An electroacoustic joint calibration system and calibration method for a pulsating pressure sensor

Abstract

An electroacoustic joint calibration system and method for a pulsating pressure sensor belongs to the field of sensor calibration technology. The invention includes a cylindrical spatial sound field excitation cavity, a standard microphone, and a pulsating pressure sensor. The standard microphone and / or the pulsating pressure sensor are detachably mounted at the bottom of the cylindrical spatial sound field excitation cavity. The cylindrical spatial sound field excitation cavity includes an excitation sound source, a cylindrical sound cavity, and a locking device. The locking device fixes and locks the outer wall of the cylindrical sound cavity. The excitation sound source is located above the cylindrical sound cavity, and the standard microphone and / or the pulsating pressure sensor are detachably mounted at the bottom of the cylindrical sound cavity. This invention is an electroacoustic joint calibration method for a pulsating pressure sensor that uses spatial sound field excitation and voltage signal acquisition to calculate the transfer function. It enables the testing of the dynamic response characteristics of the pulsating pressure sensor using electroacoustic system hardware, achieving rapid calibration of the amplitude-frequency and phase-frequency characteristics of the pulsating pressure sensor.

Description

Technical Field

[0001] This invention relates to an electroacoustic combined calibration system and calibration method for a pulsating pressure sensor, belonging to the field of sensor calibration technology. Background Technology

[0002] When an aircraft moves at varying speeds in a high-speed airflow, the high-speed airflow near the fuselage continuously changes and forms different flow field distributions. This creates flow field phenomena such as airflow separation, turbulence, shock waves, and boundary layer interference on the fuselage surface, generating strong pulsating pressure. This further excites continuous structural vibration and noise, leading to severe deterioration or even failure of the aircraft's internal electronic instrument and equipment systems. The coupling effect of prolonged or intense pulsating pressure with vibration and noise can cause fatigue and tearing of the fuselage structure, thereby posing a threat to the safety of aircraft operation and even potentially causing flight accidents. This is a serious threat to the safety of aircraft operation.

[0003] With the continuous development of my country's aviation technology in both military and civilian applications, there is an urgent need for aircraft development to test the pulsating pressure level of aircraft through experimental means, determine the pulsating pressure distribution on the airframe surface, and provide input for airframe fatigue analysis to support aircraft design optimization and load control. Directly testing pulsating pressure through wind tunnel testing or flight testing is an indispensable analytical method in the process of aircraft development.

[0004] Since the 1960s, the international aerospace field has conducted extensive research on aircraft pulse pressure testing. Currently, obtaining test data using piezoelectric pulse pressure sensors is the most direct and effective testing method for pulse pressure testing. To ensure the effectiveness of the test and the accuracy and reliability of the test data, it is necessary to periodically calibrate the pulse pressure sensor and trace its output response to a specific benchmark before it can be used for testing. Calibration of pulse pressure sensors can be divided into two categories: dynamic characteristic calibration and static characteristic calibration. The most crucial indicator is the dynamic response sensitivity of the pulse pressure sensor, specifically the calibration of its amplitude-frequency and phase-frequency characteristics. This can be achieved by exciting a sound pressure field at the input of the pulse pressure sensor and acquiring the voltage signal at its output, thus testing and calibrating the piezoelectric characteristics of the piezoelectric pulse pressure sensor. Since sound pressure is a low-amplitude, weak pulse pressure, using sound pressure, compared to traditional gas-source-based calibration methods, offers simpler and more efficient calibration equipment. It can accurately calibrate the physical-electrical input-output relationship of the pulse pressure sensor, significantly improving the reliability of the test data and having significant application value for the effective conduct of aircraft pulse pressure testing research. However, existing sound pressure-based calibration methods still lack a standardized and efficient electroacoustic joint excitation and acquisition analysis process in terms of how to efficiently and systematically excite sensors and accurately calculate their complete dynamic transfer function.

[0005] Therefore, there is an urgent need to propose an electroacoustic joint calibration system and calibration method for pulsating pressure sensors to solve the above-mentioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to propose an electroacoustic joint calibration system and method for pulsating pressure sensors. This method involves spatial sound field excitation, acquisition of voltage signals, and calculation of the transfer function of the pulsating pressure sensor. It enables the testing of the dynamic response characteristics of the pulsating pressure sensor using electroacoustic system hardware, achieving rapid calibration of the amplitude-frequency and phase-frequency characteristics of the pulsating pressure sensor. A brief overview of the invention is provided below to offer a basic understanding of certain aspects of the invention. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention.

