Loudspeaker howling adaptive adjustment method, system, device and storage medium

Abstract

The application discloses a loudspeaker howling self-adaptive adjusting method, system and device and a storage medium, and relates to the technical field of howling suppression. The first audio signal and the second audio signal are respectively collected in real time through the first receiving antenna and the second receiving antenna, the first receiving antenna is arranged on one side of the loudspeaker and the enhancement direction thereof is the same as the radiation direction of the loudspeaker, the second receiving antenna is arranged opposite to the first receiving antenna and the enhancement direction thereof is opposite to the enhancement direction of the first receiving antenna, then the signal source position is automatically identified according to the first signal strength of the first audio signal and the second signal strength of the second audio signal, the feedback suppression configuration parameters including the suppressor switch, the feedback threshold and the filter parameters are determined according to the signal source position, and the sound feedback suppression control is performed on the first audio signal or the second audio signal according to the feedback suppression configuration parameters, so that the original sound output effect is self-adaptively improved, and the convenience of sound feedback adjustment is improved.

Description

Technical Field

[0001] This invention relates to the field of howling suppression technology, and in particular to an adaptive adjustment method, system, device and storage medium for loudspeaker howling. Background Technology

[0002] In a sound reinforcement system, if the sound output power or microphone volume is significantly increased, the sound emitted by the amplifier may directly or indirectly enter the microphone, creating positive feedback in the entire system. This can cause excessive volume at certain frequencies, resulting in howling. This phenomenon is called acoustic feedback, also known as sound feedback. Acoustic feedback not only degrades sound quality but also limits the microphone's volume, preventing accurate reproduction of the picked-up sound. Deep acoustic feedback can also cause excessively strong system signals, potentially burning out amplifiers or speakers and causing damage. Therefore, acoustic feedback in a sound reinforcement system must be suppressed.

[0003] A feedback suppressor is an automatic feedback point device that detects and calculates the frequency and attenuation of acoustic feedback when it occurs, and then executes a command to suppress the feedback based on the calculation results. Currently, feedback suppressors are standalone modules that need to be combined with a sound reinforcement system to be used. Furthermore, in combination with other systems, the parameters of the feedback suppressor are often configured to be relatively heavy to minimize feedback from the sound reinforcement system, which can lead to significant loss of the original sound. If the user moves around while using a wireless microphone, they need to manually switch between light, medium, and heavy suppression parameters, and this requires a professional technician to perform the parameter switching or adjustment, making it inconvenient to use. Summary of the Invention

[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a method, system, device, and storage medium for adaptive adjustment of loudspeaker feedback, which can perform adaptive acoustic feedback adjustment when the microphone position changes, improve the output effect of the original sound in acoustic feedback adjustment, and enhance the convenience of acoustic feedback adjustment.

[0005] On one hand, embodiments of the present invention provide an adaptive adjustment method for loudspeaker howling, comprising the following steps:

[0006] A first audio signal is acquired through a first receiving antenna, and a second audio signal is acquired through a second receiving antenna. The first receiving antenna is disposed on one side of the loudspeaker and its enhancement direction is the same as the radiation direction of the loudspeaker. The second receiving antenna is disposed opposite to the first receiving antenna and its enhancement direction is opposite to that of the first receiving antenna.

[0007] The signal source location is determined based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and feedback suppression configuration parameters are determined based on the signal source location, wherein the feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters;

[0008] The first audio signal or the second audio signal is subjected to acoustic feedback suppression control according to the feedback suppression configuration parameters.

[0009] According to some embodiments of the present invention, before the step of determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, the loudspeaker feedback adaptive adjustment method further includes the following steps:

[0010] The first multipath interference value of the first audio signal and the second multipath interference value of the second audio signal are compared with the multipath interference threshold respectively. If the first multipath interference value or the second multipath interference value is greater than the multipath interference threshold, the signal source position is not updated.

[0011] The first noise value of the first audio signal and the second noise value of the second audio signal are compared with a noise threshold. If the first noise value or the second noise value is greater than the noise threshold, the signal source position is not updated.

[0012] According to some embodiments of the present invention, determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, includes the following steps:

[0013] When the first signal strength is less than the second signal strength, and the difference between the first signal strength and the second signal strength is greater than the first strength threshold, the signal source location is determined to be the back of the loudspeaker.

[0014] When the signal source is located behind the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is determined to be off; or the suppressor switch in the feedback suppression configuration parameters is determined to be on, and the feedback threshold and filtering parameters are configured to suppress the degree of acoustic feedback weakness.

[0015] According to some embodiments of the present invention, determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, includes the following steps:

[0016] When the second signal strength is less than the first signal strength, and the difference between the second signal strength and the first signal strength is greater than the first strength threshold, and the first signal strength is less than the second strength threshold, then the signal source location is determined to be within the feedback range in front of the loudspeaker.

