Circular harmonic domain calibration method, device and system for annular microphone array

Abstract

The present invention discloses a circular harmonic domain calibration method, device and system for an annular microphone array. The circular harmonic domain calibration method of the present invention comprises collecting sampling signals of the annular microphone array rotating under a sound source, wherein one rotation comprises D rotation angles, each rotation angle comprises N sampling points, and each sampling point corresponds to multiple single-frequency signal frequencies; converting the sampling signals into frequency domain data; selecting one frequency domain data as a reference, calculating the relative transfer function between the frequency domain data and constructing a transfer function matrix H. D ; According to the transfer function matrix H D The circular harmonic calibration parameter E is calculated. The present invention can achieve circular harmonic calibration of the annular microphone array, so that the annular microphone array can achieve directional sound reception more accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of microphone array element calibration, and in particular to a circular harmonic domain calibration method and device for an annular microphone array. Background Art

[0002] In recent years, research on outdoor noise monitoring has developed significantly as environmental noise pollution has become increasingly serious. During outdoor monitoring, the target sound source is often a steady-state broadband sound source with a fixed incident direction, while the interfering sound source is often transient ambient noise with an unfixed incident direction. Common outdoor sound sources are often a superposition of multiple sound sources. When measuring the sound pressure level of a target noise source outdoors, a single microphone cannot suppress the interference of other noises, which greatly affects the accuracy of the microphone test results. Therefore, it is necessary to adopt microphone array-based technology for directional sound reception, and circular harmonic domain directional sound reception is widely used due to its equal beamwidth characteristics. However, due to limitations such as the installation location, the microphone received signal does not fully meet the requirements of circular harmonic domain technology. Therefore, how to pre-calibrate the microphone array has become a key technical issue that needs to be solved urgently. Summary of the Invention

[0003] The technical problem to be solved by the present invention is as follows: In response to the above-mentioned problems in the prior art, a method, device and system for circular harmonic range calibration of an annular microphone array are provided. The present invention can realize circular harmonic range calibration of an annular microphone array, so that the annular microphone array can more accurately achieve directional sound reception.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A circular harmonic domain calibration method for an annular microphone array, comprising:

[0006] S1, collects the sampling signal of the ring microphone array rotating under the sound source;

[0007] S2, converts the sampled signal into frequency domain data;

[0008] S3, select a frequency domain data as a benchmark, calculate the relative transfer function between frequency domain data and construct the transfer function matrix H D ;

[0009] S4, according to the transfer function matrix H D The circular harmonic domain calibration parameter E is calculated.

[0010] Optionally, the annular microphone array rotates one circle under the sound source, including D rotation angles, each rotation angle includes N sampling points, each sampling point corresponds to multiple single-frequency signal frequencies, and N sampling points refers to 10*f s sampling points, where f sis the sampling frequency of the sampled signal.

[0011] Optionally, converting the sampled signal into frequency domain data in step S2 means maintaining the sampled signal in groups of single-frequency signal frequency ω, rotation angle d, and microphone m through discrete Fourier transform, converting the sampled signals of N sampling points into a set of frequency domain data, and the function expression is:

[0012]

[0013] In the above formula, T(ω,m,d) is the frequency domain data of N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, t(ω,d,m,n) is the sampling signal corresponding to the single-frequency signal frequency ω, the rotation angle d, the sampling point n, and the microphone serial number m, j is an imaginary unit, and e is a natural constant.

[0014] Optionally, the function expression for calculating the relative transfer function between frequency domain data in step S3 is:

[0015] H(ω,m,d)=T(ω,m,d) / T0,

[0016] In the above formula, H(ω,m,d) is the relative transfer function of the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone m relative to the benchmark, T(ω,m,d) is the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, and T0 is the frequency domain data used as the benchmark.

[0017] Optionally, the frequency domain data used as a reference is frequency domain data of N sampling signals corresponding to a rotation angle d of 0 and a microphone serial number m of 0 under the same single-frequency signal frequency ω.

[0018] Optionally, in step S3, a transfer function matrix H is constructed D When the transfer function matrix H D It is composed of a relative transfer function of L1*L2 dimensions, where L1 represents the total number of microphones in the annular microphone array, L2 represents the total number of rotation angles of one rotation, and L2=360 / d, where d is the rotation angle.

[0019] Optionally, the calculation function expression of the circular harmonic domain calibration parameter E in step S4 is:

[0020]

[0021] In the above formula, C D is the ideal circular harmonic coefficient, W D is a weighted diagonal matrix, H D is the transfer function matrix, β is the regularization factor, I sis the identity matrix, the superscript T represents the transpose of the matrix, and the superscript H represents the conjugate transpose of the matrix.

