Audio power amplifier power adjustment system

Abstract

The application provides an audio power amplifier power adjusting system. The sound collection array of the audio power amplifier power adjusting system comprises a plurality of sound collection units arranged at different positions of a vehicle for collecting environmental noise information and voice input information. A master control module is electrically connected with the sound collection array and a power amplifier module, used for obtaining a basic power of the current vehicle, determining a noise adjusting power according to a noise mapping relationship database, determining a voice correcting power according to a voice input information and a power correction rule database, obtaining an actual adjusting power according to the noise adjusting power, the voice correcting power and the basic power, and sending the actual adjusting power to the power amplifier module. In this way, the noise mapping relationship database and the power correction rule database can realize step-by-step adjustment of different noise intensities, improve the accuracy of adjustment, and ensure clear playing sound while avoiding suppressing voice communication.

Description

Technical Field

[0001] This invention relates to the field of loudspeaker technology, and more particularly to an audio amplifier power adjustment system. Background Technology

[0002] With the rapid development of intelligent and electric vehicles, users have placed higher demands on the adaptability and experience of in-vehicle audio playback. The application of multi-channel in-vehicle amplifiers is becoming increasingly widespread, and their power configuration and scene adaptability have become core aspects of the user experience. The in-vehicle environment has significant dynamic characteristics, encountering complex and varied environmental noises during driving, such as wind and tire noise at high speeds, traffic congestion and pedestrian noise in urban areas, and low-noise environments in quiet scenarios like parking lots and rural roads. Simultaneously, the cockpit also contains voice signals from driver and passenger interactions and voice command inputs, all of which together constitute the complex acoustic environment of an in-vehicle vehicle.

[0003] Currently, existing automotive amplifier output technology mainly relies on manual multi-level adjustment schemes, with some improved schemes only achieving simple power adjustment based on a single parameter of ambient noise. The drawbacks of this type of solution are: the adjustment process depends on the user's subjective judgment and manual operation, and cannot respond in real time to dynamic changes in ambient noise. For example, when a vehicle moves from city roads to highways, the noise intensity increases significantly in a short period, requiring the user to manually switch power levels, which is cumbersome and has a response delay. Furthermore, some single-noise adjustment schemes only achieve power switching through fixed threshold comparisons, lacking a refined adaptation database, resulting in low power adjustment accuracy and an inability to match the acoustic requirements of different noise intensities. Summary of the Invention

[0004] This invention provides an audio amplifier power adjustment system that can achieve step-by-step adjustment of different noise intensities through a noise mapping relationship library and a power correction rule library, thereby improving the accuracy of adjustment and ensuring clear playback while avoiding suppression of human voice communication, thus enhancing the user experience.

[0005] In a first aspect, embodiments of the present invention provide an audio power amplifier power adjustment system, the audio power amplifier power adjustment system comprising a sound acquisition array, a main control module, and a power amplifier module;

[0006] The sound acquisition array includes multiple sound acquisition units, which are located at different positions in the vehicle and are used to collect environmental noise information and voice input information.

[0007] The main control module is electrically connected to the sound acquisition array and the power amplifier module respectively. It is used to obtain the current vehicle's base power, determine the noise adjustment power according to the environmental noise information and noise mapping relationship library, determine the human voice correction power according to the voice input information and power correction rule library, obtain the actual adjustment power according to the noise adjustment power, the human voice correction power and the base power, and send the actual adjustment power to the power amplifier module.

[0008] Optionally, obtaining the actual adjustment power based on the noise adjustment power, the human voice correction power, and the base power includes:

[0009] The noise adaptation power is obtained by summing the base power and the noise adjustment power, and the actual adjustment power is obtained by calculating the difference between the noise adaptation power and the human voice correction power.

[0010] Optionally, the audio amplifier power adjustment system further includes a dynamic audio management module;

[0011] The dynamic audio management module is used to process the environmental noise information to obtain noise sound pressure level information, and to process the voice input information to obtain voice input amplitude.

[0012] The main control module determines the noise adjustment power based on the noise sound pressure level information and the noise mapping relationship library, and is also used to determine the human voice correction power based on the voice input amplitude and the power correction rule library.

[0013] Optionally, the noise mapping database includes noise sound pressure level information, noise adjustment power, and preset noise signal-to-noise ratio, wherein the noise sound pressure level information, the noise adjustment power, and the preset noise signal-to-noise ratio have a one-to-one correspondence.

[0014] By calibrating the noise sound pressure level information at each level, the noise adjustment power corresponding to the preset signal-to-noise ratio of the corresponding level is obtained, and the noise mapping relationship library is obtained, wherein the level of the noise sound pressure level information is positively correlated with the preset signal-to-noise ratio of the noise.

[0015] Optionally, the power correction rule base includes the voice input amplitude, the voice correction power, and the preset signal-to-noise ratio for voice correction, wherein the voice input amplitude, the voice correction power, and the preset signal-to-noise ratio for voice correction are in a one-to-one correspondence.

[0016] The voice correction power is determined when the preset signal-to-noise ratio for voice correction is satisfied at each level of the voice input amplitude, thus obtaining the power correction rule library.

[0017] Optionally, the noise mapping relationship library includes a general mapping relationship library, a first mapping relationship library, and a second mapping relationship library; the noise mapping relationship library includes noise sound pressure level information, noise adjustment power, and noise preset signal-to-noise ratio, and the noise sound pressure level information, the noise adjustment power, and the noise preset signal-to-noise ratio have a one-to-one correspondence.

[0018] The first mapping relationship library corresponds to the first noise adjustment power, the general mapping relationship library corresponds to the general noise adjustment power, and the second mapping relationship library corresponds to the second noise adjustment power. The first noise adjustment power is greater than the general noise adjustment power, and the general noise adjustment power is greater than the second noise adjustment power.

[0019] Alternatively, the first mapping relationship library corresponds to a first noise preset signal-to-noise ratio, the general mapping relationship library corresponds to a general noise preset signal-to-noise ratio, and the second mapping relationship library corresponds to a second noise preset signal-to-noise ratio. The first noise preset signal-to-noise ratio is greater than the general noise preset signal-to-noise ratio, and the general noise preset signal-to-noise ratio is greater than the second noise preset signal-to-noise ratio.

