Acoustic characteristic testing method and system for sound

Abstract

The invention relates to a method and a system for testing an acoustic characteristic of a sound, and belongs to the technical field of sound testing, and the method for testing the acoustic characteristic of the sound comprises the following steps: obtaining a to-be-tested sound signal; according to the to-be-tested sound signal, calculating a sound signal frequency spectrum; calculating a center frequency, an upper limit cut-off frequency and a lower limit cut-off frequency according to the noise signal frequency spectrum, and obtaining a noise signal bandwidth; and performing fast Fourier transform on the to-be-tested sound signal, and obtaining the repetition period of the sound according to the upper limit cut-off frequency or the lower limit cut-off frequency. According to the method and the device, the noise signal bandwidth and the noise repetition period are obtained by calculating the noise signal frequency spectrum, so that the main characteristics of noise acoustics are obtained, the processing speed is relatively high, and the accuracy is relatively high.

Description

Technical Field

[0001] The invention belongs to the technical field of warbling sound testing, and in particular relates to a method and system for testing the acoustic characteristics of warbling sound. Background Art

[0002] Warble tone is a sound signal commonly used in audiology testing. Its core indicators are signal bandwidth and repetition period. It is a signal with a pure tone frequency that changes continuously and periodically around a certain center frequency value. Warble tone does not sound like a pure tone signal with a constant pitch. Instead, it has continuous and periodic pitch changes. It is a frequency modulated signal, generally using a 5Hz sine wave as the modulation wave to modulate a higher frequency sine carrier.

[0003] Warbling is mainly used in sound field audiometry. Sound field audiometry is a hearing test performed by using a loudspeaker in a sound field. It is often used to understand children's hearing, check hearing aids, and evaluate the effects of cochlear implants. Because the standing waves generated by pure tones in the room will affect the accuracy of calibration and test results, and few units have the conditions to perform sound field audiometry in an anechoic chamber, warbling or narrowband noise is often used for sound field audiometry. Warbling can eliminate standing waves and prevent sound waves in the sound field from canceling each other out to produce "dead spots." In most cases, the difference in thresholds measured with pure tones and warbling is very small. In addition, warbling as a sound source signal is also used to measure reverberation time, audiometric thresholds of young children and tinnitus patients, and research on sound source localization ability.

[0004] In audiology testing, the use of warbling has two main advantages: first, warbling can attract more attention and increase children's interest in sound; second, the use of warbling can reduce the generation of standing waves, thus becoming an important test sound. Warbling is used as a stimulus sound when measuring reverberation time, sound field audiometry, tinnitus patients, and testing the hearing threshold of children or the elderly who are insensitive to pure tones.

[0005] For example, a Chinese patent with publication number CN102835959B discloses a pure tone hearing test system formed by a digital sound card. The system is compiled on a computer, and the software writes pure tones, warble tones, narrowband noise, broadband noise, and speech signals to be output through the sound card, and cooperates with the display of behavioral audiometry pictures to achieve the assessment of the patient's hearing loss, thus forming a test system with software as the main control.

[0006] However, the current test methods for warbling tones are relatively simple, and there is no method that can accurately measure the signal bandwidth and repetition period of the warbling tones.

[0007] Therefore, it is urgent to develop a method and system for testing the acoustic characteristics of warbling sound to solve the problems in the prior art. Summary of the invention

[0008] The purpose of the present invention is to provide a method and system for testing the acoustic characteristics of warb, by calculating the warb signal spectrum, obtaining the signal bandwidth of the warb and the repetition period of the warb, thereby obtaining the main acoustic characteristics of the warb, in order to solve the problem raised in the above background technology that there is currently no method or system that can accurately measure the signal bandwidth and repetition period of the warb.

[0009] In order to solve the above technical problems, the specific technical solutions of the present invention are as follows:

[0010] A method for testing the acoustic characteristics of warbling sound comprises the following steps:

[0011] Acquire a warbling tone signal to be tested; calculate a frequency spectrum of the warbling tone signal according to the warbling tone signal to be tested;

[0012] According to the warbling signal spectrum, the center frequency, the upper cutoff frequency and the lower cutoff frequency are calculated to obtain the signal bandwidth of the warbling sound;

[0013] Perform fast Fourier transform on the warbling tone signal to be measured, and obtain the repetition period of the warbling tone according to the upper cutoff frequency or the lower cutoff frequency.

