Sound field balancing method and device for in-vehicle sound waves, electronic equipment, medium and product

Abstract

The invention relates to a sound field balancing method and device for sound waves in a vehicle, electronic equipment, a medium and a product. Comprising the steps that preset time domain noise is played through a plurality of loudspeakers of a vehicle with a sound field to be balanced, sound pressure signals are collected through first to fourth collection pieces, and corresponding to fourth frequency response amplitudes at a plurality of preset center frequencies are extracted; calculating a difference value between the maximum frequency response amplitude and the minimum frequency response amplitude at each center frequency, and identifying a target center frequency of which the difference value is greater than a preset threshold value; and determining target parameters of each loudspeaker IIR filter according to the frequency response amplitude at the target center frequency, adjusting the corresponding parameters based on the preset sampling frequency, and iteratively calculating the standard deviation of the frequency response amplitude until the difference values at all the target center frequencies are smaller than or equal to a preset threshold value. Therefore, the problems that sound fields of four positions including the front row and the rear row in the vehicle are not uniform, and particularly when the acoustic performance of the whole vehicle is poor, sound wave balance is difficult to achieve are solved, and the driving experience of a user is greatly improved.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a method, apparatus, electronic device, medium and product for equalizing the sound field of in-vehicle sound waves. Background Technology

[0002] Due to the transformation of the energy architecture, electric vehicles are generally quieter to drive and lack the power of driving a gasoline car. Therefore, many users will use the in-car speakers to emit sound waves that change with the car's speed, RPM, torque and other parameters to experience the power of a gasoline car. However, the uneven sound field in the four positions (front and rear) of the car, especially when the overall acoustic performance of the vehicle is poor, makes it difficult to achieve sound balance, which greatly affects the user's driving experience and urgently needs to be solved. Summary of the Invention

[0003] This application provides a sound field equalization method for in-vehicle sound waves to solve the problem of uneven sound field in the four positions of the front and rear seats, especially when the overall acoustic performance of the vehicle is poor, which makes it difficult to achieve sound wave balance, and greatly improves the user's driving experience.

[0004] To achieve the above objectives, the first aspect of this application proposes a sound field equalization method for in-vehicle sound waves, wherein first to fourth acquisition devices are respectively installed at the first to fourth positions of the vehicle to be equalized, and the method includes the following steps: When a preset time-domain noise is played through multiple speakers of the vehicle to be equalized in the sound field, the first to fourth frequency response amplitudes at multiple preset center frequencies are extracted based on the sound pressure signals collected by the first to fourth acquisition devices. Based on the first to fourth frequency response amplitudes at each preset center frequency, calculate the difference between the maximum and minimum frequency response amplitudes at each preset center frequency, and identify at least one target center frequency where the difference is greater than a preset threshold. Based on the first to fourth frequency response amplitudes at each target center frequency, the target parameters of the IIR filter for each loudspeaker are determined. Based on a preset sampling frequency, the IIR filter parameters of the corresponding loudspeaker are adjusted according to the target parameters of the IIR filter for each loudspeaker. The standard deviation of the frequency response amplitude at the target center frequency is iteratively calculated until the difference between the maximum and minimum frequency response amplitudes at all target center frequencies is less than or equal to the preset threshold.

[0005] According to one embodiment of this application, determining the target parameters of the IIR filter for each loudspeaker based on the first to fourth frequency response amplitudes at each target center frequency includes: Calculate the standard deviation of the frequency response amplitude at each target center frequency based on the first to fourth frequency response amplitudes at each target center frequency; Based on the standard deviation of the frequency response amplitude at each target center frequency and the difference between the maximum and minimum frequency response amplitudes at each preset center frequency, the target parameters of the IIR filter for each loudspeaker are determined.

[0006] According to one embodiment of this application, the standard deviation of the frequency response amplitude is: ; in, The standard deviation of the frequency response amplitude. For the number of frequency points, The average amplitude of the frequency response, This is the frequency response function.

[0007] According to one embodiment of this application, the frequency response amplitude is: ; in, Indicates at angular frequency The amplitude of the frequency response at that point, Indicates the total number of frequency points. Indicates the position of the i-th microphone. Indicates the location At, for frequency The output of the signal, It is the frequency domain representation of the input signal.

[0008] According to one embodiment of this application, before playing a preset time-domain noise through multiple speakers of the vehicle whose sound field is to be equalized, the method further includes: Obtain powertrain data for the target vehicle; Based on a preset sound synthesis algorithm, the preset time-domain noise is generated according to the powertrain data.