[0020] Optionally, when the noise adjustment power is 0, under the same level of noise sound pressure level information, the first noise preset signal-to-noise ratio is the same as the second noise preset signal-to-noise ratio, and the first noise preset signal-to-noise ratio is the same as the general noise preset signal-to-noise ratio.

[0021] Optionally, the audio amplifier power adjustment system includes a first mode, which corresponds to the first mapping relationship library and the second mapping relationship library respectively; the first mode switches to correspond with the first mapping relationship library or the second mapping relationship library according to the duty cycle of low-frequency noise in different types of noise in the environmental noise information determined by the main control module and the magnitude of the first preset value.

[0022] Optionally, the audio amplifier power adjustment system further includes a dynamic audio management module;

[0023] The dynamic audio management module also includes a frequency filtering unit, which is used to detect the frequency of the ambient noise information.

[0024] In the first mode, when the frequency filtering unit detects that the duty cycle of low-frequency noise in the different types of noise is less than or equal to the first preset value, it switches the noise mapping relationship library to the first mapping relationship library; and when it detects that the duty cycle of low-frequency noise in the different types of noise is greater than the first preset value, it switches the noise mapping relationship library to the second mapping relationship library.

[0025] Optionally, the audio amplifier power adjustment system further includes a second mode, which corresponds to the general mapping relationship library;

[0026] In the second mode, the main control module adjusts the noise mapping relationship library to the general mapping relationship library.

[0027] Optionally, the audio amplifier power adjustment system further includes a dynamic audio management module;

[0028] The dynamic audio management module is also used to collect the actual playback sound pressure level information of the power amplifier module and convert the actual playback sound pressure level information into actual playback power.

[0029] The main control module receives the actual playback power, and determines the algorithm adjustment value based on the difference between the actual adjustment power and the actual playback power, and corrects the actual adjustment power based on the algorithm adjustment value.

[0030] Optionally, the main control module receives the actual playback sound pressure level information, calculates the actual signal-to-noise ratio (SNR) based on the actual playback sound pressure level information and the noise sound pressure level information, compares the actual SNR with the preset noise SNR, and if the actual SNR does not reach the preset noise SNR, then the algorithm adjustment value is re-determined according to the algorithm, and the actual adjustment power is corrected again according to the algorithm adjustment value until the actual SNR reaches the preset noise SNR.

[0031] In summary, the audio amplifier power adjustment system of the present invention includes a sound acquisition array, a main control module, and a power amplifier module. The sound acquisition array includes multiple sound acquisition units, which are located at different positions in the vehicle to collect environmental noise information and voice input information. The main control module is electrically connected to both the sound acquisition array and the power amplifier module. It is used to obtain the current vehicle's base power, determine the noise adjustment power based on the environmental noise information and a noise mapping library, and determine the human voice correction power based on the voice input information and a power correction rule library. The actual adjustment power is obtained based on the noise adjustment power, the human voice correction power, and the base power, and then sent to the power amplifier module. Thus, this application overcomes the limitations of traditional linear adjustment, enabling precise matching of the required signal-to-noise ratio gain according to different noise intensities. This not only improves the response speed and adaptation accuracy of power adjustment but also effectively avoids excessive power consumption or voice distortion caused by environmental misjudgment. Furthermore, by using the human voice correction power to perform non-linear correction of the base power, the output power exhibits adaptive adjustment in the frequency domain to human voice characteristics, thereby avoiding suppression of the human voice signal at the physical level and improving the user experience. Attached Figure Description

[0032] Figure 1 This is a simplified structural diagram of an audio power amplifier power adjustment system provided in an embodiment of the present invention;

[0033] Figure 2 This is a specific structural diagram of an audio power amplifier power adjustment system provided in an embodiment of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be fully described below with reference to the accompanying drawings in the embodiments of this invention, through specific implementation methods. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort fall within the protection scope of this invention.

[0035] Figure 1 This is a simplified structural diagram of an audio power amplifier power adjustment system provided in an embodiment of the present invention. See also... Figure 1 The audio power amplifier adjustment system includes a sound acquisition array 10, a main control module 20, and a power amplifier module 30. The sound acquisition array 10 includes multiple sound acquisition units (not shown in the figure), which are located at different positions within the vehicle to collect ambient noise information and voice input information. The main control module 20 is electrically connected to both the sound acquisition array 10 and the power amplifier module 30. It is used to obtain the vehicle's current base power, determine the noise adjustment power based on the ambient noise information and a noise mapping database, determine the voice correction power based on the voice input information and a power correction rule database, obtain the actual adjustment power based on the noise adjustment power, the voice correction power, and the base power, and then send the actual adjustment power to the power amplifier module 30.

[0036] Specifically, such as Figure 1As shown, the audio amplifier power adjustment system includes a sound acquisition array 10, a main control module 20, and an amplifier module 30. The sound acquisition array 10 can be a microphone array, and multiple sound acquisition units can be multiple microphone units. By placing multiple microphone units at different locations within the vehicle's cab, different sound information can be collected. For example, by placing microphone units near the noise source, environmental noise information of the vehicle can be collected; by placing microphone units near the driver or passengers, voice input information can be collected. Furthermore, the main control module 20 can obtain the vehicle's current base power. It can be understood that the vehicle itself may include 10 playback levels, each with a corresponding base power. As the playback level increases, the base power also increases. The main control module 20 can obtain the vehicle's current base power based on the vehicle's current playback level. Moreover, after receiving environmental noise information from the sound acquisition array 10, the main control module 20 determines the noise adjustment power based on the environmental noise information and a noise mapping database. Thus, the noise adjustment power is determined by using a noise mapping library. Since the noise mapping library includes noise mapping relationships of various levels, it is possible to achieve step-by-step adjustment of different noise intensities and meet the signal-to-noise ratio requirements of different noise intensities, ensuring the timeliness and adaptability of power adjustment. This application breaks through the limitations of traditional linear adjustment and can accurately match the required signal-to-noise ratio gain according to different noise intensities. It not only improves the response speed and adaptation accuracy of power adjustment, but also effectively avoids excessive power consumption or voice distortion caused by environmental misjudgment, significantly improving the overall performance of audio equipment in complex environments.

