Hearing aid system implementing feedback suppression function and method, device, processor and computer readable storage medium thereof

Abstract

The application relates to a hearing aid system for realizing a feedback suppression function, comprising a vent, a first microphone, a second microphone and a signal processing unit, the vent penetrates through the hearing aid and is used for connecting the space inside and outside the ear canal, the first microphone is arranged on the side of the hearing aid far from the ear canal and is used for picking up a first sound signal, the second microphone is arranged on the side of the hearing aid close to the ear canal and is located in the acoustic path range of the vent, and the signal processing unit is connected with the first microphone and the second microphone; the signal processing unit applies frequency-dependent delay and amplitude adjustment to the second sound signal to generate a compensation signal. The hearing aid system for realizing the feedback suppression function, the method, the device, the processor and the computer readable storage medium thereof have high compatibility and easy realization, a resistance is additionally arranged in the periphery, a complicated customized algorithm does not need to be developed, high-performance feedback suppression can be realized, and the development threshold and period are greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of hearing aids, and more particularly to the field of microphone layout and signal processing, specifically to a hearing aid system, method, device, processor, and computer-readable storage medium that implements feedback suppression function. Background Technology

[0002] During the use of a hearing aid, the amplified sound emitted by the receiver can leak back to the microphone through various paths within the ear canal. When the leaked sound is amplified again to a critical point, it creates a piercing acoustic feedback whistling sound. This is the main factor limiting the maximum stable gain of a hearing aid.

[0003] Acoustic feedback is a major concern among hearing aid users. According to international statistics, approximately 24% of hearing aid users complain about acoustic feedback. Earlier data from the MarketTrak VI survey (2000) showed that "acoustic feedback / whistling / noise" ranked 11th among the 32 main reasons users stopped using hearing aids. A market survey in the same year revealed that as many as 75% of hearing aid users experienced acoustic feedback daily, indicating that this problem was widespread and urgently needed to be addressed at the time. In the 21st century, despite significant advancements in feedback suppression technology, users' increasing demands for wearing comfort, especially regarding vents, mean that acoustic feedback remains a challenge requiring continuous optimization.

[0004] Vents balance the air pressure inside and outside the ear canal, alleviating the occlusion effect and making users feel that their "ear canal is open," thus improving naturalness. User complaints about their own voice, such as a hollow sound or sounding like "speaking in a barrel," are precisely due to the occlusion effect caused by a closed ear canal. Survey data from 2000 showed that "unbearable sound quality of one's own voice" ranked 8th among reasons for not using hearing aids. However, vents are precisely the primary leakage path for acoustic feedback. Research shows that opening the ear canal to reduce the occlusion effect significantly increases sound leakage, making hearing aids more prone to acoustic feedback. Traditionally, opening vents means sacrificing some gain, especially low-frequency gain, resulting in some hearing-impaired users not receiving sufficient compensation. For example, for users with hearing loss greater than 80dB, clinical recommendations suggest avoiding vents larger than 2.0mm to prevent feedback. How to effectively suppress acoustic feedback while maintaining the comfort provided by large vents (≥2mm) has long been a pain point that the industry has failed to perfectly resolve.

[0005] Currently, most mainstream hearing aid chips support directional microphone processing. The basic principle is to use two or more omnidirectional microphones, through delay subtraction or adaptive beamforming algorithms, to create null points in a specific direction, thereby attenuating noise and improving the forward signal-to-noise ratio. This technology is primarily used for environmental noise suppression, rather than specifically for acoustic feedback suppression. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a hearing aid system, method, device, processor and computer-readable storage medium that achieves feedback suppression function with low power consumption, high compatibility and easy implementation.

