Noise suppression method, system, wearable device, and computer-readable storage medium

Abstract

The present invention discloses a noise suppression method, system, wearable device and computer-readable storage medium, which relate to the field of electronic device control. A vibration sensor and a vibration generating device are pre-arranged on the heat dissipation module of the wearable device, replacing the microphone and speaker arranged in the airway in the prior art, to obtain the original vibration signal collected by the vibration sensor. Considering that narrowband noise presents periodic characteristics, a control signal representing the phase delay is determined based on the original vibration signal and an adaptive filtering strategy. Based on the control signal, the vibration generating device can be controlled to generate a suppressed vibration signal for counteracting the narrowband noise in the original vibration signal in an anti-phase manner. Therefore, without affecting the airway and ensuring the heat dissipation function of the heat dissipation module, the phase delay method is used to reliably and effectively achieve the anti-phase cancellation of the narrowband noise caused by the heat dissipation module when it is working, especially as its rotation speed increases, thereby greatly improving the user experience.

Description

Technical Field

[0001] The present invention relates to the field of electronic device control technology, and in particular to a noise suppression method, system, wearable device, and computer-readable storage medium. Background Art

[0002] In recent years, VR (Virtual Reality) and AR (Augmented Reality) technologies have developed rapidly and have been widely used. The functional design of products using these technologies, such as head-mounted wearable devices, has also become increasingly complex, placing a heavy workload on the main processors in the devices. Heat dissipation has become one of the primary issues to be addressed in the design.

[0003] The heat source in the device is often concentrated on the very small main chip. However, due to aesthetic requirements and size limitations, particularly large heat dissipation holes are not opened in the device or large fans are used. Usually, the number of fans is not increased to avoid causing additional troubles to the mechanical design and the overall spatial layout of the device. Therefore, the existing technology usually adopts the method of increasing the fan speed to meet the heat dissipation requirements.

[0004] However, due to the limitations of fan technology, increasing the fan speed will greatly increase the periodic narrowband noise generated during its operation. The existing technology adopts an active noise control method relying on the acoustic method in the pipeline, that is, placing the microphone and the speaker in the airway, and suppressing the noise by controlling the sound of the speaker. However, on the one hand, this method will block part of the airway and affect the heat dissipation effect; on the other hand, the airflow in the airway will impact the above-mentioned devices and generate new noise. Moreover, this method can only suppress the narrowband noise propagating from the airway to a certain extent, and cannot offset the noise radiated from the vibration source to the space outside the airway.

[0005] Therefore, how to find an effective method to suppress the narrowband noise caused by the high speed of the fan is an urgent problem to be solved. Summary of the Invention

[0006] The purpose of the present invention is to provide a noise suppression method, system, wearable device and computer-readable storage medium. On the basis of ensuring the heat dissipation function of the heat dissipation module without affecting the airway, the method and system rely on phase delay to reliably and effectively achieve the anti-phase cancellation of narrowband noise caused by the operation of the heat dissipation module, especially as its rotation speed increases, thereby greatly improving the user experience.

[0007] To solve the above technical problems, the present invention provides a noise suppression method applied to a wearable device, wherein a vibration sensor and a vibration generating device are provided on a heat dissipation module in the wearable device, and the method comprises:

[0008] Acquiring an original vibration signal collected by the vibration sensor;

[0009] Determining a control signal representing a phase delay based on the original vibration signal and the adaptive filtering strategy;

[0010] The vibration generating device is controlled based on the control signal to generate a vibration suppression signal for canceling out the narrowband noise in the original vibration signal in an anti-phase manner.

[0011] Preferably, determining a control signal representing a phase delay based on the original vibration signal and the adaptive filtering strategy includes:

[0012] The original vibration signal is superimposed with a first feedback signal to determine an error signal; the first feedback signal is obtained by passing a control signal output by an adaptive filtering algorithm through a secondary channel transfer function, wherein the secondary channel transfer function is a transfer function between the vibration generating device and the vibration sensor;

[0013] determining a reference signal based on the error signal and the control signal;

[0014] The control signal representing the phase delay is determined based on the reference signal, the error signal and the adaptive filtering algorithm.

[0015] Preferably, determining a reference signal based on the error signal and the control signal includes:

[0016] determining a second feedback signal after the control signal passes through the first estimated secondary channel transfer function;

[0017] The error signal is superimposed on the second feedback signal to determine a reference signal.

[0018] Preferably, after the original vibration signal is superimposed on the first feedback signal to determine the error signal, the method further includes:

[0019] Determining, based on the error signal and the control signal, a predicted vibration signal corresponding to a location where the preset narrowband noise energy is strongest;

[0020] determining a prediction error signal based on the predicted vibration signal and the control signal;

[0021] Accordingly, determining a reference signal based on the error signal and the control signal includes:

[0022] determining a reference signal based on the prediction error signal and the control signal;

[0023] Accordingly, determining the control signal representing the phase delay based on the reference signal, the error signal, and the adaptive filtering algorithm includes:

[0024] The control signal representing the phase delay is determined based on the reference signal, the prediction error signal and the adaptive filtering algorithm.

[0025] Preferably, determining the predicted vibration signal corresponding to the location where the preset narrowband noise energy is strongest based on the error signal and the control signal includes:

[0026] determining a third feedback signal after the control signal passes through the first estimated secondary channel transfer function;

[0027] subtracting the third feedback signal from the error signal to determine an intermediate processed signal;

[0028] The signal after the intermediate processed signal passes through the intermediate transfer function is determined to be a predicted vibration signal corresponding to the strongest point of preset narrowband noise energy, wherein the intermediate transfer function is a transfer function between the vibration sensor and the prediction error sensor.

