Audio data acquisition method, system, electronic device and storage medium based on DAS

Abstract

The present invention relates to the field of fiber optic sensing, and more specifically, to a DAS-based audio data acquisition method, system, electronic device, and storage medium. The acquisition method comprises: determining a baseline noise threshold in an optical cable to be tested; collecting real-time audio data and real-time energy at the current sampling time point of the optical cable to be tested; updating the baseline noise threshold using the baseline energy in the real-time audio data; obtaining the starting point of a valid signal in the real-time audio data based on the real-time energy and the updated baseline noise threshold; amplifying the real-time audio data collected after the starting point; and using the amplified real-time audio data as valid audio data. Compared to the prior art, the present invention obtains a baseline noise threshold that includes system noise, and uses a baseline energy that includes external noise to update the baseline noise threshold, thereby acquiring a valid signal based on the updated baseline noise threshold and real-time energy. The method is computationally simple and does not require complex algorithms or additional hardware.

Description

Technical Field

[0001] The present invention relates to the field of optical fiber sensing, and more specifically, to a DAS-based audio data acquisition method, system, electronic device, and storage medium. Background Art

[0002] Distributed acoustic sensing (DAS) is a sensing technology that uses the Rayleigh backscattering interference effect of optical fibers to achieve continuous distributed detection of acoustic signals. It has broad application prospects in perimeter security, pipeline monitoring, seismic exploration, and other fields. The signal-to-noise ratio of audio data in a DAS system is affected by multiple factors, including internal system noise and external environmental noise. A low signal-to-noise ratio makes the audio data difficult to identify, which in turn affects the analysis of the DAS system. Existing DAS systems typically use filtering and noise reduction technologies to improve the signal-to-noise ratio, but these methods often require complex algorithms and hardware support and are difficult to adapt to complex and changing environments. Summary of the Invention

[0003] The present invention aims to overcome at least one of the above-mentioned defects of the prior art and provide a DAS-based audio data acquisition method, system, electronic device and storage medium for effectively improving the signal-to-noise ratio of audio data acquisition through simple hardware and algorithms.

[0004] The technical solution adopted by the present invention is:

[0005] According to a first aspect of the present invention, a method for acquiring audio data based on DAS is provided, the method comprising:

[0006] Obtain the baseline noise threshold of the DAS system in the optical cable under test;

[0007] Collecting real-time audio data of the optical cable to be tested at a current sampling time point through a DAS system, and obtaining real-time energy at the current sampling time point based on the real-time audio data;

[0008] Obtaining a reference energy corresponding to the real-time audio data; the reference energy is an audio energy value within a period of time before the current sampling time point;

[0009] updating the reference noise threshold according to the reference energy;

[0010] Determining whether there is a valid signal in the real-time audio data according to the real-time energy and the updated reference noise threshold;

[0011] If there is a valid signal, taking the current sampling time point as the starting point of the valid signal, and amplifying the real-time audio data collected after the starting point;

[0012] The amplified real-time audio data is used as valid audio data.

[0013] The baseline noise threshold of the DAS system is collected in advance when there is no valid signal in the optical cable to be tested, and used as one of the criteria for judging whether the audio data obtained in the optical cable to be tested is a valid signal. Then, real-time audio data of the optical cable to be tested is obtained, and the real-time energy and baseline energy of the real-time audio data are calculated, wherein the baseline energy is the audio energy value in a period of time before the current sampling time point, reflecting the audio energy and noise conditions in the optical cable to be tested before the current sampling time point. Therefore, the baseline noise threshold is updated by the baseline energy, so that the baseline noise threshold can be adjusted based on the actual noise conditions, thereby better realizing the judgment of the valid signal. At the same time, after determining the starting point of the valid signal, the valid signal is amplified. When the valid signal is amplified and the system noise remains unchanged, the signal-to-noise ratio of the real-time audio data is increased. Since the calculation operation of the present invention is simple, there is no need to adopt a complex algorithm, and no additional hardware is required to achieve an improvement in the signal-to-noise ratio of the audio data.

[0014] Furthermore, obtaining a baseline noise threshold of the DAS system in the optical cable to be tested specifically includes:

[0015] Collecting reference audio data of the optical cable to be tested through a DAS system; the reference audio data is audio data when there is no valid signal in the optical cable to be tested;

[0016] According to a preset first data window, obtaining a first window of audio data within a preset first time range from the reference audio data;

[0017] Obtaining noise energy of the audio data in the first window according to the mean square error of the audio data in the first window;

[0018] The reference noise threshold is obtained according to the noise energy.

[0019] The reference audio data is collected through the first data window. By setting the size of the first data window and the collection position of the first data window in the reference audio data, the first window audio data can be flexibly and accurately obtained from the reference audio data, so that the first window audio data can more accurately represent the noise energy of the system.

[0020] Furthermore, the obtaining of the reference energy corresponding to the real-time audio data specifically includes:

[0021] According to a preset second data window, obtaining second window audio data of a second time range from the audio data before the current sampling time point;

[0022] Calculate the mean square error of the second window audio data, and obtain the reference energy corresponding to the real-time audio data according to the mean square error of the second window audio data.

[0023] By setting the second data window, audio data before the current sampling time point is collected, and based on the mean square error of the collected second window audio data, a reference energy corresponding to the real-time audio data is obtained, so that the reference energy can effectively reflect the noise and audio energy conditions in the audio data before the current sampling time point, and then based on the reference energy, the reference noise threshold can be better adjusted.