[0017] When the signal source is located within the feedback range in front of the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is set to "on", and the feedback threshold and filtering parameters are configured to suppress the intensity of acoustic feedback.

[0018] According to some embodiments of the present invention, determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, includes the following steps:

[0019] When the difference between the second signal strength and the first signal strength is less than the first strength threshold, the signal source location is determined to be the side of the loudspeaker;

[0020] When the signal source is located within the feedback range of the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is set to "on", and the feedback threshold and filtering parameters are configured for moderate acoustic feedback suppression.

[0021] According to some embodiments of the present invention, the acoustic feedback suppression control of the first audio signal or the second audio signal according to the feedback suppression configuration parameters includes the following steps:

[0022] The suppression circuit is controlled to be turned on or off according to the suppressor switch in the feedback suppression configuration parameters. When the suppression circuit is off, the first audio signal or the second audio signal is directly output. When the suppression circuit is on, the suppression circuit is controlled according to the feedback threshold and filtering parameters in the feedback suppression configuration parameters to suppress the first audio signal or the second audio signal.

[0023] According to some embodiments of the present invention, controlling the suppression circuit according to the feedback threshold and filtering parameters in the feedback suppression configuration parameters to perform feedback suppression on the first audio signal or the second audio signal includes the following steps:

[0024] Perform a Fourier transform on the first audio signal or the second audio signal after analog-to-digital conversion to obtain the amplitude information of each frequency point;

[0025] The frequency point amplitude information is compared with the feedback threshold, and frequency points with frequency point amplitude information greater than the feedback threshold are selected. The selected frequency points are then further filtered according to the number of notch filters in the feedback suppression configuration parameters.

[0026] The notch filter is set according to the filtering parameters, and the frequency points of the first audio signal or the second audio signal after secondary screening are filtered according to the notch filter.

[0027] On the other hand, embodiments of the present invention also provide a loudspeaker feedback adaptive adjustment system, comprising:

[0028] The first module is used to acquire a first audio signal through a first receiving antenna and acquire a second audio signal through a second receiving antenna. The first receiving antenna is disposed on one side of the loudspeaker and the enhancement direction of the first receiving antenna is the same as the radiation direction of the loudspeaker. The second receiving antenna is disposed opposite to the first receiving antenna and the enhancement direction of the second receiving antenna is opposite to the enhancement direction of the first receiving antenna.

[0029] The second module is used to determine the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and to determine feedback suppression configuration parameters based on the signal source location, wherein the feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters;

[0030] The third module is used to perform acoustic feedback suppression control on the first audio signal or the second audio signal according to the feedback suppression configuration parameters.

[0031] On the other hand, embodiments of the present invention also provide a loudspeaker feedback adaptive adjustment device, comprising:

[0032] At least one processor;

[0033] At least one memory for storing at least one program;

[0034] When the at least one program is executed by the at least one processor, the at least one processor implements the loudspeaker howling adaptive adjustment method as described above.

[0035] On the other hand, embodiments of the present invention also provide a computer-readable storage medium storing computer-executable instructions for causing a computer to perform the loudspeaker howling adaptive adjustment method as described above.

[0036] The above-described technical solution of the present invention has at least one of the following advantages or beneficial effects: A first audio signal is acquired in real time via a first receiving antenna, and a second audio signal is acquired in real time via a second receiving antenna. The first receiving antenna is positioned on one side of the loudspeaker, and its enhancement direction is the same as the loudspeaker's radiation direction. The second receiving antenna is positioned opposite to the first receiving antenna, and its enhancement direction is opposite to the first receiving antenna's enhancement direction. Then, based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, the signal source location can be determined. Based on the signal source location, appropriate feedback suppression configuration parameters, including a suppressor switch, a feedback threshold, and filtering parameters, are determined. Then, based on the feedback suppression configuration parameters, acoustic feedback suppression control is applied to either the first or second audio signal. Thus, when the microphone position changes, the signal source location can be automatically identified, and appropriate feedback suppression configuration parameters can be determined to improve the output effect of the original sound during acoustic feedback adjustment, thereby enhancing the convenience of acoustic feedback adjustment. Attached Figure Description

[0037] Figure 1 This is a flowchart of the loudspeaker feedback adaptive adjustment method provided in an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the loudspeaker system circuit provided in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the layout of the first and second receiving antennas of the loudspeaker system provided in an embodiment of the present invention;

[0040] Figure 4 This is a circuit diagram of the acoustic feedback suppression module provided in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the amplitude-frequency characteristics of the notch filter algorithm provided in an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the loudspeaker howling adaptive adjustment device provided in an embodiment of the present invention. Detailed Implementation

[0043] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar originals or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0045] In the description of this invention, the use of terms such as "first," "second," etc., is merely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated.

