Active noise reduction method and system, storage medium, electronic equipment and vehicle

Abstract

The invention relates to an active noise reduction method and system, a storage medium, electronic equipment and a vehicle. The method comprises the steps that operation parameters of an air conditioning device on the vehicle and a first error signal collected through a preset sensor are obtained; reading noise signals corresponding to the operation parameters of the air conditioning device from a preset database as reference signals; determining a filter coefficient based on the reference signal and the first error signal; and processing the reference signal based on the filtering coefficient to obtain a control signal and playing the control signal so as to perform noise reduction on the reference signal. According to the method, by establishing the corresponding relation between the operation condition of the air conditioning device and the noise signal and combining the virtual microphone technology, noise reduction can be conducted under the condition that a reference microphone and a microphone at the target position are not installed, the cost is effectively reduced, and equipment installation is simplified.

Description

Technical Field

[0001] The present application relates to the field of audio processing technology, and in particular to an active noise reduction method, system, storage medium, electronic device and vehicle. Background Art

[0002] Vehicles usually use active noise reduction (ANC) technology to reduce ambient noise in the vehicle cabin. In vehicles, the noise of the air conditioning system is one of the main factors affecting passenger comfort, especially when driving at high speed or stationary, the noise of the air conditioning fan will directly affect the passenger's riding experience.

[0003] In the related art, when noise reduction is performed on the air conditioning system, a reference microphone is usually installed in the air conditioning box and an error microphone is installed at a target position inside the vehicle compartment to reduce the noise entering the passenger's ears. This system not only increases the cost of the system, but also increases the complexity of assembly. Summary of the invention

[0004] The embodiments of the present application provide an active noise reduction method, system, storage medium, electronic device and vehicle to simplify the installation of equipment on the vehicle and improve the noise reduction effect in the vehicle.

[0005] In order to achieve the above object, according to a first aspect of the present application, an active noise reduction system is provided. The method is applied to a vehicle, and the method comprises:

[0006] Acquiring operating parameters of the air conditioning device on the vehicle and a first error signal collected by a preset sensor;

[0007] Reading a noise signal corresponding to the operating parameters of the air conditioner from a preset database as a reference signal;

[0008] determining a filter coefficient based on the reference signal and the first error signal;

[0009] The reference signal is processed based on the filter coefficient to obtain a control signal and play it to reduce noise on the reference signal.

[0010] Optionally, the operating parameters include at least one of wind speed level, air outlet position, wind direction, and operating mode.

[0011] Optionally, determining a filter coefficient based on the reference signal and the first error signal includes:

[0012] Based on the acquisition position and the target position of the first error signal, the first error signal is processed to obtain a second error signal of the target position;

[0013] The filter coefficient is determined based on the second error signal and the reference signal.

[0014] Optionally, the processing of the first error signal based on the acquisition position and the target position of the first error signal to obtain a second error signal of the target position includes:

[0015] Determining a first expected noise signal at the acquisition position based on the first error signal and a preset control signal;

[0016] Determining a second expected noise signal at the target location based on the first expected noise signal;

[0017] The second error signal is determined based on the second expected noise signal and the preset control signal.

[0018] Optionally, determining the first expected noise signal at the acquisition position based on the first error signal and a preset control signal includes:

[0019] filtering the preset control signal based on a first transfer function to obtain a first preset control signal, wherein the first transfer function is an acoustic transfer function from the playback device to the collection position;

[0020] The first expected noise signal is obtained based on the difference between the first error signal and the first preset control signal.

[0021] Optionally, determining a second expected noise signal at the target location based on the first expected noise signal includes:

[0022] The first expected noise signal is filtered based on a second transfer function to obtain a second expected noise signal at the target position, wherein the second transfer function is an acoustic transfer function from the acquisition position to the target position.

[0023] Optionally, determining the second error signal based on the second expected noise signal and the preset control signal includes:

[0024] filtering the preset control signal based on a third transfer function to obtain a second preset control signal, wherein the third transfer function is an acoustic transfer function between the playback device and the target position;

[0025] The second error signal is obtained based on the sum of the second expected noise signal and the second preset control signal.

[0026] Optionally, the method further comprises:

[0027] The reference signal at the current moment is processed according to the filter coefficient obtained at each moment to obtain the control signal at the current moment as the preset control signal.

[0028] Optionally, determining the filter coefficient based on the second error signal and the reference signal includes:

[0029] Determining an update value based on the reference signal, the second error signal and a preset step size;

[0030] The preset filter coefficient is updated based on the update value to obtain the updated filter coefficient.

[0031] Optionally, determining the update value based on the reference signal, the second error signal and a preset step size includes:

[0032] Filtering the reference signal based on a third transfer function to obtain a filtered reference signal;

[0033] The update value is determined based on the filtered reference signal, the second error signal and a preset step size.

[0034] Optionally, determining the update value based on the filtered reference signal, the second error signal and a preset step size includes:

[0035] Obtaining an update step size based on a ratio of the preset step size to the power of the reference signal;

[0036] The update value is obtained based on the product of the filtered reference signal, the second error signal and the update step size.

[0037] Optionally, updating the preset filter coefficient based on the update value to obtain the updated filter coefficient includes:

[0038] The filter coefficient at the current moment is updated according to the update value obtained at each moment to obtain the updated filter coefficient at the next moment.

[0039] Optionally, the method further comprises:

[0040] Based on the sample noise signal, determining a sample reference signal;

[0041] Determine a sample error signal based on a signal collected by a sensor at a preset position;

[0042] determining sample filter coefficients based on the sample reference signal and the sample error signal;

[0043] Based on the sample filter coefficients, a sample transfer function is determined.

[0044] Optionally, the preset position includes the acquisition position and / or the target position, and correspondingly, the sample transfer function is one of a first transfer function, a second transfer function and a third transfer function.

[0045] According to the second aspect of the present application, an embodiment of the present application further provides an active noise reduction system, the system comprising:

[0046] A sound collection module, wherein the sound collection module includes a preset sensor for collecting a first error signal;

[0047] Noise control modules for:

[0048] Acquiring operating parameters of the air conditioning device on the vehicle and a first error signal collected by a preset sensor;

[0049] Reading a noise signal corresponding to the operating parameters of the air conditioner from a preset database as a reference signal;

[0050] determining a filter coefficient based on the reference signal and the first error signal;

[0051] Processing the reference signal based on the filter coefficient to obtain a control signal and play the control signal to reduce noise on the reference signal;

[0052] The playing device is used for receiving and playing the control signal.

[0053] According to a third aspect of the present application, an embodiment of the present application further provides a computer-readable storage medium on which a computer program is stored, and the computer storage medium stores instructions, which, when executed by a computer, enable the computer to implement any one of the active noise reduction methods provided in the embodiments of the present application.

[0054] According to a fourth aspect of the present application, an embodiment of the present application further provides an electronic device, including:

[0055] a memory having a computer program stored thereon;

[0056] A processor is used to execute the computer program in the memory to implement any one of the active noise reduction methods provided in the embodiments of the present application.

[0057] According to a fifth aspect of the present application, an embodiment of the present application further provides a vehicle, comprising the active noise reduction system.

[0058] Some embodiments of the present specification include at least the following beneficial effects: by establishing a correspondence between the operating conditions of the air-conditioning device and the noise signal, and combining the virtual microphone technology, noise reduction can be performed without installing a reference microphone and a microphone at a target position, which can effectively reduce costs, simplify the installation of equipment on the vehicle, and improve the noise reduction effect in the vehicle. At the same time, it saves space for arranging microphones, reduces processing and operation difficulties, and improves the noise reduction effect of the algorithm.