[0024] Further, the updating of the baseline noise threshold according to the baseline energy specifically includes:

[0025] comparing the reference energy with the reference noise threshold;

[0026] If the reference energy is less than the reference noise threshold, setting the reference noise threshold to be equal to the reference energy;

[0027] If the reference energy is greater than or equal to the reference noise threshold, the reference noise threshold is kept unchanged.

[0028] The reference noise threshold is updated according to the reference energy, so that the reference noise threshold can change with the change of the reference energy, thereby enabling the determination of the valid signal to be achieved more accurately.

[0029] Furthermore, judging whether there is a valid signal in the real-time audio data according to the real-time energy and the updated reference noise threshold specifically includes:

[0030] When the real-time energy is greater than the updated reference noise threshold, determining that there is a valid signal in the real-time audio data;

[0031] When the real-time energy is less than or equal to the updated reference noise threshold, it is determined that no valid signal exists in the real-time audio data.

[0032] Furthermore, the real-time audio data collected after the starting point is amplified, specifically:

[0033] The audio data collected after the starting point is amplified according to a preset magnification.

[0034] Furthermore, after amplifying the real-time audio data collected after the starting point, the method further includes:

[0035] Continue to collect real-time audio data after the starting point, and obtain corresponding reference energy according to the real-time audio data after the starting point;

[0036] further updating the updated baseline noise threshold according to the baseline energy after the starting point;

[0037] Determining whether there is a valid signal in the real-time audio data after the starting point based on the real-time energy and the further updated reference noise threshold;

[0038] If there is no valid signal, the sampling time point corresponding to the real-time audio data after the starting point is used as the end point of the valid signal, and the amplification of the real-time audio data collected after the end point is stopped.

[0039] According to a second aspect of the present invention, the present invention further provides a DAS-based audio data acquisition system, the acquisition system comprising:

[0040] A reference threshold acquisition module is used to obtain a reference noise threshold of the DAS system in the optical cable to be tested;

[0041] An audio data acquisition module is used to collect real-time audio data of the optical cable to be tested at a current sampling time point through a DAS system, and obtain real-time energy at the current sampling time point based on the real-time audio data;

[0042] An audio energy calculation module is used to obtain a reference energy corresponding to the real-time audio data; the reference energy is the audio energy value within a period of time before the current sampling time point;

[0043] a noise threshold updating module, configured to update the reference noise threshold according to the reference energy;

[0044] The valid signal confirmation module is used to determine whether there is a valid signal in the real-time audio data based on the real-time energy and the updated baseline noise threshold; if there is a valid signal, use the current sampling time point as the starting point of the valid signal, amplify the real-time audio data collected after the starting point; and use the amplified real-time audio data as valid audio data.

[0045] According to the third aspect of the present invention, the present invention also provides an electronic device, including a memory and a processor, wherein the memory stores computer-readable instructions, and the processor executes the computer-readable instructions to implement the DAS-based audio data acquisition method described in the first aspect above.

[0046] According to a fourth aspect of the present invention, the present invention further provides a computer storage medium having computer-readable instructions stored thereon, which, when executed, implements the DAS-based audio data acquisition method described in the first aspect above.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The present invention pre-collects a baseline noise threshold of the DAS system in the optical cable to be tested. The baseline noise threshold reflects the system noise of the DAS system. Therefore, the baseline noise threshold can be used as one of the criteria for judging whether the audio data obtained in the optical cable to be tested is a valid signal. Then, the real-time audio data at the current sampling time point in the optical cable to be tested is obtained, and the baseline energy is calculated. The baseline energy reflects the audio energy situation before the current sampling time point. The baseline noise threshold is updated according to the baseline energy, so that the baseline noise threshold can be adaptively adjusted according to the actual audio energy situation, thereby better achieving the acquisition of valid signals. Finally, the obtained valid signal is amplified. When the valid signal is amplified and the system noise remains unchanged, the signal-to-noise ratio of the real-time audio data is increased. Since the calculation operation of the present invention is simple, there is no need to adopt a complex algorithm, and no additional hardware is required to achieve an improvement in the signal-to-noise ratio of the audio data. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 Flow chart of the steps of the acquisition method of the present invention.

[0050] Figure 2 Flowchart of the steps for obtaining the baseline noise threshold of the present invention.

[0051] Figure 3 This is a flow chart of the steps for obtaining the reference energy of the present invention.

[0052] Figure 4 Flow chart of the steps for updating the baseline noise threshold of the present invention.

[0053] Figure 5 This is a flow chart of the steps for valid signal determination of the present invention.

[0054] Figure 6 This is a system structure diagram of the acquisition system of the present invention.

[0055] Figure 7 This is a device structure diagram of the electronic device of the present invention.

[0056] The accompanying drawings are marked with: reference threshold acquisition module 11, audio data acquisition module 12, audio energy calculation module 13, noise threshold update module 14, valid signal confirmation module 15, memory 21, processor 22, bus 23, and communication interface 24. DETAILED DESCRIPTION

[0057] The accompanying drawings are for illustrative purposes only and are not to be construed as limiting the present invention. To better illustrate the following embodiments, some components in the accompanying drawings may be omitted, enlarged, or reduced in size, and do not represent actual product dimensions. Those skilled in the art will appreciate that some well-known structures and their descriptions may be omitted from the accompanying drawings.

[0058] Example 1

[0059] Distributed fiber acoustic sensing (DAS) technology utilizes the Rayleigh backscattering interferometry effect of optical fibers to achieve continuous, distributed detection of acoustic signals. When sound or vibration causes a linear phase shift in the interfering light at a specific location on the fiber, quantitative measurement of the external sound or vibration can be achieved by extracting and demodulating the interference signal at that location at different times. Therefore, DAS technology has broad application prospects in perimeter security, pipeline monitoring, seismic exploration, and other fields.

