Sound signal generating device frequency response adjusting system and method based on multi-sensing data acquisition

Abstract

The invention discloses an acoustic signal generation device frequency response adjusting system and method based on multi-sensor data acquisition, relates to the technical field of acoustic measurement calibration, and solves the problem that in the prior art, the cost of a correction system is too high due to the fact that an acoustic signal meets the requirement of a first-level acoustic calibrator. The system comprises a sensor unit, a main control unit, a digital-to-analog converter, an operational amplifier and a coupling cavity internally provided with a loudspeaker, the main control unit can control the magnitude of an output signal of the digital-to-analog converter based on a preset sound pressure compensation algorithm according to the air pressure, the temperature and the humidity of a use environment, generate a pure tone signal with specified frequency and amplitude and adjust frequency response, and an expensive 1-grade or LS-grade microphone does not need to be adopted. And a collection circuit does not need to be designed and a sound pressure level does not need to be calculated in a hardware circuit, so that the production cost of the system can be reduced on the premise of realizing multi-frequency-point and multi-sound-pressure-level calibration.

Description

Technical Field

[0001] This application relates to the technical field of acoustic metrology calibration, and in particular to a frequency response adjustment system and method for an acoustic signal generating device based on multi-sensor data acquisition. Background Technique

[0002] An acoustic signal generating device is a type of acoustic calibrator, mainly used for the periodic calibration of acoustic measurement instruments such as sound level meters and for the frequency response detection of test microphones. Common acoustic calibration methods mainly include piston sound generators, acoustic calibrators with negative feedback, etc.

[0003] Piston sound generator: An acoustic calibrator that generates sound pressure in a fixed air volume through the movement of one or more pistons with a known volume velocity. The piston is driven by a motor to reciprocate in the cavity, thereby changing the pressure in the cavity and generating sound. Although the sound pressure is stable and can achieve Class 1 or even LS Class, it has the following defects:

[0004] (1) Friction and wear, which easily lead to the aging of seals and air leakage;

[0005] (2) Nonlinear distortion. When the piston displacement exceeds the linear region, second harmonic distortion is likely to occur, and at the same time, the rapid movement of the piston causes airflow noise;

[0006] (3) The piston is relatively sensitive to temperature and humidity, which easily causes distortion and changes in sound pressure level;

[0007] (4) Limited by the motor speed, the frequency can usually only reach 250 Hz, and the application range is limited.

[0008] An acoustic calibrator with negative feedback can perform calibration at multiple sound pressure levels and multiple frequencies, but it has the following defects:

[0009] (1) Inherent defects of the feedback system. Signal processing in the feedback loop, such as analog-to-digital conversion and signal conditioning, will introduce a delay of 0.1 - 5 ms, resulting in phase distortion in the high-frequency band;

[0010] (2) Defects dependent on the microphone. The stability of the reference microphone directly causes the output sound pressure level to shift, and the microphone is affected by temperature, which will cause the feedback system to misjudge the sound pressure and overshoot;

[0011] (3) Defects in environmental adaptability. First, there is no air pressure compensation. When used on the plateau, the decrease in air density will cause changes in acoustic impedance, resulting in changes in the output sound pressure level. Second, it is greatly affected by environmental noise. When the signal-to-noise ratio deteriorates, it will cause the feedback system to misadjust;

[0012] (4) To implement a Class 1 sound calibrator, a Class 1 or LS-class microphone is required for negative feedback, resulting in high costs and expensive prices. Moreover, when using a microphone for negative feedback, a signal acquisition and conditioning circuit needs to be designed to analyze and calculate the acoustical measurements of the acquired signals. This is equivalent to implementing a sound level meter while achieving sound signal output within the device, leading to a complex overall solution and low reliability.

[0013] With the development of the noise measurement field, to ensure measurement accuracy, it is often necessary to calibrate acoustical measurement instruments such as sound level meters at multiple frequency points and multiple sound pressure levels. To achieve this goal, there is an urgent need for a frequency response adjustment system with low cost and stability for multiple frequency points and multiple sound pressure levels. Summary of the Invention

[0014] The purpose of this application is to overcome the problem of excessive cost of the correction system caused by the need to make the sound signal meet the requirements of a Class 1 sound calibrator in the prior art, and to provide a frequency response adjustment system and method for a sound signal generating device based on multi-sensor data acquisition.