[0059] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0061] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0062] Figure 1 is a schematic diagram of the structure of an active noise reduction system according to some embodiments of this specification;

[0063] Figure 2 is an exemplary flow chart of an active noise reduction method according to some embodiments of this specification;

[0064] Figure 3 is an exemplary flow chart of determining filter coefficients according to some embodiments of this specification;

[0065] Figure 4 is an exemplary schematic diagram of a virtual microphone technology according to some embodiments of the present specification;

[0066] Figure 5 is an exemplary schematic diagram of active noise reduction effect according to some embodiments of this specification;

[0067] Figure 6 is an exemplary schematic diagram of a preset database according to some embodiments of this specification;

[0068] Figure 7 It is a schematic diagram of the structure of an electronic device according to some embodiments of this specification. DETAILED DESCRIPTION

[0069] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0070] In order to facilitate understanding of the implementation scheme provided in the embodiment of the present application, the relevant application background of the in-vehicle active noise reduction system provided in the embodiment of the present application is first described.

[0071] At present, vehicle-mounted air conditioning devices generate various types of noise during operation, and the spectrum and intensity of these noises will change with the working mode of the air conditioner (such as cooling, heating, ventilation, etc.). Traditional noise control methods often rely on arranging multiple reference microphones near the air conditioning device to monitor the noise signal in real time, and use these signals to generate corresponding cancellation signals. However, this method has problems such as high cost and complex installation. In addition, the effective noise reduction area of ​​the traditional ANC system is mainly concentrated around the error sensor, and the noise reduction range is very small, so the error sensor must be installed at the target position (such as near the human ear) to improve the noise reduction effect, but such an installation will limit the movement of the human head.

[0072] In view of this, some embodiments of the present specification provide an active noise reduction system and method, which can effectively reduce costs, simplify equipment installation on the vehicle, improve the noise reduction effect in the vehicle, and improve the noise reduction performance of the system by establishing a correspondence between the operating conditions of the air-conditioning device and the noise signal, and combining virtual microphone technology.

[0073] Figure 1 It is a schematic diagram of the structure of an active noise reduction system according to some embodiments of this specification.

[0074] like Figure 1 As shown, the active noise reduction system 100 may include a noise control module 111 , a sound collection module 112 and a playback device 113 .

[0075] The noise control module 111 processes information and / or data related to the active noise reduction system 100. In some embodiments, the noise control module 111 can obtain information and / or data from the storage module, such as a reference signal.

[0076] The current active noise reduction technology requires the installation of a reference microphone at or near the location of the air conditioner, which increases the cost and increases the time for signal feedback, reducing the noise reduction effect. In some embodiments, the noise control module 111 can retrieve the corresponding reference signal from the preset database based on the current operating parameters of the air conditioner, and perform signal processing based on the reference signal to determine the control signal for achieving noise elimination. For more information about this embodiment, please refer to Figure 2 . Exemplarily, the control signal may be an electrical signal, an analog signal or a digital signal, which is not limited in the present application. In some embodiments, the noise control module 111 may include one or more sub-processing devices (e.g., a single-core processing device or a multi-core multi-core processing device). As an example only, such as a central processing unit (CPU), an application-specific integrated circuit (ASIC), a digital signal processor (DSP), etc. or any combination thereof. In some embodiments, the noise control module 111 may be integrated or included in a vehicle.

[0077] In some embodiments, the hardware of the noise control module 111 may be implemented as a vehicle controller or a component in the vehicle controller. The deployment position of the noise control module 111 in the vehicle may not be limited.

[0078] In some embodiments, the sound collection module 112 is connected to the noise control module 111. The sound collection module 112 is an acoustic sensor, which can be deployed in the target area to collect error signals of the target area (e.g., the user's ear) at each moment. The error signal can reflect the noise elimination effect of the target area.

[0079] In some application scenarios, the error microphone cannot be placed at the desired target position (target active quiet zone). For example, the application of wireless Bluetooth headsets makes it impossible to place the microphone at the periosteum of the human ear where an active quiet zone is desired, which greatly reduces the noise reduction effect in the car.

[0080] In some embodiments, the sound collection module 112 may include a first sensor, and the first sensor (also called a physical microphone) may be set at a location that is easy to install or where other hardware is already installed in the vehicle itself. For example, the first sensor may be installed at a location such as a door. In some embodiments, the sound collection module 112 may also include a second sensor, and the second sensor (also called a virtual microphone) is used to be placed at a desired noise reduction position at a certain time stage (e.g., a training stage).

[0081] In some embodiments, during the training phase, the noise control module 111 models the transfer function between the virtual microphone and the physical microphone, wherein the physical microphone is located closer to the playback device 113 and farther from the target active quiet zone (ZoQ). During the control phase, when no microphone is placed in the target active quiet zone, the adaptive control filter achieves noise reduction at the target active quiet zone based on the real-time output of the physical microphone and the prior information of the transfer function obtained during the training phase.

[0082] The training phase is the phase in which each transmission path in the adaptive filter is modeled. All prior information obtained in the training phase, including transfer functions and noise characteristics, will be used in the control phase to compensate for the impact of the physical path and ensure effective noise control in the target active quiet zone. The control phase is the phase in which the noise at the target location is actually reduced.

[0083] In some embodiments, the noise control module 111 sends the control signal to the playback device 113. The playback device 113 plays the control signal to generate a sound wave signal, which cancels the noise in the target area to achieve noise elimination. The target area may be the area where the user's ear is located, and the target area may be determined based on a pre-estimated position range of the user's ear.

[0084] The vehicle may be an intelligent vehicle, such as an autonomous driving vehicle that realizes all functions as automatic control, or an assisted driving vehicle that realizes some functions as automatic control to provide driving assistance, or may be an ordinary vehicle. In some embodiments, the vehicle may be a fuel vehicle, a hybrid vehicle, an electric vehicle, etc.

[0085] The hardware of the playback device 113 may be a hardware device for audio playback. In some embodiments, the playback device 113 may be integrated or included in the vehicle, or may be another independent device in the active noise reduction system. For example, the playback device 113 may include a speaker, a loudspeaker, etc. In some embodiments, the playback device 113 may include one or more vehicle-mounted speakers.

[0086] In some embodiments, the playback device 113 may be installed in various areas, each of which includes one or more audio devices (eg, speakers).

[0087] In some embodiments, the playback device 113 may include one or more. In order to achieve a better noise reduction effect, the playback device 113 may be deployed in a target area, that is, close to the user's ears. When the playback device 113 is deployed in the target area, it may include: a playback device deployed on a seat headrest, and / or a playback device deployed on a seat backrest.

[0088] It should be noted that the above-mentioned user can be a user sitting in any seat position in the vehicle, for example, the user can sit in the main driver's seat, the co-pilot seat or the back seat. Accordingly, the target area can include the area where the ear position of the user sitting in any seat position is located. That is, the playback device 113 can be deployed for some or all of the users who can sit in the vehicle cabin. For example, the playback device 113 can be deployed in at least one of the following areas: the area where the ear position of the main driver is located, the area where the ear position of the co-pilot is located, or the area where the ear position of any user sitting in the back seat is located.

[0089] In some embodiments, the playback device 113 may also be deployed under a seat or in a trunk.

[0090] The playback device 113 is deployed to achieve noise reduction control, or the playback device 113 can reuse an existing playback device in the vehicle. For example, the playback device 113 can reuse a full-frequency playback device in the vehicle.