[0046] This invention provides an adaptive adjustment method for loudspeaker howling, which can be applied to loudspeaker systems (e.g., speakers). (Refer to...) Figure 2 The loudspeaker system includes a loudspeaker, a first receiving antenna, a second receiving antenna, a signal source location analysis module, an analog-to-digital converter module, an acoustic feedback suppression module, a digital-to-analog converter module, and a power amplifier. (Refer to...) Figure 3 The first receiving antenna 101 is disposed on one side of the loudspeaker 103, and the enhancement direction of the first receiving antenna is the same as the radiation direction of the loudspeaker. The second receiving antenna 102 is disposed opposite to the first receiving antenna, and the enhancement direction of the second receiving antenna is opposite to the enhancement direction of the first receiving antenna. Both the first and second receiving antennas are used to receive wireless audio signals emitted by a microphone (e.g., a microphone). The analog-to-digital converter module is used to convert the audio analog signals received by the receiving antennas into audio digital signals. The acoustic feedback suppression module is used to perform acoustic feedback suppression processing on the audio digital signals. The analog-to-digital converter module is used to convert the audio digital signals after acoustic feedback suppression processing into audio analog signals. The power amplifier is used to amplify the audio analog signals and output them to the loudspeaker. The signal source location analysis module is used to perform signal strength analysis based on the audio analog signals received by the dual receiving antennas to determine the signal source location (i.e., the microphone location), and send the signal source location to the acoustic feedback suppression module so that the acoustic feedback suppression module processes the input audio digital signals according to the feedback suppression configuration parameters corresponding to the signal source location.

[0047] Furthermore, the sound reinforcement system also includes a power supply module and a storage module. The power supply module is used to power the acoustic feedback suppression module, and the storage module is used to provide the acoustic feedback suppression module with feedback suppression configuration parameters corresponding to the signal source location.

[0048] It is understandable that, such as Figure 3The first and second receiving antennas shown are only for illustrating their relative position and direction to the loudspeaker; the actual first and second receiving antennas should be mounted on or inside the enclosure. Figure 3 The position of the loudspeaker shown is merely illustrative. The loudspeaker can also be located at the top, bottom, left, right, or rear of the enclosure. Accordingly, the position and orientation of the first and second receiving antennas change with the direction and position of the loudspeaker.

[0049] It is understandable that, such as Figure 2 The amplifier system circuit shown is merely an example. If the final audio signal output by the amplifier system is a digital signal, then the circuit after the acoustic feedback suppression module may not need to include a digital-to-analog conversion module.

[0050] Reference Figure 1 This invention provides an adaptive adjustment method for the howling of a first receiving antenna and a second receiving antenna amplifier, including but not limited to the following steps:

[0051] Step S110: Acquire a first audio signal through a first receiving antenna and acquire a second audio signal through a second receiving antenna. The first receiving antenna is disposed on one side of the loudspeaker and its enhancement direction is the same as the radiation direction of the loudspeaker. The second receiving antenna is disposed opposite to the first receiving antenna and its enhancement direction is opposite to that of the first receiving antenna.

[0052] Step S120: Determine the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determine the feedback suppression configuration parameters based on the signal source location. The feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters.

[0053] Step S130: Perform acoustic feedback suppression control on the first audio signal or the second audio signal according to the feedback suppression configuration parameters.

[0054] In some embodiments of step S110, the microphone acquires an analog signal, modulates the signal, and transmits it via a wireless transmitting antenna. The microphone's wireless transmitting antenna can be an omnidirectional antenna. Both the first and second receiving antennas are directional antennas. As an example, the first receiving antenna 101 and the second receiving antenna 102 are as follows... Figure 3 As shown, the first receiving antenna is installed at the front of the enclosure, just like the loudspeaker 103. The first receiving antenna enhances the signal on the right side and significantly attenuates the signal on the left side. The second receiving antenna is located at the back of the enclosure. The second receiving antenna enhances the signal on the left side and significantly attenuates the signal on the right side.

[0055] Furthermore, after the first and second receiving antennas each receive the audio analog signal, they can transmit the audio analog signal to the analog-to-digital conversion module for analog-to-digital conversion, and then input it to the acoustic feedback suppression module for processing.

[0056] In some embodiments of step S120, comparing the first signal strength of the first audio signal and the second signal strength of the second audio signal with a threshold judgment can determine the signal source location, which includes the signal source distance and signal source direction. The feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters. Further, the feedback suppressor in this embodiment can be implemented using EQ, frequency conversion, or a notch filter feedback suppression algorithm (hereinafter referred to as the notch filter algorithm). Taking the notch filter algorithm as an example, the feedback suppression configuration parameters include a feedback threshold and filtering parameters, where the filtering parameters include the number of notches, maximum attenuation depth, attenuation depth step, bandwidth (q-value), and sensitivity.

