, the operation modes of each module in the device have been described in the embodiments of the method, and will not be described in detail here.

[0188] FIG. 10 is a block diagram of an electronic device according to some embodiments of the present disclosure. As shown in FIG. 10, the electronic device 1000 includes, but is not limited to, a processor 1001 and a memory 1002.

[0189] The memory 1002 is configured to store executable instructions of the processor 1001. It can be understood that the processor 1001 is configured to execute the instructions to implement the noise reduction method in the above-mentioned embodiments.

[0190] It should be noted that those skilled in the art can understand that the structure of the electronic device shown in FIG. 10 does not constitute a limitation on the electronic device, and the electronic device can include more or fewer components than those shown in FIG. 10, or combine certain components, or different component arrangements.

[0191] The processor 1001 is the control center of the electronic device, which connects each part of the electronic device through various interfaces and lines, executes at least one of the software programs or modules stored in the memory 1002, and calls the data stored in the memory 1002, to perform various functions of the electronic device and process data, thereby overall monitoring the electronic device. The processor 1001 can include one or more processing units. For example, the processor 1001 can integrate an application processor and a modem processor, the application processor mainly processes the operating system, user interface and application programs, and the modem processor mainly processes wireless communication. It can be understood that the above-mentioned modem processor can also not be integrated into the processor 1001.

[0192] The memory 1002 can be used to store software programs and various data. The memory 1002 can mainly include a program storage area and a data storage area. The program storage area can store an operating system, application programs (such as a determination unit, a processing unit, etc.) required by at least one function module, and the like. In addition, the memory 1002 can include a high-speed random access memory, and can also include a non-volatile memory, for example, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state memory device.

[0193] Some embodiments of the present disclosure further provide a computer readable storage medium including instructions, for example, the memory 1002 including instructions, which can be executed by the processor 1001 of the electronic device 1000 to implement the noise reduction method in the above embodiments.

[0194] In actual implementation, the steps performed by the determination unit 901 and the control unit 902 in FIG. 9 can be implemented by the processor 1001 in FIG. 10 invoking the computer program stored in the memory 1002. The execution process can refer to the description of the method part in the above embodiments, which will not be described here.

[0195] In some embodiments, the computer readable storage medium can be a non-transitory computer readable storage medium. For example, the non-transitory computer readable storage medium can be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, and an optical data storage device, etc.

[0196] Embodiments of the present disclosure further provide a vehicle 2000 including a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor executes the computer program to complete the noise reduction method in the above embodiments.

[0197] In actual implementation, as shown in FIG. 11, the vehicle 2000 further includes an engine, an electronic device, and a power amplifier, and the memory and the processor are integrated in at least one of the electronic device or the power amplifier to reduce the noise of the engine.

[0198] Some embodiments of the present disclosure further provide a computer program product including one or more instructions executable by the processor 1001 of the electronic device to complete the noise reduction method in the above embodiments.

[0199] It should be noted that the instructions in the above computer-readable storage medium or one or more instructions in the computer program product are executed by the processor of the electronic device to implement each process of the above method embodiments, and the same technical effects as the above method can be achieved. To avoid repetition, it will not be described here.

[0200] Through the description of the above embodiments, those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above division of functional modules is taken as an example, and in actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete the above-described full classification or part of the function.

[0201] In several embodiments provided by the present disclosure, it should be understood that the disclosed apparatus and method can be implemented by other means. For example, the above-described device embodiments are only illustrative, for example, the division of modules or units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another device, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed units can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0202] The units described as separate components can or can not be physically separate, and the components shown as units can be one physical unit or multiple physical units, that is, they can be located in one place or distributed to multiple different places. Part or all of the units can be selected according to actual needs to achieve the purpose of the present disclosure scheme.

[0203] In addition, each functional unit in each embodiment of the present disclosure can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0204] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a readable storage medium. Based on such understanding, the technical solutions of some embodiments of the present disclosure or the part that contributes to the related art or the whole classification or part of the technical solutions can be embodied in the form of a software product stored in a storage medium, including a plurality of instructions for causing an apparatus (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute the whole classification or part of the steps of the method of various embodiments of the present disclosure. The aforementioned storage medium includes: a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk, and various media that can store program codes.

[0205] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present disclosure, which should be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A method for noise reduction, comprising: determining a variation parameter of a secondary path based on a loudspeaker excitation signal and a microphone detection signal; determining a noise reduction parameter and performing noise reduction control according to the variation parameter.

2. The method of claim 1, wherein, The determining the noise reduction parameter and performing noise reduction control according to the variation parameter comprises: updating a secondary path transfer function between a loudspeaker and a microphone according to the variation parameter; updating the noise reduction parameter based on the updated secondary path transfer function; performing noise reduction control based on the updated noise reduction parameter.