[0015] In the first aspect, a frequency response adjustment system for a sound signal generating device based on multi-sensor data acquisition is provided, including:

[0016] A sensor unit for detecting the air pressure, temperature, and humidity of the usage environment and transmitting them to the main control unit;

[0017] A main control unit for controlling the magnitude of the signal output by the digital-to-analog converter, generating a pure tone signal with a specified frequency and amplitude, adjusting the frequency response, and storing the compensation parameters of each frequency point under reference environmental conditions based on a preset sound pressure compensation algorithm;

[0018] A digital-to-analog converter for converting the pure tone signal generated by the main control unit into an analog signal;

[0019] An operational amplifier for controlling the amplitude of the output signal through the DC signal of the main control unit and converting the analog signal from a single-ended signal to a differential signal for output to a speaker in the coupling cavity for sound signal output;

[0020] A coupling cavity for converting the differential signal into a sound signal through an internal speaker.

[0021] In some possible implementation manners, a power management unit is further included. The power management unit includes a first DC-DC boost circuit and a second DC-DC boost circuit. Among them, the first DC-DC boost circuit is used to convert the input power into a first specified voltage to supply power to the sensor unit and the main control unit, and the second DC-DC boost circuit is used to convert the input power into a second specified voltage to supply power to the digital-to-analog converter and the operational amplifier.

[0022] In some possible implementations, the power management unit further includes an input protection circuit. The input protection circuit includes a PMOS transistor. The source of the PMOS transistor is connected to the positive electrode of the power supply through a first resistor, a diode, and a thin film switch connected in series in sequence. A second resistor is connected in series between the gate and the source of the PMOS transistor. The gate of the PMOS transistor is connected to the collector of an NPN transistor through a third resistor. The drain of the PMOS transistor is connected to VUSB through a zener diode. The emitter of the NPN transistor is connected to the negative electrode of the power supply. The base of the NPN transistor is connected to the IO pin of the main control unit through a fourth resistor. The base of the NPN transistor is also connected to the negative electrode of the power supply through a fifth resistor. A tantalum electrolytic capacitor, a ceramic capacitor, and a transient voltage suppression diode are connected in parallel between the drain of the PMOS transistor and the negative electrode of the power supply, and the negative electrode of the power supply is grounded.

[0023] In some possible implementations, the preset sound pressure compensation algorithm includes:

[0024] Calculating the gain compensation G in the current usage environment err :

[0025] ;

[0026] where P is the air pressure of the usage environment, T is the temperature of the usage environment, P ref is the air pressure of the reference environment, T ref is the temperature of the reference environment, K is the humidity correction factor, , e is the partial pressure of water vapor, , RH is the humidity of the usage environment, e sat (T) is the saturated water vapor pressure;

[0027] The compensated output voltage value V is: , V ref is the output voltage value in the reference environment.

[0028] In some possible implementations, the formula for the main control unit to generate a pure tone signal is:

[0029]

[0030] where A ref is the amplitude of the pure tone signal in the reference environment, G err is the gain supplement in the current usage environment, f is the frequency of the pure tone signal, n is the sampling point index number of the discrete signal, f s is the sampling rate, is the initial phase.

[0031] In some possible implementations, the output amplitude of the pure tone signal output by the main control unit to the digital-to-analog converter is 0 to 224 -1. The frequency of the pure tone signal is 20 Hz to 16 kHz.

[0032] In some possible implementation manners, the amplitude of the pure tone signal is fixed at 2 by air under the reference environment 22 , and the conditions of the reference environment are: the static pressure is 101.325 kPa, the air temperature is 23 °C, and the relative humidity is 50%.