[0009] The in-vehicle sound field equalization method proposed in this application collects frequency response amplitudes at multiple locations, identifies target frequencies exceeding a threshold, adjusts the IIR filter parameters of each speaker, and iteratively optimizes the process until the difference in frequency response amplitudes at multiple locations at each target frequency meets the threshold requirement, thereby achieving in-vehicle sound field equalization. This solves the problem of uneven sound field distribution across the four locations (front and rear seats), particularly when the overall vehicle acoustic performance is poor, making it difficult to achieve sound field balance and significantly improving the user's driving experience.

[0010] To achieve the above objectives, a second aspect of this application provides a sound field equalization device for in-vehicle sound waves. First to fourth acquisition elements are correspondingly installed at the first to fourth positions of the vehicle to be equalized. The device includes: The acquisition module is used to extract the first to fourth frequency response amplitudes at multiple preset center frequencies based on the sound pressure signals acquired by the first to fourth acquisition devices when a preset time-domain noise is played through multiple speakers of the vehicle to be equalized in the sound field. The calculation module calculates the difference between the maximum and minimum frequency response amplitudes at each preset center frequency based on the first to fourth frequency response amplitudes at each preset center frequency, and identifies at least one target center frequency where the difference is greater than a preset threshold. The equalization module determines the target parameters of the IIR filter for each speaker based on the first to fourth frequency response amplitudes at each target center frequency. Based on a preset sampling frequency, it adjusts the IIR filter parameters of the corresponding speaker according to the target parameters of the IIR filter for each speaker, and iteratively calculates the standard deviation of the frequency response amplitude at the target center frequency until the difference between the maximum and minimum frequency response amplitudes at all target center frequencies is less than or equal to the preset threshold.

[0011] According to one embodiment of this application, the equalization module is further configured to: Calculate the standard deviation of the frequency response amplitude at each target center frequency based on the first to fourth frequency response amplitudes at each target center frequency; Based on the standard deviation of the frequency response amplitude at each target center frequency and the difference between the maximum and minimum frequency response amplitudes at each preset center frequency, the target parameters of the IIR filter for each loudspeaker are determined.

[0012] According to one embodiment of this application, the standard deviation of the frequency response amplitude is: ; in, The standard deviation of the frequency response amplitude. For the number of frequency points, The average amplitude of the frequency response, This is the frequency response function.

[0013] According to one embodiment of this application, the frequency response amplitude is: ; in, Indicates at angular frequency The amplitude of the frequency response at that point, Indicates the total number of frequency points. Indicates the position of the i-th microphone. Indicates the location At, for frequency The output of the signal, It is the frequency domain representation of the input signal.

[0014] According to one embodiment of this application, before playing preset time-domain noise through multiple speakers of the vehicle to be sound-equalized, the acquisition module is further configured to: acquire powertrain data of the target vehicle; Based on a preset sound synthesis algorithm, the preset time-domain noise is generated according to the powertrain data.

[0015] The in-vehicle sound field equalization device proposed in this application collects frequency response amplitudes at multiple locations, identifies target frequencies exceeding a threshold, adjusts the IIR filter parameters of each speaker, and iteratively optimizes them until the difference in frequency response amplitudes at multiple locations at each target frequency meets the threshold requirement, thereby achieving in-vehicle sound field equalization. This solves the problem of uneven sound fields in the four locations (front and rear seats), particularly when the overall vehicle acoustic performance is poor, making it difficult to achieve sound field balance and significantly improving the user's driving experience.

[0016] To achieve the above objectives, a third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the in-vehicle sound field equalization method as described in the above embodiments.

[0017] To achieve the above objectives, a fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the in-vehicle sound field equalization method as described in the above embodiments.

[0018] To achieve the above objectives, a fifth aspect of this application provides a computer program product, including a computer program executed by a processor, for implementing the in-vehicle sound field equalization method as described in the above embodiments.