[0007] To achieve the above objectives, the hearing aid system, method, apparatus, processor, and computer-readable storage medium of the present invention that implement feedback suppression function are as follows: The hearing aid system that implements feedback suppression is characterized by comprising a vent, a first microphone, a second microphone, and a signal processing unit. The vent penetrates the hearing aid and connects the inner and outer spaces of the ear canal. The first microphone is located on the side of the hearing aid away from the ear canal and is used to pick up a first acoustic signal. The second microphone is located on the side of the hearing aid closer to the ear canal and within the acoustic path of the vent and is used to pick up a second acoustic signal. The signal processing unit is connected to the first and second microphones. The signal processing unit applies frequency-dependent delay and amplitude adjustment to the second acoustic signal to generate a compensation signal and combines the first acoustic signal with the compensation signal to form an acoustic null point pointing towards the inside of the ear canal within a predetermined feedback frequency band.

[0008] Preferably, the signal processing unit includes a first-order RC low-pass filter and a gain adjustment module. The first-order RC low-pass filter is connected to the output of the second microphone and is used to introduce the frequency-dependent delay. The gain adjustment module is used to amplify the first acoustic signal with a first gain and amplify the second acoustic signal processed by the RC low-pass filter with a second gain. The signal processing unit combines the first acoustic signal with the compensation signal, specifically by subtracting the amplified first acoustic signal from the amplified second acoustic signal. The signal processing unit further includes a digital delay module, which applies an additional fixed delay to the first or second acoustic signal. The frequency-dependent delay is achieved by the digital delay module and the first-order RC low-pass filter together.

[0009] Preferably, if the time constant of the first-order RC low-pass filter is less than 50 μs, the digital delay module provides an additional delay of 10 μs to 30 μs to maintain a feedback attenuation of at least 10 dB in the 2 kHz to 5 kHz frequency band.

[0010] Preferably, the time constant of the first-order RC low-pass filter is 50μs to 80μs, the ratio of the second gain to the first gain is 1.6 to 1.9, the diameter of the vent is 2.0mm to 3.0mm, and the acoustic center distance between the first microphone and the second microphone is 10mm to 20mm. The signal processing unit combines the first and second acoustic signals to make the response attenuation of sound from the inside of the ear canal relative to sound from the outside of the ear canal greater than or equal to 10dB in the frequency range of 2kHz to 5kHz.

[0011] The hearing aid method for implementing feedback suppression using the above system is characterized by the following steps: (1) The first sound signal outside the ear canal is picked up by the first microphone, and the second sound signal inside the ear canal is picked up by the second microphone, wherein the second microphone is located within the acoustic path range of the vent hole through the hearing aid; (2) Apply frequency-dependent delay and amplitude adjustment to the second acoustic signal to generate a compensation signal; (3) The first acoustic signal and the compensation signal are combined to form an acoustic zero point pointing towards the inside of the ear canal within a predetermined feedback frequency band, thereby attenuating and suppressing the acoustic feedback signal inside the ear canal. In step (2), applying a frequency-dependent delay to the second acoustic signal is specifically achieved through a first-order RC low-pass filter. Adjusting the amplitude of the acoustic signal is specifically achieved by applying a first gain to the first acoustic signal and a second gain to the second acoustic signal after processing by the first-order RC low-pass filter through a gain adjustment module. In step (3), combining the first acoustic signal with the compensation signal is specifically achieved by subtracting the amplified first acoustic signal from the amplified second acoustic signal.

[0012] Preferably, the time constant of the first-order RC low-pass filter is 50μs to 80μs, the ratio of the second gain to the first gain is 1.6 to 1.9, and the diameter of the vent hole is 2.0mm to 3.0mm.

[0013] Preferably, the method further includes the following steps: An additional fixed delay is applied to the first or second acoustic signal by a digital delay module, which together with the first-order RC low-pass filter provides the frequency-dependent delay. When the time constant of the first-order RC low-pass filter is less than 50 μs, an additional delay of 10 μs to 30 μs is provided by the digital delay module, maintaining a feedback attenuation of at least 10 dB in the frequency band of 2 kHz to 5 kHz.

[0014] The main feature of this device for implementing feedback suppression is that the device comprises: A processor is configured to execute computer-executable instructions; The memory stores one or more computer-executable instructions, which, when executed by the processor, implement the steps of the method for implementing the feedback suppression function described above.