[0007] The technical solution of the present invention:

[0008] Option 1: An electroacoustic joint calibration system for a pulsating pressure sensor, comprising a cylindrical spatial sound field excitation cavity, a standard microphone, and a pulsating pressure sensor. The standard microphone and / or the pulsating pressure sensor are detachably installed at the bottom of the cylindrical spatial sound field excitation cavity. The cylindrical spatial sound field excitation cavity includes an excitation sound source, a cylindrical sound cavity, and a locking device. The locking device fixes and locks the outer wall of the cylindrical sound cavity. An excitation sound source is provided above the cylindrical sound cavity. The standard microphone and / or the pulsating pressure sensor are detachably installed at the bottom of the cylindrical sound cavity.

[0009] Option 2: An electroacoustic joint calibration method for a pulsating pressure sensor, based on the electroacoustic joint calibration system for a pulsating pressure sensor described in Option 1, includes the following steps:

[0010] Step 1: Excite the spatial calibration sound field;

[0011] Connect the excitation sound source and the cylindrical acoustic cavity, and use a locking device to fix their relative positions;

[0012] Step 2: Spatial sound field correlation calibration;

[0013] Two standard microphones are installed at symmetrical positions at the bottom of the cylindrical acoustic cavity. and standard microphone The sound source is excited to radiate a broadband white noise sound field, and the sound pressure of the sound field at the measurement point of the standard microphone is collected. The correlation coefficient of the two standard microphones is compared to see if it is greater than 0.95. If not, the placement conditions of the two standard microphones are optimized and the above steps are repeated until the correlation coefficient of the two standard microphones is greater than 0.95, and then step three is performed.

[0014] Step 3: Single-frequency response analysis of the pulsating pressure sensor;

[0015] Replace one of the standard microphones with a pulsating pressure sensor, obtain the sound pressure signal of the remaining standard microphone and the sound pressure signal of the pulsating pressure sensor, calibrate the excitation sound source to radiate a single-frequency signal, and calculate the single-frequency sensitivity of the pulsating pressure sensor.

[0016] Step 4: Calculation of the transfer function of the pulsating pressure sensor;

[0017] The broadband white noise radiated from the sound source was calibrated, and the transfer function of the pulsating pressure sensor was calculated.

[0018] Preferably, step one includes: forming a spatial sound field for calibrating the sensor through a cylindrical spatial sound field excitation cavity, driving the excitation sound source to radiate broadband white noise, and forming a spatial sound field symmetrical about the center in the radial direction inside the cylindrical sound cavity.

[0019] Preferably, the opening position in step two is at a position symmetrical about the radius of the center at the bottom of the cylindrical acoustic cavity;

[0020] The standard microphone is a standard microphone with known sensitivity.

[0021] The optimization of the placement conditions of the two standard microphones involves optimizing the opening position or adjusting the installation method of the excitation sound source while ensuring that there is a spatial sound field that meets the calibration accuracy requirements.

[0022] Preferably, step three, calculating the single-frequency sensitivity of the pulsating pressure sensor, includes: calculating the single-frequency signal sound pressure at the spatial location of the measuring point with two openings based on the sensitivity of a standard microphone, and calculating the static sensitivity of the pulsating pressure sensor at this frequency point based on the sensor comparison calibration principle.

[0023] Preferably, step four includes: driving the excitation sound source to radiate broadband white noise; measuring the open-circuit output voltage of a standard microphone and a pulsating pressure sensor under conditions of sufficient signal-to-noise ratio; calculating the actual broadband pulsating pressure signal based on the sensitivity of the standard microphone; and calculating the dynamic response sensitivity test result of the pulsating pressure sensor using the broadband pressure signal, the open-circuit output voltage of the pulsating pressure sensor, and its static sensitivity, and further obtaining the amplitude-frequency response characteristics and phase-frequency characteristics of the pulsating pressure sensor.

[0024] The present invention has the following beneficial effects:

[0025] This invention calibrates the dynamic response characteristics of a pulsating pressure sensor by employing spatial acoustic field excitation and calculating the transfer function from acquired voltage signals. This enables rapid calibration of the amplitude-frequency and phase-frequency characteristics of the pulsating pressure sensor. Compared to traditional gas-source-based calibration methods for pulsating pressure sensors, this method achieves high-precision calibration quickly and effectively, avoiding the need for complex gas-source calibration equipment. This is of great significance for improving the applicability of pulsating pressure sensors and enhancing the reliability and validity of pulsating pressure testing data. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of an electroacoustic joint calibration system for a pulsating pressure sensor;

[0027] Figure 2 This is a flowchart of an electroacoustic joint calibration method for a pulsating pressure sensor.