[0014] Further, the step of calculating the center frequency, the upper cutoff frequency, and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling sound comprises the following steps:

[0015] According to the spectrum of the warbling signal, a spectrum peak is obtained; according to the spectrum peak, a cutoff frequency value is obtained;

[0016] According to the cutoff frequency value, an upper cutoff frequency and a lower cutoff frequency corresponding to the cutoff frequency value are obtained;

[0017] Calculate the signal bandwidth of the warbling tone according to the upper cutoff frequency and the lower cutoff frequency;

[0018] Wherein, the spectrum peaks are two peaks in the spectrum of the warbling signal;

[0019] The cut-off frequency value is obtained by calculating the sum of the spectrum peak value and the relative peak value;

[0020] The upper cut-off frequency is the maximum frequency corresponding to the cut-off frequency value, and the lower cut-off frequency is the minimum frequency corresponding to the cut-off frequency value.

[0021] Furthermore, the signal bandwidth is calculated by the following formula:

[0022] Δf = f H -f L ;

[0023] Where Δf is the signal bandwidth, f H is the upper cutoff frequency, f Lis the lower cut-off frequency.

[0024] Further, the method of performing a fast Fourier transform on the warbling tone signal to be tested and obtaining the repetition period of the warbling tone according to the upper cutoff frequency comprises the following steps:

[0025] Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the upper cutoff frequency in each time interval;

[0026] Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period;

[0027] Wherein, the repetition period of the warbling tone is the variation period of the signal strength;

[0028] Or, the method of performing a fast Fourier transform on the warbling tone signal to be measured and obtaining the repetition period of the warbling tone according to the lower cutoff frequency comprises the following steps:

[0029] Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the lower cutoff frequency in each time interval;

[0030] Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period;

[0031] The repetition period of the warbling tone is the variation period of the signal strength.

[0032] Further, the time interval of the fast Fourier transform analysis is less than or equal to 100 ms;

[0033] The variation period of the signal strength is the time difference between the peaks of the signal strength.

[0034] Further, the method of calculating the frequency spectrum of the warbling signal according to the warbling signal to be measured comprises the following steps:

[0035] Perform FFT transformation on the warbling tone signal to be measured to obtain the frequency spectrum of the warbling tone signal.

[0036] Furthermore, the step of obtaining the warbling signal to be measured and calculating the frequency spectrum of the warbling signal according to the warbling signal to be measured comprises the following steps:

[0037] Collecting data samples of the same warbling tone signal to be tested multiple times;

[0038] Perform FFT transformation on each data sample to obtain the frequency spectrum of each data sample;

[0039] The spectra obtained by multiple FFT transformations are averaged at the corresponding frequency points to obtain the final warbling signal spectrum.

[0040] A warbling sound acoustic characteristic testing system, comprising:

[0041] An acquisition module, the acquisition module is used to obtain the warbling tone signal to be tested;

[0042] A processing module, the processing module is used to calculate the warbling signal spectrum according to the warbling signal to be tested; calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling; and perform a fast Fourier transform on the warbling signal to be tested, and obtain the repetition period of the warbling according to the upper cutoff frequency or the lower cutoff frequency.

[0043] Furthermore, the acquisition module includes:

[0044] A microphone, used for collecting the warbling signal to be measured;

[0045] The processing module comprises:

[0046] The host computer is used to calculate the warbling signal spectrum according to the warbling signal to be tested; calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling; and perform fast Fourier transform on the warbling signal to be tested, and obtain the repetition period of the warbling according to the upper cutoff frequency or the lower cutoff frequency;

[0047] The processing module also includes:

[0048] An audio circuit, used for preprocessing the warbling tone signal to be tested;

[0049] Main control module, used for data transmission with the host computer;

[0050] The microphone is electrically connected to the audio circuit, the audio circuit is electrically connected to the main control module, and the main control module is communicatively connected to the host computer.

[0051] Further, the step of calculating the center frequency, the upper cutoff frequency, and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling sound comprises the following steps:

[0052] According to the spectrum of the warbling signal, a spectrum peak is obtained; according to the spectrum peak, a cutoff frequency value is obtained;

[0053] According to the cutoff frequency value, an upper cutoff frequency and a lower cutoff frequency corresponding to the cutoff frequency value are obtained;

[0054] Calculate the signal bandwidth of the warbling tone according to the upper cutoff frequency and the lower cutoff frequency;

[0055] Wherein, the spectrum peaks are two peaks in the spectrum of the warbling signal;

[0056] The cut-off frequency value is obtained by calculating the sum of the spectrum peak value and the relative peak value;