3. The method of claim 2, wherein, The determining the variation parameter of the secondary path based on the loudspeaker excitation signal and the microphone detection signal comprises: determining a period delay parameter and a phase delay parameter based on the loudspeaker excitation signal and the microphone detection signal, the period delay parameter being used to represent a number of periods of a phase difference between the microphone detection signal and the loudspeaker excitation signal, and the phase delay parameter being used to represent a phase value of the phase difference between the microphone detection signal and the loudspeaker excitation signal.

4. The method of claim 3, wherein, The determining the period delay parameter and the phase delay parameter based on the loudspeaker excitation signal and the microphone detection signal comprises: determining the period delay parameter according to a coherence of the loudspeaker excitation signal and the microphone detection signal in at least one of a time domain or a frequency domain; and determining the phase delay parameter according to a phase difference value of the loudspeaker excitation signal and the microphone detection signal in the frequency domain.

5. The method of claim 4, wherein, The determining the period delay parameter according to the coherence of the loudspeaker excitation signal and the microphone detection signal in at least one of the time domain or the frequency domain comprises: determining the period delay parameter according to the coherence of the loudspeaker excitation signal and the microphone detection signal in at least one of the time domain or the frequency domain, in a case where at least one of the following conditions is met; the conditions comprising: the loudspeaker excitation signal is free of a noise reduction signal; a signal-to-noise ratio of the loudspeaker excitation signal and a noise signal is greater than or equal to a first signal-to-noise ratio; a frequency of the loudspeaker excitation signal is less than or equal to a preset frequency.

6. The method of any one of claims 3 to 5, wherein, The updating the secondary path transfer function between the loudspeaker and the microphone according to the variation parameter comprises: determining a signal delay duration between the microphone detection signal and the loudspeaker excitation signal based on the period delay parameter and the phase delay parameter; and updating the secondary path transfer function between the loudspeaker and the microphone based on the signal delay duration.

7. The method of claim 6, wherein, The updating the secondary path transfer function between the loudspeaker and the microphone based on the signal delay duration comprises: adjusting a signal delay duration of the secondary path transfer function between the loudspeaker and the microphone by using the signal delay duration between the microphone detection signal and the loudspeaker excitation signal, to update the secondary path transfer function between the loudspeaker and the microphone.

8. The method of claim 7, wherein, The adjusting the signal delay time length of the secondary channel transfer function between the loudspeaker and the microphone based on the signal delay time length between the microphone detection signal and the loudspeaker excitation signal comprises: Upsampling the secondary channel transfer function between the loudspeaker and the microphone to identify the signal delay time length of the secondary channel transfer function between the loudspeaker and the microphone; Adjusting the signal delay time length of the secondary channel transfer function between the loudspeaker and the microphone based on the signal delay time length between the microphone detection signal and the loudspeaker excitation signal; Downsampling the adjusted secondary channel transfer function between the loudspeaker and the microphone to update the secondary channel transfer function between the loudspeaker and the microphone.

9. The method according to any one of claims 3 to 8, wherein, The determining the periodic delay parameter and the phase delay parameter based on the loudspeaker excitation signal and the microphone detection signal comprises one of: Determining the periodic delay parameter and the phase delay parameter based on the loudspeaker excitation signal and the microphone detection signal in real time; or Determining the periodic delay parameter and the phase delay parameter based on the loudspeaker excitation signal and the microphone detection signal at a preset time interval.

10. The method of claim 2, wherein, The determining the change parameter of the secondary channel based on the loudspeaker excitation signal and the microphone detection signal comprises: Adaptive filtering processing the loudspeaker excitation signal and the microphone detection signal based on an adaptive filtering algorithm to obtain a filtering parameter.

11. The method of claim 10, wherein, The adaptive filtering processing the loudspeaker excitation signal and the microphone detection signal based on the adaptive filtering algorithm to obtain the filtering parameter comprises: Filtering the loudspeaker excitation signal based on the adaptive filtering algorithm to obtain an analog microphone detection signal; Determining an error signal between the analog microphone detection signal and the microphone detection signal; Determining the filtering parameter based on the loudspeaker excitation signal and the error signal.

12. The method of claim 11, wherein, The updating the secondary channel transfer function between the loudspeaker and the microphone according to the change parameter comprises: In a case where a change range of the filtering parameter each time in a continuous preset number of times is less than or equal to a preset change range, updating the secondary channel transfer function between the loudspeaker and the microphone according to the filtering parameter.

13. The method of any one of claims 10 to 12, wherein, The adaptive filtering processing the loudspeaker excitation signal and the microphone detection signal based on the adaptive filtering algorithm to obtain the filtering parameter comprises: In a case where at least one of the following conditions is met, the adaptive filtering processing the loudspeaker excitation signal and the microphone detection signal based on the adaptive filtering algorithm to obtain the filtering parameter; the conditions comprise: There is no noise reduction signal in the loudspeaker excitation signal; A signal-to-noise ratio of the loudspeaker excitation signal and the microphone detection signal and a noise signal is greater than or equal to a second signal-to-noise ratio.