[0028] In the diagram: 1-Standard microphone, 2-Pulsating pressure sensor, 3-Excitation sound source, 4-Cylindrical acoustic cavity, 5-Locking device. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0030] The connections mentioned in this invention are divided into fixed connections and detachable connections. Fixed connections (i.e., non-detachable connections) include, but are not limited to, conventional fixed connection methods such as folded connections, riveted connections, adhesive connections, and welded connections. Detachable connections include, but are not limited to, conventional disassembly methods such as threaded connections, snap-fit ​​connections, pin connections, and hinged connections. When a specific connection method is not explicitly defined, it is assumed that at least one existing connection method can always be found to achieve the function, and those skilled in the art can choose according to their needs. For example, a welded connection can be chosen for fixed connections, and a hinged connection can be chosen for detachable connections.

[0031] Specific implementation method one: Combining Figure 1This embodiment describes an electroacoustic joint calibration system for a pulsating pressure sensor, comprising a cylindrical spatial sound field excitation cavity, a standard microphone 1, and a pulsating pressure sensor 2. The standard microphone 1 and / or the pulsating pressure sensor 2 are detachably mounted at the bottom of the cylindrical spatial sound field excitation cavity. The cylindrical spatial sound field excitation cavity includes an excitation sound source 3, a cylindrical sound cavity 4, and a locking device 5. The locking device 5 fixes and locks the outer wall of the cylindrical sound cavity 4. The excitation sound source 3 is located above the cylindrical sound cavity 4, and the standard microphone 1 and / or the pulsating pressure sensor 2 are detachably mounted at the bottom of the cylindrical sound cavity 4. The excitation sound source 3 is used to excite the spatial calibration sound pressure field, calibrate the spatial sound field correlation, test the single-frequency response of the pulsating pressure sensor 2, and calculate the broadband transfer function, amplitude frequency response characteristics, and phase frequency response characteristics of the pulsating pressure sensor 2.

[0032] The excitation sound source 3 is a standard sound source with a circular radiating surface, and its effective sound emission frequency is 50Hz-20kHz, which covers the test frequency of the pulsating pressure sensor 2 to be calibrated.

[0033] The cylindrical acoustic cavity 4 is a straight hollow cylindrical structure with a closed lower surface. The circular area is the same as the radiation area of ​​the excitation sound source 3, ensuring that after the cylindrical acoustic cavity 4 and the excitation sound source 3 are combined, a spatial sound field that is symmetrical about the center in the radial direction can be formed inside the closed space.

[0034] The locking device 5 is used to fix the excitation sound source 3 and the cylindrical acoustic cavity 4, so that the two are coaxial and avoid relative positional movement, which would affect the spatial symmetry of the calibration sound field.

[0035] Specific Implementation Method Two: Combining Figures 1-2 This embodiment describes an electroacoustic joint calibration method for a pulsating pressure sensor, which is based on the electroacoustic joint calibration system for a pulsating pressure sensor described in Specific Embodiment 1, and includes the following steps:

[0036] Step 1: Excite the spatial calibration sound field;

[0037] The excitation sound source 3 and the cylindrical acoustic cavity 4 are connected, and the locking device 5 fixes their relative positions.

[0038] Step 2: Spatial sound field correlation calibration;

[0039] The cylindrical acoustic cavity 4 has symmetrical openings at its bottom to install two standard microphones 1, i.e., standard microphones. and standard microphone The sound source is excited to radiate a broadband white noise sound field, and the sound pressure of the sound field at the measuring point of standard microphone 1 is collected. The correlation coefficient of the two standard microphones 1 is compared to see if it is greater than 0.95. If not, the placement conditions of the two standard microphones 1 are optimized, and the above steps are repeated until the correlation coefficient of the two standard microphones 1 is greater than 0.95, and then step three is performed.

[0040] Step 3: Single-frequency response analysis of the pulsating pressure sensor;

[0041] Replace one of the standard microphones 1 with a pulsating pressure sensor 2, obtain the sound pressure signal of the remaining standard microphone 1 and the sound pressure signal of the pulsating pressure sensor 2, calibrate the excitation sound source 3 to radiate a single-frequency signal, and calculate the single-frequency sensitivity of the pulsating pressure sensor 2.