[0033] In a second aspect, a method for adjusting the frequency response of an acoustic signal generating device based on multi-sensor data acquisition is provided, which is applied to the frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition as described in the first aspect. The measurement microphone is inserted into the coupling cavity, and the output voltage values of the digital-to-analog converter at each frequency point under the reference environment are stored in a specified address in advance. The method includes:

[0034] Reading the output voltage values of the digital-to-analog converter at each frequency point under the reference environment stored in the specified address;

[0035] Setting the frequency of the output signal;

[0036] Setting the output voltage value of the digital-to-analog converter at the current frequency;

[0037] Reading the air pressure, temperature and humidity measured by the sensor unit under the current usage environment;

[0038] Calculating the gain compensation G under the current usage environment according to the air pressure, temperature and humidity err ;

[0039] Setting the amplitude of the pure tone signal to G err *A ref , where A ref is the amplitude of the pure tone signal under the reference environment.

[0040] In some possible implementation manners, storing the output voltage values of the digital-to-analog converter at each frequency point under the reference environment in the specified address includes:

[0041] S001. Setting the amplitude A of the pure tone signal under the reference environment ref ;

[0042] S002. Adjusting the frequency of the pure tone signal within the range of 20 Hz to 16 kHz;

[0043] S003. Judging whether the output sound pressure level meets the requirements according to the sound pressure level data measured by the measurement microphone;

[0044] If the judgment result is no, adjusting the voltage value output by the digital-to-analog converter, and executing step S003;

[0045] If the judgment result is yes, then it is judged whether the frequency of the pure tone signal is within the range of 20 Hz to 16 kHz. If it is within the range of 20 Hz to 16 kHz, step S004 is executed; otherwise, step S002 is executed.

[0046] S004. Store the output voltage values of the digital-to-analog converters at each frequency point.

[0047] In a third aspect, a computer-readable storage medium is provided. The computer-readable medium stores program code for a device to execute, and the program code includes steps for executing the method in any one of the implementation manners in the first aspect as described above.

[0048] The present application has the following beneficial effects:

[0049] 1. The system of the present application uses a sensor unit to collect information such as air pressure, temperature, and humidity in the usage environment, and designs a sound pressure compensation algorithm based on the information such as air pressure, temperature, and humidity to compensate the output sound pressure level relative to the reference environment, and adjusts the magnitude of the sound signal output so that the sound signal meets the requirements of a class 1 sound calibrator. At the same time, the system of the present application does not need to use expensive class 1 or LS class microphones, nor does it need to design an acquisition circuit and calculate the sound pressure level in the hardware circuit, thereby simplifying the circuit and reducing the cost at the same time, and realizing calibration of multiple frequency points and multiple sound pressure levels;

[0050] 2. The method of the present application calculates the gain compensation in the current usage environment based on information such as air pressure, temperature, and humidity, compensates the output sound pressure level relative to the reference environment, and adjusts the magnitude of the sound signal output so that the sound signal meets the requirements of a class 1 sound calibrator. Secondly, the designed frequency response adjustment method in the reference environment uses a DC voltage-controlled gain amplifier to solve the frequency response of the output signal within the range of 20 Hz to 16 kHz, so that the sound signal meets the requirements of a class 1 sound calibrator. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application.

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0053] Figure 1 It is a schematic diagram of a frequency response adjustment system of a sound signal generating device based on multi-sensor data acquisition in Embodiment 1 of the present application;

[0054] Figure 2 It is a schematic diagram of the power management unit in the frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition in Embodiment 1 of the present application;

[0055] Figure 3 It is a circuit diagram of the input protection circuit in the frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition in Embodiment 1 of the present application;

[0056] Figure 4 It is a storage area allocation diagram of the storage medium in the frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition in Embodiment 1 of the present application;

[0057] Figure 5 It is a flowchart of the frequency response adjustment method of the acoustic signal generating device based on multi-sensor data acquisition in Embodiment 2 of the present application;

[0058] Figure 6 It is a flowchart of obtaining the digital-to-analog converter output voltage values at each frequency point in the reference environment in Embodiment 2 of the present application.

