An active noise reduction system and its calibration method

Abstract

The present invention relates to an active noise reduction system and a calibration method thereof. The system includes: a sound collection device 2, where the sound collection device 2 includes a first sound collection module 21 disposed outdoors for collecting outdoor ambient noise, and a second sound collection module 22 disposed in contact with the building wall for collecting noise conducted by the building wall; a processing device 1, where the processing device 1 is configured to generate a cancellation sound wave according to the outdoor ambient noise and / or the noise conducted by the building wall, and the cancellation sound wave is used to reduce the influence of the outdoor ambient noise or the noise conducted by the building wall on indoor personnel. By adopting the technical solution of the present invention, not only can the outdoor ambient noise be cancelled, but also the noise transmitted through the building wall can be effectively cancelled, thereby achieving a better active noise reduction effect in the indoor environment and improving the comfort of indoor personnel.

Description

Technical Field

[0001] The present invention relates to the technical field of indoor active noise reduction, and in particular to an active noise reduction system and a calibration method thereof. Background Art

[0002] The noise sources in the indoor environment mainly come through doors and windows. In this regard, people usually use soundproof doors and windows to achieve the effect of indoor sound insulation. At the same time, more people currently live in high-rise buildings, and the designs of many high-rise buildings do not meet the sound insulation requirements of the buildings. The noises made by people living in upper floors, such as the sound of dragging a stool or the sound of something falling to the floor, will be transmitted to the ears of people living in lower floors through the floor slab or the wall. Moreover, since the wall has very little loss when outputting noise, the noise can be transmitted through several floors, that is, users separated by several floors can be affected by it, which affects the harmony between neighbors. And if such noises occur when users are sleeping, they will have a greater impact on people's sleep and mood than the noise entering through doors and windows. Therefore, it is necessary to eliminate the noise effects both indoors and outdoors at the same time. Summary of the Invention

[0003] To solve the above-mentioned problems in the prior art, the present invention provides an active noise reduction system, including:

[0004] A sound collection device 2, where the sound collection device 2 includes a first sound collection module 21 arranged outdoors for collecting outdoor environmental noise, and a second sound collection module 22 arranged in contact with the wall for collecting the noise conducted by the building wall;

[0005] A processing device 1, where the processing device 1 is used to generate a cancellation sound wave according to the outdoor environmental noise and / or the noise conducted by the building wall, and the cancellation sound wave is used to reduce the influence of the outdoor environmental noise or the noise conducted by the building wall on indoor personnel.

[0006] Further, the wall is provided with a receiving cavity, and the second sound collection module 22 is arranged in the receiving cavity.

[0007] Further, the processing device 1 includes a receiving module 11, a filtering module 12, a feature extraction module 13, a control module 14, and a signal generation module 15, where:

[0008] The receiving module 11 is used to receive an audio signal, and the audio signal is generated by the sound collection device 2 according to the outdoor environmental noise and / or the noise conducted by the building wall;

[0009] The filtering module 12 is used to filter the received audio signal to generate a filtered signal;

[0010] The feature extraction module 13 is used to extract the frequency, phase, and amplitude of the filtered signal;

[0011] The control module 14 is configured to generate a cancellation signal according to a preset rule, the frequency, the phase, and the amplitude;

[0012] The signal generation module 15 is configured to generate a cancellation sound wave according to the cancellation signal.

[0013] Further, a mode detector 3 is further included, and the mode detector 3 is configured to detect the state of indoor doors and windows and generate first state information;

[0014] Then, the audio signal is composed of an outdoor environmental noise signal and a building wall conduction noise signal, and the filtered signal is composed of an outdoor environmental noise reduction signal and a building wall conduction noise reduction signal;

[0015] The receiving module 11 is further configured to receive the first state information;

[0016] The filtering module 12 is specifically configured to filter the received outdoor environmental noise signal to generate the outdoor environmental noise reduction signal, and filter the received building wall conduction noise signal to generate the building wall conduction noise reduction signal;

[0017] The feature extraction module 13 is specifically configured to extract the frequency, the phase, and the amplitude of the outdoor environmental noise reduction signal and the building wall conduction noise reduction signal respectively;

[0018] The control module 14 is specifically configured to generate an outdoor sound cancellation signal according to the frequency, the phase, the amplitude of the outdoor environmental noise reduction signal, and a first attenuation coefficient; generate a wall sound cancellation signal according to the frequency, the phase, the amplitude of the building wall conduction noise reduction signal, and a second attenuation coefficient;

[0019] The control module 14 is further configured to select one of the outdoor sound cancellation signal and the wall sound cancellation signal as the cancellation signal according to a preset rule;

[0020] Wherein the first attenuation coefficient is determined according to the first state information.