[0091] In some embodiments, the playback device 113 may be independent of the active noise reduction system 100. The active noise reduction system 100 is connected to the playback device 113 deployed in the vehicle and sends a control signal to the playback device 113. The playback device 113 plays the control signal to generate a sound wave signal to achieve noise cancellation.

[0092] In some embodiments, the noise control module 111, the playback device 113, and the sound collection module 112 can be controlled and information data can be exchanged through a bus, where the bus includes but is not limited to an in-vehicle audio bus (Audio Bus, A2B), a serial port, SPI, CAN, Bluetooth, etc. For example, the noise control module 111, the playback device 113, and the sound collection module 112 can be connected based on A2B.

[0093] In some embodiments, the active noise reduction system can be applied to multiple scenarios where local noise control is required. For example, in a vehicle interior, the active noise reduction system creates a target active quiet zone around the driver's seat to reduce transmitter noise, road noise and wind noise. The active noise reduction system can also be applied to aircraft cabins, conference rooms or offices, and home theaters.

[0094] It should be noted that the above description of the active noise reduction system and its modules is only for convenience of description and does not limit this specification to the scope of the embodiments. It is understandable that for those skilled in the art, after understanding the principle of the system, it is possible to arbitrarily combine the modules or form a subsystem to connect with other modules without deviating from this principle. In some embodiments, Figure 1The noise control module 111, the sound collection module 112, and the playback device 113 disclosed in the specification can be different modules in a system, or a module can realize the functions of two or more modules mentioned above. For example, each module can share a storage module, or each module can have its own storage module. Such variations are all within the protection scope of this specification.

[0095] Figure 2 is an exemplary flow chart of an active noise reduction method according to some embodiments of this specification. In some embodiments, process 200 can be executed based on a noise control module of an active noise reduction system. Figure 2 As shown, process 200 includes the following steps:

[0096] Step S210, obtaining operating parameters of the air conditioning device on the vehicle and a first error signal collected by a preset sensor.

[0097] An air conditioning device refers to a system or equipment used to regulate the air temperature, humidity, cleanliness, air flow rate, etc. in a space.

[0098] Operating parameters refer to the various set values ​​that can be adjusted when the air conditioner is in working condition.

[0099] The preset sensor refers to a sound collection module that is arranged at a position far away from the target active quiet zone (ZoQ). For example, the preset sensor may be the first sensor.

[0100] For more information about the sound collection module and the first sensor, see Figure 1 Related description.

[0101] The first error signal refers to an error signal at a preset sensor location.

[0102] It should be understood that different positions correspond to different error signals.

[0103] The error signal is the difference between the reference signal transmitted to a certain location and the control signal output by the adaptive filter.

[0104] The error signal reflects the difference between the control signal output by the adaptive filter and the reference signal at the corresponding position. By minimizing the error signal, the output signal of the adaptive filter can be made closer to the reference signal.

[0105] In some embodiments, the first error signal can be obtained in a variety of ways. For example, the noise control module can be connected to a preset sensor for communication. The noise control module can obtain the first error signal under certain circumstances (e.g., in real time, at intervals, or triggered under certain circumstances, etc.).

[0106] In some embodiments, the operating parameters include at least one of wind speed level, air outlet position, wind direction, and operating mode.

[0107] The wind speed gear refers to the adjustment setting of the wind speed of the air conditioner. In some embodiments, the wind speed gear may include low speed (Low), medium speed (Medium) and high speed (High), and the wind speed gear may also be represented by numbers 1, 2, 3, etc. The user may select a suitable wind speed gear as needed.

[0108] The air outlet position refers to the position setting of the air outlet of the air conditioning device. In some embodiments, the air outlet position includes air outlets preset at different positions in the space. For example, the air outlet position on the vehicle includes the dashboard air outlet, the windshield defrost air outlet, the foot air outlet, etc.

[0109] Wind direction refers to the direction of the wind blown out by the air conditioning unit.

[0110] In some embodiments, air outlets at different positions are provided with adjustable blades, and the air conditioning device can adjust the wind direction and air volume by the direction of rotation of the adjustable blades.

[0111] In some embodiments, the wind direction may include left blowing, right blowing, upward blowing, and downward blowing.

[0112] The operation mode refers to the preset state of the air conditioning system under different conditions. In some embodiments, the operation mode includes a blowing mode, a circulation mode, etc.

[0113] Blowing mode refers to different air outlet modes preset in the air conditioning device. In some embodiments, the blowing mode may include blowing on the face, blowing on the feet, defrosting, etc.

[0114] The circulation mode refers to the air circulation mode preset by the air conditioning device. In some embodiments, the circulation mode includes internal circulation (circulating only the air in the room) and external circulation (introducing external air to mix with the indoor air).

[0115] Figure 6 It is an exemplary schematic diagram of a preset database shown in some embodiments of this specification.

[0116] like Figure 6 As shown, the preset data stores operating parameter combinations of different air-conditioning devices and corresponding noise signals.

[0117] In some embodiments, the operating parameters can be obtained in a variety of ways. For example, the noise control module can obtain the operating parameters through manual input and storage modules. For another example, the noise control module can communicate with the air conditioning device through a network inside the vehicle (such as a CAN (Controller Area Network) bus) to obtain information related to the operating parameters of the air conditioning.

[0118] In some embodiments of the present specification, the air conditioning device may generate different noise signals under different operating parameters. Acquiring the operating parameters of the air conditioning device at different times may help to obtain accurate noise signals later.

[0119] Step S220: Read a noise signal corresponding to the operating parameters of the air-conditioning device from a preset database as a reference signal.

[0120] The preset database is a database used to store, index and query vectors. The preset database can store multiple reference vectors and the reference noise signal corresponding to each reference vector. The reference vector is constructed from historical operating parameters.

[0121] The historical wind speed level, historical air outlet position, historical wind direction, historical blowing mode, and historical circulation mode that constitute the reference vector may be data at the same time point or time period.

[0122] A noise signal refers to an unwanted signal that interferes with the played audio signal. For example, the noise signal may include engine noise, road noise, or wind noise.

[0123] The reference signal is a signal related to the noise. For example, the reference signal is a noise signal obtained by direct measurement or a signal determined by synthesis.

[0124] In some embodiments, the reference signal can assist the adaptive sensor in performing adaptive adjustment and output a signal that is the same as or similar to the reference signal.

[0125] In some embodiments, a retrieval vector may be constructed based on the operating parameters of the current time period; a search may be performed in a preset database based on the retrieval vector to determine a target vector that meets the matching conditions, and a reference noise signal corresponding to the target vector may be used as a reference noise signal.

[0126] In some embodiments, a preset database may be constructed based on historical data. For example, based on historical data, a historical operating parameter of each historical time period may be determined as a reference vector, and a historical noise signal of the historical time period may be used as a reference noise signal corresponding to the reference vector. Further, the processor may construct a preset database based on multiple reference vectors and their corresponding reference noise signals.

[0127] The matching condition may refer to a judgment condition for determining a target vector. The matching condition may include that the vector distance from the search vector is less than a preset threshold, etc. There are many methods for calculating the vector distance, such as Euclidean distance, cosine distance, etc. The preset threshold may be a system preset value, a system default value, etc.

[0128] The current time period refers to a period of time before and after the current moment. The current moment is the moment when the reference signal and the error signal are obtained and the control signal is calculated and determined. The current moment can be any time point, depending on the time when the noise control module processes the relevant instructions.