[0042] Step 4: Calculation of the transfer function of the pulsating pressure sensor;

[0043] The broadband white noise radiated by the sound source was calibrated, and the transfer function of the pulsating pressure sensor 2 was calculated.

[0044] Step one includes: forming a spatial sound field for calibrating the sensor through a cylindrical spatial sound field excitation cavity, driving the excitation sound source 3 to radiate broadband white noise, forming a spatial sound field symmetrical about the center in the radial direction inside the cylindrical sound cavity 4, and calibrating the output characteristics of the pulsating pressure sensor 2 by measuring the pressure pulsation at the symmetrical position.

[0045] The opening position in step two is at a position symmetrical about the center radius at the bottom of the cylindrical acoustic cavity 4.

[0046] The standard microphone 1 is a standard microphone 1 with known sensitivity;

[0047] The optimization of the placement conditions of the two standard microphones 1 is to optimize the opening position or adjust the installation method of the excitation sound source 3 under the condition of ensuring that there is a spatial sound field that meets the calibration accuracy requirements.

[0048] The calculation of the single-frequency sensitivity of the pulsating pressure sensor 2 in step three includes: calculating the single-frequency signal sound pressure at the spatial location of the measuring point of the two openings based on the sensitivity of the standard microphone 1, and calculating the static sensitivity of the pulsating pressure sensor 2 at this frequency point based on the sensor comparison calibration principle.

[0049] Step four includes: driving the excitation sound source 3 to radiate broadband white noise; measuring the open-circuit output voltage of the standard microphone 1 and the pulsating pressure sensor 2 under conditions of sufficient signal-to-noise ratio; calculating the actual broadband pulsating pressure signal based on the sensitivity of the standard microphone 1; and calculating the dynamic response sensitivity test result of the pulsating pressure sensor 2 using the broadband pressure signal, the open-circuit output voltage of the pulsating pressure sensor, and its static sensitivity, and further obtaining the amplitude-frequency response characteristics and phase-frequency characteristics of the pulsating pressure sensor 2.

[0050] Specific implementation method three: Combining Figures 1-2This embodiment, based on Specific Embodiment 1, describes an electroacoustic joint calibration method for a pulsating pressure sensor. It relies on the electroacoustic joint calibration system for a pulsating pressure sensor described in Specific Embodiment 1 and includes the following steps:

[0051] Step 1: Excite the spatial calibration sound field;

[0052] The excitation sound source 3 and the cylindrical acoustic cavity 4 are connected, and the locking device 5 fixes their relative positions.

[0053] Step 2: Spatial sound field correlation calibration;

[0054] The cylindrical acoustic cavity 4 has symmetrical openings at its bottom, where two standard microphones 1 are installed. and standard microphone A broadband white noise signal is generated using a signal generation program and signal generation card designed based on the LabVIEW platform. This signal excites the spatial sound field inside the acoustic cavity, and the sound source radiates the broadband white noise sound field. The sound pressure of the sound field at the measuring point of standard microphone 1 is collected. The correlation coefficient between the two standard microphones 1 is compared to see if it is greater than 0.95. If not, the placement conditions of the two standard microphones 1 are optimized, and the above steps are repeated until the correlation coefficient between the two standard microphones 1 is greater than 0.95. Then, step three is performed.

[0055] Acquiring standard microphone data via a high-speed dynamic signal acquisition card. Open-circuit output voltage and standard microphone Open-circuit output voltage According to the sound pressure sensitivity calculation formula:

[0056]

[0057] in, The output voltage at the open-circuit terminal of the microphone. This is broadband white noise data. Under the test conditions of this system, based on a standard microphone... Sensitivity and standard microphone Sensitivity The broadband white noise data collected by the two standard microphones were calculated. and Calculate the collected sample sequence Point-wise discrete Fourier transform converts the time-domain signal to the frequency domain, obtaining the frequency domain result of the test signal. and As shown in the following formula:

[0058]

[0059] in, express The index of the signal spectrum function after point discrete Fourier transform. It is the natural logarithm. The imaginary unit is 'i', where 'i' represents the sequence number of the time signal, based on the signal frequency domain. and Calculate its sound pressure level and The calculation formula is: For microphones used in the air, For reference sound pressure level, The value is Pa, The effective value of the measured sound pressure. This represents the calculated sound pressure level.