[0057] The upper cut-off frequency is the maximum frequency corresponding to the cut-off frequency value, and the lower cut-off frequency is the minimum frequency corresponding to the cut-off frequency value;

[0058] The signal bandwidth is calculated by the following formula:

[0059] Δf = f H -f L ;

[0060] Where Δf is the signal bandwidth, f H is the upper cutoff frequency, f L is the lower cut-off frequency;

[0061] The method of performing a fast Fourier transform on the warbling tone signal to be tested and obtaining the repetition period of the warbling tone according to the upper cutoff frequency comprises the following steps:

[0062] Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the upper cutoff frequency in each time interval;

[0063] Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period;

[0064] Wherein, the repetition period of the warbling tone is the variation period of the signal strength;

[0065] Or, the method of performing a fast Fourier transform on the warbling tone signal to be measured and obtaining the repetition period of the warbling tone according to the lower cutoff frequency comprises the following steps:

[0066] Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the lower cutoff frequency in each time interval;

[0067] Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period;

[0068] The repetition period of the warbling tone is the variation period of the signal strength.

[0069] The present invention has the following advantages:

[0070] (1) The present application provides a method and a system for testing the acoustic characteristics of warbling sound. The method can calculate the frequency spectrum of the warbling sound signal, calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency to obtain the signal bandwidth of the warbling sound; and obtain the repetition period of the warbling sound based on the upper cutoff frequency or the lower cutoff frequency, thereby obtaining the main acoustic characteristics of the warbling sound, and the method has a fast processing speed and a high accuracy.

[0071] (2) The present application can obtain a relatively accurate warbling signal spectrum by performing multiple FFT transformations and averaging, so as to further improve the accuracy of the warbling signal bandwidth and the warbling repetition period obtained by the present application.

[0072] Other features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 It is a schematic diagram of the overall process of the present invention;

[0074] Figure 2 It is the FFT average spectrum diagram of the present invention;

[0075] Figure 3 It is the FFT spectrum diagram of the present invention at a certain moment;

[0076] Figure 4 It is the FFT spectrum diagram of the present invention at a certain moment;

[0077] Figure 5 It is the FFT spectrum diagram of the present invention at a certain moment;

[0078] Figure 6 is a signal strength histogram at each moment of the present invention;

[0079] Figure 7 It is a schematic diagram of the system structure of the present invention. DETAILED DESCRIPTION

[0080] In order to better understand the purpose, structure and function of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0081] A method for testing the acoustic characteristics of warbling sound comprises the following steps:

[0082] S1: obtaining a warbling tone signal to be measured, and calculating a frequency spectrum of the warbling tone signal according to the warbling tone signal to be measured;

[0083] S2: Calculate the center frequency, upper cutoff frequency and lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling sound;

[0084] S3: Perform fast Fourier transform on the warbling tone signal to be measured, and obtain the repetition period of the warbling tone according to the upper cutoff frequency or the lower cutoff frequency.

[0085] The warbling signal to be measured in S1 can be collected by a microphone.

[0086] In S1, the frequency spectrum of the warbling signal is calculated according to the warbling signal to be measured, including the following steps:

[0087] Perform FFT transformation on the warbling tone signal to be measured to obtain the frequency spectrum of the warbling tone signal.

[0088] The calculation process of the FFT transformation may include the following steps:

[0089] The input signal is sampled to obtain a set of discrete time samples;

[0090] Divide this set of samples into subsequences of length N;

[0091] Perform DFT (Discrete Fourier Transform) operation on each subsequence to obtain the frequency domain representation of the subsequence;

[0092] The frequency domain representations of all subsequences are superimposed to obtain the frequency domain representation of the entire signal.

[0093] In this embodiment, in order to improve the reliability of spectrum estimation, the warbling signal to be measured is collected multiple times and FFT transformation is performed, and then the results of the multiple transformations are averaged.

[0094] Specifically, the step of obtaining the warbling signal to be measured in S1 and calculating the frequency spectrum of the warbling signal according to the warbling signal to be measured includes the following steps:

[0095] Collecting data samples of the same warbling tone signal to be tested multiple times;

[0096] Perform FFT transformation on each data sample to obtain the frequency spectrum of each data sample;

[0097] The spectra obtained by multiple FFT transformations are averaged at the corresponding frequency points to obtain the final warbling signal spectrum.

[0098] The method of this embodiment can effectively suppress random noise, reduce the impact of random errors, obtain more accurate frequency information, and more clearly identify the spectral characteristics of the warbling sound, so as to improve the accuracy and stability of spectrum estimation, making the spectral characteristics of the warbling sound more stable and reliable.