[0015] The processor that implements the feedback suppression function is characterized in that the processor is configured to execute computer-executable instructions, and when the computer-executable instructions are executed by the processor, the various steps of the above-described method for implementing the feedback suppression function are implemented.

[0016] The main feature of this computer-readable storage medium is that it stores a computer program thereon, which can be executed by a processor to implement the various steps of the method for implementing the feedback suppression function described above.

[0017] The hearing aid system, method, device, processor, and computer-readable storage medium of this invention, which implements feedback suppression, achieves extremely low power consumption. Core processing is completed in the analog domain (RC filtering, fixed gain), and the back-end DSP only needs to perform simple time-domain mixing and subtraction. This is of great significance for hearing aids that rely on button batteries for power and are extremely sensitive to power consumption. This invention has high compatibility and ease of implementation. Currently, mainstream hearing aid chips support dual-microphone directional configurations and allow independent preamplification settings for each input channel. This solution can directly utilize these existing functions by adding an external resistor, achieving high-performance feedback suppression without developing complex custom algorithms, greatly reducing the R&D threshold and cycle time. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the hearing aid system that implements the feedback suppression function of the present invention.

[0019] Figure label: 1. Vent 2 First microphone 3 Second microphone 4 Signal Processing Unit 5 loudspeakers 6. First-order RC low-pass filter 7. Gain Adjustment Module 8 Digital Delay Modules 9. Signal Mixer Detailed Implementation

[0020] To more clearly describe the technical content of the present invention, the following description is provided in conjunction with specific embodiments.

[0021] The hearing aid system of the present invention, which implements feedback suppression function, includes a vent, a first microphone, a second microphone, and a signal processing unit. The vent penetrates the hearing aid and connects the inner and outer spaces of the ear canal. The first microphone is disposed on the side of the hearing aid away from the ear canal and is used to pick up a first sound signal. The second microphone is disposed on the side of the hearing aid closer to the ear canal and within the acoustic path range of the vent and is used to pick up a second sound signal. The signal processing unit is connected to the first and second microphones. The signal processing unit applies frequency-dependent delay and amplitude adjustment to the second sound signal to generate a compensation signal, and combines the first sound signal with the compensation signal to form an acoustic null point pointing inwards into the ear canal within a predetermined feedback frequency band.

[0022] In a preferred embodiment of the present invention, the signal processing unit includes a first-order RC low-pass filter and a gain adjustment module. The first-order RC low-pass filter is connected to the output of the second microphone and is used to introduce the frequency-dependent delay. The gain adjustment module is used to amplify the first sound signal with a first gain and amplify the second sound signal processed by the RC low-pass filter with a second gain. The signal processing unit combines the first sound signal and the compensation signal, specifically by subtracting the amplified first sound signal from the amplified second sound signal. The digital delay module applies an additional fixed delay to the first or second acoustic signal, and the frequency-dependent delay is achieved by the digital delay module and the first-order RC low-pass filter together.

[0023] In a preferred embodiment of the present invention, if the time constant of the first-order RC low-pass filter is less than 50μs, the digital delay module provides an additional delay of 10μs to 30μs to maintain a feedback attenuation of at least 10dB in the 2kHz to 5kHz frequency band.

[0024] In a preferred embodiment of the present invention, the time constant of the first-order RC low-pass filter is 50μs to 80μs, the ratio of the second gain to the first gain is 1.6 to 1.9, the diameter of the vent is 2.0mm to 3.0mm, and the acoustic center distance between the first microphone and the second microphone is 10mm to 20mm; the signal processing unit combines the first sound signal and the second sound signal to make the response attenuation of sound from the inside of the ear canal relative to sound from the outside of the ear canal greater than or equal to 10dB in the frequency range of 2kHz to 5kHz.