[0059] Reference numerals:

[0060] 100, sensor unit; 200, main control unit; 300, digital-to-analog converter; 400, operational amplifier; 500, coupling cavity; 501, speaker; 600, power management unit; 601, power supply; 602, first DC-DC boost circuit; 603, second DC-DC boost circuit. Detailed implementation manners

[0061] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0062] Embodiment 1

[0063] As Figure 1 shown, a frequency response adjustment system of an acoustic signal generating device based on multi-sensor data acquisition involved in Embodiment 1 of the present application includes a sensor unit 100, a main control unit 200, a digital-to-analog converter 300, an operational amplifier 400, and a coupling cavity 500. In order to obtain a suitable voltage for power supply, it further includes a power management unit 600.

[0064] As Figure 2As shown, the power management unit 600 uses two 1.5V carbon batteries LR6 (No. 5) as the power supply 601 for power supply. A first DC-DC boost circuit 602 is built through a power chip to convert the input power supply 601 into 3.3V to supply power to devices such as the sensor unit 100 and the main control unit 200. A second DC-DC boost circuit 603 is built through a power chip to convert the input power supply 601 into 5V to supply power to devices such as the digital-to-analog converter and the operational amplifier 400.

[0065] As Figure 3 shown, the power management unit 600 further includes an input protection circuit. The input protection circuit includes a PMOS transistor Q1. The source of the PMOS transistor Q1 is connected to the positive electrode of the power supply 601 through a first resistor R1, a diode D1, and a fuse F1 connected in series in sequence. A second resistor R2 is connected in series between the gate and the source of the PMOS transistor Q1. The gate of the PMOS transistor Q1 is connected to the collector of an NPN transistor Q2 through a third resistor R3. The drain of the PMOS transistor Q1 is connected to the VUSB pin of the MiniUSB interface through a zener diode D2. The emitter of the NPN transistor Q2 is connected to the negative electrode of the power supply 601. The base of the NPN transistor Q2 is connected to the IO pin of the main control unit through a fourth resistor R4. The main control unit 200 is connected to a membrane switch S1 for controlling the output of the IO pin. The base of the NPN transistor Q2 is also connected to the negative electrode of the power supply 601 through a fifth resistor R5. A tantalum electrolytic capacitor C1, a ceramic capacitor C2, and a transient voltage suppression diode D3 are connected in parallel between the drain of the PMOS transistor Q1 and the negative electrode of the power supply 601. The negative electrode of the power supply 601 is grounded.

[0066] When the membrane switch is pressed at startup, the network POWER is grounded, and the level is 0, that is, the gate level of the PMOS transistor Q1 is 0, and Ugs < Ugs(th). At this time, the PMOS transistor Q1 is turned on, and the subsequent circuits (that is, the first DC-DC boost circuit 602 and the second DC-DC boost circuit 603) are powered to work normally. At the same time, the pin IO of the main control unit 200 continuously outputs a high level, causing the NPN transistor Q2 to be turned on, and continuously pulling down the gate level of the PMOS transistor Q1. At this time, it is in the startup state.

[0067] When the membrane switch is pressed again, the pin IO of the main control unit 200 outputs a low level. At this time, the NPN transistor Q2 is turned off, and the gate level of the PMOS transistor Q1 is pulled up by the resistor R2, and Ugs > Ugs(th). At this time, the PMOS transistor Q1 is turned off, and it is in the shutdown state at this time.

[0068] When the MiniUSB is connected, the 5V VUSB makes the VCC continuously maintained at 2.8V through the zener diode D2 (the regulated voltage value is 2.2V), bypassing the control of the PMOS transistor Q1 to supply power to the subsequent circuits, which is mainly used during program burning.

[0069] In the input protection circuit, a 0.25A one-time fuse F1 and a current-limiting resistor R1 are connected in series with the battery pack.

[0070] In the input protection circuit, diode D1 is a Schottky diode, which is used to prevent the reverse connection of the power supply 601. D3 is a transient voltage suppression diode, that is, a TVS tube. The decoupling capacitors are a tantalum electrolytic capacitor C1 with a rated voltage of 6.3V and a ceramic capacitor C2 with a rated voltage of 50V.