[0099] In S2, according to the warbling signal spectrum, the center frequency, the upper cutoff frequency and the lower cutoff frequency are calculated to obtain the signal bandwidth of the warbling sound, including the following steps:

[0100] S21: acquiring spectrum peaks according to the spectrum of the warbling signal; wherein the spectrum peaks are two peaks in the spectrum of the warbling signal;

[0101] S22: Obtain the cutoff frequency value according to the spectrum peak value;

[0102] S23: according to the cutoff frequency value, obtaining an upper cutoff frequency and a lower cutoff frequency corresponding to the cutoff frequency value;

[0103] S24: Calculate the signal bandwidth of the warbling tone according to the upper cutoff frequency and the lower cutoff frequency.

[0104] Specifically, in this embodiment, taking a warbling tone with a center frequency of 1 kHz and a bandwidth of 100 Hz as an example, after averaging the FFT spectrum of each data sample 200 times, the graph is as follows: Figure 2 As shown in the figure, it can be seen that there is a spectrum peak point at each of the left and right ends of the upper part of the spectrum curve, and the amplitude value corresponding to the spectrum peak point is the spectrum peak value. In this embodiment, the spectrum peak value is 102dB.

[0105] The S22 cutoff frequency value is obtained by calculating the sum of the spectrum peak and the relative peak. In this embodiment, the relative peak is preferably -3dB, and the cutoff frequency value is 99dB. Optionally, the relative peak can be set as needed, and can be less than 0dB, greater than -5dB, or less than -5% of the spectrum peak.

[0106] The upper cut-off frequency in S23 is the maximum frequency corresponding to the cut-off frequency value, and the lower cut-off frequency is the minimum frequency corresponding to the cut-off frequency value.

[0107] like Figure 2 As shown, in this embodiment, the lower limit cut-off frequency f L is 0.95kHz, the upper cut-off frequency f H is 1.05kHz. Obviously, f L = 0.95kHz, f H = 1.05kHz, bandwidth is f H -f L = 0.1kHz.

[0108] The signal bandwidth Δf in S24 is calculated by the following formula:

[0109] Δf = f H -f L ;

[0110] Where Δf is the signal bandwidth, f H is the upper cutoff frequency, f L is the lower cut-off frequency.

[0111] The calculation formula of the center frequency f0 includes the following:

[0112] f0 = (f H + f L ) / 2

[0113] Where f0 is the center frequency, f H is the upper cutoff frequency, f L is the lower cut-off frequency.

[0114] In S3, the warbling signal to be tested is subjected to a fast Fourier transform, and the repetition period of the warbling is obtained according to the upper cutoff frequency or the lower cutoff frequency, including the following steps:

[0115] Performing a fast Fourier transform (FFT) analysis on the warbling tone signal to be tested to obtain the signal strength Y corresponding to the upper cutoff frequency or the lower cutoff frequency in each time interval;

[0116] The repetition period of the warbling tone is obtained according to the variation period of the signal strength.

[0117] The time interval τ of the fast Fourier transform analysis is less than or equal to 100 ms, the signal strength Y is the amplitude value corresponding to the upper cutoff frequency or the lower cutoff frequency, and the repetition period of the warbling tone is the variation period of the signal strength Y.

[0118] In this embodiment, at 1τ, 2τ, 3τ, ..., nτ, FFT analysis is performed on the signal segment in the previous time interval to obtain the signal strength Y1, Y2, Y3, ..., Yn corresponding to the upper cutoff frequency or the lower cutoff frequency. Figures 3 to 5 , which is a frequency spectrum diagram after fast Fourier transform (FFT) analysis at some moments in this embodiment, from which it can be known that the signal strength corresponding to the upper cutoff frequency or the lower cutoff frequency.

[0119] like Figure 6 As shown, it is the signal strength data at each moment obtained by the present application. In this embodiment, the variation period of the signal strength is the time difference between the peaks of the signal strength.

[0120] A warbling sound acoustic characteristic testing system, comprising:

[0121] An acquisition module, the acquisition module is used to obtain the warbling tone signal to be tested;

[0122] A processing module, the processing module is used to calculate the warbling signal spectrum according to the warbling signal to be tested; calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling; and perform a fast Fourier transform on the warbling signal to be tested, and obtain the repetition period of the warbling according to the upper cutoff frequency or the lower cutoff frequency.