[0019] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0020] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart of a sound field equalization method for in-vehicle sound waves according to an embodiment of this application; Figure 2 This is a schematic diagram showing the arrangement of the loudspeaker and microphone according to one embodiment of this application; Figure 3 This is a schematic diagram of the microphone arrangement according to an embodiment of this application; Figure 4This is a schematic diagram of the spectrum at four locations inside the vehicle before commissioning, according to an embodiment of this application; Figure 5 This is a schematic diagram of the sound pressure levels at four locations inside the vehicle before commissioning, according to one embodiment of this application; Figure 6 This is a schematic diagram illustrating the effect of four door speakers on the sound pressure levels at four locations inside the vehicle according to an embodiment of this application; Figure 7 This is a schematic diagram of an IIR filter setting interface according to an embodiment of this application; Figure 8 This is a schematic diagram of the spectrum of a filter with a gain of 4.5 dB and a quality factor of 2 according to an embodiment of this application. Figure 9 This is a schematic diagram of the spectrum at four locations inside the vehicle after debugging, according to one embodiment of this application; Figure 10 This is a schematic diagram of the sound pressure level at four locations after debugging, according to an embodiment of this application; Figure 11 This is a schematic diagram comparing the standard deviation of the frequency response amplitude at each frequency point of four measurement points before and after equalization, according to an embodiment of this application. Figure 12 This is a schematic diagram comparing the standard deviation of the full-frequency response amplitude at four measurement points before and after equalization, according to an embodiment of this application. Figure 13 This is a schematic diagram illustrating the working principle of simulated sound waves according to an embodiment of this application; Figure 14 This is a flowchart of a sound wave synthesis algorithm according to an embodiment of this application; Figure 15 This is a flowchart of a sound field equalization method for in-vehicle sound waves according to an embodiment of this application; Figure 16 This is a block diagram of a sound field equalization device for in-vehicle sound waves provided according to an embodiment of this application; Figure 17 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of this application. Detailed Implementation

[0021] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0022] The following description, with reference to the accompanying drawings, describes a sound field equalization method for in-vehicle sound waves according to embodiments of this application. Addressing the aforementioned background art issue of uneven sound fields in the four locations (front and rear seats) of a vehicle, particularly the difficulty in achieving sound wave balance when the overall vehicle acoustic performance is poor, this application proposes a sound field equalization method for in-vehicle sound waves. This method involves collecting frequency response amplitudes at multiple locations, identifying target frequencies exceeding a threshold, adjusting the IIR filter parameters of each speaker, and iteratively optimizing until the difference in frequency response amplitudes at each target frequency meets the threshold requirement, thus achieving sound field equalization within the vehicle. This solves the problem of uneven sound fields in the four locations (front and rear seats), particularly the difficulty in achieving sound wave balance when the overall vehicle acoustic performance is poor, significantly improving the user's driving experience.

[0023] First, a sound field equalization method for in-vehicle sound waves according to an embodiment of this application will be described with reference to the accompanying drawings.

[0024] Figure 1 This is a flowchart of a sound field equalization method for in-vehicle sound waves according to an embodiment of this application.

[0025] like Figure 1 As shown, the sound field equalization method for the in-vehicle sound includes the following steps: In step S101, when preset time-domain noise is played through multiple speakers of the vehicle to be sound-field equalized, the first to fourth frequency response amplitudes at multiple preset center frequencies are extracted based on the sound pressure signals collected by the first to fourth acquisition devices.

[0026] Among them, time-domain noise refers to the noise signal presented in the time dimension; acquisition device refers to acoustic sensors such as microphones; sound pressure signal is the pressure fluctuation signal generated when sound propagates in the air; preset center frequency can be the center frequency set by the user in advance, the center frequency obtained through a limited number of experiments, or the center frequency obtained through a limited number of computer simulations, without specific limitations here; frequency response amplitude refers to the sound pressure level formed at a certain location after the sound has passed through the loudspeaker and the in-vehicle environment at a specific frequency.

[0027] Specifically, differences in sound pressure levels occur at four locations within the vehicle around frequencies of 150Hz, 1050Hz, 1950Hz, 2700Hz, and 3850Hz. Therefore, in this embodiment, 150Hz, 1050Hz, 1950Hz, 2700Hz, and 3850Hz are used as preset center frequencies. The vehicle to be equilibrated is placed in a semi-anechoic chamber to isolate external noise interference and ensure the accuracy of the collected data. Four speakers for playing sound waves are installed below the vehicle doors, arranged as follows: Figure 2As shown in the diagram, A, B, C, and D represent four speakers used to play sound, and 201, 202, 203, and 204 represent four microphones located above the seats in four key seating positions: the driver's seat, the front passenger seat, the left rear seat (behind the driver's seat), and the right rear seat (behind the front passenger seat). These are the test points, and their specific locations are shown in the diagram. Figure 3 As shown, by controlling the four speakers A, B, C, and D below the car door to synchronously play preset time-domain noise, and at the same time, the four microphones collect the sound pressure signals at their respective positions in real time, laying the data foundation for extracting the first to fourth frequency response amplitudes at multiple preset center frequencies from the sound pressure signals. The frequency response amplitude can be calculated using the following formula in this embodiment.