[0060] Calculate the signal correlation coefficient to determine the standard microphone. With standard microphone The correlation coefficient of the received sound pressure signal at the spatial location is calculated using the following formula:

[0061]

[0062] in, This represents the covariance of two signal sequences. They represent and The variance of the standard microphone is calculated using the correlation coefficient formula. Data collection results With standard microphone Data collection results correlation coefficient The result value is in Within a certain range, it indicates a strong correlation between the two signals;

[0063] Set the error threshold to ,Compare , absolute error And the error threshold size. Set the correlation threshold to... ,Compare , correlation coefficient And the magnitude of the correlation threshold, if , If the surface sound field of the calibration model meets the calibration requirements, then optimize the sound field placement conditions until the sound pressure level error and correlation of the test sound field meet the threshold conditions.

[0064] Step 3: Single-frequency response analysis of the pulsating pressure sensor;

[0065] Replace one of the standard microphones 1 with a pulsating pressure sensor 2, obtain the sound pressure signal of the remaining standard microphone 1 and the sound pressure signal of the pulsating pressure sensor 2, calibrate the excitation sound source 3 to radiate a single-frequency signal, and calculate the single-frequency sensitivity of the pulsating pressure sensor 2.

[0066] Keeping the cylindrical acoustic cavity 4 connected to the excitation sound source 3 unchanged, after spatial sound field calibration, at the measurement point location with the same spatial sound field characteristics, the pulsating pressure sensor 2 to be calibrated is used. Replace with a standard microphone At the location, a 1000Hz single-frequency signal is generated through a signal generation program, which excites a single-frequency spatial sound field within a cylindrical spatial sound field excitation cavity, and the pulsating pressure sensor collects the data. Open-circuit output voltage and standard microphone Open-circuit output voltage At this point, both microphones have the same pressure field conditions at a frequency of 1000Hz. , The sound pressure level at the measuring point of standard microphone 1. To determine the sound pressure value at the measuring point of the pulsating pressure sensor 2 to be calibrated, the calibration principle of the sensor sensitivity comparison method is used to calculate the sound pressure value of the pulsating pressure sensor. Sound pressure sensitivity at 1000Hz:

[0067]

[0068] in The value represents the sound pressure sensitivity of the pulsating pressure sensor to be calibrated at 1000Hz. For standard microphones Sound pressure sensitivity at 1000 Hz.

[0069] Step 4: Calculation of the transfer function of the pulsating pressure sensor;

[0070] The broadband white noise radiated by the sound source was calibrated, and the transfer function of the pulsating pressure sensor 2 was calculated.

[0071] Keeping the cylindrical acoustic cavity 4 connected to the excitation sound source 3 unchanged, a broadband white noise signal is generated through a signal generation program, which excites a broadband spatial sound field within the cylindrical acoustic field excitation cavity. The pulsating pressure sensor 2 is considered as a complete piezoelectric response system, with its input being the pressure at the measuring point of the pulsating pressure sensor 2 and its output being the output voltage of the pulsating pressure sensor 2. Based on the input-output relationship of the sensor system, the transfer function is calculated to obtain the amplitude-frequency and phase-frequency characteristics of the dynamic response of the pulsating pressure sensor 2.

[0072] Set a standard microphone The sound pressure signal received at the location is Pulsating pressure sensor The measured output voltage is The sound pressure sensitivity at 1000Hz was measured using the pulsating pressure sensor to be calibrated. The calculated acoustic signal is The sound signal is the same as the actual sound signal at the measuring point. The differences exist; the values ​​are determined by the dynamic response characteristics of the pulsating pressure sensor 2, and the relationship can be established through a transfer function.

[0073]

[0074] Where * denotes linear convolution. express and The impulse response function between the two is determined by the piezoelectric characteristics of the pulsating pressure sensor. According to the definition of the transfer function, the sound pressure signal... , Performing a Fourier transform yields:

[0075]

[0076] in , Representing real sound signals respectively With output sound signal The Fourier transform yields It is an impulse response function The Fourier transform of the system, i.e., the frequency response function of the system, is usually a complex number:

[0077]

[0078] in For the system's amplitude-frequency response characteristics, The system's phase frequency response characteristics are represented by the amplitude frequency response function. By correcting the measured signal, the true pressure signal result can be obtained.