[0037] Furthermore, the main control module 20 can also receive voice input information sent by the sound acquisition array 10 and call the power correction rule library. Based on the voice input information and the power correction rule library, it obtains the human voice correction power. In addition to adjusting the base power through noise adjustment power, it adds adjustment of the human voice correction power. That is, when the presence of human voice communication intent or voice commands is detected in the vehicle, the human voice correction power is used to perform non-linear correction on the base power, so that the output power exhibits adaptive adjustment in the frequency domain for human voice characteristics. This avoids the suppression of human voice signals at the physical level, ensuring clear sound playback while avoiding suppression of human voice communication, balancing audio playback clarity and the voice interaction experience of drivers and passengers, preventing audio signals from interfering with voice command recognition, and the correction does not change the current gear of the vehicle system, thus improving the user experience. It is understood that users can enable or disable the adjustment of the human voice correction power as needed, and this embodiment of the invention does not impose any restrictions on this.

[0038] It should be noted that the noise mapping database can simulate vehicle noise in different environments (including different sound pressure levels and different frequency characteristics) using an on-board acoustic test bench. Using "the sound played by the power amplifier module can be clearly identified (the signal-to-noise ratio meets the preset requirements)" as the calibration standard, the absolute values ​​of power amplifier power adjustment under different noise conditions are collected. After multiple experiments and taking the average value, a basic correspondence is established. Then, combined with real vehicle road tests (urban roads, highways, rural roads, etc.), the basic data is corrected, and finally, an adaptable database that can be directly called is formed, namely the noise mapping database.

[0039] In summary, the audio amplifier power adjustment system of the present invention includes a sound acquisition array, a main control module, and a power amplifier module. The sound acquisition array includes multiple sound acquisition units, which are located at different positions in the vehicle to collect environmental noise information and voice input information. The main control module is electrically connected to both the sound acquisition array and the power amplifier module. It is used to obtain the current vehicle's base power, determine the noise adjustment power based on the environmental noise information and a noise mapping library, and determine the human voice correction power based on the voice input information and a power correction rule library. The actual adjustment power is obtained based on the noise adjustment power, the human voice correction power, and the base power, and then sent to the power amplifier module. Thus, this application overcomes the limitations of traditional linear adjustment, enabling precise matching of the required signal-to-noise ratio gain according to different noise intensities. This not only improves the response speed and adaptation accuracy of power adjustment but also effectively avoids excessive power consumption or voice distortion caused by environmental misjudgment. Furthermore, by using the human voice correction power to perform non-linear correction of the base power, the output power exhibits adaptive adjustment in the frequency domain to human voice characteristics, thereby physically avoiding suppression of the human voice signal and improving the user experience.

[0040] Optionally, based on the above embodiments, see also... Figure 1 The actual adjustment power is obtained based on the noise adjustment power, the voice correction power, and the base power. This includes obtaining the noise adaptation power by summing the base power and the noise adjustment power, and calculating the difference between the noise adaptation power and the voice correction power to obtain the actual adjustment power.

[0041] Specifically, the base power is the preset power at the current playback level. As the ambient noise level increases, the sound emitted by the amplifier module 30 at the base power may become inaudible to the user. This is because noise interference prevents the sound emitted by the amplifier module 30 from meeting the preset signal-to-noise ratio (SNR) requirement. Therefore, the power of the amplifier module 30 needs to be increased. The main control module 20 then calculates the noise adaptation power based on the sum of the base power and the noise adjustment power to reduce the impact of ambient noise. Furthermore, to meet the preset SNR, the noise adjustment power may be increased excessively, potentially suppressing human voice communication. Therefore, this embodiment of the invention also calculates the difference between the noise adaptation power and the human voice correction power. By increasing the noise adjustment power and subtracting the human voice correction power, the invention ensures clear sound playback while avoiding suppression of human voice communication, balancing audio playback clarity and the voice interaction experience for drivers and passengers, and preventing audio signal interference with voice command recognition.

[0042] Optionally, based on the above embodiments, Figure 2 This is a detailed structural diagram of an audio power amplifier power adjustment system provided in an embodiment of the present invention. See also... Figure 2 The power amplifier adjustment system also includes a dynamic audio management module 40. The dynamic audio management module 40 processes environmental noise information to obtain noise sound pressure level information and processes voice input information to obtain voice input amplitude. The main control module 20 determines the noise adjustment power based on the noise sound pressure level information and the noise mapping relationship library, and is also used to determine the human voice correction power based on the voice input amplitude and the power correction rule library.

[0043] Specifically, such as Figure 2As shown, the sound acquisition array 10 transmits the acquired environmental noise information to the dynamic audio management module 40 through the relay processing unit. The dynamic audio management module 40 receives the environmental noise information, performs noise reduction processing on the environmental noise information through a low-pass filter, and converts the analog signal environmental noise information into digital signal environmental noise information through analog-to-digital conversion. It then extracts the core parameters of the digital signal environmental noise information to calculate the noise sound pressure level information. In addition, the dynamic audio management module 40 is also used to extract the amplitude parameters of the voice input information, obtain the voice input amplitude, and transmit the voice input amplitude to the main control module 20. This allows the main control module 20 to determine the noise adjustment power based on the noise sound pressure level information and the noise mapping relationship library, and to determine the human voice correction power based on the voice input amplitude and power correction rule library. Through the settings of the dynamic audio management module 40, the conversion method of voice input information and environmental noise information can be kept simple. The built-in low-pass filter performs band-limiting processing on the analog signal, effectively eliminating high-frequency noise interference. Subsequently, through analog-to-digital conversion and core parameter extraction, the audio waveform data is converted into noise sound pressure level information and voice input amplitude that represent physical meaning. This not only greatly simplifies the data processing load of the main control module 20, allowing it to focus on intelligent decision-making based on the mapping library, but also shields the differences in front-end acquisition hardware through standardized data interfaces, significantly improving the system's anti-interference capability and cross-platform compatibility.

[0044] Optionally, based on the above embodiments, see also... Figure 2 The noise mapping database includes noise sound pressure level information, noise adjustment power, and preset noise signal-to-noise ratio (SNR). There is a one-to-one correspondence between the noise sound pressure level information, noise adjustment power, and preset SNR. The noise mapping database is obtained by calibrating the noise adjustment power corresponding to the preset SNR for each noise sound pressure level. The noise sound pressure level is positively correlated with the preset SNR.