[0029] Preferably, determining a prediction error signal based on the predicted vibration signal and the control signal includes:

[0030] determining a fourth feedback signal after the control signal passes through a second estimated secondary channel transfer function;

[0031] superimposing the predicted vibration signal on the fourth feedback signal to determine a prediction error signal;

[0032] Determining a reference signal based on the prediction error signal and the control signal includes:

[0033] determining a fifth feedback signal after the control signal passes through the second estimated secondary channel transfer function;

[0034] The prediction error signal is superimposed on the fifth feedback signal to determine a reference signal.

[0035] Preferably, determining the control signal representing the phase delay based on the reference signal, the error signal and the adaptive filtering algorithm includes:

[0036] An adaptive weight is determined based on a first preset relationship, the reference signal, and the error signal; the first preset relationship is:

[0037]

[0038] Wherein, w(n) is the adaptive weight, n is the sampling point number of the original vibration signal, μ is a preset parameter, L is the length of the secondary channel transfer function under the unit impulse response, and x(nL) represents the delayed signal corresponding to the reference signal x(n) delayed by L points; Represents the corresponding error signal delayed by L points and the corresponding transfer function e(nL) convolution between, wherein when the corresponding error signal is an error signal, the corresponding transfer function is the first estimated secondary channel transfer function; when the corresponding error signal is a predicted error signal, the corresponding transfer function is the second estimated secondary channel transfer function;

[0039] Determining, based on a second preset relationship, the adaptive weight, and the reference signal, a control signal representing a phase-delayed signal;

[0040] The second preset relationship is:

[0041] y(n)=x(n)w(n) T ;

[0042] Wherein, y(n) is the control signal.

[0043] To solve the above technical problems, the present invention further provides a noise suppression system applied to a wearable device, wherein a vibration sensor and a vibration generating device are provided on a heat dissipation module in the wearable device, and the system comprises:

[0044] A first acquisition unit, configured to acquire an original vibration signal collected by the vibration sensor;

[0045] a delayed control signal determining unit, configured to determine a control signal representing a phase delay based on the original vibration signal and an adaptive filtering strategy;

[0046] The anti-phase vibration control unit is used to control the vibration generating device based on the control signal to generate a vibration suppression signal for canceling out the narrowband noise in the original vibration signal in anti-phase.

[0047] To solve the above technical problems, the present invention further provides a wearable device, comprising:

[0048] A heat dissipation module for dissipating heat from the wearable device;

[0049] A vibration sensor and a vibration generating device are provided on the heat dissipation module;

[0050] A processor is connected to the vibration sensor and the vibration generating device respectively, and is used to execute the steps of the noise suppression method as described above.

[0051] To solve the above technical problems, the present invention further provides a computer-readable storage medium, comprising:

[0052] The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the steps of the noise suppression method described above are implemented.

[0053] The present application provides a noise suppression method, system, wearable device and computer-readable storage medium. A vibration sensor and a vibration generating device are pre-installed on the heat dissipation module of the wearable device to replace the microphone and speaker set in the airway in the prior art, and the original vibration signal collected by the vibration sensor is obtained. There is a narrowband vibration signal corresponding to the narrowband noise in the original vibration signal. Based on the periodic characteristics of the narrowband noise, a control signal representing the phase delay is determined based on the original vibration signal and an adaptive filtering strategy. Based on the control signal, the vibration generating device can be controlled to generate a suppressed vibration signal for counteracting the narrowband noise in the original vibration signal in an anti-phase manner. Therefore, without affecting the airway and ensuring the heat dissipation function of the heat dissipation module, the phase delay method is used to reliably and effectively achieve the anti-phase cancellation of the narrowband noise brought about by the heat dissipation module when it is working, especially as its rotation speed increases, thereby greatly improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the prior art and the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0055] Figure 1 A flowchart of a noise suppression method provided by the present invention;

[0056] Figure 2 A structural block diagram corresponding to an adaptive filtering strategy provided by the present invention;

[0057] Figure 3 This is a schematic diagram showing the actual noise situation of a heat dissipation module when noise suppression is not performed in the prior art;

[0058] Figure 4 A schematic diagram showing the actual noise situation of a heat dissipation module after noise suppression provided by the present invention;

[0059] Figure 5 This is another schematic diagram showing the actual noise situation of the heat dissipation module when noise suppression is not performed in the prior art;

[0060] Figure 6Another schematic diagram showing the actual noise situation of the heat dissipation module after noise suppression provided by the present invention;

[0061] Figure 7 For Figure 5 Correspondingly, another spectrum diagram of the actual noise condition of the heat dissipation module when noise suppression is not performed in the prior art;

[0062] Figure 8 For Figure 6 Correspondingly, another spectrogram of the actual noise situation of the heat dissipation module after noise suppression provided by the present invention;

[0063] Figure 9 Another structural block diagram corresponding to the adaptive filtering strategy provided by the present invention;

[0064] Figure 10 Another schematic diagram showing the actual noise situation of the heat dissipation module after noise suppression provided by the present invention;

[0065] Figure 11 For Figure 10 Correspondingly, another spectrogram of the actual noise situation of the heat dissipation module after noise suppression provided by the present invention;

[0066] Figure 12 This is a schematic diagram showing the actual noise situation collected when a heat dissipation module is working and when no noise suppression is performed in the prior art;

[0067] Figure 13 For Figure 12 Correspondingly, a schematic diagram showing the actual noise situation of another heat dissipation module provided by the present invention when it is working and after noise suppression is performed;