[0022] In addition, the present invention also provides a circular harmonic domain calibration system for an annular microphone array, comprising:

[0023] A signal sampling program unit, used for collecting sampling signals of the annular microphone array rotating under the sound source;

[0024] A frequency domain conversion program unit, used for converting the sampled signal into frequency domain data;

[0025] The transfer function calculation program unit is used to select a frequency domain data as a benchmark, calculate the relative transfer function between the frequency domain data and construct the transfer function matrix H D ;

[0026] The calibration parameter calculation program unit is used to calculate the calibration parameter according to the transfer function matrix H D The circular harmonic domain calibration parameter E is calculated.

[0027] Optionally, the annular microphone array rotates one circle under the sound source, including D rotation angles, each rotation angle includes N sampling points, each sampling point corresponds to multiple single-frequency signal frequencies, and N sampling points refers to 10*f s sampling points, where f s is the sampling frequency of the sampled signal.

[0028] Optionally, the frequency domain conversion program unit converts the sampled signal into frequency domain data by:

[0029] The sampling signal is kept in the single-frequency signal frequency ω, rotation angle d, and microphone m group by discrete Fourier transform, and the sampling signal of N sampling points is converted into a set of frequency domain data, and the function expression is:

[0030]

[0031] In the above formula, T(ω,m,d) is the frequency domain data of N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, t(ω,d,m,n) is the sampling signal corresponding to the single-frequency signal frequency ω, the rotation angle d, the sampling point n, and the microphone serial number m, j is an imaginary unit, and e is a natural constant.

[0032] Optionally, the transfer function calculation program unit calculates a function expression of the relative transfer function between frequency domain data as follows:

[0033] H(ω,m,d)=T(ω,m,d) / T0,

[0034] In the above formula, H(ω,m,d) is the relative transfer function of the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone m relative to the benchmark, T(ω,m,d) is the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, and T0 is the frequency domain data used as the benchmark.

[0035] Optionally, the frequency domain data used as a reference is frequency domain data of N sampling signals corresponding to a rotation angle d of 0 and a microphone serial number m of 0 under the same single-frequency signal frequency ω.

[0036] Optionally, the transfer function calculation program unit constructs a transfer function matrix H D When the transfer function matrix H D It is composed of a relative transfer function of L1*L2 dimensions, where L1 represents the total number of microphones in the annular microphone array, L2 represents the total number of rotation angles of one rotation, and L2=360 / d, where d is the rotation angle.

[0037] Optionally, the calibration parameter calculation program unit calculates the circular harmonic domain calibration parameter E using the following function expression:

[0038]

[0039] In the above formula, C D is the ideal circular harmonic coefficient, W D is a weighted diagonal matrix, H D is the transfer function matrix, β is the regularization factor, I s is the identity matrix, the superscript T represents the transpose of the matrix, and the superscript H represents the conjugate transpose of the matrix.

[0040] In addition, the present invention also provides a circular harmonic domain calibration device for an annular microphone array, comprising an electric turntable, a frequency-controllable sound source, a sound collection module and a central processing unit. The electric turntable is used to mount the annular microphone array to be calibrated, and the control ends of the electric turntable and the frequency-controllable sound source are respectively connected to the central processing unit. The output end of the annular microphone array is used to be connected to the central processing unit through the sound collection module. The central processing unit is programmed or configured to execute the circular harmonic domain calibration method of the annular microphone array.

[0041] In addition, the present invention also provides a circular harmonic range calibration device for an annular microphone array, comprising a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to execute the circular harmonic range calibration method for the annular microphone array.

[0042] In addition, the present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program is used to be programmed or configured by a microprocessor to execute the circular harmonic domain calibration method of the annular microphone array.

[0043] Compared with the prior art, the present invention has the following advantages: the present invention includes collecting sampling signals of a circular microphone array rotating under a sound source; converting the sampling signals into frequency domain data; selecting one frequency domain data as a reference, calculating the relative transfer function between the frequency domain data and constructing a transfer function matrix H D ; According to the transfer function matrix H D The circular harmonic calibration parameter E is calculated, and the present invention can achieve circular harmonic calibration of the annular microphone array, so that the annular microphone array can achieve directional sound reception more accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 Schematic diagram of directional sound reception application of a ring microphone array in an embodiment of the present invention.

[0045] Figure 2 Schematic diagram of the basic process of the method of the embodiment of the present invention.