[0057] by Figure 5 Taking the amplitude-frequency response diagram of a notch filter as an example, and assuming point A is the amplitude 0dB point, the feedback suppression configuration parameters are explained in detail below:

[0058] Notch filter switch (Fon): A soft switch for the notch filter algorithm; 1 for off, 0 for on.

[0059] Notch Count (Fn): The maximum number of notches;

[0060] Maximum attenuation depth (FLim): The maximum attenuation value in dB at point C;

[0061] Attenuation depth step (Fstep): Attenuation step dB value;

[0062] Feedback threshold (FLev): The lowest dB value of the audio signal that the notch filter algorithm enables;

[0063] Bandwidth (q value) (Fq): The frequency difference between E and D, using octaves.

[0064] In this embodiment of the invention, four different acoustic feedback suppression configuration parameters with varying degrees of suppression can be pre-stored in the storage module, as follows:

[0065] The feedback suppression configuration parameters for weak acoustic feedback suppression are: Fon=1, Fn=1, FLim=9dB, Fstep=3dB, FLev=-65dB, Fq=1 / 70oct;

[0066] The feedback suppression configuration parameters for moderate acoustic feedback suppression are: Fon = 1, Fn = 3, FLim = 27dB, Fstep = 3dB, FLev = -70dB, Fq = 1 / 70oct;

[0067] The feedback suppression configuration parameters for acoustic feedback intensity suppression are: Fon = 1, Fn = 6, FLim = 27dB, Fstep = 3dB, FLev = -75dB, Fq = 1 / 70oct;

[0068] The feedback suppression configuration parameter for turning off acoustic feedback suppression is: Fon = 0.

[0069] It is understood that the above-mentioned feedback suppression configuration parameters with different levels of acoustic feedback suppression are merely illustrative. The storage module may also store more or fewer feedback suppression configuration parameters with different levels of acoustic feedback suppression in advance, and the specific values ​​in the feedback suppression configuration parameters with different levels of feedback suppression may also be adjusted appropriately according to actual needs.

[0070] In some embodiments of step S130, either the first audio signal or the second audio signal can be input to the acoustic feedback suppression module for acoustic feedback suppression control. The circuit structure of the acoustic feedback suppression module is as follows: Figure 4 As shown, the acoustic feedback suppression module includes an input terminal, a suppression circuit switch, a suppression circuit, and a control processing unit (not shown in the figure). One end of the suppression circuit switch is connected to the input terminal, and the other end can be connected to the suppression circuit or directly to the output terminal of the acoustic feedback suppression module. The suppression circuit includes a Fourier transform unit, a feedback howling frequency detection unit, and a notch filter unit (notch filter) connected in sequence. The Fourier transform unit is used to convert the time-domain signal into a frequency-domain signal; the feedback howling frequency detection unit is used to detect the frequency points in the frequency-domain signal where howling occurs; the notch filter unit is used to filter the frequency points where howling occurs. The control processing unit is used to control the suppression circuit switch and configure the parameters of the suppression circuit according to the feedback suppression configuration parameters.

[0071] According to some embodiments of the present invention, before step S120, the loudspeaker howling adaptive adjustment method of the present invention further includes, but is not limited to, the following steps:

[0072] Step S210: Compare the first multipath interference value of the first audio signal and the second multipath interference value of the second audio signal with the multipath interference threshold respectively. If the first multipath interference value or the second multipath interference value is greater than the multipath interference threshold, the signal source position is not updated.

[0073] Step S220: Compare the first noise value of the first audio signal and the second noise value of the second audio signal with a noise threshold respectively. If the first noise value or the second noise value is greater than the noise threshold, the signal source position is not updated.

[0074] In this embodiment, since the determination of the signal source orientation and distance is mainly based on the intensity of the "direct signal", and multipath interference is a reflected signal, not a direct signal, it will affect the indication of the true signal intensity. At the same time, when there are many nearby wireless interference sources, it will also cause the noise signal to increase, affecting the indication of the true signal intensity.

[0075] Based on this, please continue with the parameters Figure 2 , the signal source position analysis module can obtain the first audio signal from the first antenna and the second audio signal from the second receiving antenna through communication lines such as I2C. The signal source position analysis module analyzes the first audio signal to obtain the first signal intensity L1, the first multipath interference value P1, and the first noise value N1 of the first audio signal, and analyzes the second audio signal to obtain the second signal intensity L2, the second multipath interference value P2, and the second noise value N2 of the second audio signal. By presetting the multipath interference threshold P' and the noise threshold N', the multipath interference signal and the noise signal are filtered. That is, when P1 < P', P2 < P', N1 < N', and N2 < N' are all satisfied, it indicates that the multipath interference and noise conditions in the first audio signal and the second audio signal are not serious, and then the signal source position can be further updated by the signal intensities of the current first audio signal and the second audio signal; when P1 > P' or P2 > P' or N1 > N' or N2 > N', it indicates that the multipath interference and noise conditions in the first audio signal or the second audio signal are serious, and the signal source position is not updated based on the signal intensities of the current first audio signal and the second audio signal. Instead, the signal source position at the previous moment is still used for subsequent acoustic feedback suppression control, and the first audio signal and the second audio signal are continuously collected until the multipath interference values and noise values of the first audio signal and the second audio signal meet the above conditions and then the signal source position is updated.