[0060] However, in actual applications, the monitoring of DAS systems is affected by the signal-to-noise ratio of the audio data obtained by demodulating the interference signal. The signal-to-noise ratio refers to the ratio of the power of the effective signal to the noise power. Therefore, the lower the signal-to-noise ratio, the more difficult it is for the DAS equipment to identify the audio data. The signal-to-noise ratio of the audio data of the DAS system is affected by multiple factors, including internal system noise and external environmental noise.

[0061] Internal system noise can include factors such as the laser's linewidth and power stability. System noise is often static and persists even when no valid signal is present in the corresponding optical fiber. External environmental noise, on the other hand, can include sound waves and vibrations generated by various environmental changes. External environmental noise is dynamic and changes with environmental changes. Therefore, it is necessary to improve the signal-to-noise ratio of audio data through appropriate methods.

[0062] Existing DAS systems usually use filtering, noise reduction and other technologies to improve the signal-to-noise ratio, but these methods often require complex algorithms and hardware support. At the same time, since corresponding algorithms and hardware are needed to support these methods, it is difficult to expand their application to adapt to complex and changing environments.

[0063] Therefore, developing a simple, effective, easy-to-implement and adaptable method to improve the signal-to-noise ratio of DAS audio data is of great significance for improving the audio restoration effect of DAS equipment.

[0064] This embodiment provides a technical solution that can solve the above-mentioned existing technical problems, which is described in detail below with reference to the accompanying drawings.

[0065] like Figure 1 As shown, this embodiment provides a method for acquiring audio data based on DAS, and the acquisition method may specifically include:

[0066] S1: Obtain the baseline noise threshold of the DAS system in the optical cable under test;

[0067] In this embodiment, the DAS system is primarily used to collect acoustic signals affecting the optical cable under test. Therefore, the effective signal in this embodiment primarily refers to the acoustic signal received by the optical cable under test. To effectively extract the effective signal from the optical cable under test, it is necessary to eliminate noise from the various signals received by the optical cable under test.

[0068] In this embodiment, the reference noise threshold is the noise condition of the DAS system in the optical cable to be tested. It can be understood that the reference noise threshold represents the system noise condition generated by the DAS system itself after the DAS system is connected to the optical cable to be tested, without interference from other external factors.

[0069] Specifically, in this embodiment, the baseline noise threshold of the DAS system is obtained according to the first window audio data, such as Figure 2 Specifically, it may include:

[0070] S11: Collecting reference audio data of the optical cable to be tested through the DAS system;

[0071] In this embodiment, the reference audio data is audio data collected when there is no valid signal in the optical cable under test; that is, the audio data collected after the DAS system is connected to the optical cable under test and without interference from other external factors. Preferably, to ensure data reliability, the reference audio data can be collected over a longer period of time.

[0072] As described above, the reference noise threshold represents the noise generated inside the DAS system without interference from other external factors, and thus the reference noise threshold can be obtained through reference audio data when the optical cable to be tested contains no valid signal.

[0073] S12: Acquire a first window of audio data within a preset first time range from the reference audio data according to a preset first data window;

[0074] Specifically, in this step, the reference audio data does not contain a valid signal, so theoretically, the noise energy in the reference audio data is relatively balanced. Therefore, the first data window can be a fixed time window, and the first window audio data only needs to be collected once.

[0075] S13: Obtaining noise energy of the audio data in the first window according to the mean square error of the audio data in the first window;

[0076] By calculating the mean square error of the first window audio data, the positive and negative characteristics of the signal in the first window audio data can be eliminated, and then the first window audio data can be concentrated to calculate the average value, which can effectively reflect the average energy level of the first window audio data; at the same time, the mean square error has a certain robustness to the noise and outliers in the first window audio data, and can effectively integrate the noise therein to reflect the overall energy level of the first window audio data.

[0077] S14: Acquire the reference noise threshold according to the noise energy.

[0078] Preferably, in this embodiment, the reference noise threshold may be set to twice the noise energy.

[0079] S2: collecting real-time audio data of the optical cable to be tested at a current sampling time point through the DAS system, and obtaining real-time energy at the current sampling time point according to the real-time audio data;

[0080] The DAS system collects the audio data by collecting audio data within a small time range each time, and then splicing the audio data collected in each time range; wherein, the small time range corresponds to a sampling time point. The sampling time point is affected by the sampling accuracy of the DAS system and also needs to be set according to the actual application scenario; the shorter the sampling time point, the higher the bandwidth of the DAS system, the wider the frequency range that can be measured, and the more scenarios it can be applied to. However, this will also increase the noise of the system and the complexity of data processing. Therefore, it is necessary to set a specific sampling time point according to the actual application scenario; in this embodiment, the sampling time point can be set to milliseconds or even microseconds.

[0081] In this embodiment, the real-time energy at the current sampling time point can be understood as the energy of the real-time audio data collected in the optical cable to be tested at the current sampling time point; specifically, the acquisition of the real-time energy can refer to the above-mentioned step of acquiring the benchmark noise threshold, and specifically may include calculating the mean square error of the real-time audio data at the current sampling time point, and acquiring the real-time energy of the real-time audio data according to the mean square error of the real-time audio data.

[0082] Meanwhile, it is understandable that the real-time audio data may contain valid signals. Therefore, in this embodiment, it is necessary to identify the valid signals in the real-time audio data.