[0045] Specifically, the noise mapping database includes the correspondence between noise sound pressure level information at multiple different levels, noise adjustment power, and preset noise signal-to-noise ratio (SNR). By calibrating the noise sound pressure level information for each level and determining the corresponding noise adjustment power that satisfies the preset SNR for that level, the noise mapping database is obtained. Furthermore, the noise sound pressure level information is positively correlated with the preset SNR; that is, the higher the noise sound pressure level information, the quieter the corresponding environment, and the larger the general preset SNR. For example, the noise mapping database may include a general mapping database, as shown in Table 1 below:

[0046] Table 1: General Mapping Relationship Library

[0047]

[0048] As shown in Table 1 above, each level of noise sound pressure level information has a corresponding universal noise adjustment power and a universal noise preset signal-to-noise ratio. After determining the current vehicle's base power, if the noise sound pressure level information sent by the dynamic audio management module 40 is within the range of 50dBA-60dBA, it indicates that the vehicle may be in a moderate noise environment, such as driving at low speed on urban roads. In this case, the main control module 20 determines the universal noise adjustment power to be 10W based on the noise sound pressure level information and the universal mapping relationship library. It then calculates the sum of the base power and the noise adjustment power to obtain the final noise adaptation power, ensuring that the current ambient noise information meets the universal noise preset signal-to-noise ratio (universal noise preset signal-to-noise ratio ≥ 15dB). By establishing a positive correlation between the noise sound pressure level information and the preset noise signal-to-noise ratio, it ensures that the system can output the precise power required to achieve the optimal listening signal-to-noise ratio under different levels of ambient noise. This lookup-table control logic based on hierarchical calibration, compared to traditional linear gain algorithms, can more accurately balance vocal clarity and environmental noise suppression, effectively avoiding overshoot or undershoot during volume adjustment and significantly improving the consistency of the user experience. As shown in Table 1, in the general mapping library, when the main control module 20 detects noise sound pressure level information within the range of 0dBA - 40dBA or 40dBA - 40dBA, no noise power adjustment is required; that is, the determined general noise adjustment power is 0. At this time, the current environmental noise information already meets the corresponding preset signal-to-noise ratio requirements.

[0049] It should be noted that the above embodiments are only illustrative examples of noise mapping relation libraries including general mapping relation libraries, but are not intended to limit the scope of the embodiments. In other embodiments, the noise mapping relation library may also include a first mapping relation library and a second mapping relation library, which can be configured as needed by those skilled in the art.

[0050] Optional, see below Figure 2 The power correction rule base includes the voice input amplitude, voice correction power, and voice correction preset signal-to-noise ratio. The voice input amplitude, voice correction power, and voice correction preset signal-to-noise ratio are in one-to-one correspondence. The voice correction power corresponding to the voice correction preset signal-to-noise ratio at each level of voice input amplitude is calibrated to obtain the power correction rule base.

[0051] Specifically, such as Figure 2As shown, the sound acquisition array 10 can also acquire the user's voice input information and transmit it to the dynamic audio management module 40. The dynamic audio management module 40 extracts the amplitude parameters of the voice input information to obtain the voice input amplitude and transmits it to the main control module 20. The main control module 20 calls the power correction rule library and obtains the voice correction power based on the voice input amplitude and the power correction rule library. The power correction rule library includes the correspondence between multiple different levels of voice input amplitude, voice correction power, and preset signal-to-noise ratio for voice correction. Through calibration, the corresponding voice correction power can be determined to achieve the corresponding preset signal-to-noise ratio requirement for voice correction at each level of voice input amplitude, resulting in multiple sets of correspondences and thus the power correction rule library. For example, the power correction rule library can be shown in Table 2 below:

[0052] Table 2: Power Correction Rule Base

[0053]

[0054] As shown in Table 2 above, after receiving the voice input amplitude, the main control module 20 determines that the voice correction power is 0 when the voice input amplitude is within the range of 0-1, meaning no correction is needed. When the voice input amplitude is within the range of 1-2, it indicates that the playback volume of the power amplifier module 30 is too loud, suppressing human voice communication. Therefore, the voice correction power is set to 10W. The difference between the noise adaptation power and the voice correction power is calculated, and the noise adaptation power is reduced to obtain the actual adjustment power. This ensures clear playback while avoiding suppression of human voice communication. Table 2 shows that the larger the voice input amplitude, the greater the reduction in noise adaptation power (voice correction power). Thus, this invention achieves refined gain management of human voice signals by constructing a three-dimensional power correction rule base that includes voice input amplitude, voice correction power, and a preset signal-to-noise ratio for voice correction. Specifically, by calibrating the amplitude of different levels of voice input, the precise correction power required to achieve optimal human voice listening experience is established, effectively overcoming the problem of fluctuating volume or distortion of human voice caused by environmental noise fluctuations in traditional automatic gain control. Simultaneously, combined with the aforementioned noise mapping database, the main control module 20 can make collaborative decisions based on both environmental noise and human voice amplitude inputs, ensuring that the output audio maintains constant clarity and comfort under various extreme acoustic environments, significantly improving the system's robustness.

[0055] Optionally, based on the above embodiments, see also... Figure 2The noise mapping database includes a general mapping database, a first mapping database, and a second mapping database. The noise mapping database includes noise sound pressure level information, noise adjustment power, and preset noise signal-to-noise ratio (SNR). There is a one-to-one correspondence between the noise sound pressure level information, noise adjustment power, and preset noise SNR. The first mapping database corresponds to the first noise adjustment power, the general mapping database corresponds to the general noise adjustment power, and the second mapping database corresponds to the second noise adjustment power. The first noise adjustment power is greater than the general noise adjustment power, and the general noise adjustment power is greater than the second noise adjustment power. Alternatively, the first mapping database corresponds to the first preset noise SNR, the general mapping database corresponds to the general noise preset SNR, and the second mapping database corresponds to the second preset noise SNR. The first preset noise SNR is greater than the general preset noise SNR, and the general preset noise SNR is greater than the second preset noise SNR.

[0056] Specifically, the noise mapping library includes a general mapping library, a first mapping library, and a second mapping library. The general mapping library does not distinguish between frequency differences; all types of noise can be used to determine the noise adjustment power. The first mapping library can be a mapping library for first-frequency noise, which can be mid-to-high frequency noise. The characteristic frequency of mid-to-high frequency noise can be greater than 2kHz, such as wind noise or high-speed tire noise. The second mapping library can be a mapping library for second-frequency noise, which can be low-frequency noise. The characteristic frequency of low-frequency noise can be less than or equal to 2kHz, such as engine idling noise or low-frequency tire noise. The first mapping library is shown in Table 3 below.