[0076] According to some embodiments of the present invention, in step S120, the step of determining the signal source position according to the first signal intensity of the first audio signal and the second signal intensity of the second audio signal, and determining the feedback suppression configuration parameters according to the signal source position includes but is not limited to the following steps:

[0077] Step S310, when the first signal intensity is less than the second signal intensity, and the difference between the first signal intensity and the second signal intensity is greater than the first intensity threshold, it is determined that the signal source position is the back of the loudspeaker;

[0078] Step S320, when the signal source position is the back of the loudspeaker, it is determined that the suppressor switch in the feedback suppression configuration parameters is closed; or it is determined that the suppressor switch in the feedback suppression configuration parameters is open, and the feedback threshold and the filtering parameters are the acoustic feedback weak degree suppression configuration.

[0079] In this embodiment, if the wireless microphone is located as Figure 3At the L1 position shown, since the first receiving antenna and the receiving antenna are directional antennas, and the first receiving antenna at the front points forward while the second receiving antenna at the back points backward, at this time, the first signal strength L1 of the first audio signal collected by the first receiving antenna is less than the second signal strength L2 of the second audio signal collected by the second receiving antenna, and the difference between the second signal strength L2 and the first signal strength L1 is greater than the preset first intensity threshold L'. Therefore, if the signal source position analysis module determines that the condition "L1 < L2 and (L2 - L1) > L'" holds, it can be determined that the signal source is at the back of the loudspeaker. In this case, generally no啸叫 (howling) will occur or the probability is very low, and the feedback suppression configuration parameters of weak sound feedback suppression or the feedback suppression configuration parameters of sound feedback suppression turned off can be adopted. Further, the sound feedback suppression module can receive the signal source position through a communication line such as a UART serial port, obtain the feedback suppression configuration parameters of weak sound feedback suppression or the feedback suppression configuration parameters of sound feedback suppression turned off from the storage module according to the signal source position, control the suppression circuit to conduct or disconnect according to the suppressor switch in the feedback suppression configuration parameters, detect the howling frequency points according to the feedback threshold in the feedback suppression configuration parameters, and set the notch filter parameters according to the filtering parameters to filter the howling frequency points.

[0080] According to some embodiments of the present invention, in step S120, the step of determining the signal source position according to the first signal strength of the first audio signal and the second signal strength of the second audio signal and determining the feedback suppression configuration parameters according to the signal source position further includes but is not limited to the following steps:

[0081] Step S410, when the second signal strength is less than the first signal strength, and the difference between the second signal strength and the first signal strength is greater than the first intensity threshold, and the first signal strength is less than the second intensity threshold, it is determined that the signal source position is within the feedback action range in front of the loudspeaker;

[0082] Step S420, when the signal source position is within the feedback action range in front of the loudspeaker, it is determined that the suppressor switch in the feedback suppression configuration parameters is turned on, and the feedback threshold and the filtering parameters are the sound feedback strong degree suppression configuration.

[0083] In this embodiment, if the wireless microphone is located as Figure 3 It should be noted that the term "啸叫" in the original text is not a common English word in this context. I've translated it as "howling" for the purpose of maintaining the meaning as accurately as possible, but it might need to be adjusted according to the specific technical meaning in the relevant field.At position L2, since the first receiving antenna and the receiving antenna are directional antennas, and the first receiving antenna at the front points forward and the second receiving antenna at the back points backward, the first signal strength L1 of the first audio signal collected by the first receiving antenna is greater than the second signal strength L2 of the second audio signal collected by the second receiving antenna, and the difference between the first signal strength L1 and the second signal strength L2 is greater than the preset first strength threshold L'. Therefore, if the signal source location analysis module determines that the condition "L1>L2, and (L2-L1)>L'" is true, it can be determined that the signal source is in front of the loudspeaker. Furthermore, if it further determines that the condition "L1>L" (the second intensity threshold) is true, it can be determined that the signal source is within the feedback range in front of the loudspeaker. In this case, the probability of howling is high, and feedback suppression configuration parameters for suppressing acoustic feedback intensity can be used. Further, the acoustic feedback suppression module can receive the signal source location via a communication line such as a UART serial port, retrieve the feedback suppression configuration parameters for suppressing acoustic feedback intensity from the storage module based on the signal source location, control the suppression circuit to conduct according to the suppressor switch in the feedback suppression configuration parameters, detect howling frequency points according to the feedback threshold in the feedback suppression configuration parameters, and set the notch filter parameters according to the filtering parameters to filter the howling frequency points.