[0028] Optionally, in some embodiments, the frequency response amplitude is: ; in, Indicates at angular frequency The amplitude of the frequency response at that point, Indicates the total number of frequency points. Indicates the position of the i-th microphone. Indicates the location At, for frequency The output of the signal, It is the frequency domain representation of the input signal.

[0029] In step S102, based on the first to fourth frequency response amplitudes at each preset center frequency, the difference between the maximum and minimum frequency response amplitudes at each preset center frequency is calculated, and at least one target center frequency with a difference greater than a preset threshold is identified.

[0030] The preset threshold can be a threshold set by the user, a threshold obtained through a limited number of experiments, or a threshold obtained through a limited number of computer simulations; no specific limitation is made here.

[0031] Specifically, based on the white noise collected by four microphones in step S101, the sound field equalization at four locations inside the vehicle is detected. The microphone test results at the four locations are as follows: Figure 4 As shown, red indicates the microphone on the driver's side, orange indicates the microphone on the passenger side, yellow indicates the microphone on the left rear seat (behind the driver's side), and green indicates the microphone on the right rear seat (behind the passenger side).

[0032] Specifically, at a frequency around 600Hz, significant energy attenuation was observed at all four locations inside the vehicle, with an overall decreasing trend. This attenuation of sound energy reflects poor overall vehicle acoustic performance. The sound pressure levels measured at the microphones at the four locations are as follows: Figure 5As shown, the difference between the maximum and minimum values ​​is approximately 8 dB(A). This difference is compared to a preset threshold. Frequency ranges exceeding the threshold are identified as target center frequencies, which are the frequencies that require subsequent adjustment to achieve sound field equalization. In other words, if the difference in the amplitude of the first to fourth frequency responses at the preset center frequency of 150Hz is greater than the preset threshold, then the preset center frequency of 150Hz is taken as the target center frequency. If the difference in the amplitude of the first to fourth frequency responses at the preset center frequency of 150Hz is not greater than the preset threshold, then the preset center frequency of 150Hz is already balanced.

[0033] In step S103, the target parameters of the IIR filter for each loudspeaker are determined based on the first to fourth frequency response amplitudes at each target center frequency. Based on the preset sampling frequency, the IIR filter parameters of the corresponding loudspeaker are adjusted according to the target parameters of the IIR filter for each loudspeaker. The standard deviation of the frequency response amplitude at the target center frequency is iteratively calculated until the difference between the maximum and minimum frequency response amplitudes at all target center frequencies is less than or equal to a preset threshold.

[0034] Furthermore, in some embodiments, determining the target parameters of the IIR filter for each loudspeaker based on the first to fourth frequency response amplitudes at each target center frequency includes: calculating the standard deviation of the frequency response amplitude at each target center frequency based on the first to fourth frequency response amplitudes at each target center frequency; and determining the target parameters of the IIR filter for each loudspeaker based on the standard deviation of the frequency response amplitude at each target center frequency and the difference between the maximum and minimum frequency response amplitudes at each preset center frequency.

[0035] Furthermore, in some embodiments, the standard deviation of the frequency response amplitude is: ; in, The standard deviation of the frequency response amplitude. For the number of frequency points, The average amplitude of the frequency response, This is the frequency response function.

[0036] Specifically, frequency response function The expression is: ; Average amplitude of frequency response The calculation formula is: ; in, It is by Obtained by performing a Laplace transform. The specific formula is as follows: ; Specifically, It is the signal emitted by each speaker. System response of sound waves along the propagation path The result of the convolution. Among them, Indicates the number of microphones. Indicates the number of speakers in the vehicle. Let n represent the transfer function from the nth loudspeaker to the qth measuring point, where , Indicates the first The location of the microphone.