[0068] Figure 14 For Figure 12 Correspondingly, a spectrogram of actual noise conditions collected when a heat dissipation module is working and without noise suppression in the prior art;

[0069] Figure 15 For Figure 13 Correspondingly, a spectrogram of the actual noise situation of another heat dissipation module provided by the present invention when it is working and after noise suppression;

[0070] Figure 16 A schematic diagram showing the effect of a noise suppression method provided by the present invention;

[0071] Figure 17 This is a structural schematic diagram of a noise suppression system provided by the present invention. DETAILED DESCRIPTION

[0072] The core of the present invention is to provide a noise suppression method, system, wearable device and computer-readable storage medium. On the basis of ensuring the heat dissipation function of the heat dissipation module without affecting the airway, the method relies on phase delay to reliably and effectively achieve the anti-phase cancellation of narrowband noise caused by the heat dissipation module when it is working, especially as its rotation speed increases, greatly improving the user experience.

[0073] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0074] Please refer to Figure 1 , Figure 1 This is a flow chart of a noise suppression method provided by the present invention.

[0075] In this embodiment, considering that head-mounted wearable devices usually increase the fan speed to ensure the heat dissipation effect, the increase in speed will inevitably bring about periodic narrowband noise. The existing technology usually relies on active noise control methods using acoustic methods in the pipeline. However, on the one hand, this method blocks part of the airway, affecting heat dissipation. On the other hand, it can only suppress the narrowband noise propagating from the airway to a certain extent, and cannot offset the noise radiated from the vibration source to the space outside the airway. In order to solve the above technical problems, the present application provides a noise suppression method, which relies on the periodicity of narrowband noise to control the vibration generating device to generate a suppression vibration signal that is used to offset the narrowband noise in the original vibration signal in antiphase, thereby achieving the suppression of narrowband noise.

[0076] The noise suppression method is applied to a wearable device, wherein a vibration sensor and a vibration generating device are provided on a heat dissipation module of the wearable device. The method comprises:

[0077] S11: Acquire the original vibration signal collected by the vibration sensor;

[0078] Specifically, the wearable device includes, but is not limited to, a head-mounted wearable device, which is not specifically limited herein; the heat dissipation module includes, but is not limited to, a fan; and the vibration generating device includes, but is not limited to, a piezoelectric controller capable of generating a vibration signal. The vibration sensor can collect raw vibration signals, which are generated when the heat dissipation module is operating. Specifically, the collected raw vibration signals include narrowband vibration signals corresponding to narrowband noise. It should be noted that the narrowband noise can be single-frequency noise or a mixture of multiple frequencies, but in either case, it exhibits periodicity.

[0079] It should be noted that, as a preferred configuration, the vibration sensor may be an acceleration sensor. Of course, it may also be configured according to actual needs, and is not particularly limited here.

[0080] S12: Determine a control signal representing the phase delay based on the original vibration signal and the adaptive filtering strategy;

[0081] It is understandable that the active noise control method in the prior art described above is limited by the causal requirement of the control system (i.e., the signal processing time of the controller in the control system must be less than the propagation time of the sound vibration in space). In practice, it is found that this method can only achieve noise suppression for low-frequency noise, but it is easy for high-frequency noise to not meet the causal requirements, which leads to a significant reduction in the effectiveness of the method or even the inability to suppress high-frequency noise. The present application is based on the periodic characteristics of narrowband noise, and can generate a control signal that represents a phase delay, so that the control signal and the narrowband noise in the original vibration signal are inversely offset. Therefore, from a practical point of view, the noise suppression method provided by the present application performs relatively well in terms of both low-frequency and high-frequency noise, as shown in the figures in the subsequent embodiments.

[0082] S13: Based on the control signal, the vibration generating device is controlled to generate a vibration suppression signal for counteracting the narrowband noise in the original vibration signal in an anti-phase manner.

[0083] In addition, it should be noted that the vibration sensor can be specifically set on the casing of the heat dissipation module, such as the casing of the fan. More specifically, in order to ensure the noise suppression effect, the vibration sensor can be placed at the position where the narrowband noise energy is the strongest as much as possible in combination with the routing requirements of the various components inside the wearable device, and the vibration generator is placed in a preset area around the vibration sensor. The specific setting is based on actual needs and is not particularly limited here.

[0084] In summary, the present application provides a noise suppression method, in which a vibration sensor and a vibration generating device are pre-arranged on the heat dissipation module of the wearable device to replace the microphone and speaker arranged in the airway in the prior art; the vibration generating device is controlled to generate a suppressed vibration signal for counteracting the narrowband noise in the original vibration signal in an anti-phase manner, and then, without affecting the airway to ensure the heat dissipation function of the heat dissipation module, the phase delay method is used to reliably and effectively achieve the anti-phase cancellation of the narrowband noise brought about by the heat dissipation module when it is working, especially as its rotation speed increases, thereby greatly improving the user experience.

[0085] Based on the above embodiment:

[0086] As a preferred embodiment, based on the original vibration signal and the adaptive filtering strategy, determining the control signal representing the phase delay includes:

[0087] The original vibration signal is superimposed on the first feedback signal to determine the error signal; the first feedback signal is obtained by passing the control signal output by the adaptive filtering algorithm through the secondary channel transfer function, and the secondary channel transfer function is the transfer function between the vibration generating device and the vibration sensor;

[0088] determining a reference signal based on the error signal and the control signal;

[0089] Based on the reference signal, the error signal and the adaptive filtering algorithm, a control signal representing the phase delay is determined.

[0090] In this embodiment, the steps of determining the control signal after the phase delay are provided, as described above. It should be noted that the secondary channel transfer function can be measured in advance.