[0046] Figure 3 1 and 2 are the beam patterns of the annular microphone array before and after calibration in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] During outdoor monitoring, there are usually multiple noise sources emitting sound at the same time, such as Figure 1 As shown, S1, S2 and S p For three different noise sources, a conventional single microphone cannot monitor specific outdoor noise sources in a targeted manner, meaning it cannot distinguish the noise pollution from each source. However, a circular microphone array consisting of M microphones (numbered 1, 2, 3, ..., i, ..., M) can achieve equal-beam directional sound reception. Figure 1 In a circular microphone array, the angle between adjacent microphones is α, the microphone radius is r, the angle between microphone 1 and noise source S1 is θ1, and the distance between adjacent microphones is l. However, due to limitations in manufacturing and installation errors of the circular microphone array, its actual directional beam differs significantly from the ideal directional beam, so it is necessary to calibrate the circular microphone array in advance.

[0048] like Figure 2 As shown, the circular harmonic domain calibration method of the annular microphone array in this embodiment includes:

[0049] S1, collects the sampling signal of the ring microphone array rotating under the sound source;

[0050] S2, converts the sampled signal into frequency domain data;

[0051] S3, select a frequency domain data as a benchmark, calculate the relative transfer function between frequency domain data and construct the transfer function matrix H D ;

[0052] S4, according to the transfer function matrix H D The circular harmonic domain calibration parameter E is calculated.

[0053] In step S1 of this embodiment, the annular microphone array rotates one circle under the sound source, including D rotation angles. Each rotation angle includes N sampling points, and each sampling point corresponds to multiple single-frequency signals. To ensure the accuracy of the test data, the measurement time for each frequency point is 10s, so N sampling points refers to 10*f s sampling points, where f s is the sampling frequency of the sampled signal. In step S1 of this embodiment, one rotation includes 72 rotation angles, so the rotation angle is 5°.

[0054] To collect sampling signals from the rotating ring microphone array under a sound source, step S1 begins by rotating the turntable to the 0-degree position. The transmitting sound source then transmits a single-frequency signal, ω, from 100 Hz to 8000 Hz in 50-Hz intervals for 10 seconds. The corresponding sampling signal, t(ω, d, m, n), is recorded for each microphone array element. Here, d represents the rotation angle, n represents the sampling point, and m represents the microphone number. The turntable then rotates in 5-degree increments until a full rotation is completed. Calibration signals are recorded for each angle.

[0055] In this embodiment, converting the sampled signal into frequency domain data in step S2 means maintaining the sampled signal in groups of single-frequency signal frequency ω, rotation angle d, and microphone m through discrete Fourier transform, converting the sampled signals of N sampling points into a set of frequency domain data, and the function expression is:

[0056]

[0057] In the above formula, T(ω,m,d) is the frequency domain data of N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, t(ω,d,m,n) is the sampling signal corresponding to the single-frequency signal frequency ω, the rotation angle d, the sampling point n, and the microphone serial number m, j is an imaginary unit, and e is a natural constant.

[0058] In this embodiment, the function expression for calculating the relative transfer function between frequency domain data in step S3 is:

[0059] H(ω,m,d)=T(ω,m,d) / T0,

[0060] In the above formula, H(ω,m,d) is the relative transfer function of the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone m relative to the benchmark, T(ω,m,d) is the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, and T0 is the frequency domain data used as the benchmark.

[0061] In this embodiment, the frequency domain data used as a reference is the frequency domain data of N sampling signals corresponding to the rotation angle d being 0 and the microphone number m being 0 under the same single frequency signal frequency ω, which can be expressed as T(ω,0,0).

[0062] In this embodiment, the transfer function matrix H is constructed in step S3. D When the transfer function matrix H D It is composed of a relative transfer function of L1*L2 dimensions, where L1 represents the total number of microphones in the annular microphone array, L2 represents the total number of rotation angles of one rotation, and L2=360 / d, where d is the rotation angle.

[0063] In this embodiment, the design method of the circular harmonic domain calibration parameter F in step S4 is to make the calibrated circular harmonic domain coefficient as close as possible to the ideal circular harmonic domain coefficient, that is, to minimize the following cost function:

[0064]

[0065] In the above formula, J represents the cost.

[0066] The cost function shown in the above formula is solved by the least squares method to obtain the optimal circular harmonic domain calibration parameter E:

[0067]

[0068] In the above formula, C D is the ideal circular harmonic coefficient, W D is a weighted diagonal matrix (in this embodiment, the unit matrix is used), H D is the transfer function matrix, β is the regularization factor (specifically 0.2 in this embodiment), I s is the identity matrix, the superscript T represents the transpose of the matrix, and the superscript H represents the conjugate transpose of the matrix.