[0021] Further, the state of the indoor doors and windows at least includes an open window mode, a semi-open window mode, and a closed mode.

[0022] Further, a tuner 4 is further included, and the tuner 4 is arranged at a preset indoor position and is configured to collect the environmental sound at the preset position;

[0023] The tuner 4 includes a third sound collection module 41 for collecting the environmental sound, a processor 42 for determining the relationship between the volume of the environmental sound and a preset value and generating second state information according to the relationship between the volume of the environmental sound and the preset value, and a storage module 43 for storing the preset value;

[0024] Then, the receiving module 11 is further configured to receive the second status information;

[0025] The first attenuation coefficient corresponding to the first status information is determined according to the second status information; the second attenuation coefficient is determined according to the second status information. Further, the preset rule is that when both the outdoor ambient noise and the building wall conduction noise are collected, the wall sound cancellation signal is selected as the cancellation signal. Further, the calibrator 4 further includes a positioning module 44, and the positioning module 44 is configured to determine the current position information of the calibrator 4;

[0026] Then, the storage module 43 is further configured to associate and save the current position information of the calibrator 4 and the associated attenuation coefficient, wherein when the volume of the ambient sound is less than or equal to a preset value, the current first attenuation coefficient and the current second attenuation coefficient are determined as the associated attenuation coefficients.

[0027] Meanwhile, the present invention also provides an active noise cancellation system calibration method, which is applied to the system as described above. The method includes:

[0028] Acquisition step: The outdoor ambient noise is collected by the first sound collection module 21 arranged outdoors, and the building wall conduction noise is collected by the second sound collection module 22 arranged in contact with the wall;

[0029] Generation step: The outdoor sound cancellation signal is generated according to the outdoor ambient noise and the first attenuation coefficient, the wall sound cancellation signal is generated according to the building wall conduction noise and the second attenuation coefficient, and the cancellation sound wave is generated according to the outdoor sound cancellation signal and the wall sound cancellation signal;

[0030] Feedback step: The ambient sound at the preset position is collected by the third sound collection module 41 arranged at the preset position indoors. If the volume of the ambient sound is less than or equal to the preset value, the calibration is stopped; if the volume of the ambient sound is greater than the preset value, the first attenuation coefficient or the second attenuation coefficient is adjusted, and the generation step is executed.

[0031] Still further, the present invention also provides an active noise cancellation system calibration method, which is applied to the system as described above. The method includes:

[0032] Acquisition step: The outdoor ambient noise is collected by the first sound collection module 21 arranged outdoors, and the building wall conduction noise is collected by the second sound collection module 22 arranged in contact with the wall;

[0033] Positioning step: The current position information of the calibrator 4 is obtained through the positioning module 44;

[0034] Generation step: Generate the outdoor noise cancellation signal according to the outdoor environmental noise and the first attenuation coefficient, generate the wall noise cancellation signal according to the building wall-conducted noise and the second attenuation coefficient, and generate the cancellation sound wave according to the outdoor noise cancellation signal and the wall noise cancellation signal;

[0035] Feedback step: Collect the environmental sound at the preset position through the third sound collection module 41 set at the preset indoor position. If the volume of the environmental sound is less than or equal to the preset value, execute the saving step; if the volume of the environmental sound is greater than the preset value, adjust the first attenuation coefficient or the second attenuation coefficient, and execute the generation step;

[0036] Saving step: Associate and save the current position information, the current first attenuation coefficient, and the current second attenuation coefficient.

[0037] The beneficial effects of the present invention are reflected in that, firstly, the present invention simultaneously collects the outdoor environmental noise and the building wall-conducted noise and generates the cancellation sound wave in real time, so that various environmental noises can be actively noise-reduced to improve the experience of indoor personnel. Secondly, by monitoring the states of the doors and windows and formulating corresponding noise reduction coefficients according to the states of the doors and windows, the active noise reduction system can meet various needs of indoor personnel on the basis of ensuring the noise reduction experience. Finally, the present invention can achieve a more accurate active noise reduction effect by collecting the environmental sound at the specified position and adjusting the corresponding noise reduction coefficients in a feedback manner. Description of the Drawings

[0038] Figure 1 Schematic installation diagram of an active noise reduction system provided by the present invention;

[0039] Figure 2 Another schematic installation diagram of an active noise reduction system provided by the present invention;

[0040] Figure 3 Another schematic installation diagram of an active noise reduction system provided by the present invention;

[0041] Figure 4 Another schematic installation diagram of an active noise reduction system provided by the present invention;

[0042] Figure 5 Another schematic installation diagram of an active noise reduction system provided by the present invention;

[0043] Figure 6 Module diagram of an active noise reduction system provided by the present invention;

[0044] Figure 7 Module diagram of the processing device provided by the present invention;

[0045] Figure 8 Another module diagram of the active noise reduction system provided by the present invention;

[0046] Figure 9 Another module diagram of the active noise reduction system provided by the present invention;

[0047] Figure 10 Another module diagram of the active noise reduction system provided by the present invention;

[0048] Figure 11 A flowchart of a method for calibrating an active noise reduction system provided by the present invention;

[0049] Figure 12 Another flowchart of a method for calibrating an active noise reduction system provided by the present invention.