[0083] S3: Obtaining a reference energy corresponding to the real-time audio data;

[0084] In this embodiment, the reference energy is the audio energy value within a period of time before the current sampling time point;

[0085] Therefore, if Figure 3 The acquisition of the reference energy may include the following steps:

[0086] S31: Acquire, according to a preset second data window, second window audio data within a second time range from the audio data before the current sampling time point;

[0087] In a specific implementation of this embodiment, since the real-time audio data can be considered as real-time audio data within a period of time in the optical cable to be tested, the width of the second data window can be set according to the interval between sampling time points, and then a sliding window is used with one sampling time point as the step size. As the real-time audio data is continuously acquired, the real-time audio data is slid in the real-time audio data. Before sliding to the current sampling time point, the real-time audio data contained in the second data window is intercepted each time it slides to obtain the second window audio data corresponding to the sampling time point, thereby ensuring that the second window audio data contains the latest audio data information.

[0088] At the same time, in a specific embodiment, a sampling processing cycle can be set. In each sampling processing cycle, the second window audio data collected by each sliding window is cached, and the second window audio data is processed in the cache area. Then, after the second window audio data of the current sampling processing cycle is processed, the second window audio data of the current sampling processing cycle is released, and the second window audio data of the next sampling processing cycle is obtained for cache processing, and so on, so that the second window audio data of each real-time sampling processing cycle can be processed in a timely manner, while ensuring parallel processing of data and improving processing efficiency.

[0089] S32: Calculate the mean square error of the second window audio data, and obtain the reference energy corresponding to the real-time audio data according to the mean square error of the second window audio data.

[0090] As mentioned above, the mean square error can effectively integrate the noise in the audio data. Since the second window audio data is the same as the real-time audio data, it contains both internal system noise and external environmental noise. Therefore, by calculating the mean square error of the second window audio data, the system noise and environmental noise in the second window audio data can be effectively integrated, thereby obtaining the overall energy level of the second window audio data.

[0091] Preferably, in this embodiment, the reference energy corresponding to the real-time audio data is obtained based on the mean square error of the second window audio data. Specifically, twice the mean square error of the second window audio data is used as the reference energy of the real-time audio data.

[0092] S4: updating the reference noise threshold according to the reference energy;

[0093] It is understandable that the external environmental noise in the real-time audio data is dynamic and will change with changes in the environment; therefore, in the actual application process, in order to better eliminate the influence of the noise in the real-time audio data, it is necessary to update the baseline noise threshold and introduce the influence of environmental noise into the baseline noise threshold.

[0094] Therefore, in this step, if Figure 4 As shown, the updating of the baseline noise threshold may specifically include:

[0095] S41: Comparing the reference energy with the reference noise threshold;

[0096] S42: If the reference energy is less than the reference noise threshold, setting the reference noise threshold to be equal to the reference energy;

[0097] In this embodiment, the original baseline noise threshold represents the internal system noise obtained in the absence of a valid signal, while the baseline energy is obtained by calculating the mean square error of the second window audio data, which integrates the overall situation of the internal system noise, external environmental noise, and audio energy before the current sampling time point. Therefore, when the baseline energy is less than the baseline noise threshold, it means that the real-time audio data before the current sampling time point does not contain external environmental noise and audio energy and is mainly affected by environmental noise. Therefore, the baseline noise threshold is updated to be equal to the baseline energy, taking into account the influence of the environmental noise and internal noise.

[0098] In this step, by continuously updating the baseline noise threshold, the baseline noise threshold can simultaneously reflect the influence of internal system noise and external environmental noise, so that it can be matched according to the actual environmental noise and the energy situation of the effective signal, and thus can be used more accurately to judge whether a valid signal appears.

[0099] S43: If the reference energy is greater than or equal to the reference noise threshold, keep the reference noise threshold unchanged.

[0100] In step S42, the baseline noise threshold is updated so that the baseline noise threshold can effectively reflect the internal system noise and external environmental noise. Therefore, when the baseline energy is greater than or equal to the baseline noise threshold, it can be understood that a valid signal may begin to appear in the audio data at the previous sampling time point.

[0101] It should be noted that the baseline noise threshold is equivalent to a global variable, which will be updated as time goes by, that is, the sampling time point is updated, and the baseline energy and real-time energy are real-time variables. Therefore, through the settings of the above steps S42 and S43, the baseline energy is matched with the sampling time of the baseline noise threshold, which is conducive to better capturing the time when the effective signal appears and disappears.

[0102] S5: judging whether there is a valid signal in the real-time audio data according to the real-time energy and the updated reference noise threshold;

[0103] Specifically, in this embodiment, Figure 5 As shown, the determination of the valid signal may specifically include:

[0104] S51: When the real-time energy is greater than the updated reference noise threshold, determining that there is a valid signal in the real-time audio data;

[0105] S52: When the real-time energy is less than or equal to the updated reference noise threshold, determine that no valid signal exists in the real-time audio data.

[0106] As described above, the updated baseline noise threshold integrates the influence of environmental noise and internal noise. Therefore, when the real-time energy at the current sampling time point is greater than the updated baseline noise threshold, it can be considered that the real-time energy contains valid signals in addition to the environmental noise and internal noise; otherwise, it can be considered that the real-time energy does not contain valid signals.