[0037] Based on the quantitative analysis of the in-vehicle sound field characteristics using the aforementioned formulas for frequency response function, frequency response amplitude, and standard deviation, the impact of the four door speakers on the sound pressure levels at four locations within the vehicle can be further verified through experiments: A set of white noise was played through the speakers using a sound synthesis algorithm, and the test results are as follows... Figure 6 As shown, at a frequency of 150Hz, the sound pressure level on the left rear seat (behind the driver's seat) and the right rear seat (behind the passenger seat) needs to be reduced. Therefore, the sound pressure levels of speakers A and B need to be reduced. However, reducing A and B will decrease the sound pressure level of the microphones at the driver and passenger seats. Therefore, the sound pressure levels of speakers C and D need to be increased. Furthermore, according to... Figure 5 a and Figure 5 As can be seen from b in the diagram, speakers C and D have a greater impact on the driver's and passenger's seats.

[0038] Next, the sound pressure level is modified using an IIR (Infinite Impulse Response) filter (Butterworth filter). The mathematical formula for a second-order IIR digital filter is as follows: ; Transforming to the discrete domain, the calculation formula is as follows: ; In the formula, This is the filtered value for the current sampling point. This is the filtered value from the previous sampling point. analogy, This is the value before filtering at the current sampling point. , And so on, , , and , , These are the coefficients of the filter.

[0039] To address the sound field imbalance at four locations within the vehicle, white noise was first used to play sound waves. Then, an IIR filter was designed to adjust the frequency response curve. The specific IIR filter settings interface is shown below. Figure 7 As shown, the center frequency needs to be set. sampling frequency Gain and quality factor Q, where the filter spectrum with a gain of 4.5 dB(A) and a quality factor of Q of 2 is shown in the figure. Figure 8 As shown, this visually demonstrates the filter's processing effect on different frequencies. Meanwhile, the energy of white noise is consistent across all frequencies, and the curve is completely flat. The smaller the value, the more consistent the energy at each frequency point, and the flatter the frequency response curve. The larger the value, the greater the fluctuation in the frequency response curve, which provides a reference for adjusting filter parameters.

[0040] In the specific IIR filter design, the center frequencies are set sequentially to 150Hz, 1050Hz, 1950Hz, 2700Hz, and 3850Hz, and the sampling frequency is set to 32000Hz. The gain and quality factor Q need to be adjusted according to the actual test results. By setting filters with different center frequencies in this way, combined with appropriate gain and quality factor, the sound signals of different frequency bands in the vehicle can be processed, thereby gradually improving the sound field distribution in the four positions, making it more balanced, and enhancing the listening experience of the driver and passengers.

[0041] By analyzing the impact of the sound waves emitted by each speaker on the sound pressure level at each location inside the vehicle, and repeatedly writing the designed filter into the sound synthesis program for adjustment, the resulting spectrum diagrams at four measurement points inside the vehicle are shown below. Figure 9 As shown in the diagram, where red represents the driver's microphone, orange represents the passenger's microphone, yellow represents the microphone on the left rear seat (behind the driver's seat), and green represents the microphone on the right rear seat (behind the passenger's seat), the differences in the spectrum at the four locations (150Hz, 1950Hz, 2700Hz, and 3850Hz) decrease. The sound pressure levels at the four measurement points are as follows: Figure 10 As shown, the difference between the maximum and minimum values ​​is within 3 dB(A), indicating that the sound field at the four measurement points inside the vehicle is relatively balanced.

[0042] The calculation results based on the above formulas for frequency response function, frequency response amplitude, and standard deviation are as follows: Figure 11 and Figure 12 As shown, the speakers in the vehicle whose sound field is to be equalized have an effective frequency range of 50Hz-6000Hz; therefore, the comparison only focuses on the effective frequency range of the speakers. Figure 11To compare the standard deviation of the frequency response amplitude at each frequency point before and after equalization, the standard deviation of the frequency response amplitude at each of the four measurement points was 16.9% before equalization and 11.7% after equalization. Figure 12 To compare the standard deviation of the full-frequency response amplitude at the four measurement points before and after equalization, the standard deviation of the average frequency response amplitude across the entire frequency band at the four measurement points before equalization was 21.6%, while that after equalization was 16.6%. Regardless of the full frequency band or a single frequency point, the standard deviation after equalization... Below equilibrium The frequency response at the four measurement points is more consistent, and the sound field inside the car is more balanced.