[0050] Reference signs: processing device 1, receiving module 11, filtering module 12, feature extraction module 13, control module 14, signal generation module 15, sound collection device 2, first sound collection module 21, second sound collection module 22, mode detector 3, calibrator 4, third sound collection module 41, processor 42, storage module 43, positioning module 44, window frame 5. Detailed implementation manners

[0051] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] Embodiment 1:

[0053] Refer to Figures 1 to 6 , the active noise reduction system includes a sound collection device 2 and a processing device 1. The sound collection device 2 includes a first sound collection module 21 and a second sound collection module 22. It can be understood that the first sound collection module 21 can be set at any position outside the outdoor wall, door or window frame 5 to collect outdoor environmental noise, and the second sound collection module 22 can be set at any position inside or within the contact wall to collect building wall conduction noise.

[0054] Preferably, as shown in Figure 1 or Figure 3 , in this embodiment, the first sound collection module 21 is set outside the window frame 5, as shown in Figure 4The second sound collection module 22 is attached to the wall and disposed close to the window frame 5, and the processing device 1 is disposed inside the window frame 5. Through this setting method, the system can more accurately obtain the outdoor environmental noise that may affect the interior through the window, thereby improving the effect of active noise reduction. In other embodiments, the wall may be provided with a receiving cavity, and the second sound collection module 22 is disposed in the receiving cavity to more sensitively sense the noise conducted by the building wall, thereby improving the effect of active noise reduction.

[0055] The processing device 1 is configured to generate a cancellation sound wave according to the outdoor environmental noise and / or the noise conducted by the building wall, and the cancellation sound wave is used to reduce the influence of the outdoor environmental noise or the noise conducted by the building wall on the indoor personnel.

[0056] Specifically, as Figure 7 shown, the processing device 1 includes a receiving module 11, a filtering module 12, a feature extraction module 13, a control module 14, and a signal generation module 15. After the sound collection device 2 acquires the outdoor environmental noise and the noise conducted by the building wall, the corresponding noise is converted into corresponding audio signals, that is, the outdoor environmental noise signal and the noise conducted by the building wall signal. The receiving module 11 is connected to the sound collection device 2 by a wired or wireless method, and the wireless connection method may be Bluetooth, wifi, etc., which is not limited herein. After the receiving module 11 receives the outdoor environmental noise signal and the noise conducted by the building wall signal, it transmits them to the filtering module 12. The filtering module 12 filters the received outdoor environmental noise signal and the noise conducted by the building wall signal to generate an outdoor environmental noise reduction signal and a building wall conducted noise reduction signal respectively, that is, a filtered signal; the feature extraction module 13 extracts the frequency, phase, and amplitude of the outdoor environmental noise reduction signal and the building wall conducted noise reduction signal respectively. The control module 14 specifically generates an outdoor noise cancellation signal according to the frequency, phase, and amplitude of the outdoor environmental noise reduction signal; generates a wall noise cancellation signal according to the frequency, phase, and amplitude of the building wall conducted noise reduction signal; and according to a preset rule, the frequency, phase, and amplitude of the outdoor noise cancellation signal, the frequency, phase, and amplitude of the wall noise cancellation signal, and finally generates a cancellation signal, wherein the outdoor environmental noise reduction signal and the outdoor noise cancellation signal have the same frequency, opposite phases, and proportional amplitudes; the building wall conducted noise reduction signal and the wall noise cancellation signal have the same frequency, opposite phases, and proportional amplitudes. The signal generation module 15 generates a cancellation sound wave according to the cancellation signal. At this time, in an ideal state, the cancellation sound wave and the outdoor environmental noise or the noise conducted by the building wall have the same frequency, opposite phases, and proportional amplitudes, so the influence of the noise on the interior can be effectively reduced.

[0057] It should be noted that the outdoor environmental noise is significantly attenuated when transmitted indoors through windows or doors. Similarly, the noise conducted through the building wall is also attenuated when transmitted indoors. Therefore, the attenuation coefficient needs to be considered when generating the outdoor noise cancellation signal and the wall noise cancellation signal. Therefore, the cancellation sound wave is proportional to, rather than the same as, the outdoor environmental noise and the noise conducted through the building wall. Moreover, the above receiving module 11, filtering module 12, feature extraction module 13, and control module 14 can all process the outdoor environmental noise and the noise conducted through the building wall simultaneously, or they can process either one, and this is not limited here.