[0025] The hearing aid method of the present invention, which utilizes the above-described system to achieve feedback suppression function, includes the following steps: (1) The first sound signal outside the ear canal is picked up by the first microphone, and the second sound signal inside the ear canal is picked up by the second microphone, wherein the second microphone is located within the acoustic path range of the vent hole through the hearing aid; (2) Apply frequency-dependent delay and amplitude adjustment to the second acoustic signal to generate a compensation signal; (3) The first acoustic signal and the compensation signal are combined to form an acoustic zero point pointing towards the inside of the ear canal within a predetermined feedback frequency band, thereby attenuating and suppressing the acoustic feedback signal inside the ear canal. In step (2), applying a frequency-dependent delay to the second acoustic signal is specifically achieved through a first-order RC low-pass filter. Adjusting the amplitude of the acoustic signal is specifically achieved by applying a first gain to the first acoustic signal and a second gain to the second acoustic signal after processing by the first-order RC low-pass filter through a gain adjustment module. In step (3), combining the first acoustic signal with the compensation signal is specifically achieved by subtracting the amplified first acoustic signal from the amplified second acoustic signal.

[0026] In a preferred embodiment of the present invention, the time constant of the first-order RC low-pass filter is 50μs to 80μs, the ratio of the second gain to the first gain is 1.6 to 1.9, and the diameter of the vent hole is 2.0mm to 3.0mm.

[0027] In a preferred embodiment of the present invention, the method further includes the following steps: An additional fixed delay is applied to the first or second acoustic signal by a digital delay module, which together with the first-order RC low-pass filter provides the frequency-dependent delay. When the time constant of the first-order RC low-pass filter is less than 50 μs, an additional delay of 10 μs to 30 μs is provided by the digital delay module, maintaining a feedback attenuation of at least 10 dB in the frequency band of 2 kHz to 5 kHz.

[0028] The device for implementing feedback suppression function of the present invention, wherein the device includes: A processor is configured to execute computer-executable instructions; The memory stores one or more computer-executable instructions, which, when executed by the processor, implement the steps of the method for implementing the feedback suppression function described above.

[0029] The processor of the present invention implements the feedback suppression function, wherein the processor is configured to execute computer-executable instructions, and when the computer-executable instructions are executed by the processor, the various steps of the method for implementing the feedback suppression function described above are implemented.

[0030] The computer-readable storage medium of the present invention stores a computer program thereon, which can be executed by a processor to implement the various steps of the method for implementing the feedback suppression function described above.

[0031] This invention proposes an innovative microphone layout and signal processing strategy that reverses the directionality of technology and is specifically designed for acoustic feedback suppression.

[0032] The specific structure is as follows: The first microphone (external ear canal microphone): located on the outside of the hearing aid body, near the ear canal opening, mainly picks up pure ambient sound from the outside world.

[0033] The second microphone (in-ear microphone): is located in the part of the hearing aid that goes deep into the ear canal, close to the receiver.

[0034] Vent: It runs through the hearing aid, connects the inside and outside of the ear canal, and is coupled to the acoustic paths of the two microphones.

[0035] This scheme treats the microphone inside the ear canal as the "rear microphone" of a directional array, and the microphone outside the ear canal as the "front microphone." Through signal processing, a beam with a directional null point aligned with the inside of the ear canal (i.e., the direction of the acoustic feedback source) is constructed. In this way, the system can effectively attenuate leakage sound (feedback) from inside the ear canal while maintaining high sensitivity to ambient sound outside the ear canal.

[0036] In traditional directional technologies, the microphone spacing determines the effective operating frequency band. A spacing of 15–20 mm results in limited directivity in the 2–5 kHz feedback band. To achieve deep feedback attenuation with small spacing, this invention proposes an "analog-digital hybrid delay and amplitude compensation" mechanism: Frequency-dependent delay: Add an RC filter to the microphone path inside the ear canal (using the DC blocking capacitor in the existing microphone bias circuit, which can be achieved by adding only one resistor) to form a frequency-dependent group delay, simulating the phase difference at a larger spacing.