[0091] Please refer to the Figure 2 , Figure 2 The present invention provides a structural block diagram corresponding to an adaptive filtering strategy, wherein, considering that the processing of discrete signals is usually performed in the z domain, Figure 2 The secondary channel transfer function is represented by S(z). As for the specific transformation processing method of the discrete signal in the z domain, it is a common discrete signal processing method in the prior art. The embodiments of this application focus on the execution logic of signal transmission and processing results. Figure 2 As shown, the original vibration signal is represented by d(n), wherein n is the sampling point number of the original vibration signal, the first feedback signal is represented by s(n), the control signal is represented by y(n), and the reference signal is represented by x(n), wherein the reference signal x(n) essentially characterizes the vibration intensity at the location of the vibration generating device; the error signal is represented by e(n).

[0092] As a preferred embodiment, determining the reference signal based on the error signal and the control signal includes:

[0093] determining a second feedback signal after the control signal passes through the first estimated secondary channel transfer function;

[0094] The error signal is superimposed on the second feedback signal to determine the reference signal.

[0095] In this embodiment, the steps for determining the reference signal are given. For details, please refer to Figure 2 , Figure 2 The first estimated secondary channel transfer function is The second feedback signal is represented by s1(n), and the error signal e(n) is superimposed on the second feedback signal s1(n) to determine a reference signal x(n) representing the vibration intensity at the location of the vibration generating device. It should be noted that the first estimated secondary channel transfer function here essentially represents the statistical mean of the secondary channel transfer function S(z).

[0096] It should also be noted that the adaptive filtering algorithm is essentially based on the LSM algorithm (Least Mean Square, least mean square algorithm) setting, corresponding to Figure 2 , the adaptive filtering algorithm is set to consist of the following four parts, namely: Z -L The corresponding structure frame, The corresponding structure box, the structure box corresponding to the LSM algorithm and the corresponding W(z) structure box are represented (wherein the arrow with the folded line represents: the structure box corresponding to the LSM algorithm is the reference signal x(n) passing through Z -L As a result of the structure frame, the error signal e(n) is passed through The result of the structure box is used as input, and the adaptive weight is output to the W(z) structure box, and then the final control signal y(n) is determined by the corresponding W(z) structure box.

[0097] Thus, based on the above embodiment, the control signal representing the phase delay is determined based on the reference signal, the error signal and the adaptive filtering algorithm, including:

[0098] Determining an adaptive weight based on a first preset relationship, a reference signal, and an error signal;

[0099] The first preset relationship is:

[0100]

[0101] Where w(n) is the adaptive weight, n is the sampling point number of the original vibration signal d(n), μ is the preset parameter (which can be set according to actual needs), L is the length of the secondary channel transfer function S(z) under the unit impulse response, and x(nL) represents the delayed signal corresponding to the reference signal x(n) after the delay of L points (i.e., after Z -L Structural frame processing); The error signal e(n) delayed by L points and the first estimated secondary channel transfer function are represented by e(nL). The convolution between structure frame processing).

[0102] It is understandable that the number of sampling points is sufficient, so n is much larger than L. The adaptive weight determined by the first preset relationship is essentially a recursive formula, so the first term of the recursion can be set to a preset value based on actual needs. When the convolution term in the first relationship is turned on, the following first preset relationship in the discrete case can be obtained:

[0103]

[0104] Furthermore, based on the second preset relationship, the adaptive weight w(n) and the reference signal x(n), a control signal y(n) representing the phase delay can be determined;

[0105] The second preset relationship is:

[0106] y(n)=x(n)w(n) T

[0107] As an explanation of the noise suppression effect of the above embodiment, please first refer to Figure 3 , Figure 3 This is a schematic diagram showing the actual noise situation of a heat dissipation module when noise suppression is not performed in the prior art, wherein: Figure 3 The horizontal axis represents time in milliseconds; the vertical axis is dBFs; please refer to Figure 4 , Figure 4 This is a schematic diagram showing the actual noise situation of a heat dissipation module after noise suppression provided by the present invention, that is, a schematic diagram showing the noise suppression after noise suppression according to the method described in the above embodiment (here, it is assumed that the method is method 1), wherein: Figure 4 The horizontal axis represents time in milliseconds; the vertical axis is dBFs. Figure 3 and Figure 4 It can be seen that the noise is significantly suppressed.

[0108] For a clearer presentation, please refer to Figure 5 , Figure 5 This is another schematic diagram showing the actual noise situation of the heat dissipation module when noise suppression is not performed in the prior art (here is the simulation processing of composite frequency noise), where: Figure 5 The horizontal axis represents time in seconds; the vertical axis represents decibels dB; please refer to Figure 6 , Figure 6 Another schematic diagram of the present invention provides a display of the actual noise situation of the heat dissipation module after noise suppression (here is a simulation of composite frequency noise), that is, a schematic diagram of the display after noise suppression according to the method 1 described in the above embodiment, wherein: Figure 6 The horizontal axis represents time in seconds; the vertical axis is decibel dB. Figure 5 and Figure 6It can be seen that the noise is significantly suppressed. Figure 7 For Figure 5 The corresponding spectrogram in the prior art, Figure 8 For Figure 6 The corresponding spectrogram after noise suppression according to method 1 shows that method 1 can achieve good noise suppression effects for narrowband noise at different frequencies, but there is room for improvement for noise with higher frequencies.