[0058] It can be understood that in the present invention, the outdoor environmental noise is mainly the external environmental noise such as cars, etc., which generally occurs continuously, and the noise conducted through the building wall is mostly sporadic. Therefore, the preset rule in each embodiment of the present invention is that when the noise conducted through the building wall does not occur, the system only cancels the outdoor environmental noise; when the outdoor environmental noise does not occur, the system only cancels the noise conducted through the building wall; when the noise conducted through the building wall and the outdoor environmental noise occur simultaneously, the system preferentially cancels the noise conducted through the building wall.

[0059] In this embodiment, the processing device 1 can be integrally arranged, or can be physically connected by multiple structures. When the processing device 1 includes multiple physical structures, the installation positions of the remaining modules except the signal generation module 15 have no influence on the system function. In one embodiment, as Figure 5 shown, the receiving module 11, filtering module 12, feature extraction module 13, and control module 14 are integrally arranged and installed outside the window frame 5, and the signal generation module 15 is installed inside the window frame 5. At this time, the signal generation module 15 arranged inside the window frame 5 is closer to the area to be noise-reduced, so as to better achieve the purpose of canceling noise. It should be noted that in this embodiment, the first sound collection module 21 can also be integrally arranged with the receiving module 11, filtering module 12, feature extraction module 13, and control module 14.

[0060] Using this solution, the system simultaneously collects the outdoor environmental noise and the noise conducted through the building wall, and generates a cancellation sound wave in real time, so that it can actively perform noise reduction processing on various environmental noises and thus improve the experience of indoor personnel.

[0061] Embodiment 2:

[0062] Existing soundproof doors and windows generally achieve the soundproofing requirement by using double-layer glass. However, the soundproof doors and windows must ensure that the doors and windows are in a closed state to achieve the soundproofing effect, which is not conducive to indoor ventilation. To ensure a quiet sleeping environment, ventilation must be sacrificed, and ventilation and a quiet sleeping environment are usually what people want to have at the same time.

[0063] To solve the above problems, as Figure 8As shown, on the basis of Embodiment 1, the system further includes a mode detector 3, which is used to detect the state of indoor doors and windows and generate first state information; wherein, the first state information indicates that the doors and windows are in an open window mode, a semi-open window mode, or a closed mode. In other embodiments, when the doors and windows are smart home devices, the mode detector 3 can be integrated with the smart home, and the first state information indicates that the doors and windows are in a closed mode, a micro-ventilation mode, a dust-proof mode, a ventilation mode, etc. It can be understood that the mode detector 3 can be a sensor for detecting doors and windows or the main control processor of the smart home, and is not limited herein.

[0064] When the doors and windows are in different open / closed states, there will be significant differences in the attenuation of outdoor environmental noise and building wall-conducted noise transmitted into the room. Therefore, after the receiving module 11 receives the first state information transmitted by the mode detector 3, it transmits the first state information to the control module 14, and the control module 14 selects the one corresponding to the first state information from multiple pre-stored attenuation coefficients as the first attenuation coefficient. Then, an outdoor noise cancellation signal is generated according to the frequency, phase, amplitude of the outdoor environmental noise cancellation signal and the first attenuation coefficient; a wall noise cancellation signal is generated according to the frequency, phase, amplitude of the building wall-conducted noise cancellation signal and the second attenuation coefficient, where the second attenuation coefficient does not change with the change of the first state information.

[0065] It can be understood that in another embodiment, the control module 14 pre-saves multiple groups of attenuation coefficient groups. Each group of attenuation coefficient groups includes the state of the doors and windows and the outdoor attenuation coefficient. The state of the doors and windows is one of the possible cases of the first state information. In addition to the open, closed, and semi-open states, it can also include the door and window numbers, etc., to apply to an environment with multiple doors and windows. When the determined first state information is obtained, the corresponding attenuation coefficient group can be determined according to the state of the doors and windows, and the outdoor attenuation coefficient in this attenuation coefficient group is the first attenuation coefficient.

[0066] In this embodiment, by monitoring the state of the doors and windows and formulating corresponding noise reduction coefficients, even if the same environmental noise is collected, due to different attenuation coefficients, different amplitude sound waves are emitted. This enables the active noise cancellation system to meet various needs of indoor personnel while ensuring the noise cancellation experience.