[0043] Therefore, by playing white noise and other tests, the target frequency that caused the sound field imbalance was identified. Then, the target parameters of each speaker were calculated using formulas such as frequency response function and standard deviation. The parameters were iteratively adjusted with 32000Hz as the sampling frequency. Finally, the verification results showed that the sound pressure level difference between the four positions in the car was controlled within 3dB, the frequency response consistency was significantly improved, and the sound field was balanced.

[0044] To make the testing and adjustment of sound field equalization more closely resemble the acoustic environment of a vehicle during real driving and improve the final user experience, this application also provides a customized test signal generation method based on the actual noise characteristics of the vehicle.

[0045] Optionally, in some embodiments, before playing a preset time-domain noise through multiple speakers of the vehicle to be sound-equalized, the method further includes: acquiring powertrain data of the target vehicle; and generating a preset time-domain noise based on the powertrain data using a preset sound synthesis algorithm.

[0046] Among them, powertrain data refers to the sound signal data generated by the vehicle's core power components such as engine and transmission during operation; sound wave synthesis algorithm is a digital signal processing algorithm that can analyze and simulate specific sounds.

[0047] Specifically, in this embodiment, powertrain data can be obtained from a pre-established database. It should be noted that the pre-established database can be based on empirical values ​​and / or experimental verification results. The powertrain data is then input into a pre-set sound synthesis algorithm. For example... Figure 13 As shown, Figure 13 The diagram below illustrates the working principle of the simulated sound wave according to an embodiment of this application. The core of the algorithm is to input power system data and output simulated sound waves from the in-vehicle speakers. It can analyze the input data and generate an audio signal in the computer that is highly similar to the sound of a real engine.

[0048] Specifically, such as Figure 14 As shown, Figure 14The flowchart of the sound wave synthesis algorithm provided in the embodiments of this application shows that the sound wave synthesis algorithm includes the following steps: S1401, Powertrain Data Input.

[0049] S1402 calculates the gain of the fundamental frequency (base frequency) and volume amplitude of the simulated sound wave based on the input power system data.

[0050] S1403 refines the key acoustic features of simulated sound waves through amplitude, frequency, and phase models.

[0051] S1404 performs filtering on the sound signal generated by the model, removing unwanted frequency components or noise to make the sound purer and closer to the sound of a real engine.

[0052] S1405 processes audio signals frame by frame, calculates data changes between frames, and ensures a smooth transition of sound waves in the time dimension.

[0053] S1406 adjusts the overall volume of the sound waves to ensure that the output volume meets the requirements.

[0054] S1407 is designed to equalize the acoustic environment inside the vehicle.

[0055] S1408, audio output.

[0056] Therefore, by using the engine sound synthesized by the preset sound wave synthesis algorithm as the test signal, it is possible to more efficiently discover and solve sound field problems that are excited or masked by specific engine noise, thereby enabling more targeted optimization.

[0057] To enable those skilled in the art to further understand the discharge power determination method of the embodiments of this application, a detailed description is provided below in conjunction with specific embodiments.

[0058] like Figure 15 As shown, Figure 15 This is a flowchart of a sound field equalization method for in-vehicle sound waves according to an embodiment of this application.

[0059] like Figure 15 As shown, the sound field equalization method for the in-vehicle sound includes the following steps: S1501, Begin.

[0060] S1502, obtain the overall vehicle frequency response and determine the frequency domain to be adjusted.

[0061] S1503, using the iirpeak function in MATLAB software, obtains the transfer function coefficients.

[0062] S1504 analyzes and adjusts the equalization (EQ) parameters of the four speakers (A, B, C, and D, corresponding to different positions in the vehicle).

[0063] S1505, determine whether the frequency response difference meets the requirements. If it does, proceed to step S1506; otherwise, return to step S1502.

[0064] S1506, End.

[0065] The in-vehicle sound field equalization method proposed in this application collects frequency response amplitudes at multiple locations, identifies target frequencies exceeding a threshold, adjusts the IIR filter parameters of each speaker, and iteratively optimizes the process until the difference in frequency response amplitudes at multiple locations at each target frequency meets the threshold requirement, thereby achieving in-vehicle sound field equalization. This solves the problem of uneven sound field distribution across the four locations (front and rear seats), particularly when the overall vehicle acoustic performance is poor, making sound field balance difficult to achieve and significantly improving the user's driving experience.

[0066] Next, with reference to the accompanying drawings, a sound field equalization device for in-vehicle sound waves according to an embodiment of this application is described.

[0067] Figure 16 This is a block diagram of a sound field equalization device for in-vehicle sound waves according to an embodiment of this application.