[0123] Specifically, Figure 7 As shown, the acquisition module includes:

[0124] A microphone, used for collecting the warbling signal to be measured;

[0125] The processing module comprises:

[0126] The host computer is used to calculate the warbling signal spectrum according to the warbling signal to be tested; calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling; and perform fast Fourier transform on the warbling signal to be tested, and obtain the repetition period of the warbling according to the upper cutoff frequency or the lower cutoff frequency;

[0127] An audio circuit, used for preprocessing the warbling tone signal to be tested;

[0128] Main control module, used for data transmission with the host computer;

[0129] The microphone is electrically connected to the audio circuit, the audio circuit is electrically connected to the main control module, and the main control module is communicatively connected to the host computer.

[0130] In this embodiment, the main control module transmits data with the host computer via a USB data cable; the preprocessing of the audio circuit includes filtering, analog-to-digital conversion, signal enhancement or data fusion, etc., which are existing technologies and will not be repeated in this application.

[0131] The host computer calculates the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling sound, including the following steps:

[0132] According to the spectrum of the warbling signal, a spectrum peak is obtained; according to the spectrum peak, a cutoff frequency value is obtained;

[0133] According to the cutoff frequency value, an upper cutoff frequency and a lower cutoff frequency corresponding to the cutoff frequency value are obtained;

[0134] Calculate the signal bandwidth of the warbling tone according to the upper cutoff frequency and the lower cutoff frequency;

[0135] Wherein, the spectrum peaks are two peaks in the spectrum of the warbling signal;

[0136] The cut-off frequency value is obtained by calculating the sum of the spectrum peak value and the relative peak value;

[0137] The upper cut-off frequency is the maximum frequency corresponding to the cut-off frequency value, and the lower cut-off frequency is the minimum frequency corresponding to the cut-off frequency value;

[0138] The signal bandwidth is calculated by the following formula:

[0139] Δf = f H -f L ;

[0140] Where Δf is the signal bandwidth, f H is the upper cutoff frequency, f L is the lower cut-off frequency;

[0141] The method of performing a fast Fourier transform on the warbling tone signal to be tested and obtaining the repetition period of the warbling tone according to the upper cutoff frequency comprises the following steps:

[0142] Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the upper cutoff frequency in each time interval;

[0143] Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period;

[0144] Wherein, the repetition period of the warbling tone is the variation period of the signal strength;

[0145] Or, the method of performing a fast Fourier transform on the warbling tone signal to be measured and obtaining the repetition period of the warbling tone according to the lower cutoff frequency comprises the following steps:

[0146] Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the lower cutoff frequency in each time interval;

[0147] Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period;

[0148] The repetition period of the warbling tone is the variation period of the signal strength.

[0149] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for testing the acoustic characteristics of warble sound, characterized in that: The steps include: Acquire a warbling tone signal to be tested; calculate a frequency spectrum of the warbling tone signal according to the warbling tone signal to be tested; According to the warbling signal spectrum, the center frequency, the upper cutoff frequency and the lower cutoff frequency are calculated to obtain the signal bandwidth of the warbling sound; Perform fast Fourier transform on the warbling tone signal to be measured, and obtain the repetition period of the warbling tone according to the upper cutoff frequency or the lower cutoff frequency.

2. The method for testing the acoustic characteristics of warble sound according to claim 1, characterized in that: The method of calculating the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling sound comprises the following steps: According to the spectrum of the warbling signal, a spectrum peak is obtained; according to the spectrum peak, a cutoff frequency value is obtained; According to the cutoff frequency value, an upper cutoff frequency and a lower cutoff frequency corresponding to the cutoff frequency value are obtained; Calculate the signal bandwidth of the warbling tone according to the upper cutoff frequency and the lower cutoff frequency; Wherein, the spectrum peaks are two peaks in the spectrum of the warbling signal; The cut-off frequency value is obtained by calculating the sum of the spectrum peak value and the relative peak value; The upper cut-off frequency is the maximum frequency corresponding to the cut-off frequency value, and the lower cut-off frequency is the minimum frequency corresponding to the cut-off frequency value.

3. The method for testing the acoustic characteristics of warble sound according to claim 2, characterized in that: The signal bandwidth is calculated by the following formula: Δf = f H - f L ; Where Δf is the signal bandwidth, f H is the upper cutoff frequency, f L is the lower cutoff frequency.