[0067] Embodiment 3:

[0068] The sound collection device 2 is arranged outside the room and inside the wall. In addition to passing through the window, the noise reaching a specific position can also enter through other parts such as the door. To ensure the quietness of the specific position, in this embodiment, Figure 9As shown in the figure, on the basis of Embodiment 2, the system further includes a calibrator 4. When in use, the calibrator 4 is set at a preset position indoors to collect the ambient sound at the preset position. It can be understood that if indoor personnel need a quiet sleeping environment, the preset position can be beside the bed, etc. Its specific placement position can be freely moved indoors as needed, and no limitation is made here.

[0069] The calibrator 4 includes a third sound collection module 41 for collecting ambient sound, a processor 42 for determining the relationship between the volume of the ambient sound and the preset value and generating second state information according to the relationship between the volume of the ambient sound and the preset value, and a storage module 43 for storing the preset value;

[0070] It can be understood that the preset value can be any value set manually and stored in the storage module 43. In this embodiment, 35 dB is taken as the preset value. Then the processor 42 obtains the preset value from the storage module 43, judges whether the volume of the ambient sound is greater than 35 dB, and determines the second state information according to whether the volume of the ambient sound is greater than 35 dB. Then the second state information is sent to the processing device 1, and the receiving module 11 of the processing device 1 passes the information to the control module 14 after receiving it.

[0071] When adjusting the outdoor environmental noise, if the second state information shows that the volume of the ambient sound is greater than 35 dB, the first attenuation coefficient is further adjusted until the second state information shows that the volume of the ambient sound is less than or equal to 35 dB. Under different window and door states, there are significant differences in the volume of noise entering the room. Therefore, different attenuation coefficients can be set for different window and door states. In this embodiment, for example: when the first state information shows the window-opening mode, the first attenuation coefficient when the volume of the ambient sound is less than or equal to 35 dB at this time is combined and saved with the corresponding first state information. When the first state information changes from other states to the window-opening mode next time, this first attenuation coefficient can be directly used. It is easy to understand that when the first state information is other window and door states, the corresponding first attenuation coefficients can also be saved, which will not be elaborated here.

[0072] When adjusting the noise conducted by the building wall, if the second state information shows that the volume of the ambient sound is greater than 35 dB, the second attenuation coefficient is further adjusted until the second state information shows that the volume of the ambient sound is less than or equal to 35 dB. As can be seen above, after the adjustment of the second attenuation coefficient is completed, it does not change with the first state information.

[0073] In this embodiment, since the installation position of the sound collection device for the user to collect environmental noise is not a position that needs to be absolutely quiet. For example, in actual applications, our sound collection device is installed on the side facing outside the doors and windows, while the position that needs to be absolutely quiet is beside the bed. Due to the inconsistency of the two positions, it is very difficult to achieve absolute quietness at the bedside position. In this embodiment, an additional calibrator is provided. The calibrator is set at the position that needs to be absolutely quiet, and a third sound collection device is provided on the calibrator. In a certain mode (such as the window-opening mode), the first sound collection device collects the environmental noise outside the window, and the controller emits a cancellation sound wave with the same frequency, opposite direction, and corresponding amplitude as the environmental noise collected by the first sound collection device according to the initial attenuation coefficient; the third sound collection device collects the environmental noise at the position that needs to be absolutely quiet. When the collected environmental noise is greater than the tolerable noise threshold, the control processor adjusts the corresponding attenuation coefficient until the collected environmental noise is less than or equal to the tolerable noise threshold, and then associates and saves the corresponding attenuation coefficient with the corresponding mode.

[0074] During the calibration process, the specific method of adjusting the attenuation coefficient is as follows: Analyzing the sound collected by the third collection module can obtain its phase. By judging whether the phase is the same as the phase of the environmental noise collected by the first sound collection module, if it is the same, it means that the previously set attenuation coefficient is too high and needs to be reduced; on the contrary, it means that the previously set attenuation coefficient is too low and needs to be increased.

[0075] This embodiment can more accurately achieve the effect of active noise reduction by collecting the environmental sounds at the specified position and adjusting the corresponding noise reduction coefficient through feedback. Further, different preset values can be set according to different door and window states to quickly adapt to different user needs.

[0076] Embodiment 4:

[0077] When indoor users use it daily, they will repeatedly adjust the preset position, such as changing between the desk, sofa, and bed every day. If adjustments are made from scratch each time, it will waste a lot of time and lead to a decline in the user experience. Based on this, as Figure 10 shown, on the basis of Embodiment 3, the calibrator 4 in this embodiment further includes a positioning module 44. The positioning module 44 and the calibrator 4 are integrally provided, so the current position information of the calibrator 4 can be obtained in real time or at regular intervals.