[0107] S6: If there is a valid signal, take the current sampling time point as the starting point of the valid signal, and amplify the real-time audio data collected after the starting point;

[0108] Specifically, in this embodiment, amplifying the real-time audio data collected after the starting point may include:

[0109] The audio data collected after the starting point is amplified according to a preset magnification. It can be understood that when the power of the audio data is amplified and the ambient noise remains unchanged, the signal-to-noise ratio of the effective signal is improved. Preferably, in this embodiment, the preset magnification can be set to 10 times; by amplifying the effective signal by 10 times, the signal-to-noise ratio can be improved by 20*lg(10)=20dB.

[0110] It is understandable that effective signals may not always be collected from the optical cable to be tested at each sampling time point, or the signal strength of the collected effective signals may be too low to be effectively analyzed.

[0111] Therefore, in this embodiment, after amplifying the real-time audio data, the following steps may also be performed:

[0112] Continue to collect real-time audio data after the starting point, and obtain corresponding reference energy according to the real-time audio data after the starting point;

[0113] further updating the updated baseline noise threshold according to the baseline energy after the starting point;

[0114] Determining whether there is a valid signal in the real-time audio data after the starting point based on the real-time energy and the further updated reference noise threshold;

[0115] If no valid signal exists, the sampling time point corresponding to the real-time audio data after the starting point is used as the end point of the valid signal, and amplification of the real-time audio data collected after the end point is stopped. The acquisition of the baseline energy and the updating of the baseline noise threshold can be performed with reference to the descriptions of steps S31-S32 and S41-S43 above, respectively. Furthermore, the determination of the end point of the valid signal can refer to the determination in step S52 above, i.e., when the real-time energy after the starting point is less than or equal to the updated baseline noise threshold, and no valid signal exists in the real-time audio data after the starting point, the corresponding sampling time point is used as the end point of the valid signal.

[0116] It should be noted that in this embodiment, the amplification of the real-time audio data is actually the amplification of the valid signal. The real-time audio data is continuously acquired. Therefore, in the process of acquiring the real-time audio data, multiple segments of valid signals may be acquired, that is, audio data between a starting point and a corresponding end point.

[0117] Therefore, stopping the amplification of the real-time audio data collected after the end point does not mean stopping the collection of the real-time audio data. On the contrary, it is necessary to continue collecting the real-time audio data, and continue to obtain the starting point and end point of the valid signal based on the real-time audio data, amplify the real-time audio data between the starting point and the end point, and achieve amplification of all valid signals.

[0118] S7: The amplified real-time audio data is used as valid audio data.

[0119] As described above, the amplified implemented audio data corresponds to the amplified effective signal. By amplifying the effective signal, the signal-to-noise ratio of the audio data is effectively improved. Furthermore, by extracting the amplified real-time audio data as effective audio data, the signal-to-noise ratio of the audio data is further improved.

[0120] This embodiment pre-collects the baseline noise threshold of the DAS system when no valid signal is present, used to determine whether the audio data in the optical cable under test is a valid signal. It then collects real-time audio data containing a valid signal, calculates the real-time energy and baseline energy of the real-time audio data, and uses the baseline energy to update the baseline noise threshold. This baseline noise threshold is then updated to include both external and internal noise at the previous sampling point. This allows for better comparison of the real-time energy with the baseline noise threshold to identify a valid signal and its starting point. Furthermore, by amplifying the valid signal, the signal-to-noise ratio is improved without altering the system noise. This method is computationally simple and does not require complex algorithms or additional hardware.

[0121] Example 2

[0122] Based on the same inventive concept as the embodiment, Figure 6 As shown, this embodiment provides an audio data acquisition system based on DAS, and the acquisition system may specifically include:

[0123] A reference threshold value acquisition module 11 is used to obtain a reference noise threshold value of the DAS system in the optical cable to be tested;

[0124] In this embodiment, the DAS system is primarily used to collect and capture the effects of acoustic waves on the optical cable under test. Therefore, the effective signal in this embodiment primarily refers to the acoustic wave signal received by the optical cable under test. To effectively extract the effective signal from the optical cable under test, it is necessary to eliminate noise from the various signals received by the optical cable under test.

[0125] In this embodiment, the reference noise threshold is the noise condition of the DAS system in the optical cable to be tested. It can be understood that the reference noise threshold represents the system noise condition generated by the DAS system itself after the DAS system is connected to the optical cable to be tested, without interference from other external factors.

[0126] Specifically, in this embodiment, obtaining the baseline noise threshold of the DAS system according to the first window audio data may include:

[0127] First, the reference audio data of the optical cable to be tested is collected through the DAS system;

[0128] In this embodiment, the reference audio data is audio data collected when there is no valid signal in the optical cable under test; that is, the audio data collected after the DAS system is connected to the optical cable under test and without interference from other external factors. Preferably, to ensure data reliability, the reference audio data can be collected over a longer period of time.

[0129] As described above, the reference noise threshold represents the noise generated inside the DAS system without interference from other external factors, and thus the reference noise threshold can be obtained through reference audio data when the optical cable to be tested contains no valid signal.

[0130] Next, according to a preset first data window, first window audio data of a preset first time range is obtained from the reference audio data;

[0131] Specifically, since the reference audio data does not contain a valid signal, theoretically, the noise energy in the reference audio data is relatively balanced. Therefore, the first data window can be a fixed time window, and the first window audio data only needs to be collected once.

[0132] Then, obtaining noise energy of the audio data in the first window according to the mean square error of the audio data in the first window;

[0133] By calculating the mean square error of the first window audio data, the positive and negative characteristics of the signal in the first window audio data can be eliminated, and then the first window audio data can be concentrated to calculate the average value, which can effectively reflect the average energy level of the first window audio data; at the same time, the mean square error has a certain robustness to the noise and outliers in the first window audio data, and can effectively integrate the noise therein to reflect the overall energy level of the first window audio data.