[0129] Step S230: determining a filter coefficient based on the reference signal and the first error signal.

[0130] Filter coefficients refer to the parameters of the adaptive filter.

[0131] In some embodiments, the adaptive filter may be a FxLMS (Filtered-x Least Mean Square) adaptive filter or other similar adaptive filters.

[0132] In some embodiments, the filter coefficient can be determined in a variety of ways based on the reference signal and the first error signal collected by the preset sensor. For example, the filter coefficients at different times can be predicted by a prediction model based on the reference signal and the first error signal collected by the preset sensor set far away from the target position. The prediction model can be a machine learning model such as a trained neural network model. The input of the prediction model can include the reference signal and the first error signal collected by the preset sensor set far away from the target position, and the output can include the filter coefficients at each time. The prediction model can be trained based on a large number of labeled training samples through various feasible methods. For example, parameter update can be performed based on the gradient descent method. The training sample can include a sample reference signal and a sample first error signal. The training sample can be obtained based on historical data. The label can be the filter parameter at each time actually corresponding to the training sample, which can be obtained by manual or automatic annotation.

[0133] In some embodiments, based on the acquisition position and the target position of the first error signal, the first error signal is processed to obtain a second error signal at the target position; and based on the second error signal and a reference signal, a filter coefficient is determined.

[0134] The target location refers to a specific location or area where noise reduction control is required. For example, the target location can be the area where the driver is located, the center of the conference room, etc. The target location can be determined based on actual conditions.

[0135] In some embodiments, the target location is the location of the second sensor during the training phase.

[0136] For more information about the second sensor, see Figure 1 Related description.

[0137] The second error signal refers to an error signal of the predicted or estimated target position.

[0138] In some embodiments, the signal at the target position may be estimated in a variety of ways based on the first error signal to determine the second error signal. For example, the signal at the target position may be determined as the second error signal based on the first error signal collected by a preset sensor through manual analysis, theoretical calculation and / or modeling.

[0139] In some embodiments, the filter coefficient can be determined in a variety of ways based on the second error signal and the reference signal. For example, an adaptive filter designed using the FxLMS (Filtered-x Least Mean Square) algorithm, the reference signal is A(n), the second error signal is B(n), the reference signal A(n) is filtered through the third secondary path estimation filter to obtain the filtered reference signal A'(n), and the coefficient of the adaptive filter is updated through the coefficient iteration formula w(n+1)=w(n)+Δw(n), Δw(n)=μ×A'(n)×B(n), where w(n+1) is the updated filter coefficient, w(n) is the filter coefficient before the update, Δw(n) is the update value, and × represents the dot multiplication operation. The reference signal x(n) is filtered by the adaptive filter and the control signal y(n) is output.

[0140] The third secondary path refers to the sound transmission path from the location of the playback device to the target location of the control signal.

[0141] The third secondary path estimation refers to the mathematical model of the third secondary path established based on the characteristics of the third secondary path.

[0142] In some embodiments of the present specification, the filter coefficient is determined by using the second error signal and the reference signal, so that the error signal at the target position can be reduced in a targeted manner to meet the user's personalized noise reduction needs for different areas.

[0143] In some embodiments, a first expected noise signal at the acquisition position can be determined based on the first error signal and the preset control signal; a second expected noise signal at the target position can be determined based on the first expected noise signal; and a second error signal can be determined based on the second expected noise signal and the preset control signal.

[0144] The preset control signal refers to a control signal to be updated. For example, the preset control signal may be a control signal at the current time, or a control signal at any other time.

[0145] The control signal is the signal output by the adaptive filter.

[0146] The current time is the moment or time period when the reference signal and the second error signal are obtained and the control signal for the next time is calculated and determined. The current time can be any time point, depending on the time when the noise control module processes the relevant instructions.

[0147] The first expected noise signal refers to a predicted or estimated reference signal of a collection position (eg, the position of the first sensor).

[0148] The second expected noise signal refers to a predicted or estimated reference signal of the target position (eg, the second sensor).

[0149] In some embodiments, the expected noise signal at the acquisition position may be determined in a variety of ways based on the first error signal and the preset control signal. For example, the expected noise signal at the acquisition position may be determined based on the preset control signal through theoretical calculation, modeling, etc.

[0150] In some embodiments, the second expected noise signal at the target location may be determined in a variety of ways based on the first expected noise signal. For example, the expected noise signal at the acquisition location may be determined based on the first expected noise signal through theoretical calculation, modeling, and the like.

[0151] In some embodiments, the second error signal may be determined based on the second expected noise signal and the preset control signal in a variety of ways. For example, the second error signal may be determined based on the second expected noise signal and the preset control signal by theoretical calculation, modeling, and the like.

[0152] In some embodiments of the present specification, by using the actual noise signal detected by the first sensor as a reference and combining it with the control signal at the current moment to estimate the error signal at the second sensor, the noise situation in the actual environment can be more accurately reflected, which helps to accurately estimate the error signal at the location of the second sensor, and further helps the system to more accurately generate an anti-phase signal to offset the noise, thereby improving the noise control effect.

[0153] In some embodiments, the preset control signal can be filtered based on a first transfer function to obtain a first preset control signal, wherein the first transfer function is an acoustic transfer function from the playback device to the collection position; and the first expected noise signal is obtained based on the difference between the first error signal and the first preset control signal.

[0154] The first transfer function refers to a mathematical model of the first secondary path established based on the characteristics of the first secondary path.

[0155] The first secondary path refers to the acoustic transmission path from the playback device to the acquisition location.

[0156] The first preset control signal refers to a predicted or estimated signal of the preset control signal arriving at the collection location after being transmitted through the first secondary path.

[0157] In some embodiments, the first secondary path may cause attenuation, reflection, diffraction, etc. to the preset control signal.

[0158] In some embodiments, the first preset control signal may be determined based on the convolution of the first transfer function and the preset control signal; and the expected noise signal at the acquisition position may be determined based on the difference between the first error signal and the first preset control signal.

[0159] In some embodiments of the present specification, in an adaptive noise control (ANC) system, the characteristics of the secondary path directly affect the control effect. By using the transfer function of the first secondary path to filter the preset control signal, the influence of the first secondary path can be compensated, which helps to subsequently accurately estimate the error signal at the location of the second sensor.

[0160] In some embodiments, the first expected noise signal may be filtered based on a second transfer function to obtain a second expected noise signal at the target position, wherein the second transfer function is an acoustic transfer function from the acquisition position to the target position.

[0161] The second transfer function refers to a mathematical model of the second secondary path established based on the characteristics of the second secondary path.

[0162] The second secondary path refers to the acoustic transmission path from the acquisition location to the target location.

[0163] In some embodiments, the target location is the location or corresponding area where the second sensor is placed during the training phase.

[0164] In some embodiments, the second secondary path may cause attenuation, delay, etc. on the preset control signal.

[0165] In some embodiments, the first expected noise signal may be filtered in a variety of ways based on the second transfer function to obtain a second expected noise signal at the target location. For example, the second expected noise signal at the target location may be obtained based on the convolution of the second transfer function and the first expected noise signal.

[0166] In some embodiments of this specification, there is a certain distance between the first sensor and the second sensor, and the control signal at the current time will experience delay, attenuation, reflection, etc. when propagating in space. The characteristics of the transmission channel between the first sensor and the second sensor reflect the impact of these phenomena on the signal. By estimating the second transfer function, the second expected noise signal at the target position can more accurately reflect the situation in the actual environment, which is helpful for the subsequent accurate estimation of the error signal at the position of the second sensor.