[0071] In this embodiment, the sensor unit 100 is mainly used to measure the air pressure, temperature and humidity in the usage environment when the system is in use, and transmit the measured data to the main control unit 200. The main control unit 200 compensates the magnitude of the output signal through a certain algorithm, so that the finally output sound signal meets the requirements of the "Verification Regulation of Sound Calibrators JJG 176-2022".

[0072] According to the "Verification Regulation of Sound Calibrators JJG 176-2022", the reference environmental conditions adopted by this system are:

[0073] Static pressure: 101.325 kPa;

[0074] Air temperature: 23 °C;

[0075] Relative humidity: 50%;

[0076] The relationship between air density and air pressure is: ;

[0077] Among them, is the air density, P is the air pressure, R is the specific gas constant of air, approximately 287, and T is the absolute temperature of the reference environment, which is 396.15K here.

[0078] The humidity correction factor is:

[0079] Among them, K is the humidity correction factor, P is the air pressure, e is the water vapor partial pressure, and the calculation formula of e is:

[0080] ;

[0081] Among them, RH is the humidity of the usage environment, e sat (T) is the saturated water vapor pressure, which can be calculated using the Wagner-Pruss equation.

[0082] Among the air pressure, temperature and humidity of the usage environment, its gain compensation G err is:

[0083]

[0084] Among them, P is the air pressure of the use environment, T is the temperature of the use environment, P ref is the air pressure of the reference environment, T ref is the temperature of the reference environment, and K is the humidity correction factor.

[0085] The compensated output voltage value is:

[0086]

[0087] Among them, V ref is the output voltage value under the reference environment.

[0088] The change in sound pressure level ∆SPL after compensation is: .

[0089] In this embodiment, the main control unit 200 mainly plays the following roles: 1. Obtain the air pressure, temperature, and humidity data of the use environment detected by the sensor unit 100, design a sound pressure compensation algorithm, and control the magnitude of the signal output by the digital-to-analog converter 300; 2. Generate a sine signal with a specified frequency and amplitude, output it through the digital-to-analog converter 300 and the operational amplifier 400, and then generate a sound signal in the coupling cavity 500; 3. Design a frequency response adjustment method and store the compensation parameters of each frequency point under the reference environmental conditions in the storage module of the main control unit 200; 4. Control the output of each power supply voltage of the power management unit 600 through the IO pins to save power consumption.

[0090] In this embodiment, the pure tone signal is generated by the following formula:

[0091]

[0092] Among them, A ref is the amplitude of the pure tone signal under the reference environment, G err is the gain supplement under the current use environment, f is the frequency of the pure tone signal, n is the sampling point index number of the discrete signal, f s is the sampling rate, is the initial phase.

[0093] Frequency response conditions under the reference environment:

[0094] (1). In this embodiment, the digital-to-analog converter 300 adopted is 24bit, and the main control unit 200 outputs data to the digital-to-analog converter 300 through the I2S interface. The output amplitude of the digital signal (i.e., the pure tone signal generated by the main control unit 200) is 0 to 2 24 -1. Under the reference temperature, the amplitude of the digital signal is fixed at 2 22 , while ensuring the signal-to-noise ratio of the output signal of the digital-to-analog converter 300, a gain compensation space is reserved, and the maximum gain compensation is 12dB.

[0095] (2). In this embodiment, the output frequency range is set to 20 Hz to 16 kHz. In the coupling cavity 500, due to the influence of the frequency response of the sound-emitting device, when the operational amplifier 400 outputs the same electrical signal, driving the sound-emitting device to emit a sound signal, there will be a large deviation in the sound pressure level of the generated sound signal. To solve this problem, the operational amplifier 400 uses a controllable gain amplifier as the main device, and utilizes the DAC peripheral of the main control unit 200 to output a DC voltage to adjust the amplitude of the output electrical signal.

[0096] (3) The DC voltage values for adjusting the gain of the controllable gain amplifier within the range of 20 Hz to 16 kHz are stored in the storage medium.