[0069] The annular array beam patterns at 1000 Hz before and after calibration and the ideal model in this embodiment are as follows: Figure 3 As shown, see Figure 3It can be seen that the uncalibrated DSB beamformer at 1000 Hz has poor directivity, significantly different from the ideal value. However, the calibrated DSB beamformer at 1000 Hz has a beam pattern close to the ideal value. This shows that the circular harmonic domain calibration method for an annular microphone array of this embodiment can achieve circular harmonic domain calibration of the annular microphone array, enabling the annular microphone array to more accurately achieve directional sound reception.

[0070] In addition, this embodiment also provides a circular harmonic domain calibration system for an annular microphone array, including:

[0071] A signal sampling program unit, used for collecting sampling signals of the annular microphone array rotating under the sound source;

[0072] A frequency domain conversion program unit, used for converting the sampled signal into frequency domain data;

[0073] The transfer function calculation program unit is used to select a frequency domain data as a benchmark, calculate the relative transfer function between the frequency domain data and construct the transfer function matrix H D ;

[0074] The calibration parameter calculation program unit is used to calculate the calibration parameter according to the transfer function matrix H D The circular harmonic domain calibration parameter E is calculated.

[0075] In this embodiment, the annular microphone array rotates one circle under the sound source, including D rotation angles, each rotation angle includes N sampling points, and each sampling point corresponds to multiple single-frequency signal frequencies. N sampling points refers to 10*f s sampling points, where f s is the sampling frequency of the sampled signal.

[0076] In this embodiment, the frequency domain conversion program unit converts the sampled signal into frequency domain data by:

[0077] The sampling signal is kept in the single-frequency signal frequency ω, rotation angle d, and microphone m group by discrete Fourier transform, and the sampling signal of N sampling points is converted into a set of frequency domain data, and the function expression is:

[0078]

[0079] In the above formula, T(ω,m,d) is the frequency domain data of N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, t(ω,d,m,n) is the sampling signal corresponding to the single-frequency signal frequency ω, the rotation angle d, the sampling point n, and the microphone serial number m, j is an imaginary unit, and e is a natural constant.

[0080] In this embodiment, the transfer function calculation program unit calculates the relative transfer function between frequency domain data using the following function expression:

[0081] H(ω,m,d)=T(ω,m,d) / T0,

[0082] In the above formula, H(ω,m,d) is the relative transfer function of the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone m relative to the benchmark, T(ω,m,d) is the frequency domain data of the N sampling signals corresponding to the single-frequency signal frequency ω, the rotation angle d, and the microphone serial number m, and T0 is the frequency domain data used as the benchmark.

[0083] In this embodiment, the frequency domain data used as a reference is the frequency domain data of N sampling signals corresponding to the rotation angle d being 0 and the microphone serial number m being 0 under the same single-frequency signal frequency ω.

[0084] In this embodiment, the transfer function calculation program unit constructs the transfer function matrix H D When the transfer function matrix H D It is composed of a relative transfer function of L1*L2 dimensions, where L1 represents the total number of microphones in the annular microphone array, L2 represents the total number of rotation angles of one rotation, and L2=360 / d, where d is the rotation angle.

[0085] In this embodiment, the function expression for calculating the circular harmonic domain calibration parameter E by the calibration parameter calculation program unit is:

[0086]

[0087] In the above formula, C D is the ideal circular harmonic coefficient, W D is a weighted diagonal matrix, H D is the transfer function matrix, β is the regularization factor, I s is the identity matrix, the superscript T represents the transpose of the matrix, and the superscript H represents the conjugate transpose of the matrix.

[0088] In addition, this embodiment also provides a circular harmonic domain calibration device for an annular microphone array, including an electric turntable, a frequency-controllable sound source, a sound collection module and a central processing unit. The calibrated annular microphone array is mounted on the electric turntable. The control ends of the electric turntable and the frequency-controllable sound source are respectively connected to the central processing unit. The output end of the annular microphone array is connected to the central processing unit through the sound collection module. The central processing unit is programmed or configured to execute the circular harmonic domain calibration method for the annular microphone array described above.

[0089] In addition, this embodiment further provides a circular harmonic range calibration device for an annular microphone array, comprising a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to execute the circular harmonic range calibration method for an annular microphone array described above.