[0078] The storage module 43 is also used to associate and save the current position information of the calibrator 4 and the associated attenuation coefficient. Among them, when the volume of the environmental sound is less than or equal to the preset value, the current first attenuation coefficient and the current second attenuation coefficient are determined as the associated attenuation coefficients.

[0079] It can be understood that when the environmental sound volume is less than or equal to the preset value, it indicates that the noise reduction effect of the active noise reduction system has reached the set requirement at this time. At this time, the corresponding first attenuation coefficient and second attenuation coefficient are the optimal or optimal values at the current position, and the first attenuation coefficient, second attenuation coefficient and current position information at this time are associated and saved. When the difference between the position information obtained by the calibrator 4 and the saved position information is less than the specified value for the next time, such as the straight-line distance is less than 5 cm, the active noise reduction system can directly adopt the corresponding first attenuation coefficient and second attenuation coefficient. It should be noted that in this embodiment, when the environmental sound volume is less than or equal to the preset value, the calibrator 4 will obtain the first attenuation coefficient and the second attenuation coefficient sent by the processing device 1.

[0080] In other embodiments, the calibrator 4 will send the comparison result of the current position information, environmental sound volume and preset value to the processing device 1, and the processing device 1 will associate and save the first attenuation coefficient, second attenuation coefficient and current position information at this time. That is, the processing device 1 is further configured to associate and save the current position information of the calibrator 4 and the associated attenuation coefficient, where when the environmental sound volume is less than or equal to the preset value, it is determined that the current first attenuation coefficient and the current second attenuation coefficient are the associated attenuation coefficients. This is not limited here.

[0081] Adopting the technical solution of this embodiment, the user can change the preset position indoors, and can quickly achieve the optimal active noise reduction effect each time after the change, which limits and improves the user experience.

[0082] Embodiment 5:

[0083] The present invention also provides an active noise reduction system calibration method, which is applied to the active noise reduction system as shown in Embodiment 3, as Figure 11 shown, the method includes:

[0084] Acquisition step: Collect the outdoor environmental noise through the first sound collection module 21 arranged outdoors, and collect the building wall conduction noise through the second sound collection module 22 arranged in contact with the wall;

[0085] Generation step: Generate the outdoor sound cancellation signal according to the outdoor environmental noise and the first attenuation coefficient, generate the wall sound cancellation signal according to the building wall conduction noise and the second attenuation coefficient, and generate the cancellation sound wave according to the outdoor sound cancellation signal and the wall sound cancellation signal;

[0086] Feedback step: The ambient sound at the preset position is collected by the third sound collection module 41 set at the preset position in the room. If the volume of the ambient sound is less than or equal to the preset value, the adjustment is stopped; if the volume of the ambient sound is greater than the preset value, the first attenuation coefficient or the second attenuation coefficient is adjusted, and the generation step is executed.

[0087] Before the system is officially operated, it first enters the setting mode, and then starts to execute the steps in this embodiment after executing the setting mode. Specifically, the third sound collection module 41 collects the ambient sound at the preset position. If the volume of the ambient sound is less than or equal to the preset value, it means that the system has been running in a better or optimal state, so the corresponding first attenuation coefficient or the second attenuation coefficient can be maintained without further adjustment; if the volume of the ambient sound is greater than the preset value, the corresponding second state information is generated. After the processing device 1 receives the second state information, it is adjusted based on the current first attenuation coefficient or the second attenuation coefficient to complete the feedback control according to the volume of the ambient sound, and the feedback control is repeated multiple times so that the volume of the ambient sound gradually approaches the preset value until it is less than or equal to the preset value.

[0088] It can be understood that there are many ways to make the ambient sound volume gradually approach a preset value until it is less than or equal to the preset value through feedback control, such as: by increasing the attenuation coefficient in advance, if the ambient sound volume collected by the third sound collection module 41 in the subsequent adjuster 4 is larger than the previous time, it indicates that the attenuation coefficient is adjusted in the opposite way, and the next time it is adjusted by reducing the attenuation coefficient; if the ambient sound volume collected by the third sound collection module 41 in the subsequent adjuster 4 is smaller than the previous time, it indicates that the attenuation coefficient is adjusted correctly, and the adjustment is repeated until the ambient sound volume is less than or equal to the preset value.

[0089] In other embodiments, the environmental sound collected by the third acquisition module 41 can be analyzed to obtain its phase, such as: by judging whether the phase is the same as the phase of the outdoor environmental noise collected by the first sound acquisition module 21, it is judged whether the previous attenuation coefficient is low or high. If the phase is the same, it means that the first attenuation coefficient previously set is high and the first attenuation coefficient needs to be lowered; the adjustment method for the second attenuation coefficient is the same and will not be repeated here. In other embodiments, the adjustment method can further adopt the traversal method, the steepest descent method or training of artificial intelligence neural network, etc. In this embodiment, the steepest descent method is preferred. Compared with the traversal method and artificial intelligence neural network, this method can significantly reduce the amount of calculation and quickly obtain the system extreme value.