[0109] As a preferred embodiment, after the original vibration signal is superimposed on the first feedback signal to determine the error signal, the method further includes:

[0110] Determining a predicted vibration signal corresponding to a location where the preset narrowband noise energy is strongest based on the error signal and the control signal;

[0111] determining a prediction error signal based on the predicted vibration signal and the control signal;

[0112] Accordingly, determining a reference signal based on the error signal and the control signal includes:

[0113] determining a reference signal based on the prediction error signal and the control signal;

[0114] Accordingly, based on the reference signal, the error signal and the adaptive filtering algorithm, a control signal representing the phase delay is determined, including:

[0115] Based on the reference signal, the prediction error signal and the adaptive filtering algorithm, a control signal representing the phase delay is determined.

[0116] In this embodiment, the inventors further take into account the limitations of installation convenience, and / or the routing requirements of various components of the wearable device, and / or the reuse of the vibration sensor (such as an accelerometer) in the wearable device from the perspective of economical design. The vibration sensor described in the above embodiment is often not guaranteed to be installed at the position where the narrowband noise energy is the strongest (specifically, the position can be determined in advance but it is not necessarily guaranteed that the vibration sensor can be installed at this position). Therefore, there is room for further optimization of the final noise suppression effect. To this end, it is further proposed that after determining the error signal, when a prediction error sensor is assumed to be set at the preset narrowband noise energy with the strongest energy (the prediction error sensor can be a vibration sensor), how to achieve the suppression of narrowband noise is achieved. As described above, by adding this prediction, the noise suppression can be better achieved.

[0117] It is also necessary to note that please refer to Figure 9 , Figure 9Another structural block diagram corresponding to the adaptive filtering strategy provided by the present invention, wherein it should be noted that the original vibration signal is still represented by d(n), the first feedback signal is still represented by s(n), the control signal is still represented by y(n), the reference signal is still represented by x(n), the error signal is represented by e(n), and the predicted vibration signal is represented by The prediction error signal is expressed as express.

[0118] As a preferred embodiment, determining the predicted vibration signal corresponding to the location where the preset narrowband noise energy is strongest based on the error signal and the control signal includes:

[0119] determining a third feedback signal after the control signal passes through the first estimated secondary channel transfer function;

[0120] subtracting the third feedback signal from the error signal to determine an intermediate processed signal;

[0121] The signal after the intermediate processed signal passes through the intermediate transfer function is determined to be a predicted vibration signal corresponding to the strongest point of the preset narrowband noise energy, wherein the intermediate transfer function is a transfer function between the vibration sensor and the prediction error sensor.

[0122] In this embodiment, the steps for determining the predicted vibration signal are given, as described above, corresponding to Figure 9 , considering that the processing of discrete signals is usually performed in the z domain, Figure 9 The intermediate transfer function is represented by PV(z), and the intermediate transfer function PV(z) is essentially the transfer function between the vibration sensor and the prediction error sensor, which can be measured in advance; as for the specific transformation processing method of the discrete signal in the z domain, it is a common discrete signal processing method in the prior art. The embodiments of this application focus on the execution logic of signal transmission and processing results; the intermediate processed signal is represented by express.

[0123] As a preferred embodiment, determining the prediction error signal based on the predicted vibration signal and the control signal includes:

[0124] determining a fourth feedback signal after the control signal passes through the second estimated secondary channel transfer function;

[0125] superimposing the predicted vibration signal on the fourth feedback signal to determine a prediction error signal;

[0126] Determining a reference signal based on the prediction error signal and the control signal includes:

[0127] determining a fifth feedback signal after the control signal passes through the second estimated secondary channel transfer function;

[0128] The prediction error signal is superimposed on the fifth feedback signal to determine a reference signal.

[0129] In this embodiment, the steps for determining the prediction error signal are given as described above. Specifically, Figure 9 As shown, the second estimated secondary channel transfer function is The fourth feedback signal is represented by s2(n), where it should be noted that the second estimated secondary channel transfer function It can be understood as the second secondary channel transfer function S v The statistical mean of (z) and S v (z) can be obtained in advance), and the second secondary channel transfer function S v (z) is essentially the transfer function between the vibration generating device and the prediction error sensor.

[0130] The determination of the reference signal can also rely on the second estimated secondary channel transfer function Determine a fifth feedback signal after the control signal passes through the second estimated secondary channel transfer function. In essence, the fifth feedback signal is the same as the fourth feedback signal, indicating that they are in different transmission paths. Figure 9 The fifth feedback signal is represented by s3(n), and the prediction error signal is represented by The fifth feedback signal s3 ( n ) is superimposed to determine the reference signal x ( n ) .

[0131] It should also be noted that the adaptive filtering algorithm at this time is essentially an adaptive learning algorithm that relies on the LSM algorithm. Figure 9 , the adaptive filtering algorithm is set to consist of the following four parts, namely: Z -L The corresponding structure frame; The corresponding structure box; the structure box corresponding to the LSM algorithm and the corresponding W(z) structure box are represented (wherein the arrow of the folded line represents: the structure box corresponding to the LSM algorithm is represented by the reference signal x(n) passing through Z -L The result of the structure frame, the prediction error signal go through The result is taken as input, and the adaptive weight is output to the W(z) structure box, and then the corresponding W(z) structure box determines the final control signal at this time.

[0132] So far, based on the above embodiment, based on the reference signal x(n) and the prediction error signal and an adaptive filtering algorithm to determine the control signal representing the phase delay at this time, including:

[0133] Determining an adaptive weight based on a first preset relationship, a reference signal, and an error signal;

[0134] The first preset relationship is:

[0135]

[0136] Among them, w(n) is still the adaptive weight, n is still the sampling point number of the original vibration signal d(n), μ is still the preset parameter, L is still the length of the secondary channel transfer function S(z) under the unit impulse response, and x(nL) represents the delayed signal corresponding to the reference signal x(n) determined above after being delayed by L points (i.e., after Z -L structure box results); Represents the prediction error signal e(nL) obtained after delaying point L and the second estimated secondary channel transfer function The convolution between results).