[0057] Table 3: First Mapping Relationship Database

[0058]

[0059] Combining Tables 1 and 3, it can be seen that the noise sound pressure level information classification is the same in the general mapping relation library and the first mapping relation library. However, the noise adjustment power and preset signal-to-noise ratio corresponding to the same noise sound pressure level information are different. For example, since a higher signal-to-noise ratio is required under mid-to-high frequency noise to make the played sound clearly distinguishable, under the same noise sound pressure level information, the first noise preset signal-to-noise ratio corresponding to the first mapping relation library is greater than the general preset signal-to-noise ratio in the general mapping relation library, or the first noise adjustment power corresponding to the first mapping relation library is greater than the general noise adjustment power in the general mapping relation library. This invention breaks the single-dimensional limitation of traditional noise reduction. In scenarios where a specific noise frequency exists, the system calls the first mapping relation library to provide a first noise adjustment power higher than that of the general mapping relation library or a higher first noise preset signal-to-noise ratio. In this way, differentiated adaptation is achieved according to the noise frequency characteristics, solving the technical contradiction that high-definition sound quality and long battery life cannot be achieved simultaneously.

[0060] Furthermore, the second mapping relation library can be shown in Table 4 below:

[0061] Table 4: Second Mapping Relationship Database

[0062]

[0063] Combining Tables 1 and 4, it can be seen that the noise sound pressure level information classification is the same in the general mapping relation library and the second mapping relation library. However, the noise adjustment power and the preset noise signal-to-noise ratio corresponding to the same noise sound pressure level information are different. For example, since a lower signal-to-noise ratio is required under low-frequency noise to make the played sound clearly distinguishable, the preset signal-to-noise ratio of the second noise in the second mapping relation library is set to be lower than the preset signal-to-noise ratio of the general noise in the general mapping relation library, or the preset signal-to-noise power of the second noise in the second mapping relation library is set to be lower than the general noise adjustment power in the general mapping relation library, so as to achieve differentiated adaptation according to the noise frequency characteristics, which is beneficial to saving power consumption.

[0064] It should be noted that when the noise adjustment power is 0, under the same level of noise sound pressure level information, the first noise preset signal-to-noise ratio and the second noise preset signal-to-noise ratio are the same, and the first noise preset signal-to-noise ratio is the same as the general noise preset signal-to-noise ratio. Specifically, refer to Tables 1, 3, and 4. Under extremely quiet (0-40) and quiet (40-50) noise sound pressure level information, the noise adjustment power corresponding to the general mapping relation library, the first mapping relation library, and the second mapping relation is all 0. That is, under quiet and extremely quiet noise sound pressure level information, no noise adjustment is required. At this time, under the same level of noise sound pressure level information, the first noise preset signal-to-noise ratio and the second noise preset signal-to-noise ratio are the same, and the first noise preset signal-to-noise ratio is the same as the general noise preset signal-to-noise ratio. This simplifies the processing logic and improves processing efficiency and consistency while maximizing the guarantee of voice quality and clarity.

[0065] It should also be noted that the correspondences in the general mapping relationship library, the first mapping relationship library, and the second mapping relationship library mentioned above are all calibrated based on data of one type of vehicle. This invention does not limit this. In actual use, those skilled in the art can perform actual calibration according to different types of vehicles.

[0066] Optional, see below Figure 2 The audio amplifier power adjustment system includes a first mode, which corresponds to a first mapping relationship library and a second mapping relationship library respectively. The first mode switches to correspond with the first mapping relationship library or the second mapping relationship library based on the duty cycle of low-frequency noise in different types of noise in the environmental noise information judged by the main control module 20 and the relationship with the first preset value. The first preset value can be 40%.

[0067] For example, such as Figure 2As shown, the power adjustment of the audio amplifier power adjustment system can include a first mode. The first mode can be a working mode that distinguishes frequency differences, mainly using a first mapping relationship library and a second mapping relationship library. In the first mode, the main control module 20 judges the duty cycle of low-frequency noise in different types of environmental noise information and switches the noise mapping relationship library to the first mapping relationship library or the second mapping relationship library based on the relationship between the duty cycle and a first preset value. Specifically, the dynamic audio management module 40 also includes a frequency filtering unit, which is used to detect the frequency of environmental noise information. Different types of noise can include mid-to-high frequency noise and low-frequency noise. Among them, mid-to-high frequency noise can be wind noise or high-speed tire noise, and low-frequency noise can be engine idling or low-frequency tire noise. The first preset value is determined based on the duty cycle of low-frequency noise. In this embodiment, a first preset value of 40% is used as an example. In the first mode, if the frequency filtering unit detects a low-frequency noise duty cycle of 30% among different types of noise, since 30% is less than or equal to the first preset value of 40%, it indicates that the scene is mainly dominated by mid-to-high frequency noise. Therefore, the noise mapping relation library is switched to the first mapping relation library. The correspondence of the first mapping relation library differs from that of the general mapping relation library. Compared to the general relation library, the first mapping relation library is more suitable for mid-to-high frequency noise. The main control module 20 then determines the first noise adjustment power based on the noise sound pressure level information and the first mapping relation library, and obtains the noise adaptation power based on the sum of the first noise adjustment power and the base power. Similarly, if the frequency filtering unit detects a low-frequency noise duty cycle of 40% among different types of noise, since 40% is the same as the first preset value of 40%, it indicates that the scene is mainly dominated by mid-to-high frequency noise. Therefore, the noise mapping relation library is switched to the first mapping relation library. If the frequency filtering unit detects that the duty cycle of low-frequency noise is 50% among different types of noise, and since 50% is greater than the first preset value of 40%, it indicates that low-frequency noise is the main component in this scenario. Therefore, the noise mapping library is switched to the second mapping library. The correspondence in the second mapping library differs from that in the general mapping library. Compared to the general mapping library, the second mapping library is more suitable for low-frequency noise. The main control module 20 then determines the second noise adjustment power based on the noise sound pressure level information and the second mapping library, and obtains the noise adaptation power based on the sum of the second noise adjustment power and the base power. It is understood that the above embodiment is only illustrative, using the first preset value of 40% as an example. In actual vehicle manufacturing or equipment debugging, the magnitude of the first preset value can be adjusted according to the sound insulation of different vehicle models, real noise data, and passenger experience.For vehicles with excellent sound insulation, the first preset value needs to be appropriately increased because mid-to-high frequency noise decays quickly and low-frequency noise accounts for a relatively high proportion. Conversely, for vehicles with weak sound insulation, the first preset value needs to be decreased. Furthermore, the first preset value can be modified based on the actual experience of passengers. Therefore, this invention does not limit the specific data of the first preset value, and those skilled in the art can set it according to actual usage needs.