[0090] In addition, this embodiment further provides a computer-readable storage medium, in which a computer program is stored. The computer program is used to be programmed or configured by a microprocessor to execute the circular harmonic domain calibration method of the annular microphone array described above.

[0091] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program product implemented on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including the instruction device, which implements the function specified in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0092] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A circular harmonic domain calibration method for an annular microphone array, characterized in that: include: S1, collects the sampling signal of the ring microphone array rotating under the sound source; S2, converts the sampled signal into frequency domain data; S3, select a frequency domain data as a benchmark, calculate the relative transfer function between frequency domain data and construct the transfer function matrix , the transfer function matrix It is composed of the relative transfer function of L1*L2 dimensions, where L1 represents the total number of microphones in the annular microphone array, and L2 represents the total number of rotation angles per rotation. d , is the rotation angle; S4, according to the transfer function matrix Calculate the circular harmonic domain calibration parameters : ， In the above formula, is the ideal circular harmonic domain coefficient, is a weighted diagonal matrix, is the transfer function matrix, is the regularization factor, is the identity matrix, the superscript T represents the transpose of the matrix, and the superscript H represents the conjugate transpose of the matrix.

2. The circular harmonic domain calibration method of an annular microphone array according to claim 1, characterized in that: The annular microphone array rotates one circle under the sound source. D rotation angles, each of which contains N sampling points, each sampling point corresponds to multiple single-frequency signal frequencies, N Sampling points refer to 10* f s sampling points, of which f s It is the numerical value of the sampling frequency for collecting the sampling signal.

3. The circular harmonic domain calibration method of an annular microphone array according to claim 1, characterized in that: Converting the sampled signal into frequency domain data in step S2 means: The sampled signal is kept at a single frequency signal frequency through discrete Fourier transform , rotation angle ,microphone Group, N The sampling signal of the sampling points is converted into a set of frequency domain data, and the function expression is: ， In the above formula, Single frequency signal frequency , rotation angle , Microphone serial number Corresponding N The frequency domain data of the sampled signal, Single frequency signal frequency , rotation angle , sampling points and microphone serial number The corresponding sampling signal, j is the imaginary unit, is a natural constant.

4. The circular harmonic domain calibration method of an annular microphone array according to claim 3, characterized in that: The function expression for calculating the relative transfer function between frequency domain data in step S3 is: ， In the above formula, Single frequency signal frequency , rotation angle ,microphone Corresponding N The relative transfer function of the frequency domain data of a sampled signal relative to the reference, Single frequency signal frequency , rotation angle , Microphone serial number Corresponding N The frequency domain data of the sampled signal, is the frequency domain data used as the benchmark.

5. The circular harmonic domain calibration method of an annular microphone array according to claim 3, characterized in that: The frequency domain data used as a reference is the same single frequency signal frequency Lower rotation angle 0, microphone number The corresponding value is 0 N The frequency domain data of the sampled signal.

6. A circular harmonic domain calibration system for an annular microphone array, characterized in that: include: A signal sampling program unit, used for collecting sampling signals of the annular microphone array rotating under the sound source; A frequency domain conversion program unit, used for converting the sampled signal into frequency domain data; The transfer function calculation program unit is used to select a frequency domain data as a benchmark, calculate the relative transfer function between frequency domain data and construct the transfer function matrix , the transfer function matrix It is composed of the relative transfer function of L1*L2 dimensions, where L1 represents the total number of microphones in the annular microphone array, and L2 represents the total number of rotation angles per rotation. d , is the rotation angle; Calibration parameter calculation program unit for calculating the transfer function matrix Calculate the circular harmonic domain calibration parameters : ， In the above formula, is the ideal circular harmonic domain coefficient, is a weighted diagonal matrix, is the transfer function matrix, is the regularization factor, is the identity matrix, the superscript T represents the transpose of the matrix, and the superscript H represents the conjugate transpose of the matrix.

7. A circular harmonic range calibration device for an annular microphone array, characterized in that: The invention comprises an electric turntable, a frequency-controllable sound source, a sound collection module and a central processing unit, wherein the electric turntable is used to set the annular microphone array to be calibrated, the control ends of the electric turntable and the frequency-controllable sound source are respectively connected to the central processing unit, the output end of the annular microphone array is used to be connected to the central processing unit through the sound collection module, and the central processing unit is programmed or configured to execute the circular harmonic domain calibration method of the annular microphone array according to any one of claims 1 to 5.

8. A computer-readable storage medium storing a computer program, wherein: The computer program is used to program or configure a microprocessor to execute the circular harmonic domain calibration method for an annular microphone array according to any one of claims 1 to 5.

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