[0097] The storage scheme of this embodiment is as follows:

[0098] In this embodiment, the storage medium is mainly used to store the software of this system, as well as the DC voltage values for adjusting the gain of the controllable gain amplifier. The allocation of the storage area is as Figure 4 shown:

[0099] BootLoader: Used to store the boot program. This program is executed first when the device is powered on or software reset, to achieve the jump of the APP program;

[0100] Upgrade identification area: When the program file is successfully downloaded in full through the serial port and the total verification also passes, this area stores the size of the new program file. The boot program determines whether to copy the program file from the "upgrade file storage area" to the "APP running area" by judging the content of this area;

[0101] Instrument information storage area: Mainly used to store the software version number, hardware version number, and machine number of the instrument;

[0102] APP running area: All function programs of this system are stored in this area;

[0103] Upgrade file storage area: Receives the bin file transmitted through the serial port, and is used for subsequent software version upgrade and maintenance;

[0104] Correction value storage area for each frequency point: Used to store the DC voltage values set for adjusting the frequency response of this system at the reference temperature.

[0105] The digital-to-analog converter 300 (i.e., Digital-to-Analog Converter, abbreviated as DAC) uses the I2S audio interface to receive the pure tone signal generated by the main control unit 200 and convert it into an analog signal for subsequent circuit modules to process. The digital-to-analog converter 300 adopted in this system is 24-bit, with a sampling rate set at 48 kHz, using 3.3V as the reference voltage, and the output voltage range of this digital-to-analog converter 300 is 0 - 3.3V.

[0106] In this embodiment, the operational amplifier 400 uses a controllable gain amplifier, mainly for the following three purposes:

[0107] (1), Through the DC signal of the main control unit 200, control the amplitude of the output signal of the operational amplifier 400 to achieve the purpose of adjusting the frequency response of the sound signal output;

[0108] (2), Convert the single-ended signal output by the digital-to-analog converter 300 into a differential signal and output it to the speaker 501 in the coupling cavity 500;

[0109] (3), Have the function of power amplification to ensure that the speaker 501 can normally output sound signals.

[0110] In this embodiment, in order to achieve human-computer interaction, the main control unit 200 is also connected with human-computer interaction devices such as a touch screen, a display + control panel, or a display + keyboard + mouse. In order to achieve data storage, the main control unit is also configured with a storage medium. The sensor unit 100 is used to collect information such as air pressure, temperature, and humidity in the use environment, and design a sound pressure compensation algorithm based on information such as air pressure, temperature, and humidity to compensate the output sound pressure level relative to the reference environment and adjust the size of the sound signal output, so that the sound signal meets the requirements of a class 1 sound calibrator. At the same time, the system of this embodiment does not need to use expensive class 1 or LS-class microphones, nor does it need to design an acquisition circuit and calculate the sound pressure level in the hardware circuit, thus simplifying the circuit and reducing costs at the same time, and realizing the calibration of multiple frequency points and multiple sound pressure levels.

[0111] Embodiment 2

[0112] As Figure 5 shown, a method for adjusting the frequency response of a sound signal generating device based on multi-sensor data acquisition according to Embodiment 2 of this application. This method is applied to the frequency response adjustment system of a sound signal generating device based on multi-sensor data acquisition as described in the first aspect. Two preparatory works need to be done before implementing this method: 1. Insert the measurement microphone into the coupling cavity to detect the sound pressure level of the sound signal in the coupling cavity; 2. Store the output voltage values of the digital-to-analog converter at each frequency point in the reference environment to a specified address. This method includes:

[0113] S100. Read the digital-to-analog converter output voltage values of each frequency point stored at the specified address in the reference environment;

[0114] S200. Set the frequency of the output signal;

[0115] S300. Set the digital-to-analog converter output voltage value at the current frequency;

[0116] S400. Read the air pressure, temperature, and humidity measured by the sensor unit in the current usage environment;

[0117] S500. Calculate the gain compensation G in the current usage environment based on the air pressure, temperature, and humidity err ;

[0118] S600. Set the amplitude of the pure tone signal to G err *A ref , where A ref is the amplitude of the pure tone signal in the reference environment. In this embodiment, A ref takes 2 22 , that is, the amplitude of the pure tone signal needs to be set to G err *2 22 .