[0137] Furthermore, based on the second preset relationship, the adaptive weight w(n) determined at this time, and the reference signal x(n) determined at this time, the control signal after the phase delay of the representation at this time can be determined;

[0138] The second preset relationship is:

[0139] y(n)=x(n)w(n) T

[0140] Assuming that the method described in the above embodiment is method 2, which is an optimization of method 1, the noise suppression effect of method 2 is described below:

[0141] Please refer to the Figure 10 , Figure 10 Corresponding to Figure 5 The actual noise situation of the heat dissipation module when no noise suppression is performed (this is still the simulation processing effect display). Figure 10 Another schematic diagram of displaying the actual noise situation of the heat dissipation module after noise suppression provided by the present invention is a schematic diagram of displaying the noise situation after noise suppression according to the second method described in the above embodiment, wherein: Figure 10 The horizontal axis represents time in seconds; the vertical axis is decibel dB. Figure 5 、 Figure 6 and Figure 10 It can be seen that the noise is significantly suppressed by relying on method 2 and the noise suppression effect of method 2 is better. Figure 11 For Figure 10 The corresponding spectrogram (specifically, Figure 11 For Figure 7In the prior art, the optimization of the spectrogram without noise suppression is also performed. It can be seen that Method 2 can achieve better noise suppression effects for narrowband noise at different frequencies. Although the suppression effect is somewhat insufficient when the frequency increases, compared with Method 1, Method 1 has a long convergence time and limited convergence effect, while Method 2 has an overall significantly improved convergence effect.

[0142] For further information, please refer to Figure 12 , Figure 12 In order to collect the original vibration signal according to the actual situation, the heat dissipation module (i.e., fan) is controlled so that the heat dissipation module starts and maintains a low speed after 1 second. After 4 seconds, the speed increases compared with the previous speed. At this time, the single-frequency noise is enhanced and composite frequency noise appears. Figure 12 The horizontal axis represents time in seconds; the vertical axis represents dBFs; please refer to Figure 13 , Figure 13 is a schematic diagram of the display after noise suppression by the second method described above, and Figure 13 The horizontal axis represents time in seconds; the vertical axis represents dBFs. Figure 14 For Figure 12 The corresponding spectrogram, Figure 15 For Figure 13 The corresponding spectrogram shows that Method 2 has a better noise suppression effect. Since the noise suppression method provided by this application essentially includes adaptive learning, it can be seen that the adaptive filtering algorithm adaptively learns the initial single-frequency noise within 1 to 4 seconds. After 4 seconds, the original frequency noise is promptly enhanced but can be quickly offset. The noise of other frequencies also gradually converges and cancels out. This further proves the effectiveness of Method 2.

[0143] For further information, please refer to Figure 16 , Figure 16 This is a schematic diagram showing the effect of a noise suppression method provided by the present invention, wherein the horizontal axis represents frequency; the vertical axis represents decibels (dB), the dotted line represents before noise suppression, and the solid line represents after noise suppression. This further proves that the narrowband noise is indeed well suppressed before and after the treatment, verifying the effectiveness of the noise suppression method provided by the present application.

[0144] As a preferred embodiment, determining a control signal representing a phase delay based on a reference signal, an error signal, and an adaptive filtering algorithm includes:

[0145] Determining an adaptive weight based on a first preset relationship, a reference signal, and an error signal;

[0146] The first preset relationship is:

[0147]

[0148] Where w(n) is the adaptive weight, n is the sampling point number of the original vibration signal, μ is the preset parameter, L is the length of the secondary channel transfer function under the unit impulse response, and x(nL) represents the delayed signal corresponding to the reference signal x(n) delayed by L points. Represents the corresponding error signal delayed by L points and the corresponding transfer function e(nL) Convolution between, wherein, when the corresponding error signal is an error signal, the corresponding transfer function is the first estimated secondary channel transfer function; when the corresponding error signal is a predicted error signal, the corresponding transfer function is the second estimated secondary channel transfer function;

[0149] Determining a control signal representing a phase-delayed signal based on a second preset relationship, an adaptive weight, and a reference signal;

[0150] The second preset relationship is:

[0151] y(n)=x(n)w(n) T ;

[0152] Among them, y(n) is the control signal.

[0153] The description of this part of the embodiment has been explained in the above embodiment part and will not be repeated here.

[0154] Please refer to Figure 17 , Figure 17 This is a structural schematic diagram of a noise suppression system provided by the present invention.

[0155] The noise suppression system is applied to a wearable device. A vibration sensor and a vibration generating device are provided on a heat dissipation module in the wearable device. The system includes:

[0156] A first acquisition unit 21 is used to acquire an original vibration signal collected by a vibration sensor;

[0157] A delayed control signal determining unit 22 is configured to determine a control signal representing a phase delay based on the original vibration signal and an adaptive filtering strategy;

[0158] The anti-phase vibration control unit 23 is used to control the vibration generating device based on the control signal to generate a suppression vibration signal for canceling out the narrow-band noise in the original vibration signal in anti-phase.