[0134] Finally, the reference noise threshold is obtained according to the noise energy.

[0135] Preferably, in this embodiment, the reference noise threshold may be set to twice the noise energy.

[0136] An audio data acquisition module 12 is configured to collect real-time audio data of the optical cable to be tested at a current sampling time point through a DAS system, and obtain real-time energy at the current sampling time point based on the real-time audio data;

[0137] The DAS system collects the audio data by collecting audio data within a small time range each time, and then splicing the audio data collected in each time range; wherein, the small time range corresponds to a sampling time point. The sampling time point is affected by the sampling accuracy of the DAS system and also needs to be set according to the actual application scenario; the shorter the sampling time point, the higher the bandwidth of the DAS system, the wider the frequency range that can be measured, and the more scenarios it can be applied to. However, this will also increase the noise of the system and the complexity of data processing. Therefore, it is necessary to set a specific sampling time point according to the actual application scenario; in this embodiment, the sampling time point can be set to milliseconds or even microseconds.

[0138] In this embodiment, the real-time energy at the current sampling time point can be understood as the energy of the real-time audio data collected in the optical cable to be tested at the current sampling time point; specifically, the acquisition of the real-time energy can refer to the acquisition of the above-mentioned baseline noise threshold, and specifically may include calculating the mean square error of the real-time audio data at the current sampling time point, and acquiring the real-time energy of the real-time audio data according to the mean square error of the real-time audio data.

[0139] Meanwhile, it is understandable that the real-time audio data may contain valid signals. Therefore, in this embodiment, it is necessary to identify the valid signals in the real-time audio data.

[0140] The audio energy calculation module 13 is used to obtain the reference energy corresponding to the real-time audio data;

[0141] In this embodiment, the reference energy is the audio energy value within a period of time before the current sampling time point;

[0142] Therefore, obtaining the reference energy may include:

[0143] First, according to a preset second data window, obtain second window audio data of a second time range from the audio data before the current sampling time point;

[0144] In a specific implementation of this embodiment, since the real-time audio data can be considered as real-time audio data within a period of time in the optical cable to be tested, the width of the second data window can be set according to the interval between sampling time points, and then a sliding window is used with one sampling time point as the step size. As the real-time audio data is continuously acquired, the real-time audio data is slid in the real-time audio data. Before sliding to the current sampling time point, the real-time audio data contained in the second data window is intercepted each time it slides to obtain the second window audio data corresponding to the sampling time point, thereby ensuring that the second window audio data contains the latest audio data information.

[0145] At the same time, in a specific embodiment, a sampling processing cycle can be set. In each sampling processing cycle, the second window audio data collected by each sliding window is cached, and the second window audio data is processed in the cache area. Then, after the second window audio data of the current sampling processing cycle is processed, the second window audio data of the current sampling processing cycle is released, and the second window audio data of the next sampling processing cycle is obtained for cache processing, and so on, so that the second window audio data of each real-time sampling processing cycle can be processed in a timely manner, while ensuring parallel processing of data and improving processing efficiency.

[0146] Then, the mean square error of the second window audio data is calculated, and the reference energy corresponding to the real-time audio data is obtained according to the mean square error of the second window audio data.

[0147] As mentioned above, the mean square error can effectively integrate the noise in the audio data. Since the second window audio data is the same as the real-time audio data, it contains both internal system noise and external environmental noise. Therefore, by calculating the mean square error of the second window audio data, the system noise and environmental noise in the second window audio data can be effectively integrated, thereby obtaining the overall energy level of the second window audio data.

[0148] Preferably, in this embodiment, the reference energy corresponding to the real-time audio data is obtained based on the mean square error of the second window audio data. Specifically, twice the mean square error of the second window audio data is used as the reference energy of the real-time audio data.

[0149] A noise threshold updating module 14 is configured to update the reference noise threshold according to the reference energy;

[0150] It is understandable that the external environmental noise in the real-time audio data is dynamic and will change with changes in the environment; therefore, in the actual application process, in order to better eliminate the influence of the noise in the real-time audio data, it is necessary to update the baseline noise threshold and introduce the influence of environmental noise into the baseline noise threshold.

[0151] Therefore, updating the baseline noise threshold may specifically include:

[0152] comparing the reference energy with the reference noise threshold;

[0153] If the reference energy is less than the reference noise threshold, setting the reference noise threshold to be equal to the reference energy;

[0154] In this embodiment, the original baseline noise threshold represents the internal system noise obtained in the absence of a valid signal, while the baseline energy is obtained by calculating the mean square error of the second window audio data, which integrates the overall situation of the internal system noise, external environmental noise, and audio energy before the current sampling time point. Therefore, when the baseline energy is less than the baseline noise threshold, it means that the real-time audio data before the current sampling time point does not contain external environmental noise and audio energy and is mainly affected by environmental noise. Therefore, the baseline noise threshold is updated to be equal to the baseline energy, taking into account the influence of the environmental noise and internal noise.

[0155] Specifically, by continuously updating the baseline noise threshold, the baseline noise threshold can simultaneously reflect the influence of internal system noise and external environmental noise, so that it can be matched according to the actual environmental noise and the energy situation of the effective signal, and thus can be used more accurately to judge whether a valid signal appears.

[0156] Then, if the reference energy is greater than or equal to the reference noise threshold, the reference noise threshold is kept unchanged.