[0090] After determining the definite values of the first attenuation coefficient and the second attenuation coefficient through the above solution, stop the calibration, save the first attenuation coefficient and the second attenuation coefficient, and then exit the setting mode. After the system runs, the above first attenuation coefficient and second attenuation coefficient can be directly applied according to the situation.

[0091] By adopting the technical solution of this embodiment, the active noise reduction parameter setting of a specified area can be quickly realized, and the active noise reduction effect can be better guaranteed through feedback control, enhancing the user experience.

[0092] Embodiment 6:

[0093] The present invention further provides a method for calibrating an active noise reduction system, which is applied to the active noise reduction system as shown in Embodiment 4. As Figure 12 shown, the method includes:

[0094] Collection step: Collect the outdoor environmental noise through the first sound collection module 21 arranged outdoors, and collect the building wall conduction noise through the second sound collection module 22 arranged in contact with the wall.

[0095] Positioning step: Obtain the current position information of the calibrator 4 through the positioning module 44.

[0096] Generation step: Generate the outdoor sound cancellation signal according to the outdoor environmental noise and the first attenuation coefficient, generate the wall sound cancellation signal according to the building wall conduction noise and the second attenuation coefficient, and generate the cancellation sound wave according to the outdoor sound cancellation signal and the wall sound cancellation signal.

[0097] Feedback step: Collect the environmental sound at the preset position indoors through the third sound collection module 41 arranged at the preset position indoors. If the volume of the environmental sound is less than or equal to the preset value, execute the saving step; if the volume of the environmental sound is greater than the preset value, adjust the first attenuation coefficient or the second attenuation coefficient, and execute the generation step.

[0098] Saving step: Associate and save the current position information, the current first attenuation coefficient, and the current second attenuation coefficient.

[0099] It can be understood that compared with Embodiment 5, this embodiment adds a positioning step and a saving step. It should be noted that the execution order of the positioning step in the present invention is not limited. The positioning step needs to be executed at least once before the saving step, and it is not limited to be after the collection step or before the generation step.

[0100] After the saving step is completed and the setting mode is exited by using this method, the user can arbitrarily change the position of the tuner 4 and then perform active noise reduction on the corresponding preset positions. After each change of the preset position, the judgment step can be preferentially executed.

[0101] Judgment step: Determine whether the distance between the current preset position and any saved current position information is less than or equal to a specified value. If it is greater, continue with the above steps of this embodiment. If it is less than or equal to, directly use the current position information and the corresponding current first attenuation coefficient and current second attenuation coefficient for active noise reduction.

[0102] By adopting the technical solution of this embodiment, the user can change the preset position indoors, and the optimal effect of active noise reduction can be quickly achieved after each change, which limits and improves the user experience.

[0103] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "center", "top", "bottom", "top part", "bottom part", "inner", "outer", "inner side", "outer side", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present invention. Among them, the "inner side" refers to the internal or enclosed area or space. The "periphery" refers to the area surrounding a specific component or a specific area.

[0104] In the description of the embodiments of the present invention, the terms "first", "second", "third", "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", "third", "fourth" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0105] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "joined", "assembled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0106] In the description of the embodiments of the present invention, specific features, structures, materials, or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0107] In the description of the embodiments of the present invention, it should be understood that "-" and "~" represent the range between two numerical values, and this range includes the endpoints. For example, "A - B" represents a range greater than or equal to A and less than or equal to B. "A ~ B" represents a range greater than or equal to A and less than or equal to B.