[0068] Thus, this embodiment of the invention achieves frequency-domain adaptive audio power adjustment by introducing a first mode and a frequency filtering unit. Specifically, by real-time monitoring of the duty cycle of low-frequency noise in the ambient noise and comparing it with a first preset value of 40%, the dominant frequency component of the current sound field can be determined. When mid-to-high frequency noise is determined to be dominant, a more adaptable first mapping relation library is invoked to provide precise mid-to-high frequency gain; when low-frequency noise is determined to be dominant, the system switches to a second mapping relation library to provide targeted low-frequency compensation. This duty cycle-triggered dual-library switching mechanism breaks the single-dimensional limitation of traditional noise reduction relying solely on sound pressure level, effectively solving the problem of muddy sound due to low-frequency masking effects. Simultaneously, it avoids ineffective power loss in non-dominant frequency bands, saving energy while ensuring a satisfactory signal-to-noise ratio.

[0069] It should be noted that the power adjustment of the audio amplifier power adjustment system can also include a second mode. This second mode can be a standard default mode, meaning it does not require switching based on noise frequency. The second mode corresponds to a general mapping library. In this second mode, the main control module 20 adjusts the noise mapping library to the general mapping library. This embodiment of the invention, by setting a dual-mode adjustment mechanism including both a first and a second mode, balances the accuracy of intelligent adjustment with the stability of system operation. The second mode, as the standard default mode, directly calls the general mapping library, providing a reliable benchmark reference for the system and effectively reducing system computing power consumption. It is understood that users can switch between the first and second modes according to their actual usage needs.

[0070] Optionally, based on the above embodiments, the audio amplifier power adjustment system further includes a dynamic audio management module 40. The dynamic audio management module 40 is also used to collect the actual playback sound pressure level information of the amplifier module 30 and convert the actual playback sound pressure level information into actual playback power. The main control module 20 receives the actual playback power and uses an algorithm to determine the algorithm adjustment value based on the difference between the actual adjustment power and the actual playback power, and corrects the actual adjustment power according to the algorithm adjustment value.

[0071] Specifically, the sound acquisition array 10 can also acquire the actual playback sound pressure level information of the power amplifier module 30 and transmit the actual playback sound pressure level information to the dynamic audio management module 40. After receiving the actual playback sound pressure level information, the dynamic audio management module 40 converts the actual playback sound pressure level information into actual playback power and transmits the actual playback power to the main control module 20. The main control module 20 has a built-in PID algorithm, which can use the difference between the actual adjustment power calculated in the previous steps and the actual playback power as the deviation input e(t) of the PID algorithm. Combined with the preset PID parameters (Kp=0.8, Ki=0.2, Kd=0.1), the algorithm adjustment value is calculated through the core PID formula, and the actual adjustment power is corrected according to the algorithm adjustment value, thereby achieving smooth and accurate power correction. The core logic of the PID algorithm is: Proportional element (P): Directly outputs the adjustment amount Kp×e(t) according to the magnitude of the deviation input e(t), quickly responding to sudden changes in environmental noise and speech, such as a sudden increase in wind noise when driving at high speed, immediately outputting the power increment to ensure the clarity of the playback sound. Integral stage (I): Integrates the deviation input e(t) over time ∫Ki×e(t)dt to eliminate static deviations. For example, when the ambient noise is stable at 60dB, it eliminates minor errors in power adjustment, ensuring that the final adjusted power perfectly matches the target adjusted power. Differential stage (D): Differentiates the deviation input e(t) by Kd×e(t) / dt to suppress dynamic overshoot. For example, when a vehicle moves from a quiet road to a noisy road, it avoids sudden power fluctuations that could cause auditory discomfort, achieving a smooth increase or decrease in power. Power constraint ensures that the target adjusted power is within a set range (e.g., 0-320W). Thus, by adjusting the deviation value through the algorithm, auditory discomfort caused by sudden power fluctuations can be avoided, minor adjustment errors can be eliminated, and the actual power can perfectly match the target power, improving the smoothness and accuracy of power adjustment, while strictly limiting the overall power of the power amplifier module 30 to not exceed the rated value.

[0072] It should be noted that the above embodiments are only illustrative examples of the PID algorithm, but are not intended to limit the scope of the embodiments. In other embodiments, fuzzy control algorithms can also be used for algorithm modification, and those skilled in the art can set them as needed.

[0073] Optionally, based on the above embodiments, see also... Figure 1 The main control module 20 receives the actual playback sound pressure level information and calculates the actual signal-to-noise ratio based on the actual playback sound pressure level information and the noise sound pressure level information. It compares the actual signal-to-noise ratio with the preset noise signal-to-noise ratio. If the actual signal-to-noise ratio does not meet the preset noise signal-to-noise ratio requirement, it re-determines the algorithm adjustment value according to the algorithm and corrects the actual adjustment power again according to the algorithm adjustment value until the actual signal-to-noise ratio reaches the preset noise signal-to-noise ratio.