[0157] Specifically, the update of the baseline noise threshold enables the baseline noise threshold to effectively reflect the internal system noise and external environmental noise. Therefore, when the baseline energy is greater than or equal to the baseline noise threshold, it can be understood that a valid signal may begin to appear in the audio data at the previous sampling time point.

[0158] a valid signal confirmation module 15, configured to determine whether there is a valid signal in the real-time audio data based on the real-time energy and the updated reference noise threshold;

[0159] Specifically, in this embodiment, the determination of the valid signal may include:

[0160] When the real-time energy is greater than the updated reference noise threshold, determining that there is a valid signal in the real-time audio data;

[0161] When the real-time energy is less than or equal to the updated reference noise threshold, it is determined that no valid signal exists in the real-time audio data.

[0162] As described above, the updated baseline noise threshold integrates the influence of environmental noise and internal noise. Therefore, when the real-time energy at the current sampling time point is greater than the updated baseline noise threshold, it can be considered that the real-time energy contains valid signals in addition to the environmental noise and internal noise; otherwise, it can be considered that the real-time energy does not contain valid signals.

[0163] If there is a valid signal, taking the current sampling time point as the starting point of the valid signal, and amplifying the real-time audio data collected after the starting point;

[0164] Specifically, in this embodiment, amplifying the real-time audio data collected after the starting point may include:

[0165] The audio data collected after the starting point is amplified according to a preset magnification. It can be understood that when the power of the audio data is amplified and the ambient noise remains unchanged, the signal-to-noise ratio of the effective signal is improved. Preferably, in this embodiment, the preset magnification can be set to 10 times; by amplifying the effective signal by 10 times, the signal-to-noise ratio can be improved by 20*lg(10)=20dB.

[0166] It is understandable that effective signals may not always be collected from the optical cable to be tested at each sampling time point, or the signal strength of the collected effective signals may be too low to be effectively analyzed.

[0167] Therefore, in this embodiment, after amplifying the real-time audio data, the following steps may also be performed:

[0168] Continue to collect real-time audio data after the starting point, and obtain corresponding reference energy according to the real-time audio data after the starting point;

[0169] further updating the updated baseline noise threshold according to the baseline energy after the starting point;

[0170] Determining whether there is a valid signal in the real-time audio data after the starting point based on the real-time energy and the further updated reference noise threshold;

[0171] If no valid signal exists, the sampling time point corresponding to the real-time audio data after the starting point is used as the end point of the valid signal, and the amplification of the real-time audio data collected after the end point is stopped. The acquisition of the baseline energy can be achieved by the audio energy calculation module 13, and the updating of the baseline noise threshold can be achieved by the noise threshold update module 14; and the determination of the valid signal can be achieved by the valid signal confirmation module 15. The determination of the end point of the valid signal can be: when the real-time energy is less than or equal to the updated baseline noise threshold, and no valid signal exists in the real-time audio data at this time, the corresponding sampling time point is used as the end point of the valid signal.

[0172] It should be noted that in this embodiment, the amplification of the real-time audio data is actually the amplification of the valid signal. The real-time audio data is continuously acquired. Therefore, in the process of acquiring the real-time audio data, multiple segments of valid signals may be acquired, that is, audio data between a starting point and a corresponding end point.

[0173] Therefore, stopping the amplification of the real-time audio data collected after the end point does not mean stopping the collection of the real-time audio data. On the contrary, it is necessary to continue collecting the real-time audio data, and continue to obtain the starting point and end point of the valid signal based on the real-time audio data, amplify the real-time audio data between the starting point and the end point, and achieve amplification of all valid signals.

[0174] The valid signal confirmation module 15 is further configured to use the amplified real-time audio data as valid audio data;

[0175] As described above, the amplified implemented audio data corresponds to the amplified effective signal. By amplifying the effective signal, the signal-to-noise ratio of the audio data is effectively improved. Furthermore, by extracting the amplified real-time audio data as effective audio data, the signal-to-noise ratio of the audio data is further improved.

[0176] Example 3

[0177] Based on the same inventive concept as in Example 1, Figure 7 As shown, this embodiment provides an electronic device, including a memory 21 and a processor 22, wherein the memory 21 stores computer-readable instructions, and the processor 22 executes the computer-readable instructions to implement the DAS-based audio data acquisition method of this embodiment.

[0178] Preferably, the electronic device further includes a bus 23 and a communication interface 24 , and the processor 22 , the communication interface 24 and the memory 21 are connected via the bus 23 .

[0179] Memory 21 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk drive. Communication between the system network element and at least one other network element is achieved via at least one communication interface 24 (which may be wired or wireless). This interface may utilize the Internet, a wide area network (WAN), a local area network (LAN), a metropolitan area network (MAN), or the like. Bus 23 may be an ISA bus, a PCI bus, or an EISA bus. Bus 23 may be divided into an address bus, a data bus, a control bus, and the like (not fully illustrated in the figure).

[0180] The processor 22 can be an integrated circuit chip with signal processing capabilities. In specific implementations, each step in the above-mentioned method embodiment can be completed by hardware integrated logic circuits or software instructions in the processor 22. The above-mentioned processor 22 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components, which can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor can be a microprocessor, or the processor 22 can also be any conventional processor 22. The steps of the method disclosed in conjunction with the embodiments of the present invention can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as a random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or register. The storage medium is located in the memory 21, and the processor 22 reads the information in the memory 21 and, in conjunction with its hardware, completes the steps of the method of the aforementioned embodiment.

[0181] An embodiment of the present invention further provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are called and executed by the processor 22, the computer-executable instructions prompt the processor 22 to implement the above-mentioned DAS-based audio data acquisition method. The specific implementation can be found in the embodiment and will not be repeated here.