[0084] In another embodiment, if the condition "L1>L2 and (L2-L1)>L'" is met, it can be determined that the signal source is in front of the loudspeaker. Then, the distance of the signal source in front of the loudspeaker is further determined based on the first signal strength. Based on the curve fitting relationship between this distance value and the feedback threshold, notch number, maximum attenuation depth, attenuation depth step, and bandwidth (q value), the corresponding feedback suppression configuration parameters are determined, thereby achieving more refined configuration of various related suppression parameters and improving the output effect of the original sound.

[0085] According to some embodiments of the present invention, in step S120, the step of determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, further includes, but is not limited to, the following steps:

[0086] Step S510: When the difference between the second signal strength and the first signal strength is less than the first strength threshold, the signal source location is determined to be the side of the loudspeaker.

[0087] Step S520: When the signal source is within the feedback range of the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is set to open, and the feedback threshold and filtering parameters are configured for moderate acoustic feedback suppression.

[0088] In this embodiment, if the wireless microphone is located as follows: Figure 3At position L3, the first signal strength L1 of the first audio signal acquired by the first receiving antenna is close to the second signal strength L2 of the second audio signal acquired by the second receiving antenna; that is, the difference between the first signal strength L1 and the second signal strength L2 is less than the preset first strength threshold L'. Therefore, if the signal source location analysis module determines that the condition "|L2-L1|≤L'" is true, it can be determined that the signal source is on the side of the loudspeaker. In this case, the degree of howling is generally moderate, and the feedback suppression configuration parameters for moderate acoustic feedback suppression can be used. Furthermore, the acoustic feedback suppression module can receive the signal source location through communication lines such as UART serial port, obtain the feedback suppression configuration parameters for moderate acoustic feedback suppression from the storage module based on the signal source location, control the suppression circuit to conduct according to the suppressor switch in the feedback suppression configuration parameters, detect the howling frequency point according to the feedback threshold in the feedback suppression configuration parameters, and set the notch filter parameters according to the filtering parameters to filter the howling frequency point.

[0089] Furthermore, if the condition "|L2-L1|≤L'" is met, it can be further determined whether the conditions "L1>L"' (third intensity threshold) or "L2>L"'" are met. If they are met, it can be determined that the signal source is at a relatively far distance from the microphone. In this case, the feedback suppression configuration parameter with acoustic feedback suppression turned off can be used. Otherwise, the feedback suppression configuration parameter with moderate acoustic feedback suppression can be used.

[0090] According to some embodiments of the present invention, step S130, performing acoustic feedback suppression control on the first audio signal or the second audio signal according to the feedback suppression configuration parameters, includes the following steps:

[0091] Step S610: Control the suppression circuit to be turned on or off according to the suppressor switch in the feedback suppression configuration parameters. When the suppression circuit is off, the first audio signal or the second audio signal is directly output. When the suppression circuit is on, control the suppression circuit according to the feedback threshold and filtering parameters in the feedback suppression configuration parameters to perform feedback suppression on the first audio signal or the second audio signal.

[0092] In this embodiment, refer to Figure 4 The control processing unit in the acoustic feedback suppression module can control the suppression circuit to be turned on or off according to the suppressor switch in the feedback suppression configuration parameters. For example, if the suppressor switch in the feedback suppression configuration parameters is on, the suppression circuit is turned on, and the input signal is processed by the suppression circuit and output from the output terminal. If the suppressor switch in the feedback suppression configuration parameters is off, the suppression circuit is turned off, and the input signal is directly transmitted to the output terminal for output.

[0093] It is understood that the input signal of the acoustic feedback suppression module can be a first audio signal from the first receiving antenna or a second audio signal from the second receiving antenna. In another example, the audio signal with lower noise value between the first and second audio signals can also be selected as the input signal.

[0094] According to some embodiments of the present invention, step S610, which controls the suppression circuit according to the feedback threshold and filtering parameters in the feedback suppression configuration parameters to perform feedback suppression on the first audio signal or the second audio signal, includes the following steps:

[0095] Step S710: Perform a Fourier transform on the first audio signal or the second audio signal after analog-to-digital conversion to obtain amplitude information at each frequency point;

[0096] Step S720: Compare the frequency point amplitude information with the feedback threshold, filter out the frequency points whose frequency point amplitude information is greater than the feedback threshold, and perform a second filtering on the filtered frequency points according to the number of notch filters in the feedback suppression configuration parameters.

[0097] Step S730: Set the notch filter according to the filtering parameters, and filter the frequency points of the first audio signal or the second audio signal after secondary screening according to the notch filter.