[0074] Specifically, the sound acquisition array 10 can also acquire the actual playback sound pressure level information of the power amplifier module 30 and transmit the actual playback sound pressure level information to the dynamic audio management module 40. The main control module 20 receives the actual playback sound pressure level information and noise sound pressure level information fed back by the dynamic audio management module 40, and calculates the actual signal-to-noise ratio based on the actual playback sound pressure level information and noise sound pressure level information. In addition, the main control module 20 also determines the preset noise signal-to-noise ratio based on the noise sound pressure level information. For example, as shown in Tables 1, 3 and 4, when the noise sound pressure level information is in the range of 50dBA-60dBA, the preset general noise signal-to-noise ratio corresponding to the general mapping relationship library is 15dB, the preset first noise signal-to-noise ratio corresponding to the first mapping relationship library is 18dB, and the preset second noise signal-to-noise ratio corresponding to the second mapping relationship library is 12dB. The actual signal-to-noise ratio (SNR) is compared with the preset SNR under the corresponding conditions. If the actual SNR does not reach the preset SNR, the algorithm adjustment value is re-determined based on the algorithm, and the designed power adjustment is corrected again based on the algorithm adjustment value until the actual SNR reaches the preset SNR. Thus, this invention constructs a dynamic closed-loop control system for audio power adjustment by introducing a feedback mechanism based on the actual playback sound pressure level. By comparing the actual SNR with the target preset SNR in real time, the system can automatically generate an algorithm adjustment value to iteratively correct the output power until the two match. This effectively eliminates model mismatch errors caused by speaker aging, changes in vehicle body sealing, or sudden environmental changes, ensuring that the in-vehicle audio output is strictly locked within the preset optimal listening range under different lifecycles and usage environments, significantly improving the system's robustness and long-term reliability.

[0075] Optionally, based on the above embodiments, see also... Figure 2 The audio power amplifier power adjustment system also includes an audio processing module 50. The sound acquisition array 10 is electrically connected to the dynamic audio management module 40 through the audio processing module 50. The audio processing module 50 processes the environmental noise information and transmits it to the dynamic audio management module 40. The main control module 20 is connected to the power amplifier module 30 through the audio processing module 50. The power amplifier module 30 includes a multi-channel power amplifier module and a multi-channel speaker module. The main control module 20 converts the actual adjustment power into a power adjustment command and sends the power adjustment command to the audio processing module 50. The audio processing module 50 allocates power to the multi-channel power amplifier module according to the power adjustment command, so that the multi-channel power amplifier module drives the multi-channel speaker module to produce sound.

[0076] Specifically, the sound acquisition array 10 can be connected to the audio processing module 50 via an A2B bus, and the audio processing module 50 can be connected to the dynamic audio management module 40 via an I2S bus, thereby enabling audio stream transmission between the sound acquisition array 10 and the dynamic audio management module 40. Furthermore, the power amplifier module 30 includes a multi-channel power amplifier module and a multi-channel speaker module. For example, the multi-channel power amplifier module can be a 16-channel power amplifier (320W), and the multi-channel speaker module can be a 16-channel speaker module. In one embodiment, the total power adjustment limit of the power amplifier module 30 is 320W. The main control module 20 limits the actual adjusted power obtained above to less than or equal to 320W. The main control module 20 converts the actual adjusted power into a power adjustment command and sends the power adjustment command to the audio processing module 50. The audio processing module 50 allocates power to the 16 channels of the multi-channel power amplifier module according to the power adjustment command, ensuring that the single-channel gain matching power requirement is ≤20W, thereby ensuring the normal adjustment of the main control module 20. It is understood that the power distribution of the audio processing module 50 can be an average distribution or a distribution based on regional differences. This embodiment of the invention does not limit this, and those skilled in the art can set it as needed.

[0077] Optionally, based on the above embodiments, see also... Figure 2 The sound acquisition array 10 includes multiple microphone units (not shown in the figure). These microphone units include a first microphone unit and a second microphone unit. The first microphone unit is used to acquire ambient noise information, and the second microphone unit is used to acquire voice input information. The first microphone unit is located on the top front side of the driver's cabin or near the door. The second microphone unit is located near the center console area of ​​the vehicle.

[0078] Specifically, the multiple microphone units in this embodiment of the invention can be arranged in a distributed manner. For example, two first microphone units are set on the top front side of the driver's cabin in the vehicle to collect forward environmental noise (such as wind noise or traffic noise in front) during vehicle operation. One first microphone unit is arranged near each of the four door speakers to collect side environmental noise (such as tire noise, side vehicle noise) and sound pressure feedback signals played by the speakers. Two second microphone units are set on both sides of the central control area (next to the air conditioning vents) to collect voice input signals (communication, voice commands) of the driver and passengers in the driver's cabin. In this way, functional zone acquisition can be realized, providing accurate data for multi-parameter analysis and adapting to the power adjustment requirements of multi-channel power amplifiers. In addition, all microphone units are installed in an embedded snap-on manner, fitting snugly with the vehicle interior, and connected to the A2B communication bus interface through shielded wires to reduce vehicle electromagnetic interference. The output end of the sound acquisition array 10 is connected to the input end of the audio processing module 50 through the A2B communication bus to realize low-latency, high-fidelity multi-channel signal synchronous transmission.

[0079] Optionally, based on the above embodiments, see also... Figure 2 The audio amplifier power adjustment system also includes a vehicle-mounted unit module 60, which is connected to the main control module 20. The vehicle-mounted unit module 60 sends the current playback level information to the main control module 20, and the main control module 20 determines the base power based on the current playback level information and the corresponding level relationship.

[0080] Specifically, in one embodiment, the vehicle infotainment module 60 has 10 playback levels. The vehicle infotainment module 60 can connect to the main control module 20 via CAN BUS. After adjusting the playback level via the vehicle infotainment module 60, it sends the current playback level information to the main control module 20. The main control module 20 determines the base power based on the current playback level information and the level correspondence. For example, taking the overall base power of the power amplifier module 30 as an example, the level correspondence can be shown in Table 5 below:

[0081] Table 5: Gearbox Correspondence

[0082]

[0083] As shown in Table 5 above, after the vehicle infotainment module 60 adjusts the current playback level to 5, it sends this information to the main control module 20. The main control module 20 then determines the base power to be 128W based on the current playback level and its corresponding relationship, using this base power for subsequent noise adaptation power calculations. Furthermore, the vehicle infotainment module 60 also provides a user interface and receives and visualizes system operating data.

[0084] Optional, see below Figure 2 The audio amplifier power adjustment system also includes a storage module 70, which is electrically connected to the main control module 20. The storage module 70 is used to store a noise mapping relationship library and a power correction rule library. In addition, the storage module 70 can also store the gear correspondence, so that the main control module 20 can retrieve the corresponding data when needed. The storage module 70 can be a FLASH storage module or an EEPROM storage module. The present invention does not limit it. It should be noted that when the storage module 70 is an EEPROM storage module, it can be used to store a database with a small amount of data, such as storing only a general mapping relationship library.