[0167] In some embodiments, the preset control signal can be filtered based on a third transfer function to obtain a second preset control signal, wherein the third transfer function is an acoustic transfer function between the playback device and the target position; and the second error signal is obtained based on the sum of the second expected noise signal and the second preset control signal.

[0168] The third transfer function refers to a mathematical model of the third secondary path established based on the characteristics of the third secondary path.

[0169] The third secondary path refers to the acoustic transmission path from the playback device to the target location.

[0170] In some embodiments, the third secondary path may cause attenuation, delay, multipath effect, etc. to the preset control signal.

[0171] The second preset control signal refers to a predicted or estimated signal after the preset control signal reaches the target position after being transmitted through the third secondary path.

[0172] In some embodiments, the preset control signal may be filtered in a variety of ways based on the third transfer function to obtain the second preset control signal. For example, the second preset control signal may be obtained by convolution of the third transfer function and the preset control signal.

[0173] In some embodiments of the present specification, by estimating a virtual error signal at a desired target position (e.g., at the human ear) based on an actual error signal at the first sensor (e.g., somewhere on the door), the purpose of separating the noise reduction area from the error microphone is achieved. This helps to hide the error microphone, eliminates the need for additional installation in the seat, greatly reduces costs, and is beneficial to the overall layout of the vehicle.

[0174] In some embodiments, the reference signal at the current moment may be processed according to the filter coefficient obtained at each moment to obtain the control signal at the current moment as the preset control signal.

[0175] In some embodiments, the adaptive filter determines the control signal at the current moment as the preset control signal based on the convolution of the reference signal input at the current moment and the filter coefficient at the current moment.

[0176] In some embodiments, the adaptive filter processes the reference signal at each moment according to the filter coefficient obtained at that moment to obtain the control signal at that moment as the preset control signal at that moment.

[0177] Each moment may also be a sampling moment of a reference signal, or a sampling period in which the sampling moment of the reference signal is located. The reference signal is composed of signals sampled at multiple moments.

[0178] In some embodiments of the present specification, by estimating a virtual error signal at a desired target position (e.g., at the human ear) based on an actual error signal at the first sensor (e.g., somewhere on the door), the purpose of separating the noise reduction area from the error microphone is achieved. This helps to hide the error microphone, eliminates the need for additional installation in the seat, greatly reduces costs, and is beneficial to the overall layout of the vehicle.

[0179] Step S240: Process the reference signal based on the filter coefficient to obtain a control signal and play it to reduce noise on the reference signal.

[0180] The control signal is the signal output by the adaptive filter.

[0181] In some embodiments, the control signal is a signal that updates a preset control signal. For example, the preset control signal is the control signal at the current time; based on the control signal at the current time and a reference signal, an updated filter coefficient is determined; based on the updated filter coefficient, the reference signal is processed to obtain a control signal at the next time.

[0182] In some embodiments, the reference signal can be processed in a variety of ways according to the filter coefficient to obtain a control signal of the reference signal. For example, multiple rounds of iterations are performed to obtain a control signal based on the iteration results, wherein at least one round of iterations includes: inputting the reference signal and the second error signal of the current round of iterations into an adaptive filter to obtain an updated filter coefficient, filtering the reference signal based on the updated filter coefficient, such as calculating the convolution of the reference signal and the updated filter coefficient to obtain the control signal output by the current round of iteration; in response to the iteration condition being met, ending the iteration and using the output control signal as the iteration result; in response to the iteration condition not being met, playing the control signal output by the current round of iteration through a playback device, obtaining the reference signal and error signal of the next round of iteration, and continuing the next round of iteration.

[0183] The iteration condition is a judgment condition for evaluating whether the iteration is stopped. In some embodiments, the iteration condition may include that the number of iteration updates has reached a number threshold, the absolute value or square value of the error signal is less than a reference threshold, etc. The number threshold and the reference threshold may be a system default value, a system preset value, etc.

[0184] In some embodiments, the control signal may be sent to a playback device for playback.

[0185] In some embodiments, the playback device may receive a control signal sent by the noise control module via an in-vehicle audio bus (Audio Bus, A2B), and perform decoding and playback based on the received control signal.

[0186] In some embodiments of the present specification, by forming a complete database for storing noise information of common operating conditions of the air conditioner (for example, 3 wind speeds, internal circulation, refrigeration, full-open direct blowing, etc.), when the air conditioner is working under specific conditions, the noise signal is directly called from the database as a reference signal, and there is no need to use a reference microphone to measure the reference signal, thus avoiding the addition of reference microphone hardware and reducing costs. At the same time, it saves space for arranging the microphone, reduces processing and operation difficulty, and reduces signal feedback time, thereby improving the noise reduction effect of the algorithm.

[0187] In some embodiments, an update value may be determined based on the reference signal, the second error signal, and a preset step size, and the preset filter coefficient may be updated based on the update value to obtain an updated filter coefficient. For more information about this embodiment, see Figure 3 Related description.

[0188] Figure 3 is an exemplary flow chart of determining filter coefficients according to some embodiments of the present specification.

[0189] In some embodiments, process 300 may be performed based on a noise control module of an active noise reduction system. Figure 3 As shown, process 300 includes the following steps:

[0190] Step S310, determining an update value according to a reference signal, a second error signal and a preset step size.

[0191] For more information about the reference signal and the second error signal, see Figure 2 Related description.

[0192] The preset step size is used to control the magnitude of the update of the filter coefficients of the adaptive filter in each iteration.

[0193] In some embodiments, the preset step size may be a system default value, a system preset value, or a value determined according to actual conditions.

[0194] The update value refers to the increment or change of the filter coefficient in the time domain.

[0195] In some embodiments, the update value can be obtained in a variety of ways based on the reference signal, the second error signal and the preset step size. For example, the correlation between the reference signal and the second error signal can be calculated to obtain a correlation value, and the correlation value can be adjusted based on the preset step size to determine the update value. Exemplarily, different preset step sizes correspond to different adjustment scale coefficients, and the update value is determined based on the product of the adjustment scale coefficient and the correlation value. The correlation between the two signals can be determined by calculating a correlation function. Different preset step sizes correspond to different adjustment scale coefficients, and the corresponding relationship can be determined based on prior knowledge or historical data.

[0196] In some embodiments, the update value may be determined based on the reference signal and the second error signal. For example, the update value may be positively correlated with the product of the reference signal and the second error signal.

[0197] In some embodiments, the reference signal may be filtered based on a third transfer function to obtain a filtered reference signal; and the update value may be determined based on the filtered reference signal, the second error signal and a preset step size.

[0198] In some embodiments, a filtered reference signal may be obtained based on the convolution of the third transfer function and the reference signal.

[0199] In some embodiments, the update value may be determined in a variety of ways based on the filtered reference signal, the second error signal, and the preset step size. For example, a correlation value may be obtained based on the product of the filtered reference signal and the second error signal, and the correlation value may be adjusted based on the preset step size to determine the update value. For another example, the update value may be determined based on the product of the filtered reference signal, the second error signal, and the preset step size.

[0200] In some embodiments of the present specification, by considering the influence of the transmission path between the playback device and the target location, the influence of the transmission path on the signal can be compensated, so that the generated filter coefficients are more accurate.

[0201] In some embodiments, the update step size may be obtained based on the ratio of the preset step size to the power of the reference signal; and the update value may be obtained based on the product of the filtered reference signal, the second error signal and the update step size.

[0202] The update step size is the result of adjusting the preset step size.