[0098] In this embodiment, when the suppression circuit is turned on, firstly, the suppression circuit performs a Fourier transform on the time-domain audio signal (first audio signal or second audio signal) after analog-to-digital conversion to obtain the amplitude information of each frequency point of the audio signal; further, in order to prevent abrupt changes in frequency points, the audio signal after Fourier transform can be subjected to RC filtering. The time constant of the RC filter can be determined by the sensitivity (FSensi), where sensitivity characterizes the degree of sensitivity of the notch filter algorithm to the input signal. It can be set to 0-10 levels, with 10 being the most sensitive. Sensitivity can be used as one of the parameters for feedback suppression configuration to adaptively configure the sensitivity in actual process.

[0099] Secondly, the feedback howling frequency detection unit extracts the howling frequency based on the characteristics of the feedback howling point (no harmonics and continuous characteristics), and compares the amplitude information of each frequency point obtained above with the feedback threshold parameter in the feedback suppression configuration parameters. For frequency points with amplitudes greater than the feedback threshold, filtering is required. Furthermore, since the hardware (such as DSP chip) of the notch filter unit has limited working capabilities, the number of frequency points with amplitudes greater than the feedback threshold can be counted, and the number of frequency points actually entering the notch filter unit for processing can be limited by the notch number parameter in the feedback suppression configuration parameters.

[0100] Then, the notch filter unit performs notch filtering on the howling frequency points selected based on the feedback threshold and the number of notches. The filtering characteristics of the notch filter unit are determined by the maximum attenuation depth, attenuation depth step, and bandwidth (q value) in the feedback suppression configuration parameters. If the obtained frequency point amplitude difference is within the "maximum attenuation depth" range, it is attenuated according to the actual amplitude; otherwise, it is attenuated according to the maximum attenuation depth.

[0101] This invention also provides a loudspeaker feedback adaptive adjustment system, comprising:

[0102] The first module is used to acquire a first audio signal through a first receiving antenna and acquire a second audio signal through a second receiving antenna. The first receiving antenna is disposed on one side of the loudspeaker and the enhancement direction of the first receiving antenna is the same as the radiation direction of the loudspeaker. The second receiving antenna is disposed opposite to the first receiving antenna and the enhancement direction of the second receiving antenna is opposite to the enhancement direction of the first receiving antenna.

[0103] The second module is used to determine the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and to determine the feedback suppression configuration parameters based on the signal source location. The feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters.

[0104] The third module is used to control the acoustic feedback suppression of the first audio signal or the second audio signal according to the feedback suppression configuration parameters.

[0105] It is understood that the content of the above-mentioned loudspeaker howling adaptive adjustment method embodiment is applicable to this system embodiment. The specific functions implemented by this system embodiment are the same as those of the above-mentioned loudspeaker howling adaptive adjustment method embodiment, and the beneficial effects achieved are also the same as those achieved by the above-mentioned loudspeaker howling adaptive adjustment method embodiment.

[0106] Reference Figure 6 , Figure 6 This is a schematic diagram of a loudspeaker feedback adaptive adjustment device according to an embodiment of the present invention. The loudspeaker feedback adaptive adjustment device of this embodiment includes one or more control processors and a memory. Figure 6 The example consists of a control processor and a memory.

[0107] The control processor and memory can be connected via a bus or other means. Figure 6 Taking the example of a connection between China and Israel via a bus.

[0108] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the control processor, and these remote memories can be connected to the loudspeaker feedback adaptive adjustment device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0109] Those skilled in the art will understand that Figure 6 The device structure shown does not constitute a limitation on the loudspeaker feedback adaptive adjustment device, which may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0110] The non-transient software program and instructions required to implement the loudspeaker howling adaptive adjustment method applied to the loudspeaker howling adaptive adjustment device in the above embodiments are stored in the memory. When executed by the controlled processor, the loudspeaker howling adaptive adjustment method applied to the loudspeaker howling adaptive adjustment device in the above embodiments is executed.

[0111] Furthermore, one embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions that are executed by one or more control processors, causing the one or more control processors to perform the loudspeaker howling adaptive adjustment method in the above method embodiment.

[0112] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0113] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for adaptive adjustment of loudspeaker howling, characterized in that, Includes the following steps: A first audio signal is acquired through a first receiving antenna, and a second audio signal is acquired through a second receiving antenna. The first receiving antenna is disposed on one side of the loudspeaker and its enhancement direction is the same as the radiation direction of the loudspeaker. The second receiving antenna is disposed opposite to the first receiving antenna and its enhancement direction is opposite to that of the first receiving antenna. The signal source location is determined based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and feedback suppression configuration parameters are determined based on the signal source location, wherein the feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters; The first audio signal or the second audio signal is subjected to acoustic feedback suppression control according to the feedback suppression configuration parameters; Before the step of determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, the loudspeaker feedback adaptive adjustment method further includes the following steps: The first multipath interference value of the first audio signal and the second multipath interference value of the second audio signal are compared with the multipath interference threshold respectively. If the first multipath interference value or the second multipath interference value is greater than the multipath interference threshold, the signal source position is not updated. The first noise value of the first audio signal and the second noise value of the second audio signal are compared with a noise threshold. If the first noise value or the second noise value is greater than the noise threshold, the signal source position is not updated.