[0068] like Figure 16 As shown, the sound field equalization device for the in-vehicle sound wave includes: a data acquisition module 100, a calculation module 200, and an equalization module 300.

[0069] The acquisition module 100 is used to extract the first to fourth frequency response amplitudes at multiple preset center frequencies based on the sound pressure signals acquired by the first to fourth acquisition devices when a preset time-domain noise is played through multiple speakers of the vehicle to be sound field equalized. The calculation module 200 calculates the difference between the maximum and minimum frequency response amplitudes at each preset center frequency based on the first to fourth frequency response amplitudes at each preset center frequency, and identifies at least one target center frequency where the difference is greater than a preset threshold. The equalization module 300 determines the target parameters of the IIR filter for each speaker based on the first to fourth frequency response amplitudes at each target center frequency. Based on the preset sampling frequency, it adjusts the IIR filter parameters of the corresponding speaker according to the target parameters of the IIR filter for each speaker, and iteratively calculates the standard deviation of the frequency response amplitude at the target center frequency until the difference between the maximum and minimum frequency response amplitudes at all target center frequencies is less than or equal to a preset threshold.

[0070] According to one embodiment of this application, the equalization module 300 is further configured to: calculate the standard deviation of the frequency response amplitude of each target center frequency based on the first to fourth frequency response amplitudes at each target center frequency; and determine the target parameters of the IIR filter for each loudspeaker based on the standard deviation of the frequency response amplitude of each target center frequency and the difference between the maximum and minimum frequency response amplitudes at each preset center frequency.

[0071] According to one embodiment of this application, the standard deviation of the frequency response amplitude is: ; in, The standard deviation of the frequency response amplitude. For the number of frequency points, The average amplitude of the frequency response, This is the frequency response function.

[0072] According to one embodiment of this application, the frequency response amplitude is: ; in, Indicates at angular frequency The amplitude of the frequency response at that point, Indicates the position of the i-th microphone. Indicates the location At, for frequency The output of the signal, It is the frequency domain representation of the input signal.

[0073] According to one embodiment of this application, before playing preset time-domain noise through multiple speakers of the vehicle to be sound-equalized, the acquisition module 100 is further configured to: acquire powertrain data of the target vehicle; and generate preset time-domain noise based on the powertrain data using a preset sound wave synthesis algorithm.

[0074] It should be noted that the explanation of the aforementioned embodiment of the sound field equalization method for in-vehicle sound waves also applies to the sound field equalization device for in-vehicle sound waves in this embodiment, and will not be repeated here.

[0075] The in-vehicle sound field equalization device proposed in this application collects frequency response amplitudes at multiple locations, identifies target frequencies exceeding a threshold, adjusts the IIR filter parameters of each speaker, and iteratively optimizes them until the difference in frequency response amplitudes at multiple locations at each target frequency meets the threshold requirement, thereby achieving in-vehicle sound field equalization. This solves the problem of uneven sound fields in the four locations (front and rear seats), particularly when the overall vehicle acoustic performance is poor, making it difficult to achieve sound field balance and significantly improving the user's driving experience.

[0076] Figure 17 This is a schematic diagram of an electronic device provided in an embodiment of the present invention. The electronic device may include: The memory 1701, the processor 1702, and the computer program stored on the memory 1701 and executable on the processor 1702.

[0077] When the processor 1702 executes the program, it implements the sound field equalization method for in-vehicle sound waves provided in the above embodiments.

[0078] Furthermore, electronic devices also include: Communication interface 1703 is used for communication between memory 1701 and processor 1702.

[0079] Memory 1701 is used to store computer programs that can run on processor 1702.

[0080] The memory 1701 may include high-speed RAM (Random Access Memory) memory, and may also include non-volatile memory, such as at least one disk storage.

[0081] If the memory 1701, processor 1702, and communication interface 1703 are implemented independently, then the communication interface 1703, memory 1701, and processor 1702 can be interconnected via a bus to complete communication between them. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 17 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0082] Optionally, in a specific implementation, if the memory 1701, processor 1702, and communication interface 1703 are integrated on a single chip, then the memory 1701, processor 1702, and communication interface 1703 can communicate with each other through an internal interface.

[0083] Processor 1702 may be a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement embodiments of the present invention.

[0084] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for equalizing in-vehicle sound waves.