[0085] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. An audio power amplifier power adjustment system, characterized in that, The audio power amplifier power adjustment system includes a sound acquisition array, a main control module, and a power amplifier module. The sound acquisition array includes multiple sound acquisition units, which are located at different positions in the vehicle and are used to collect environmental noise information and voice input information. The main control module is electrically connected to the sound acquisition array and the power amplifier module respectively. It is used to obtain the current vehicle's base power, determine the noise adjustment power according to the environmental noise information and noise mapping relationship library, determine the human voice correction power according to the voice input information and power correction rule library, obtain the actual adjustment power according to the noise adjustment power, the human voice correction power and the base power, and send the actual adjustment power to the power amplifier module.

2. The audio amplifier power adjustment system according to claim 1, characterized in that, The actual adjustment power is obtained based on the noise adjustment power, the human voice correction power, and the base power, including: The noise adaptation power is obtained by summing the base power and the noise adjustment power, and the actual adjustment power is obtained by calculating the difference between the noise adaptation power and the human voice correction power.

3. The audio amplifier power adjustment system according to claim 1, characterized in that, The audio amplifier power adjustment system also includes a dynamic audio management module; The dynamic audio management module is used to process the environmental noise information to obtain noise sound pressure level information, and to process the voice input information to obtain voice input amplitude. The main control module determines the noise adjustment power based on the noise sound pressure level information and the noise mapping relationship library, and is also used to determine the human voice correction power based on the voice input amplitude and the power correction rule library.

4. The audio amplifier power adjustment system according to claim 3, characterized in that, The noise mapping database includes noise sound pressure level information, noise adjustment power, and preset noise signal-to-noise ratio, and the noise sound pressure level information, the noise adjustment power, and the preset noise signal-to-noise ratio have a one-to-one correspondence. By calibrating the noise sound pressure level information at each level, the noise adjustment power corresponding to the preset signal-to-noise ratio of the corresponding level is obtained, and the noise mapping relationship library is obtained, wherein the level of the noise sound pressure level information is positively correlated with the preset signal-to-noise ratio of the noise.

5. The audio amplifier power adjustment system according to claim 3, characterized in that, The power correction rule base includes voice input amplitude, voice correction power, and voice correction preset signal-to-noise ratio, and the voice input amplitude, the voice correction power, and the voice correction preset signal-to-noise ratio have a one-to-one correspondence. The voice correction power is determined when the preset signal-to-noise ratio for voice correction is satisfied at each level of the voice input amplitude, thus obtaining the power correction rule library.

6. The audio power amplifier power adjustment system according to claim 1, characterized in that, The noise mapping relationship library includes a general mapping relationship library, a first mapping relationship library, and a second mapping relationship library; the noise mapping relationship library includes noise sound pressure level information, noise adjustment power, and noise preset signal-to-noise ratio, and the noise sound pressure level information, the noise adjustment power, and the noise preset signal-to-noise ratio have a one-to-one correspondence. The first mapping relationship library corresponds to the first noise adjustment power, the general mapping relationship library corresponds to the general noise adjustment power, and the second mapping relationship library corresponds to the second noise adjustment power. The first noise adjustment power is greater than the general noise adjustment power, and the general noise adjustment power is greater than the second noise adjustment power. Alternatively, the first mapping relationship library corresponds to a first noise preset signal-to-noise ratio, the general mapping relationship library corresponds to a general noise preset signal-to-noise ratio, and the second mapping relationship library corresponds to a second noise preset signal-to-noise ratio. The first noise preset signal-to-noise ratio is greater than the general noise preset signal-to-noise ratio, and the general noise preset signal-to-noise ratio is greater than the second noise preset signal-to-noise ratio.

7. The audio amplifier power adjustment system according to claim 6, characterized in that, When the noise adjustment power is 0, under the same level of noise sound pressure level information, the first noise preset signal-to-noise ratio is the same as the second noise preset signal-to-noise ratio, and the first noise preset signal-to-noise ratio is the same as the general noise preset signal-to-noise ratio.

8. The audio amplifier power adjustment system according to claim 6, characterized in that, The audio amplifier power adjustment system includes a first mode, which corresponds to the first mapping relationship library and the second mapping relationship library respectively. The first mode switches to correspond with the first mapping relationship library or the second mapping relationship library according to the duty cycle of low-frequency noise in different types of noise in the environmental noise information determined by the main control module and the magnitude of the first preset value.

9. The audio power amplifier power adjustment system according to claim 8, characterized in that, The audio amplifier power adjustment system also includes a dynamic audio management module; The dynamic audio management module also includes a frequency filtering unit, which is used to detect the frequency of the ambient noise information. In the first mode, when the frequency filtering unit detects that the duty cycle of low-frequency noise in different types of noise is less than or equal to the first preset value, it switches the noise mapping relationship library to the first mapping relationship library; and when it detects that the duty cycle of low-frequency noise in different types of noise is greater than the first preset value, it switches the noise mapping relationship library to the second mapping relationship library.

10. The audio power amplifier power adjustment system according to claim 6, characterized in that, The power amplifier power adjustment system also includes a second mode, which corresponds to the general mapping relationship library; In the second mode, the main control module adjusts the noise mapping relationship library to the general mapping relationship library.

11. The audio power amplifier power adjustment system according to claim 1, characterized in that, The audio amplifier power adjustment system also includes a dynamic audio management module; The dynamic audio management module is also used to collect the actual playback sound pressure level information of the power amplifier module and convert the actual playback sound pressure level information into actual playback power. The main control module receives the actual playback power, and uses an algorithm to determine an algorithm adjustment value based on the difference between the actual adjusted power and the actual playback power. The actual adjusted power is then corrected based on the algorithm adjustment value.

12. The audio power amplifier power adjustment system according to claim 11, characterized in that, The dynamic audio management module is also used to process the environmental noise information to obtain noise sound pressure level information; The main control module receives the actual playback sound pressure level information and calculates the actual signal-to-noise ratio (SNR) based on the actual playback sound pressure level information and the noise sound pressure level information. It then compares the actual SNR with the preset noise SNR. If the actual SNR does not reach the preset noise SNR, the algorithm adjustment value is re-determined according to the algorithm, and the actual adjustment power is corrected again according to the algorithm adjustment value until the actual SNR reaches the preset noise SNR.

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