[0037] Amplitude compensation: By configuring different preamplifier gains for the two microphones, a specific gain ratio is formed, so that the two signals can achieve the best conditions for amplitude cancellation.

[0038] Using the above method, a microphone array with a physical spacing of 15-20mm can produce an acoustic cancellation effect in the 2-5kHz key frequency band that is equivalent to a spacing of more than 40mm.

[0039] The present invention provides a hearing aid with feedback suppression function, comprising: A vent, extending through the hearing aid, serves to connect the inner and outer spaces of the ear canal; The first microphone is located on the side of the hearing aid away from the ear canal and is used to pick up the first sound signal; The second microphone is located on the side of the hearing aid closer to the ear canal and within the acoustic path of the vent, and is used to pick up the second sound signal. A signal processing unit, connected to the first microphone and the second microphone, is configured to: A frequency-dependent delay and amplitude adjustment are applied to the second acoustic signal to generate a compensation signal; The first acoustic signal is combined with the compensation signal to form an acoustic zero point pointing towards the inside of the ear canal within a predetermined feedback frequency band.

[0040] The signal processing unit includes: A first-order RC low-pass filter, connected to the output of the second microphone, is used to introduce the frequency-dependent delay; and A gain adjustment module is used to amplify the first acoustic signal with a first gain and amplify the second acoustic signal processed by the RC low-pass filter with a second gain. The combination involves subtracting the amplified first sound signal from the amplified second sound signal.

[0041] The time constant of the RC low-pass filter is 50μs to 80μs, and the ratio of the second gain to the first gain (G2 / G1) is 1.6 to 1.9.

[0042] The diameter of the vent is in the range of 2.0 mm to 3.0 mm, so that the acoustic transmission characteristics of the vent in the frequency band of 2 kHz to 5 kHz are matched with the time constant of the RC low-pass filter, so as to achieve the acoustic zero point together.

[0043] The signal processing unit further includes a digital delay module for applying an additional fixed delay to the first acoustic signal or the second acoustic signal; and the frequency-dependent delay is provided by the digital delay module and an analog RC filter.

[0044] When the time constant of the RC filter is less than 50μs, the digital delay module provides an additional delay of 10μs to 30μs to maintain a feedback attenuation of at least 10dB in the 2kHz to 5kHz frequency band.

[0045] The acoustic center distance between the first microphone and the second microphone is 10mm to 20mm.

[0046] The signal processing unit, in the frequency range of 2kHz to 5kHz, makes the response attenuation of sound from the inside of the ear canal relative to sound from the outside of the ear canal greater than or equal to 10dB for the combination of the first and second acoustic signals.

[0047] In specific embodiments of the present invention, the following examples are adopted: Example 1: Pure Analog RC Delay Scheme This example uses a pure analog method to implement frequency-dependent delay, which is suitable for application scenarios with extremely stringent power consumption requirements and fixed parameters.

[0048] Hardware configuration: The acoustic center-to-center distance between the first microphone (outside the ear canal) and the second microphone (inside the ear canal) is 15mm.

[0049] Vent hole diameter: 2.5mm.

[0050] An RC low-pass filter is connected in series between the output of the second microphone and the input of the signal processing unit.

[0051] Capacitor value: A DC blocking capacitor commonly used in hearing aid circuits is adopted, with C = 10nF.

[0052] Resistance value: The calculated value is R = 6.5kΩ (corresponding to a time constant of 65μs), and a standard precision resistor of 6.49kΩ is selected.

[0053] Gain configuration: Configure the first microphone preamplifier gain G1 = 1 (reference gain), and the second microphone path (including the RC filter) preamplifier gain G2 = 1.74.

[0054] Signal processing: The DSP module only performs simple subtraction operations: (After RC filtering)

[0055] No complex adaptive algorithms or delay lines are required.

[0056] Performance metrics: Theoretical calculations and simulations have verified that, under these parameter configurations, the system achieves an attenuation of 11.3 dB to 22.7 dB for acoustic feedback signals originating from inside the ear canal within the 2 kHz to 5 kHz frequency band, fully meeting the requirements for suppressing howling.