[0085] This invention also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method for equalizing the sound field of in-vehicle noise.

[0086] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0087] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0088] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for equalizing the sound field of in-vehicle noise, characterized in that, The first to fourth acquisition devices are respectively set at the first to fourth positions of the vehicle to be equalized in the sound field. The method includes the following steps: When a preset time-domain noise is played through multiple speakers of the vehicle to be equalized in the sound field, the first to fourth frequency response amplitudes at multiple preset center frequencies are extracted based on the sound pressure signals collected by the first to fourth acquisition devices. Based on the first to fourth frequency response amplitudes at each preset center frequency, calculate the difference between the maximum and minimum frequency response amplitudes at each preset center frequency, and identify at least one target center frequency where the difference is greater than a preset threshold. Based on the first to fourth frequency response amplitudes at each target center frequency, the target parameters of the IIR filter for each loudspeaker are determined. Based on a preset sampling frequency, the IIR filter parameters of the corresponding loudspeaker are adjusted according to the target parameters of the IIR filter for each loudspeaker. The standard deviation of the frequency response amplitude at the target center frequency is iteratively calculated until the difference between the maximum and minimum frequency response amplitudes at all target center frequencies is less than or equal to the preset threshold.

2. The method according to claim 1, characterized in that, The determination of the target parameters of the IIR filter for each loudspeaker based on the first to fourth frequency response amplitudes at each target center frequency includes: Calculate the standard deviation of the frequency response amplitude at each target center frequency based on the first to fourth frequency response amplitudes at each target center frequency; Based on the standard deviation of the frequency response amplitude at each target center frequency and the difference between the maximum and minimum frequency response amplitudes at each preset center frequency, the target parameters of the IIR filter for each loudspeaker are determined.

3. The method according to claim 2, characterized in that, The standard deviation of the frequency response amplitude is: ； in, The standard deviation of the frequency response amplitude is... For the number of frequency points, The average amplitude of the frequency response, This is the frequency response function.

4. The method according to claim 1, characterized in that, The frequency response amplitude is: ； in, Indicates at angular frequency The amplitude of the frequency response at that point, Indicates the total number of frequency points. Indicates the position of the i-th microphone. Indicates the location At, for frequency The output of the signal, It is the frequency domain representation of the input signal.

5. The method according to claim 1, characterized in that, Before playing preset time-domain noise through multiple speakers of the vehicle to be sound-equalized, the method further includes: Obtain powertrain data for the target vehicle; Based on a preset sound synthesis algorithm, the preset time-domain noise is generated according to the powertrain data.

6. A sound field equalization device for in-vehicle sound waves, characterized in that, The first to fourth positions of the vehicle to be sound field equalized are each equipped with a first to fourth acquisition element, wherein the device includes: The acquisition module is used to extract the first to fourth frequency response amplitudes at multiple preset center frequencies based on the sound pressure signals acquired by the first to fourth acquisition devices when a preset time-domain noise is played through multiple speakers of the vehicle to be equalized in the sound field. The calculation module calculates the difference between the maximum and minimum frequency response amplitudes at each preset center frequency based on the first to fourth frequency response amplitudes at each preset center frequency, and identifies at least one target center frequency where the difference is greater than a preset threshold. The equalization module determines the target parameters of the IIR filter for each speaker based on the first to fourth frequency response amplitudes at each target center frequency. Based on a preset sampling frequency, it adjusts the IIR filter parameters of the corresponding speaker according to the target parameters of the IIR filter for each speaker, and iteratively calculates the standard deviation of the frequency response amplitude at the target center frequency until the difference between the maximum and minimum frequency response amplitudes at all target center frequencies is less than or equal to the preset threshold.

7. The apparatus according to claim 6, wherein the equalization module is further configured to: Calculate the standard deviation of the frequency response amplitude at each target center frequency based on the first to fourth frequency response amplitudes at each target center frequency; Based on the standard deviation of the frequency response amplitude at each target center frequency and the difference between the maximum and minimum frequency response amplitudes at each preset center frequency, the target parameters of the IIR filter for each loudspeaker are determined.

8. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the sound field equalization method for in-vehicle sound as described in any one of claims 1-5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the sound field equalization method for in-vehicle sound waves as described in any one of claims 1-5.

10. A computer program product, comprising a computer program, characterized in that, The computer program is executed by a processor to implement the sound field equalization method for in-vehicle sound waves as described in any one of claims 1-5.

Images