[0159] As a preferred embodiment, the delay control signal determining unit 22 specifically includes:

[0160] an error signal determination unit, configured to superimpose a first feedback signal on the original vibration signal to determine an error signal; the first feedback signal is a control signal output by an adaptive filtering algorithm and obtained by passing it through a secondary channel transfer function, wherein the secondary channel transfer function is a transfer function between the vibration generating device and the vibration sensor;

[0161] a reference signal determining unit, configured to determine a reference signal based on the error signal and the control signal;

[0162] The first determining unit is configured to determine the control signal representing the phase delay based on the reference signal, the error signal, and the adaptive filtering algorithm.

[0163] As a preferred embodiment, the reference signal determination unit includes:

[0164] a second feedback signal determining unit, configured to determine a second feedback signal after the control signal passes through the first estimated secondary channel transfer function;

[0165] The second determining unit is configured to superimpose the error signal on the second feedback signal to determine a reference signal.

[0166] As a preferred embodiment, the noise suppression system further includes:

[0167] a predicted vibration signal determining unit, configured to determine, after the error signal determining unit, a predicted vibration signal corresponding to a location where the preset narrowband noise energy is strongest based on the error signal and the control signal;

[0168] a prediction error signal determining unit, configured to determine a prediction error signal based on the predicted vibration signal and the control signal;

[0169] Accordingly, the reference signal determination unit is specifically configured to determine a reference signal based on the prediction error signal and the control signal;

[0170] Correspondingly, the first determination unit is specifically configured to determine the control signal representing the phase delay based on the reference signal, the prediction error signal, and the adaptive filtering algorithm.

[0171] As a preferred embodiment, the predicted vibration signal determination unit specifically includes:

[0172] a third feedback signal determining unit, configured to determine a third feedback signal after the control signal passes through the first estimated secondary channel transfer function;

[0173] an intermediate processing signal determining unit, configured to subtract the third feedback signal from the error signal to determine an intermediate processing signal;

[0174] The third determining unit is configured to determine that a signal obtained by passing the intermediate processed signal through an intermediate transfer function is a predicted vibration signal corresponding to a location where the preset narrowband noise energy is strongest, wherein the intermediate transfer function is a transfer function between the vibration sensor and the prediction error sensor.

[0175] As a preferred embodiment, the prediction error signal determining unit specifically includes:

[0176] a fourth feedback signal determining unit, configured to determine a fourth feedback signal after the control signal passes through the second estimated secondary channel transfer function;

[0177] a fourth determining unit, configured to superimpose the predicted vibration signal on the fourth feedback signal to determine a prediction error signal;

[0178] The reference signal determination unit specifically includes:

[0179] a fifth feedback signal determining unit, configured to determine a fifth feedback signal after the control signal passes through the second estimated secondary channel transfer function;

[0180] The fifth determining unit is configured to superimpose the prediction error signal on the fifth feedback signal to determine a reference signal.

[0181] As a preferred embodiment, the first determining unit specifically includes:

[0182] an adaptive weight determination unit, configured to determine an adaptive weight based on a first preset relationship, the reference signal, and the error signal;

[0183] The first preset relationship is:

[0184]

[0185] Wherein, w(n) is the adaptive weight, n is the sampling point number of the original vibration signal, μ is a preset parameter, L is the length of the secondary channel transfer function under the unit impulse response, and x(nL) represents the delayed signal corresponding to the reference signal x(n) delayed by L points; Represents the corresponding error signal delayed by L points and the corresponding transfer function e(nL) convolution between, wherein when the corresponding error signal is an error signal, the corresponding transfer function is the first estimated secondary channel transfer function; when the corresponding error signal is a predicted error signal, the corresponding transfer function is the second estimated secondary channel transfer function;

[0186] a sixth determining unit, configured to determine, based on a second preset relationship, the adaptive weight, and the reference signal, a control signal representing the phase-delayed control signal;

[0187] The second preset relationship is:

[0188] y(n)=x(n)w(n) T ;

[0189] Wherein, y(n) is the control signal.

[0190] The present invention also provides a wearable device, comprising:

[0191] Heat dissipation module for wearable devices;

[0192] A vibration sensor and a vibration generating device are provided on the heat dissipation module;

[0193] The processor is connected to the vibration sensor and the vibration generating device respectively, and is used to execute the steps of the noise suppression method as described above.

[0194] For an introduction to the wearable device provided in the present invention, please refer to the embodiment of the noise suppression method described above, which will not be repeated here.

[0195] The present invention also provides a computer-readable storage medium, comprising:

[0196] A computer program is stored on a computer-readable storage medium, and when the computer program is executed by a processor, the steps of the noise suppression method described above are implemented.

[0197] For an introduction to the computer-readable storage medium provided in the present invention, please refer to the embodiment of the noise suppression method described above, which will not be described in detail here.

[0198] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can be referred to each other. Relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements limited by the sentence "comprising a..." do not exclude the presence of other identical elements in the process, method, article or equipment including the elements.