[0057] Example 2: Simulated RC+DSP Hybrid Delay Scheme This example introduces DSP digital delay, which allows for the use of a smaller RC time constant, thereby enabling the use of smaller resistance values ​​(for easier integration) or flexible adaptation to microphones with different pitches.

[0058] Hardware configuration: The microphone spacing, vent diameter, and capacitance value are the same as in Example 1.

[0059] Reduce the RC time constant: Take R = 3.0kΩ (less than in Example 1) and C = 10nF, then the RC time constant τ_rc = 30μs.

[0060] Signal processing: Analog domain: The second microphone signal first passes through the aforementioned 30μs RC filter, resulting in partial delay and amplitude attenuation.

[0061] Digital Domain: In the DSP, an additional fixed digital delay τ_dsp = 17.2 μs is applied to the second microphone path. This delay can be achieved using a fractional delay filter, or approximated as one sample point (20.8 μs) at a 48 kHz sampling rate with fine-tuning of the coefficients.

[0062] Gain configuration: Recalculate and configure the gain ratio G2 / G1 = 1.198.

[0063] Finally, perform the subtraction: (Signal_Mic2 (after RC filtering), τ_dsp).

[0064] Technical effects: This hybrid scheme also achieves perfect phase matching at 3.5kHz, with a theoretical zero depth exceeding 30dB. At 2kHz and 5kHz, the feedback attenuation reaches -19.3dB and -21.7dB respectively, far exceeding the design target of 10dB.

[0065] Advantages: The resistance value is reduced from 6.5kΩ to 3kΩ, making it easier to integrate in the analog front end; at the same time, it increases the flexibility of the design, allowing for adaptation to different microphone pitch tolerances by adjusting the digital delay.

[0066] For the specific implementation scheme of this embodiment, please refer to the relevant descriptions in the above embodiments, which will not be repeated here.

[0067] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0068] It should be noted that in the description of this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means at least two.

[0069] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

[0070] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution device. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0071] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The corresponding program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0072] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0073] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.

[0074] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0075] The hearing aid system, method, device, processor, and computer-readable storage medium of this invention, which implements feedback suppression, achieves extremely low power consumption. Core processing is completed in the analog domain (RC filtering, fixed gain), and the back-end DSP only needs to perform simple time-domain mixing and subtraction. This is of great significance for hearing aids that rely on button batteries for power and are extremely sensitive to power consumption. This invention has high compatibility and ease of implementation. Currently, mainstream hearing aid chips support dual-microphone directional configurations and allow independent preamplification settings for each input channel. This solution can directly utilize these existing functions by adding an external resistor, achieving high-performance feedback suppression without developing complex custom algorithms, greatly reducing the R&D threshold and cycle time.

[0076] In this specification, the invention has been described with reference to specific embodiments thereof. However, it will be apparent that various modifications and variations can be made without departing from the spirit and scope of the invention. Therefore, the specification and drawings should be considered illustrative rather than restrictive.

Claims

1. A hearing aid system that implements feedback suppression function, characterized in that, The system includes a vent, a first microphone, a second microphone, and a signal processing unit. The vent penetrates the hearing aid and connects the inner and outer spaces of the ear canal. The first microphone is located on the side of the hearing aid away from the ear canal and is used to pick up a first acoustic signal. The second microphone is located on the side of the hearing aid closer to the ear canal and within the acoustic path of the vent, and is used to pick up a second acoustic signal. The signal processing unit is connected to the first and second microphones. The signal processing unit applies frequency-dependent delay and amplitude adjustment to the second acoustic signal to generate a compensation signal, and combines the first acoustic signal with the compensation signal to form an acoustic null point pointing towards the inside of the ear canal within a predetermined feedback frequency band.