[0119] As Figure 6 shown, store the digital-to-analog converter output voltage values of each frequency point in the reference environment to the specified address. Among them, the following steps S001 - S004 are all executed with the frequency response adjustment system placed in the reference environment, specifically including:

[0120] S001. Set the amplitude A of the pure tone signal in the reference environment ref , in this embodiment, A ref takes 2 22 ;

[0121] S002. Adjust the frequency of the pure tone signal in the range of 20 Hz to 16 kHz;

[0122] S003. Judge whether the output sound pressure level meets the requirements according to the sound pressure level data measured by the measurement microphone. In this embodiment, if 93.75 dB ≤ the sound pressure level measured by the measurement microphone ≤ 94.25 dB, then it meets the requirements;

[0123] If the judgment result is no, then adjust the voltage value output by the digital-to-analog converter and execute step S003;

[0124] If the judgment result is yes, then judge whether the frequency of the pure tone signal is in the range of 20 Hz to 16 kHz. If it is in the range of 20 Hz to 16 kHz, then execute step S004, otherwise execute step S002;

[0125] S004. Store the output voltage values of the digital-to-analog converters for each frequency point.

[0126] It should be noted that in this embodiment, the gain compensation under the current usage environment is calculated based on information such as air pressure, temperature, humidity, etc., and the output sound pressure level relative to the reference environment is compensated to adjust the magnitude of the sound signal output so that the sound signal meets the requirements of a class 1 sound calibrator. For other specific implementation manners of the sound signal generating device frequency response adjustment method based on multi-sensor data acquisition in this embodiment, reference can be made to the specific implementation manners of the sound signal generating device frequency response adjustment system based on multi-sensor data acquisition above. To avoid redundancy, it will not be elaborated here.

[0127] Embodiment 3

[0128] A computer-readable storage medium involved in Embodiment 3 of the present application, the computer-readable medium stores program codes for a device to execute, and the program codes include steps for executing the method in any one of the implementation manners in Embodiment 1 of the present application;

[0129] Among them, the computer-readable storage medium can be a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM); the computer-readable storage medium can store program codes, and when the program stored in the computer-readable storage medium is executed by a processor, the processor is used to execute the steps of the method in any one of the implementation manners in Embodiment 1 of the present application.

[0130] The above is only the preferred specific implementation manner of the present application; however, the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application, according to the technical solution of the present application and its improved concept, makes equivalent replacements or changes, and should be covered by the protection scope of the present application.

Claims

1. A frequency response adjustment system for an acoustic signal generating device based on multi-sensor data acquisition, characterized in that, Including: A sensor unit, configured to detect the air pressure, temperature, and humidity of the usage environment and transmit them to the main control unit; A main control unit, configured to control the magnitude of the output signal of the digital-to-analog converter, generate a pure tone signal with a specified frequency and amplitude, and adjust the frequency response based on a preset sound pressure compensation algorithm according to the air pressure, temperature, and humidity of the usage environment, and store the compensation parameters of each frequency point under the reference environmental conditions; A digital-to-analog converter, configured to convert the pure tone signal generated by the main control unit into an analog signal; An operational amplifier, configured to control the amplitude of the output signal through the DC signal of the main control unit and convert the analog signal from a single-ended signal to a differential signal for output to a speaker in the coupling cavity for sound signal output; A coupling cavity, configured to convert the differential signal into a sound signal through the internal speaker.

2. The frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition according to claim 1, wherein It further includes a power management unit, and the power management unit includes a first DC-DC boost circuit and a second DC-DC boost circuit. Among them, the first DC-DC boost circuit is configured to convert the accessed power supply into a first specified voltage to supply power to the sensor unit and the main control unit, and the second DC-DC boost circuit is configured to convert the accessed power supply into a second specified voltage to supply power to the digital-to-analog converter and the operational amplifier.