[0203] In some embodiments of the present specification, the step size is determined by the ratio of the preset step size to the power of the reference signal, which can significantly improve the performance of the adaptive filter and dynamically adjust the step size so that the adaptive filter can maintain a good convergence speed under the characteristics of different reference signals, avoid system divergence, and improve the stability of the noise reduction system.

[0204] Step S320, updating the preset filter coefficient according to the update value to obtain the updated filter coefficient.

[0205] For more information about filter coefficients, see Figure 2 Related description.

[0206] The preset filter coefficient refers to the filter coefficient to be updated. For example, the preset filter coefficient may be the filter coefficient at the current time, or the preset filter coefficient may be the filter coefficient at other times.

[0207] The updated filter coefficients may be parameters of the next time adaptive filter.

[0208] In some embodiments, the preset filter coefficients may be updated according to the update value, and the updated filter coefficients may be obtained in a variety of ways. For example, a linear function may be established based on the update value and the preset filter coefficients, and the updated filter coefficients may be determined based on the linear function. Exemplarily, the preset filter coefficients may be updated according to the update value based on the formula w(n+1)=w(n)+Δw(n) to obtain the updated filter coefficients.

[0209] In some embodiments, the filter coefficient at the current moment may be updated according to the update value obtained at each moment to obtain the updated filter coefficient at the next moment.

[0210] In some embodiments, the filter coefficient at the current moment can be updated according to the updated value obtained at each moment, and the updated filter coefficient at the next moment can be obtained in a variety of ways. For example, the updated filter coefficient at the next moment can be determined based on the updated value and the filter coefficient at the current moment by the formula w(n+1)=w(n)+Δw(n).

[0211] In some embodiments, each moment includes each time point experienced by the adaptive filter when processing the reference signal and the error signal. At the above time point, the adaptive filter calculates the filter coefficient of the next moment based on the input reference signal and the error signal at the current moment and the filter coefficient of the current moment.

[0212] The next moment refers to a time point after the current moment. In an adaptive filter, the update value at the current moment is used to update the filter coefficient at the current moment, and the updated filter coefficient is used to output a control signal at the next moment.

[0213] In some embodiments of the present specification, by updating the filter coefficients, the adaptive filter can continuously optimize its performance so that the output control signal and the reference signal can achieve the effect of interference cancellation as much as possible.

[0214] In some embodiments of the present specification, the filter coefficient is determined by the second noise signal and the reference signal, so that the adaptive filter can specifically reduce the noise at the target position and improve the noise reduction effect at the target position; continuously updating the filter coefficient can make the system dynamically adapt to the changing noise environment and improve the real-time performance of noise control.

[0215] It should be noted that, since it is necessary to output the noise reduction signal corresponding to the operating parameters of the air-conditioning device in real time, the filter coefficients of the adaptive filter are updated in an uninterrupted iterative manner. Therefore, the noise control module needs to monitor the working condition of the air-conditioning device in real time. When it detects that the working condition of the air-conditioning device has changed (for example, the operating parameters have changed), the noise control module can adjust the filter coefficients of the adaptive filter. Set to 0, and call the noise signal corresponding to the operating parameters in the preset database, and restart the updating of the filter coefficients of the adaptive filter under the noise signal Achieve dynamic noise reduction.

[0216] It should be noted that the above description of the relevant process is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the process under the guidance of this specification. However, these modifications and changes are still within the scope of this specification.

[0217] Figure 4 is an exemplary schematic diagram of the virtual microphone technology shown in some embodiments of the present specification.

[0218] like Figure 4 As shown in the figure, the primary path and the secondary path are the acoustic path from the noise source to the first sensor (such as a physical microphone) and the acoustic path from the vehicle speaker to the first sensor, respectively. Both are actual physical paths. The error signal e at the first sensor is p (n) is the signal actually received at the first sensor.

[0219] In some embodiments, the virtual microphone technology is divided into a training phase and a control phase. In the training phase, the second sensor (e.g., virtual microphone) needs to be installed at the target location (i.e., the desired noise reduction location) and the first sensor needs to be installed at a relatively hidden location. At the same time, the adaptive filtering method can be used to calculate: 1) the secondary path estimate between the vehicle speaker and the first sensor; (Also called the first transfer function); 2) Estimation of the secondary path from the vehicle speaker to the second sensor (installed during secondary path identification and cancelled after completion) (Also called the third transfer function); 3) Secondary path estimation from the first sensor to the second sensor (It can also be called the second transfer function).

[0220] Before the control phase begins, the second sensor needs to be removed, and the second error signal at the target position is estimated based on the error signal at the first sensor, so as to achieve the effect of separating the noise reduction area and the error microphone.

[0221] In some embodiments, the first expected noise signal is an estimate of the expected signal at the first sensor. The first expected noise signal can be determined based on formula (1):

[0222]

[0223] in, is the first expected noise signal, y(n) is the preset control signal, is the first transfer function between the position of the vehicle speaker and the position of the first sensor (i.e., the acquisition position), is the result of the convolution of the preset control signal and the first transfer function, e p (n) is the first error signal at the first sensor, and * represents convolution.

[0224] In some embodiments, the second expected noise signal is an estimate of the expected signal at the second sensor, and the second expected noise signal can be obtained by estimating the expected signal at the first sensor. For example, the second expected noise signal can be determined based on formula (2):

[0225]

[0226] in, is the second expected noise signal at the second sensor, is a second transfer function between the position of the first sensor (ie, the acquisition position) and the position of the second sensor (ie, the target position).

[0227] In some embodiments, an estimate of the error signal at the second sensor may be determined based on equation (3):

[0228]

[0229] in, is the second error signal at the second sensor, is the third transfer function between the position of the vehicle speaker and the position of the second sensor (i.e., the target position), It is the result of the convolution of the preset control signal and the third transfer function.

[0230] In some embodiments, the preset control signal may be obtained by convolution of the reference signal at the current moment and the filter coefficient of the adaptive filter at the current moment. For example, the preset control signal may be determined based on formula (4).

[0231]

[0232] Among them, x(n) is the reference signal at the current moment, is the filter coefficient at the current moment.

[0233] In some embodiments, the filter coefficient of the adaptive filter can be determined by the following formula (5):

[0234]

[0235] in, is the updated filter coefficient, μ is the convergence step size, x'(n) is the filtered reference signal, and the filtered reference signal can be obtained based on the convolution of the reference signal and the third transfer function. For example, the filtered reference signal can be determined based on formula (6).

[0236]

[0237] In some embodiments, a sample reference signal can be determined based on a sample noise signal played by a playback device; a sample error signal can be determined based on a signal collected by a sensor at a preset position; a sample filter coefficient can be determined based on the sample reference signal and the sample error signal; and a sample transfer function can be determined based on the sample filter coefficient.

[0238] The sample noise signal refers to a preset noise signal. For example, the sample noise signal may be white noise or a random noise sequence.

[0239] The preset positions are positions associated with each secondary path estimate during the training phase.

[0240] The sample reference signal is a signal related to noise in the training phase. For example, the sample reference signal may be a sample noise signal, or a signal determined based on the sample noise signal.

[0241] The sample error signal refers to the error signal collected during the training phase.

[0242] The sample filter coefficients are a set of parameters that define the sound transmission characteristics of each secondary path.

[0243] The sample transfer function is a mathematical model of each secondary path.

[0244] In some embodiments, the preset position may include a collection position and / or a target position, and correspondingly, the sample transfer function is one of a first transfer function, a second transfer function, and a third transfer function.