2. The hearing aid system for implementing feedback suppression function according to claim 1, characterized in that, The signal processing unit includes a first-order RC low-pass filter and a gain adjustment module. The first-order RC low-pass filter is connected to the output of the second microphone and is used to introduce the frequency-dependent delay. The gain adjustment module is used to amplify the first sound signal with a first gain and amplify the second sound signal processed by the RC low-pass filter with a second gain. The signal processing unit combines the first sound signal and the compensation signal, specifically by subtracting the amplified first sound signal from the amplified second sound signal. The signal processing unit further includes a digital delay module, which applies an additional fixed delay to the first or second acoustic signal. The frequency-dependent delay is achieved by the digital delay module and the first-order RC low-pass filter together.

3. The hearing aid system for implementing feedback suppression function according to claim 2, characterized in that, If the time constant of the first-order RC low-pass filter is less than 50μs, the digital delay module provides an additional delay of 10μs to 30μs, maintaining a feedback attenuation of at least 10dB in the 2kHz to 5kHz frequency band.

4. The hearing aid system for implementing feedback suppression function according to claim 1, characterized in that, The time constant of the first-order RC low-pass filter is 50μs to 80μs, the ratio of the second gain to the first gain is 1.6 to 1.9, the diameter of the vent is 2.0mm to 3.0mm, and the acoustic center distance between the first microphone and the second microphone is 10mm to 20mm. The signal processing unit combines the first and second acoustic signals to make the response attenuation of sound from the inside of the ear canal relative to sound from the outside of the ear canal greater than or equal to 10dB in the frequency range of 2kHz to 5kHz.

5. A method for implementing feedback suppression function based on the system of claim 1, characterized in that, The method includes the following steps: (1) The first sound signal outside the ear canal is picked up by the first microphone, and the second sound signal inside the ear canal is picked up by the second microphone, wherein the second microphone is located within the acoustic path range of the vent hole through the hearing aid; (2) Apply frequency-dependent delay and amplitude adjustment to the second acoustic signal to generate a compensation signal; (3) The first acoustic signal and the compensation signal are combined to form an acoustic zero point pointing towards the inside of the ear canal within a predetermined feedback frequency band, thereby attenuating and suppressing the acoustic feedback signal inside the ear canal. In step (2), applying a frequency-dependent delay to the second acoustic signal is specifically achieved through a first-order RC low-pass filter. The amplitude adjustment of the acoustic signal is specifically achieved by applying a first gain to the first acoustic signal and a second gain to the second acoustic signal after processing by the first-order RC low-pass filter through a gain adjustment module. In step (3), combining the first acoustic signal with the compensation signal is specifically achieved by subtracting the amplified first acoustic signal from the amplified second acoustic signal.

6. The method for implementing feedback suppression function according to claim 5, characterized in that, The time constant of the first-order RC low-pass filter is 50μs to 80μs, the ratio of the second gain to the first gain is 1.6 to 1.9, and the diameter of the vent hole is 2.0mm to 3.0mm.

7. The method for implementing feedback suppression function according to claim 5, characterized in that, The method further includes the following steps: An additional fixed delay is applied to the first or second acoustic signal by a digital delay module, which together with the first-order RC low-pass filter provides the frequency-dependent delay. When the time constant of the first-order RC low-pass filter is less than 50 μs, an additional delay of 10 μs to 30 μs is provided by the digital delay module, maintaining a feedback attenuation of at least 10 dB in the frequency band of 2 kHz to 5 kHz.

8. A device for implementing feedback suppression function, characterized in that, The device includes: A processor is configured to execute computer-executable instructions; A memory that stores one or more computer-executable instructions, which, when executed by the processor, implement the steps of the method for implementing the feedback suppression function as described in any one of claims 5 to 7.

9. A processor that implements feedback suppression function, characterized in that, The processor is configured to execute computer-executable instructions, which, when executed by the processor, implement the steps of the method for implementing the feedback suppression function as described in any one of claims 5 to 7.

10. A computer-readable storage medium, characterized in that, It stores a computer program that can be executed by a processor to implement the steps of the method for implementing the feedback suppression function as described in any one of claims 5 to 7.

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