[0079] After the above steps, the dynamic response characteristics of the pulsating pressure sensor 2 under broadband white noise excitation are measured, including the system amplitude frequency response characteristics and phase frequency response characteristics, and the single-frequency static sensitivity at 1000Hz, thus completing the electroacoustic joint calibration of the pulsating pressure sensor.

[0080] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0081] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electroacoustic joint calibration system for a pulsating pressure sensor, characterized by: The utility model relates to a kind of standard microphone and pulsating pressure sensor calibration device, including cylindrical space sound field excitation cavity, standard microphone (1) and pulsating pressure sensor (2), standard microphone (1) and / or pulsating pressure sensor (2) are detachably installed in the bottom of cylindrical space sound field excitation cavity, the cylindrical space sound field excitation cavity includes excitation sound source (3), cylindrical acoustic cavity (4) and locking device (5), locking device (5) is fixed and locked cylindrical acoustic cavity (4) outer wall, excitation sound source (3) is equipped above cylindrical acoustic cavity (4), standard microphone (1) and / or pulsating pressure sensor (2) are detachably installed in the bottom of cylindrical acoustic cavity (4).

2. The method of electroacoustic combined calibration of a pulsating pressure sensor, relying on the electroacoustic combined calibration system of a pulsating pressure sensor according to claim 1, characterized in that, It includes the following steps: Step one: excite space calibration sound field; Connect excitation sound source (3) and cylindrical acoustic cavity (4), locking device (5) fixes relative position; Step two: space sound field correlation calibration; Two standard microphones (1) are installed at the symmetrical position of the bottom of the cylindrical acoustic cavity (4), namely standard microphone and standard microphone A broadband white noise sound field is radiated by an excitation sound source, and the sound pressure of the sound field at the measurement point of the standard microphone (1) is collected. If the correlation coefficient of the two standard microphones (1) is not greater than 0.95, the placement conditions of the two standard microphones (1) are optimized, and the above steps are repeated until the correlation coefficient of the two standard microphones (1) is greater than 0.95, and then step three is performed. Step three: pulsating pressure sensor single-frequency response analysis; Replace one of standard microphone (1) with pulsating pressure sensor (2), obtain the sound pressure signal of the remaining standard microphone (1) and the sound pressure signal of pulsating pressure sensor (2), calibrate the single-frequency signal radiated by excitation sound source (3), and calculate the single-frequency sensitivity of pulsating pressure sensor (2); Step four: pulsating pressure sensor transfer function calculation; Calibrate the broadband white noise radiated by the sound source, and calculate the transfer function of pulsating pressure sensor (2).

3. The electroacoustic combined calibration method of a pulsating pressure sensor according to claim 2, characterized in that: The step one includes forming a space sound field for calibrating sensors through the cylindrical space sound field excitation cavity, driving excitation sound source (3) to radiate broadband white noise, and forming a space sound field symmetrical about the center in the radial direction inside the cylindrical acoustic cavity (4).

4. The electroacoustic combined calibration method of a pulsating pressure sensor according to claim 3, characterized in that: The opening position of the step two is at the radially symmetrical position about the center of the bottom of the cylindrical acoustic cavity (4). The standard microphone (1) is a standard microphone (1) with known sensitivity. The optimization of the placement conditions of the two standard microphones (1) is to optimize the opening position or adjust the installation mode of excitation sound source (3) under the condition of ensuring that the space sound field meets the calibration accuracy requirements.

5. The electroacoustic combined calibration method of a pulsating pressure sensor according to claim 4, characterized in that: The calculation of the single-frequency sensitivity of pulsating pressure sensor (2) in the step three includes calculating the single-frequency sound pressure at the space positions of the two openings according to the sensitivity of the standard microphone (1), and calculating the static sensitivity of pulsating pressure sensor (2) at this frequency point according to the sensor comparison calibration principle.

6. The electroacoustic combined calibration method of a pulsating pressure sensor according to claim 5, characterized in that: The step four includes driving excitation sound source (3) to radiate broadband white noise, measuring the open-end output voltage of standard microphone (1) and pulsating pressure sensor (2) under the condition of having sufficient signal-to-noise ratio, calculating the actual broadband pulsating pressure signal according to the sensitivity of standard microphone (1), calculating the dynamic response sensitivity test result of pulsating pressure sensor (2) through the broadband pressure signal, the open-end output voltage of pulsating pressure sensor and its static sensitivity, and further obtaining the amplitude-frequency response characteristic and phase-frequency characteristic of pulsating pressure sensor (2).

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