2. The loudspeaker howling adaptive adjustment method according to claim 1, characterized in that, The step of determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, includes the following steps: When the first signal strength is less than the second signal strength, and the difference between the second signal strength and the first signal strength is greater than the first strength threshold, the signal source location is determined to be the back of the loudspeaker. When the signal source is located behind the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is determined to be off; or the suppressor switch in the feedback suppression configuration parameters is determined to be on, and the feedback threshold and filtering parameters are configured to suppress the degree of acoustic feedback weakness.

3. The loudspeaker feedback adaptive adjustment method according to claim 2, characterized in that, The step of determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, includes the following steps: When the second signal strength is less than the first signal strength, and the difference between the first signal strength and the second signal strength is greater than the first strength threshold, and the first signal strength is less than the second strength threshold, then the signal source location is determined to be within the feedback range in front of the loudspeaker. When the signal source is located within the feedback range in front of the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is set to "on", and the feedback threshold and filtering parameters are configured to suppress the intensity of acoustic feedback.

4. The loudspeaker howling adaptive adjustment method according to claim 3, characterized in that, The step of determining the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and determining the feedback suppression configuration parameters based on the signal source location, includes the following steps: When the difference between the second signal strength and the first signal strength is less than the first strength threshold, the signal source location is determined to be the side of the loudspeaker; When the signal source is located within the feedback range of the loudspeaker, the suppressor switch in the feedback suppression configuration parameters is set to "on", and the feedback threshold and filtering parameters are configured for moderate acoustic feedback suppression.

5. The loudspeaker howling adaptive adjustment method according to claim 1, characterized in that, The step of controlling the acoustic feedback suppression of the first audio signal or the second audio signal according to the feedback suppression configuration parameters includes the following steps: The suppression circuit is controlled to be turned on or off according to the suppressor switch in the feedback suppression configuration parameters. When the suppression circuit is off, the first audio signal or the second audio signal is directly output. When the suppression circuit is on, the suppression circuit is controlled according to the feedback threshold and filtering parameters in the feedback suppression configuration parameters to suppress the first audio signal or the second audio signal.

6. The loudspeaker howling adaptive adjustment method according to claim 5, characterized in that, The step of controlling the suppression circuit according to the feedback threshold and filtering parameters in the feedback suppression configuration parameters to perform feedback suppression on the first audio signal or the second audio signal includes the following steps: Perform a Fourier transform on the first audio signal or the second audio signal after analog-to-digital conversion to obtain the amplitude information of each frequency point; The frequency point amplitude information is compared with the feedback threshold, and frequency points with frequency point amplitude information greater than the feedback threshold are selected. The selected frequency points are then further filtered according to the number of notch filters in the feedback suppression configuration parameters. The notch filter is set according to the filtering parameters, and the frequency points of the first audio signal or the second audio signal after secondary screening are filtered according to the notch filter.

7. A loudspeaker feedback adaptive adjustment system, characterized in that, include: The first module is used to acquire a first audio signal through a first receiving antenna and acquire a second audio signal through a second receiving antenna. The first receiving antenna is disposed on one side of the loudspeaker and the enhancement direction of the first receiving antenna is the same as the radiation direction of the loudspeaker. The second receiving antenna is disposed opposite to the first receiving antenna and the enhancement direction of the second receiving antenna is opposite to the enhancement direction of the first receiving antenna. The second module is used to determine the signal source location based on the first signal strength of the first audio signal and the second signal strength of the second audio signal, and to determine feedback suppression configuration parameters based on the signal source location, wherein the feedback suppression configuration parameters include a suppressor switch, a feedback threshold, and filtering parameters; The third module is used to perform acoustic feedback suppression control on the first audio signal or the second audio signal according to the feedback suppression configuration parameters. Prior to the second module, the loudspeaker howling adaptive adjustment system is also used to perform the following steps: The first multipath interference value of the first audio signal and the second multipath interference value of the second audio signal are compared with the multipath interference threshold respectively. If the first multipath interference value or the second multipath interference value is greater than the multipath interference threshold, the signal source position is not updated. The first noise value of the first audio signal and the second noise value of the second audio signal are compared with a noise threshold. If the first noise value or the second noise value is greater than the noise threshold, the signal source position is not updated.

8. A loudspeaker feedback adaptive adjustment device, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the loudspeaker howling adaptive adjustment method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a processor-executable program, characterized in that, When the processor executes the program, it is used to implement the loudspeaker howling adaptive adjustment method as described in any one of claims 1 to 6.

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