[0199] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. The above description of the disclosed embodiments enables professionals and technicians in this field to implement or use the present invention. Various modifications to these embodiments will be obvious to professionals and technicians in this field, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A noise suppression method, characterized in that: Applied to a wearable device, a heat dissipation module in the wearable device is provided with a vibration sensor and a vibration generating device, and the method includes: Acquiring an original vibration signal collected by the vibration sensor; Determining a control signal representing a phase delay based on the original vibration signal and the adaptive filtering strategy; controlling the vibration generating device to generate a vibration suppression signal for counteracting the narrowband noise in the original vibration signal in an anti-phase manner based on the control signal; Determining a control signal representing a phase delay based on the original vibration signal and the adaptive filtering strategy includes: The original vibration signal is superimposed with a first feedback signal to determine an error signal; the first feedback signal is obtained by passing a control signal output by an adaptive filtering algorithm through a secondary channel transfer function, wherein the secondary channel transfer function is a transfer function between the vibration generating device and the vibration sensor; determining a reference signal based on the error signal and the control signal; Determining the control signal representing the phase delay based on the reference signal, the error signal and the adaptive filtering algorithm; Determining the control signal representing the phase delay based on the reference signal, the error signal, and the adaptive filtering algorithm includes: Determining an adaptive weight based on a first preset relationship, the reference signal, and the error signal; The first preset relationship is: ； in, is the adaptive weight, n is the sampling point number of the original vibration signal, is a preset parameter, L is the length of the secondary channel transfer function under the unit impulse response, represents the delayed signal corresponding to the reference signal x(n) after being delayed by L points; Indicates the error signal obtained after the delay L point And the corresponding transfer function convolution between, wherein when the corresponding error signal is an error signal, the corresponding transfer function is a first estimated secondary channel transfer function; when the corresponding error signal is a predicted error signal, the corresponding transfer function is a second estimated secondary channel transfer function; Determining, based on a second preset relationship, the adaptive weight, and the reference signal, a control signal representing a phase-delayed signal; The second preset relationship is: ； Wherein, y(n) is the control signal.

2. The noise suppression method according to claim 1, wherein: Determining a reference signal based on the error signal and the control signal includes: determining a second feedback signal after the control signal passes through the first estimated secondary channel transfer function; The error signal is superimposed on the second feedback signal to determine a reference signal.

3. The noise suppression method according to claim 1, wherein: After the original vibration signal is superimposed on the first feedback signal to determine the error signal, the method further includes: Determining, based on the error signal and the control signal, a predicted vibration signal corresponding to a location where the preset narrowband noise energy is strongest; determining a prediction error signal based on the predicted vibration signal and the control signal; Accordingly, determining a reference signal based on the error signal and the control signal includes: determining a reference signal based on the prediction error signal and the control signal; Accordingly, determining the control signal representing the phase delay based on the reference signal, the error signal, and the adaptive filtering algorithm includes: The control signal representing the phase delay is determined based on the reference signal, the prediction error signal and the adaptive filtering algorithm.

4. The noise suppression method according to claim 3, wherein: Determining, based on the error signal and the control signal, a predicted vibration signal corresponding to a location where the preset narrowband noise energy is strongest, comprising: determining a third feedback signal after the control signal passes through the first estimated secondary channel transfer function; subtracting the third feedback signal from the error signal to determine an intermediate processed signal; The signal after the intermediate processed signal passes through the intermediate transfer function is determined to be a predicted vibration signal corresponding to the strongest point of preset narrowband noise energy, wherein the intermediate transfer function is a transfer function between the vibration sensor and the prediction error sensor.

5. The noise suppression method according to claim 3, wherein: Determining a prediction error signal based on the predicted vibration signal and the control signal includes: determining a fourth feedback signal after the control signal passes through the second estimated secondary channel transfer function; superimposing the predicted vibration signal on the fourth feedback signal to determine a prediction error signal; Determining a reference signal based on the prediction error signal and the control signal includes: determining a fifth feedback signal after the control signal passes through the second estimated secondary channel transfer function; The prediction error signal is superimposed on the fifth feedback signal to determine a reference signal.

6. A noise suppression system, characterized in that: Applied to a wearable device, a heat dissipation module in the wearable device is provided with a vibration sensor and a vibration generating device, and the system includes: A first acquisition unit, configured to acquire an original vibration signal collected by the vibration sensor; a delayed control signal determining unit, configured to determine a control signal representing a phase delay based on the original vibration signal and an adaptive filtering strategy; an anti-phase vibration control unit, configured to control the vibration generating device based on the control signal to generate a vibration suppression signal for canceling out the narrowband noise in the original vibration signal in anti-phase; The delay control signal determining unit specifically includes: an error signal determination unit, configured to superimpose a first feedback signal on the original vibration signal to determine an error signal; the first feedback signal is a control signal output by an adaptive filtering algorithm and obtained by passing it through a secondary channel transfer function, wherein the secondary channel transfer function is a transfer function between the vibration generating device and the vibration sensor; a reference signal determining unit, configured to determine a reference signal based on the error signal and the control signal; A first determining unit is configured to determine the control signal representing the phase delay based on the reference signal, the error signal, and the adaptive filtering algorithm; The first determining unit specifically includes: an adaptive weight determination unit, configured to determine an adaptive weight based on a first preset relationship, the reference signal, and the error signal; The first preset relationship is: ； in, is the adaptive weight, n is the sampling point number of the original vibration signal, is a preset parameter, L is the length of the secondary channel transfer function under the unit impulse response, represents the delayed signal corresponding to the reference signal x(n) after being delayed by L points; Indicates the error signal obtained after the delay L point And the corresponding transfer function convolution between, wherein when the corresponding error signal is an error signal, the corresponding transfer function is a first estimated secondary channel transfer function; when the corresponding error signal is a predicted error signal, the corresponding transfer function is a second estimated secondary channel transfer function; a sixth determining unit, configured to determine, based on a second preset relationship, the adaptive weight, and the reference signal, a control signal representing the phase-delayed control signal; The second preset relationship is: ； Wherein, y(n) is the control signal.

7. A wearable device, characterized in that: include: A heat dissipation module for dissipating heat from the wearable device; A vibration sensor and a vibration generating device are provided on the heat dissipation module; A processor is connected to the vibration sensor and the vibration generating device respectively, and is used to execute the steps of the noise suppression method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that include: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the noise suppression method according to any one of claims 1 to 5 are implemented.

Images