[0182] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0183] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the technical solutions of the present invention, and are not intended to limit the specific implementation methods of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the claims of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A method for acquiring audio data based on DAS, characterized in that: The acquisition method includes: Obtain the baseline noise threshold of the DAS system in the optical cable under test; Collecting real-time audio data of the optical cable to be tested at a current sampling time point through a DAS system, and obtaining real-time energy at the current sampling time point based on the real-time audio data; Obtaining a reference energy corresponding to the real-time audio data; the reference energy is an audio energy value within a period of time before the current sampling time point; updating the reference noise threshold according to the reference energy; Determining whether there is a valid signal in the real-time audio data according to the real-time energy and the updated reference noise threshold; If there is a valid signal, taking the current sampling time point as the starting point of the valid signal, and amplifying the real-time audio data collected after the starting point; Using the amplified real-time audio data as valid audio data; The updating of the reference noise threshold according to the reference energy includes: comparing the reference energy with the reference noise threshold; If the reference energy is less than the reference noise threshold, setting the reference noise threshold to be equal to the reference energy; If the reference energy is greater than or equal to the reference noise threshold, the reference noise threshold is kept unchanged.

2. The DAS-based audio data acquisition method according to claim 1, characterized in that: The obtaining of the baseline noise threshold of the DAS system in the optical cable to be tested specifically includes: Collecting reference audio data of the optical cable to be tested through a DAS system; the reference audio data is audio data when there is no valid signal in the optical cable to be tested; According to a preset first data window, obtaining a first window of audio data within a preset first time range from the reference audio data; Obtaining noise energy of the audio data in the first window according to the mean square error of the audio data in the first window; The reference noise threshold is obtained according to the noise energy.

3. The DAS-based audio data acquisition method according to claim 1, characterized in that: The obtaining of the reference energy corresponding to the real-time audio data specifically includes: According to a preset second data window, obtaining second window audio data of a second time range from the audio data before the current sampling time point; Calculate the mean square error of the second window audio data, and obtain the reference energy corresponding to the real-time audio data according to the mean square error of the second window audio data.

4. The DAS-based audio data acquisition method according to claim 1, characterized in that: The determining, based on the real-time energy and the updated reference noise threshold, whether there is a valid signal in the real-time audio data specifically includes: When the real-time energy is greater than the updated reference noise threshold, determining that there is a valid signal in the real-time audio data; When the real-time energy is less than or equal to the updated reference noise threshold, it is determined that no valid signal exists in the real-time audio data.

5. The DAS-based audio data acquisition method according to any one of claims 1 to 4, characterized in that: The amplifying of the real-time audio data collected after the starting point is specifically as follows: The audio data collected after the starting point is amplified according to a preset magnification.

6. The DAS-based audio data acquisition method according to any one of claims 1 to 4, characterized in that: After amplifying the real-time audio data collected after the starting point, the method further includes: Continue to collect real-time audio data after the starting point, and obtain corresponding reference energy according to the real-time audio data after the starting point; further updating the updated baseline noise threshold according to the baseline energy after the starting point; Determining whether there is a valid signal in the real-time audio data after the starting point based on the real-time energy and the further updated reference noise threshold; If there is no valid signal, the sampling time point corresponding to the real-time audio data after the starting point is used as the end point of the valid signal, and the amplification of the real-time audio data collected after the end point is stopped.

7. A DAS-based audio data acquisition system, characterized in that: The acquisition system includes: A reference threshold acquisition module is used to obtain a reference noise threshold of the DAS system in the optical cable to be tested; An audio data acquisition module is used to collect real-time audio data of the optical cable to be tested at a current sampling time point through a DAS system, and obtain real-time energy at the current sampling time point based on the real-time audio data; An audio energy calculation module is used to obtain a reference energy corresponding to the real-time audio data; the reference energy is the audio energy value within a period of time before the current sampling time point; a noise threshold updating module, configured to update the reference noise threshold according to the reference energy; a valid signal confirmation module, configured to determine whether a valid signal exists in the real-time audio data based on the real-time energy and the updated reference noise threshold; if a valid signal exists, taking the current sampling time point as the starting point of the valid signal, amplifying the real-time audio data collected after the starting point; and using the amplified real-time audio data as the valid audio data; The updating of the reference noise threshold according to the reference energy includes: comparing the reference energy with the reference noise threshold; If the reference energy is less than the reference noise threshold, setting the reference noise threshold to be equal to the reference energy; If the reference energy is greater than or equal to the reference noise threshold, the reference noise threshold is kept unchanged.

8. The DAS-based audio data acquisition system according to claim 7, characterized in that: The obtaining of a baseline noise threshold of the DAS system in the optical cable to be tested includes: Collecting reference audio data of the optical cable to be tested through a DAS system; the reference audio data is audio data when there is no valid signal in the optical cable to be tested; According to a preset first data window, obtaining a first window of audio data within a preset first time range from the reference audio data; Obtaining noise energy of the audio data in the first window according to the mean square error of the audio data in the first window; The reference noise threshold is obtained according to the noise energy.

9. An electronic device comprising a memory and a processor, characterized in that: The memory stores computer-readable instructions, and the processor executes the computer-readable instructions to implement the DAS-based audio data acquisition method according to any one of claims 1 to 6.

10. A computer storage medium, characterized in that Computer-readable instructions are stored thereon, and when the computer-readable instructions are executed, the DAS-based audio data acquisition method according to any one of claims 1 to 6 is implemented.

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