3. The frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition according to claim 2, wherein The power management unit further includes an input protection circuit, and the input protection circuit includes a PMOS transistor. The source electrode of the PMOS transistor is connected to the positive electrode of the power supply through a first resistor, a diode, and a fuse connected in series in sequence. A second resistor is connected in series between the gate electrode and the source electrode of the PMOS transistor. The gate electrode of the PMOS transistor is connected to the collector of an NPN transistor through a third resistor. The drain electrode of the PMOS transistor is connected to VUSB through a zener diode. The emitter of the NPN transistor is connected to the negative electrode of the power supply. The base of the NPN transistor is connected to the IO pin of the main control unit through a fourth resistor. The main control unit is connected with a membrane switch for controlling the output of the IO pin. The base of the NPN transistor is also connected to the negative electrode of the power supply through a fifth resistor. A tantalum electrolytic capacitor, a ceramic capacitor, and a transient voltage suppression diode are connected in parallel between the drain electrode of the PMOS transistor and the negative electrode of the power supply, and the negative electrode of the power supply is grounded.

4. The frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition according to claim 1, wherein The preset sound pressure compensation algorithm includes: Calculate the gain compensation G in the current usage environment err : ； where P is the atmospheric pressure of the usage environment, T is the temperature of the usage environment, P ref is the atmospheric pressure of the reference environment, T ref is the temperature of the reference environment, K is the humidity correction factor, , e is the partial pressure of water vapor, , RH is the humidity of the usage environment, e sat (T) is the saturated water vapor pressure; The compensated output voltage value V is as follows: , V ref is the output voltage value in the reference environment.

5. The frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition according to claim 4, characterized in that, The formula for the main control unit to generate a pure tone signal is: ； Among them, A ref is the amplitude of the pure tone signal in the reference environment, G err is the gain supplement in the currently used environment, f is the frequency of the pure tone signal, n is the sampling point index number of the discrete signal, f s is the sampling rate, is the initial phase.

6. The frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition according to any one of claims 1-5, characterized in that, The output amplitude of the pure tone signal output by the master control unit is 0 to 2 24 -1, and the frequency of the pure tone signal is 20 Hz to 16 kHz.

7. The frequency response adjustment system of the acoustic signal generating device based on multi-sensor data acquisition according to claim 4 or 5, characterized in that, The air fixes the amplitude of the pure tone signal to 2 under the reference environment 22 , and the conditions of the reference environment are: static pressure is 101.325 kPa, air temperature is 23 °C, and relative humidity is 50%.

8. A method for adjusting the frequency response of an acoustic signal generating device based on multi-sensor data acquisition, characterized in that, Applied to the frequency response adjustment system of the sound signal generating device based on multi-sensor data acquisition according to any one of claims 1-7, insert a measurement microphone into the coupling cavity, and store the output voltage values of the digital-to-analog converter at each frequency point under the reference environment into a specified address in advance. The method includes: Read the output voltage values of the digital-to-analog converter at each frequency point stored in the specified address under the reference environment; Set the frequency of the output signal; Set the output voltage value of the digital-to-analog converter at the current frequency; Read the air pressure, temperature, and humidity measured by the sensor unit in the current usage environment; Calculate the gain compensation G in the current usage environment based on the air pressure, temperature, and humidity err ; Set the amplitude of the pure tone signal to G err *A ref , where A ref is the amplitude of the pure tone signal in the reference environment.

9. The method for adjusting the frequency response of the acoustic signal generating device based on multi-sensor data acquisition according to claim 8, characterized in that Storing the output voltage values of the digital-to-analog converter at each frequency point under the reference environment into the specified address includes: S001. Set the amplitude A of the pure tone signal in the reference environment ref ; S002. Adjust the frequency of the pure tone signal within the range of 20 Hz to 16 kHz; S003. Judge whether the output sound pressure level meets the requirements according to the sound pressure level data measured by the measurement microphone; If the judgment result is negative, adjust the voltage value output by the digital-to-analog converter, and execute step S003; If the judgment result is positive, determine whether the frequency of the pure tone signal is within the range of 20 Hz to 16 kHz. If it is within the range of 20 Hz to 16 kHz, execute step S004; otherwise, execute step S002; S004. Store the voltage values output by the digital-to-analog converter for each frequency point.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores program codes for device execution, and the program codes include steps for executing the method according to claim 8 or 9.

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