[0245] In some embodiments, if the preset position is the acquisition position, the sample transfer function is the first transfer function. Exemplarily, the sample noise signal played by the playback device can be used as a sample reference signal; based on the signal collected by the first sensor at the acquisition position, a sample error signal is determined; based on the sample reference signal and the sample error signal, a sample filter coefficient is determined by an adaptive filtering algorithm; based on the sample filter coefficient, the first transfer function is determined.

[0246] In some embodiments, if the preset position is the target position, the sample transfer function is the third transfer function. Exemplarily, the sample noise signal played by the playback device can be used as a sample reference signal; based on the signal collected by the second sensor at the target position, a sample error signal is determined; based on the sample reference signal and the sample error signal, a sample filter coefficient is determined by an adaptive filtering algorithm; based on the sample filter coefficient, the third transfer function is determined.

[0247] In some embodiments, if the preset position includes a collection position and a target position, the sample transfer function is a second transfer function. Exemplarily, based on the sample noise signal played by the playback device, the signal collected by the first sensor at the collection position is used as a sample reference signal; based on the signal collected by the second sensor at the target position, a sample error signal is determined; based on the sample reference signal and the sample error signal, a sample filter coefficient is determined by an adaptive filtering algorithm; based on the sample filter coefficient, a second transfer function is determined. Wherein, the playback device is located close to the collection position.

[0248] In some embodiments, an adaptive filtering algorithm may be used during the training phase to obtain a secondary path estimate (i.e., a first transfer function) between the vehicle speaker and the first sensor. Secondary path estimation (i.e., third transfer function) from the vehicle speaker to the second sensor (installed during the secondary path identification and removed after completion) Secondary path estimation from the first sensor to the second sensor (i.e., the second transfer function)

[0249] For example, when the vehicle is stationary and without other noise interference, the first transfer function can be estimated: a white noise signal is generated by computing software as a reference signal of the system, the white noise signal is played by a playback device, an error signal is determined based on the signal played by the playback device collected by the first sensor, and the first transfer function is calculated by adaptively updating the coefficients of the adaptive filter using the least mean square algorithm (LMS). The LMS algorithm is an algorithm that uses a gradient descent algorithm to iterate the coefficients of the adaptive filter, and the output signal calculated by using the filter can offset the source noise to minimize the mean square of the error signal.

[0250] For another example, when the vehicle is stationary and without other noise interference, the third transfer function can be estimated: a white noise signal is generated by computing software as a reference signal of the system, the white noise signal is played by a playback device, and an error signal is determined based on the signal played by the playback device acquired by the second sensor. The error signal is adaptively updated using the least mean square algorithm (LMS) to calculate the third transfer function.

[0251] For another example, when the vehicle is stationary and without other noise interference, the second transfer function can be estimated: a white noise signal is generated using computing software and played by a playback device near a preset sensor position, the signal played by the playback device acquired by the preset sensor is used as a reference signal, and based on the signal acquired by the second sensor, an error signal is determined, and an adaptive update is performed using a least mean square algorithm (LMS) to calculate the second transfer function.

[0252] In some embodiments of the present specification, before the active noise reduction system is started or operated, the models of each secondary path are determined based on experiments, which helps to accurately estimate the error signal of the target position and improve the noise reduction effect of the target position.

[0253] Figure 5 It is an exemplary schematic diagram of the active noise reduction effect shown in some embodiments of this specification.

[0254] like Figure 5 As shown, the horizontal axis represents time, and the vertical axis represents sound intensity (such as sound pressure level). The lower the sound intensity at a certain location, the smaller the sound pressure level at that location, and the weaker the sound intensity. Sound pressure level is a physical quantity that describes the intensity of sound. It is determined by comparing the ratio of the sound pressure of the sound to a reference sound pressure. Based on the method or process described in the embodiment of the present application, the sound intensity at the location of the second sensor can be significantly reduced, and the noise reduction effect is significant.

[0255] Figure 7 is a schematic diagram of the structure of an electronic device according to some embodiments of this specification. Figure 7 As shown, the electronic device is arranged in a vehicle, such as Figure 7 As shown, Figure 7 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device 700 includes a processor 701 having one or more processing cores, a memory 702 having one or more computer-readable storage media, and a computer program stored in the memory 702 and executable on the processor. The processor 701 is electrically connected to the memory 702. It will be understood by those skilled in the art that the vehicle structure shown in the figure does not constitute a limitation on the vehicle, and may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0256] The processor 701 is the control center of the electronic device 700, and uses various interfaces and lines to connect various parts of the entire electronic device 700. By running or loading software programs and / or units stored in the memory 702, and calling data stored in the memory 702, the processor 701 executes various functions of the electronic device 700 and processes data, thereby monitoring the electronic device 700 as a whole. The processor 701 can be a processor CPU (Central Processing Unit), a graphics processor GPU (Graphics Processing Unit), a network processor (Network Processor, NP), etc., and can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiments of the present application.

[0257] In an embodiment of the present application, the processor 701 in the electronic device 700 will load the computer program corresponding to the process of one or more applications into the memory 702 according to the method or steps described in the above embodiment, and the processor 701 will run the application stored in the memory 702 to perform the active noise reduction method.

[0258] The specific implementation of the above operations can be found in the previous embodiments, which will not be described in detail here.

[0259] Optional, such as Figure 7 As shown, the electronic device 700 further includes: a touch screen 703, a radio frequency circuit 704, an audio circuit 705, an input unit 706, and a power supply 707. The processor 701 is electrically connected to the touch screen 703, the radio frequency circuit 704, the audio circuit 705, the input unit 706, and the power supply 707, respectively. Those skilled in the art can understand that Figure 7 The vehicle structure shown in the figure does not constitute a limitation on the vehicle, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0260] The touch display screen 703 can be used to display a graphical user interface and receive operation instructions generated by the user acting on the graphical user interface. The touch display screen 703 may include a display panel and a touch panel. Among them, the display panel can be used to display information input by the user or information provided to the user and various graphical user interfaces of the vehicle, which can be composed of graphics, text, icons, videos and any combination thereof. Optionally, the display panel can be configured in the form of a liquid crystal display (LCD, Liquid Crystal Display), an organic light-emitting diode (OLED, Organic Light-Emitting Diode), etc. The touch panel can be used to collect the user's touch operation on or near it (such as the user uses any suitable object or accessory such as a finger, a stylus, etc. on the touch panel or near the touch panel), and generate corresponding operation instructions, and the operation instructions execute the corresponding program. Optionally, the touch panel may include two parts: a touch detection device and a touch controller. Among them, the touch detection device detects the user's touch orientation, detects the signal brought by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts it into the touch point coordinates, and then sends it to the processor 701, and can receive the command sent by the processor 701 and execute it. The touch panel can cover the display panel. When the touch panel detects a touch operation on or near it, it is transmitted to the processor 701 to determine the type of touch event, and then the processor 701 provides a corresponding visual output on the display panel according to the type of touch event. In an embodiment of the present application, the touch panel and the display panel can be integrated into the touch display screen 703 to realize the input and output functions. However, in some embodiments, the touch panel and the touch panel can be used as two independent components to realize the input and output functions. That is, the touch display screen 703 can also be used as a part of the input unit 706 to realize the input function.

[0261] The RF circuit 704 may be used to send and receive RF signals to establish wireless communication with network devices or other vehicles through wireless communication, and to send and receive signals with network devices or other vehicles.