[0108] In the description of the embodiments of the present invention, the term "and / or" herein is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0109] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An active noise reduction system, characterized in that, it includes: A sound collection device (2), the sound collection device (2) includes a first sound collection module (21) arranged outdoors for collecting outdoor environmental noise, and a second sound collection module (22) arranged in contact with the building wall for collecting the noise conducted by the building wall; A processing device (1), the processing device (1) is used to generate a cancellation sound wave according to the outdoor environmental noise and the noise conducted by the building wall, and the cancellation sound wave is used to reduce the influence of the outdoor environmental noise or the noise conducted by the building wall on indoor personnel; The processing device (1) includes a receiving module (11), a filtering module (12), a feature extraction module (13), a control module (14) and a signal generation module (15), where: The receiving module (11) is used to receive an audio signal, and the audio signal is generated by the sound collection device (2) according to the outdoor environmental noise and the noise conducted by the building wall; The filtering module (12) is used to filter the received audio signal to generate a filtered signal, and the filtered signal is composed of an outdoor environmental noise reduction signal and a building wall conduction noise reduction signal; It further includes a mode detector (3), and the mode detector (3) is used to detect the state of indoor doors and windows and generate first state information; The receiving module (11) is further used to receive the first state information; The feature extraction module (13) is specifically used to extract the frequency, phase and amplitude of the outdoor environmental noise reduction signal and the building wall conduction noise reduction signal respectively; The control module (14) is specifically used to generate an outdoor sound cancellation signal according to the frequency, phase, amplitude and a first attenuation coefficient of the outdoor environmental noise reduction signal; generate a wall sound cancellation signal according to the frequency, phase, amplitude and a second attenuation coefficient of the building wall conduction noise reduction signal; The control module (14) is further used to select one of the outdoor sound cancellation signal and the wall sound cancellation signal as a cancellation signal according to a preset rule; Wherein the first attenuation coefficient is determined according to the first state information; The signal generation module (15) is used to generate a cancellation sound wave according to the cancellation signal; It further includes a tuner (4), and the tuner (4) is arranged at a preset position indoors for collecting the environmental sound at the preset position; The tuner (4) includes a third sound collection module (41) for collecting the environmental sound, a processor (42) for determining the relationship between the volume of the environmental sound and a preset value and generating second state information according to the relationship between the volume of the environmental sound and the preset value, and a storage module (43) for storing the preset value; Then, the receiving module (11) is further used to receive the second state information; The first attenuation coefficient corresponding to the first state information is determined according to the second state information; the second attenuation coefficient is determined according to the second state information.

2. The active noise reduction system according to claim 1, characterized in that: The wall is provided with a receiving cavity, and the second sound collection module (22) is arranged in the receiving cavity.

3. The active noise reduction system according to claim 1, characterized in that: the states of the indoor doors and windows at least include an open window mode, a semi-open window mode, and a closed mode.

4. The active noise reduction system according to claim 1, characterized in that: the preset rule is that when the outdoor environmental noise and the building wall conduction noise are simultaneously collected, the wall sound absorption signal is selected as the cancellation signal.

5. The active noise reduction system according to claim 4, characterized in that: the calibrator (4) further includes a positioning module (44), and the positioning module (44) is used to determine the current position information of the calibrator (4); then, the storage module (43) is further used to associatively store the current position information of the calibrator (4) and the associated attenuation coefficient, wherein when the volume of the environmental sound is less than or equal to the preset value, the current first attenuation coefficient and the current second attenuation coefficient are determined as the associated attenuation coefficients of the current position information.

6. A method for calibrating an active noise reduction system, characterized in that: applied to the system according to claim 5, and includes: Collection step: The outdoor environmental noise is collected by the first sound collection module (21) arranged outdoors, and the building wall conduction noise is collected by the second sound collection module (22) arranged in contact with the wall; Generation step: The outdoor sound absorption signal is generated according to the outdoor environmental noise and the first attenuation coefficient, the wall sound absorption signal is generated according to the building wall conduction noise and the second attenuation coefficient, and the cancellation sound wave is generated according to the outdoor sound absorption signal and the wall sound absorption signal; Feedback step: The environmental sound at the preset position indoors is collected by the third sound collection module (41) arranged at the preset position indoors. If the volume of the environmental sound is less than or equal to the preset value, the calibration is stopped; if the volume of the environmental sound is greater than the preset value, the first attenuation coefficient or the second attenuation coefficient is adjusted, and the generation step is executed.

7. A method for calibrating an active noise reduction system, characterized in that: applied to the system according to claim 5, and includes: Collection step: The outdoor environmental noise is collected by the first sound collection module (21) arranged outdoors, and the building wall conduction noise is collected by the second sound collection module (22) arranged in contact with the wall; Positioning step: The current position information of the calibrator (4) is obtained through the positioning module (44); Generation step: The outdoor sound absorption signal is generated according to the outdoor environmental noise and the first attenuation coefficient, the wall sound absorption signal is generated according to the building wall conduction noise and the second attenuation coefficient, and the cancellation sound wave is generated according to the outdoor sound absorption signal and the wall sound absorption signal; Feedback step: The environmental sound at the preset position indoors is collected by the third sound collection module (41) arranged at the preset position indoors. If the volume of the environmental sound is less than or equal to the preset value, the saving step is executed; if the volume of the environmental sound is greater than the preset value, the first attenuation coefficient or the second attenuation coefficient is adjusted, and the generation step is executed; Saving step: Correlate and save the current position information, the current first attenuation coefficient, and the current second attenuation coefficient.

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