4. The method for testing the acoustic characteristics of warble sound according to claim 2, characterized in that: Performing a fast Fourier transform on the warbling signal to be tested, and obtaining the repetition period of the warbling according to the upper cutoff frequency, includes the following steps: Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the upper cutoff frequency in each time interval; Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period; Wherein, the repetition period of the warbling tone is the variation period of the signal strength; Or, performing a fast Fourier transform on the warbling tone signal to be measured, and obtaining the repetition period of the warbling tone according to the lower limit cutoff frequency, including the following steps: Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the lower cutoff frequency in each time interval; Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period; The repetition period of the warbling tone is the variation period of the signal strength.

5. The method for testing the acoustic characteristics of warble sound according to claim 4, characterized in that: The time interval of the fast Fourier transform analysis is less than or equal to 100 ms; The variation period of the signal strength is the time difference between the peaks of the signal strength.

6. The method for testing the acoustic characteristics of warble sound according to any one of claims 1 to 5, characterized in that: The method of calculating the frequency spectrum of the warbling signal according to the warbling signal to be measured comprises the following steps: Perform FFT transformation on the warbling tone signal to be measured to obtain the frequency spectrum of the warbling tone signal.

7. The method for testing the acoustic characteristics of warbling sound according to any one of claims 1 to 5, characterized in that: The method of obtaining the warbling signal to be measured and calculating the frequency spectrum of the warbling signal according to the warbling signal to be measured comprises the following steps: Collecting data samples of the same warbling tone signal to be tested multiple times; Perform FFT transformation on each data sample to obtain the frequency spectrum of each data sample; The spectra obtained by multiple FFT transformations are averaged at the corresponding frequency points to obtain the final warbling signal spectrum.

8. A warbling acoustic characteristics testing system, characterized in that: include: An acquisition module, the acquisition module is used to obtain the warbling tone signal to be tested; A processing module, the processing module is used to calculate the warbling signal spectrum according to the warbling signal to be tested; calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling; and perform a fast Fourier transform on the warbling signal to be tested, and obtain the repetition period of the warbling according to the upper cutoff frequency or the lower cutoff frequency.

9. The warbling acoustic characteristic testing system according to claim 8, characterized in that: The acquisition module comprises: A microphone, used for collecting the warbling signal to be measured; The processing module comprises: The host computer is used to calculate the warbling signal spectrum according to the warbling signal to be tested; calculate the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling; and perform fast Fourier transform on the warbling signal to be tested, and obtain the repetition period of the warbling according to the upper cutoff frequency or the lower cutoff frequency; The processing module also includes: An audio circuit, used for preprocessing the warbling tone signal to be tested; Main control module, used for data transmission with the host computer; The microphone is electrically connected to the audio circuit, the audio circuit is electrically connected to the main control module, and the main control module is communicatively connected to the host computer.

10. The warbling acoustic characteristic testing system according to claim 8 or 9, characterized in that: The method of calculating the center frequency, the upper cutoff frequency and the lower cutoff frequency according to the warbling signal spectrum to obtain the signal bandwidth of the warbling sound comprises the following steps: According to the spectrum of the warbling signal, a spectrum peak is obtained; according to the spectrum peak, a cutoff frequency value is obtained; According to the cutoff frequency value, an upper cutoff frequency and a lower cutoff frequency corresponding to the cutoff frequency value are obtained; Calculate the signal bandwidth of the warbling tone according to the upper cutoff frequency and the lower cutoff frequency; Wherein, the spectrum peaks are two peaks in the spectrum of the warbling signal; The cut-off frequency value is obtained by calculating the sum of the spectrum peak value and the relative peak value; The upper cut-off frequency is the maximum frequency corresponding to the cut-off frequency value, and the lower cut-off frequency is the minimum frequency corresponding to the cut-off frequency value; The signal bandwidth is calculated by the following formula: Δf = f H - f L ; Where Δf is the signal bandwidth, f H is the upper cutoff frequency, f L is the lower cut-off frequency; The method of performing a fast Fourier transform on the warbling tone signal to be tested and obtaining the repetition period of the warbling tone according to the upper cutoff frequency comprises the following steps: Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the upper cutoff frequency in each time interval; Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period; Wherein, the repetition period of the warbling tone is the variation period of the signal strength; Or, the method of performing a fast Fourier transform on the warbling tone signal to be measured and obtaining the repetition period of the warbling tone according to the lower cutoff frequency comprises the following steps: Performing fast Fourier transform analysis on the warbling tone signal to be tested to obtain the signal strength corresponding to the lower cutoff frequency in each time interval; Obtaining a repetition period of the warbling tone according to the obtained signal strength variation period; The repetition period of the warbling tone is the variation period of the signal strength.

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