[0262] The audio circuit 705 can be used to provide an audio interface between the user and the vehicle through a speaker and a microphone. The audio circuit 705 can transmit the electrical signal converted from the received audio data to the speaker, which is converted into a sound signal for output; on the other hand, the microphone converts the collected sound signal into an electrical signal, which is received by the audio circuit 705 and converted into audio data, and then the audio data is output to the processor 701 for processing, and then sent to another vehicle through the radio frequency circuit 704, or the audio data is output to the memory 702 for further processing. The audio circuit 705 may also include an earplug jack to provide communication between an external headset and the vehicle.

[0263] The input unit 706 may be used to receive input numbers, character information or user feature information (such as fingerprint, iris, facial information, etc.), and generate keyboard, mouse, joystick, optical or trackball signal input related to user settings and function control.

[0264] The power supply 707 is used to supply power to various components of the electronic device 700. Optionally, the power supply 707 can be logically connected to the processor 701 through a power management device, so as to manage charging, discharging, and power consumption through the power management device. The power supply 707 can also include one or more DC or AC power supplies, recharging devices, power failure detection circuits, power converters or inverters, power status indicators, and other arbitrary components.

[0265] although Figure 7 Not shown, the electronic device 700 may also include a camera, a sensor, a wireless fidelity module, a Bluetooth module, etc., which will not be described in detail here.

[0266] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0267] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided, and when the program instructions are executed by the processor, the steps of the above-mentioned active noise reduction method are implemented. For example, the computer-readable storage medium can be the above-mentioned memory 702 including program instructions, and the above-mentioned program instructions can be executed by the processor 701 of the electronic device 700 to implement or execute the various methods, steps and logic block diagrams disclosed in the embodiments of the present application.

[0268] Or, when the instructions are executed by a computer, they are executed to implement or execute the methods, steps and logic block diagrams disclosed in the embodiments of the present application.

[0269] The present application also provides a vehicle, on which the active noise reduction system provided by any of the above embodiments is provided, and the active noise reduction system is used to execute the active noise reduction method provided by any of the above embodiments.

[0270] In one embodiment, the vehicle may be configured to be in a fully or partially automated driving mode. For example, the vehicle may control itself while in automated driving mode, and may determine the current state of the vehicle and its surroundings through human operation, determine the possible behavior of at least one other vehicle in the surroundings, and determine the confidence level corresponding to the possibility of the other vehicle performing the possible behavior, and control the vehicle based on the determined information. When the vehicle is in automated driving mode, the vehicle may be set to operate without human interaction.

[0271] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0272] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0273] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. Although the descriptions of various embodiments in the embodiments of the present application have different focuses, for parts not described in detail in a certain embodiment, reference can be made to the relevant embodiments of other embodiments. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. An active noise reduction method, characterized in that: The method is applied to a vehicle, and comprises: Acquiring operating parameters of the air conditioning device on the vehicle and a first error signal collected by a preset sensor; Reading a noise signal corresponding to the operating parameters of the air conditioner from a preset database as a reference signal; determining a filter coefficient based on the reference signal and the first error signal; The reference signal is processed based on the filter coefficient to obtain a control signal and play it to reduce noise on the reference signal.

2. The method according to claim 1, characterized in that The operating parameters include at least one of wind speed level, air outlet position, wind direction, and operating mode.

3. The method according to claim 1, characterized in that: The determining of a filter coefficient based on the reference signal and the first error signal comprises: Based on the acquisition position and the target position of the first error signal, the first error signal is processed to obtain a second error signal of the target position; The filter coefficient is determined based on the second error signal and the reference signal.

4. The method according to claim 3, characterized in that The step of processing the first error signal based on the acquisition position and the target position of the first error signal to obtain a second error signal of the target position includes: Determining a first expected noise signal at the acquisition position based on the first error signal and a preset control signal; Determining a second expected noise signal at the target location based on the first expected noise signal; The second error signal is determined based on the second expected noise signal and the preset control signal.

5. The method according to claim 4, characterized in that The determining, based on the first error signal and a preset control signal, a first expected noise signal at the acquisition position comprises: filtering the preset control signal based on a first transfer function to obtain a first preset control signal, wherein the first transfer function is an acoustic transfer function from the playback device to the collection position; The first expected noise signal is obtained based on the difference between the first error signal and the first preset control signal.

6. The method according to claim 4, characterized in that The step of determining a second expected noise signal at the target location based on the first expected noise signal comprises: The first expected noise signal is filtered based on a second transfer function to obtain a second expected noise signal at the target position, wherein the second transfer function is an acoustic transfer function from the acquisition position to the target position.

7. The method according to claim 4, characterized in that The determining the second error signal based on the second expected noise signal and the preset control signal comprises: filtering the preset control signal based on a third transfer function to obtain a second preset control signal, wherein the third transfer function is an acoustic transfer function between the playback device and the target position; The second error signal is obtained based on the sum of the second expected noise signal and the second preset control signal.

8. The method according to claim 4, characterized in that The method further comprises: The reference signal at the current moment is processed according to the filter coefficient obtained at each moment to obtain the control signal at the current moment as the preset control signal.

9. The method according to claim 3, characterized in that: The determining the filter coefficient based on the second error signal and the reference signal comprises: Determining an update value based on the reference signal, the second error signal and a preset step size; The preset filter coefficient is updated based on the update value to obtain the updated filter coefficient.

10. The method according to claim 9, characterized in that The step of determining an update value based on the reference signal, the second error signal and a preset step size comprises: Filtering the reference signal based on a third transfer function to obtain a filtered reference signal; The update value is determined based on the filtered reference signal, the second error signal and a preset step size.

11. The method according to claim 10, characterized in that The determining the update value based on the filtered reference signal, the second error signal and a preset step size comprises: Obtaining an update step size based on a ratio of the preset step size to the power of the reference signal; The update value is obtained based on the product of the filtered reference signal, the second error signal and the update step size.

12. The method according to claim 9, characterized in that The updating of the preset filter coefficient based on the update value to obtain the updated filter coefficient includes: The filter coefficient at the current moment is updated according to the update value obtained at each moment to obtain the updated filter coefficient at the next moment.

13. The method according to claim 4, characterized in that The method further comprises: Based on the sample noise signal, determining a sample reference signal; Determine a sample error signal based on a signal collected by a sensor at a preset position; determining sample filter coefficients based on the sample reference signal and the sample error signal; Based on the sample filter coefficients, a sample transfer function is determined.

14. The method according to claim 13, characterized in that The preset position includes the acquisition position and / or the target position, and correspondingly, the sample transfer function is one of a first transfer function, a second transfer function and a third transfer function.

15. An active noise reduction system, characterized in that: The system comprises: A sound collection module, wherein the sound collection module includes a preset sensor for collecting a first error signal; Noise control modules for: Acquiring operating parameters of the air conditioning device on the vehicle and a first error signal collected by a preset sensor; Reading a noise signal corresponding to the operating parameters of the air conditioner from a preset database as a reference signal; determining a filter coefficient based on the reference signal and the first error signal; Processing the reference signal based on the filter coefficient to obtain a control signal and play the control signal to reduce noise on the reference signal; The playing device is used for receiving and playing the control signal.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer storage medium stores instructions, which, when executed by a computer, enable the computer to implement the active noise reduction method according to any one of claims 1 to 14.

17. An electronic device, characterized in that: include: a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the active noise reduction method according to any one of claims 1 to 14.

18. A vehicle, characterized in that: Includes the active noise reduction system according to claim 15 or the electronic device according to claim 17.

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