14. The method according to any one of claims 10 to 13, wherein, The adaptive filter algorithm is used to perform adaptive filtering on the loudspeaker excitation signal and the microphone detection signal to obtain the filter parameter, including: Based on the adaptive filter algorithm, the loudspeaker excitation signal and the microphone detection signal are adaptively filtered in real time online to determine the filter parameter.

15. The method of any one of claims 1-14, further comprising: Based on the loudspeaker excitation signal, noise reduction control is performed when at least one of the following conditions is met; The conditions include: There is a noise reduction signal in the loudspeaker excitation signal; The signal-to-noise ratio of the loudspeaker excitation signal and the noise signal is less than a first signal-to-noise ratio; The frequency of the loudspeaker excitation signal is greater than a preset frequency.

16. The method of any one of claims 1-15, further comprising: Real-time acquisition of a noise reference signal by a sensor, and real-time acquisition of a cabin sound source signal; Based on the noise reference signal and the cabin sound source signal, the loudspeaker excitation signal is generated.

17. The method of claim 16, wherein, The noise reference signal is processed to obtain a noise reduction signal; The noise reduction signal and the cabin sound source signal are combined to obtain the loudspeaker excitation signal.

18. The method of any one of claims 1-17, further comprising: Real-time collection of sound signals in the cabin by a microphone to obtain the microphone detection signal.

19. A noise reduction device, comprising: A determination unit configured to determine a change parameter of a secondary channel based on a loudspeaker excitation signal and a microphone detection signal; and A control unit configured to determine a noise reduction parameter and perform noise reduction control according to the change parameter. The reference signal acquisition module, the secondary channel filtering module, the active noise control module, the noise reduction signal generation module, the adaptive filter, the loudspeaker and the microphone, the noise reduction system is configured to perform the noise reduction method according to any one of claims 1-18 to realize the noise control function.

21. The noise reduction system of claim 20, wherein 20. A noise reduction system comprising: The reference signal acquisition module is configured to acquire a noise reference signal; The secondary channel filtering module is configured to filter the noise reference signal to obtain a filtered noise reference signal; The active noise control module is configured to update the noise reduction parameter in the noise reduction signal generation module; The noise reduction signal generation module is configured to perform noise reduction processing on the noise reference signal according to the noise reduction parameter to generate an active noise reduction signal; The adaptive filter is configured to filter the cabin sound source signal to obtain a filtered cabin sound source signal; The loudspeaker is configured to output a loudspeaker excitation signal synthesized by the cabin sound source signal and the active noise reduction signal; The microphone is configured to measure the cabin sound signal to obtain the microphone detection signal. The cabin sound source module, the scene detection module, the delay estimation module and the secondary channel delay matching module realize the secondary channel delay estimation function. ​ 22. The noise reduction system of claim 20 or 21, further comprising: ​ 23. The noise reduction system of claim 22, wherein, the cabin sound source module is configured to generate the cabin sound source signal; the scene detection module is configured to detect the loudspeaker excitation signal; the delay estimation module is configured to perform secondary path delay estimation according to the loudspeaker excitation signal and the microphone detection signal, to obtain a secondary path delay; the secondary path delay matching module is configured to update the secondary path transfer function according to the secondary path delay.

24. The noise reduction system of claim 20 or 21, further comprising: a cabin sound source module, a signal detection module and an online secondary path estimation module to implement the online secondary path identification function.

25. The noise reduction system of claim 24, wherein, the cabin sound source module is configured to generate the cabin sound source signal; the signal detection module is configured to detect the loudspeaker excitation signal; the online secondary path estimation module is configured to: perform adaptive filtering processing according to the loudspeaker excitation signal and the microphone detection signal, to obtain filtering parameters; update the secondary path transfer function according to the filtering parameters.

26. An electronic device comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to execute the instructions to implement the method of any one of claims 1 to 18.

27. A vehicle comprising: a memory, a processor and a computer program stored on the memory and executable on the processor, the processor executing the program to implement the method of any one of claims 1 to 18.

28. The vehicle of claim 27, further comprising: an engine, a power amplifier, and the electronic device of claim 26, the memory and the processor being integrated in at least one of the electronic device or the power amplifier to reduce the noise of the engine.

29. A computer readable storage medium having stored therein instructions, wherein, when the computer executes the instructions, the computer executes the method of any one of claims 1 to 18.

30. A computer program product comprising instructions which, when executed on a computer, cause the computer to perform the method of any one of claims 1 to 18.

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