DISPOSITIVO ACÚSTICO ABERTO E MÉTODO PARA REDUÇÃO DE RUÍDO

Description

1 / 56 “OPEN ACOUSTIC DEVICE AND METHOD FOR NOISE REDUCTION” TECHNICAL FIELD

[01] This invention patent relates to the acoustic field and, in particular, to an open acoustic device. BACKGROUND OF THE INVENTION

[02] An acoustic device allows a user to listen to audio content and make a voice call while ensuring the privacy of the user's interaction content without disturbing those around them. Acoustic devices are generally divided into two types, such as in-ear acoustic devices and open-back acoustic devices. In-ear acoustic devices may have a structure located in a user's ear canal during use, which may block one of the user's ears, and the user may feel uncomfortable wearing the in-ear acoustic device for a long time. Open-back acoustic devices can solve the above problems. Open-back acoustic devices do not block the user's ear, which can be good for prolonged use.However, a microphone configured to acquire external ambient noise and a loudspeaker emitting a noise-reducing acoustic wave in the open acoustic output device may be located close to the user's ear (e.g., a facial area on the front of an auricle) at a certain distance from the user's ear canal, and the ambient noise acquired by the microphone may be directly considered as noise in the user's ear canal for noise reduction, which can often result in a negligible noise reduction effect from the open acoustic output device, thus reducing the user's listening experience.

[03] Therefore, it is desirable to provide an open acoustic device that can allow the user's ears to be unblocked and has good noise reduction capability, thus improving the user's listening experience. SUMMARY

[04] Some embodiments of the present invention provide an open acoustic device. The open acoustic device may include: a structure Petition 870260059494, dated 06 / 18 / 2026, page 11 / 81 2 / 56 of a mounting system configured to secure the acoustic device close to a user's ear without blocking the user's ear canal; a first microphone array configured to acquire ambient noise; a signal processor configured to: determine, based on ambient noise, a primary route transfer function between the first microphone array and the user's ear canal; estimate, based on ambient noise and the primary route transfer function, a noise signal in the user's ear canal; and generate, based on the noise signal in the user's ear canal, a noise reduction signal; and a loudspeaker configured to emit, according to the noise reduction signal, a noise reduction acoustic wave, the noise reduction acoustic wave being configured to eliminate the noise signal in the user's ear canal.

[05] Some embodiments of the present invention provide a method for noise reduction. The method may include: determining, based on the ambient noise acquired by a first array of microphones, a primary route transfer function between the first array of microphones and a user's ear canal; estimating, based on the ambient noise and the primary route transfer function, a noise signal in the user's ear canal; and generating, based on the noise signal in the user's ear canal, a noise reduction signal; and emitting, according to the noise reduction signal, a noise reduction acoustic wave, the noise reduction acoustic wave being configured to eliminate the noise signal in the user's ear canal. BRIEF DESCRIPTION OF THE FIGURES

[06] The present invention is further illustrated in terms of exemplary embodiments. These exemplary embodiments are described in detail with reference to the drawings. These embodiments are non-limiting exemplary embodiments, in which similar reference numerals represent similar structures and in which:

[07] Figure 1 is a structural block diagram illustrating an exemplary open acoustic device according to some embodiments of the present invention; Petition 870260059494, dated 06 / 18 / 2026, p. 12 / 81 3 / 56

[08] Figure 2 is a schematic diagram illustrating the exemplary noise reduction of an open acoustic device according to some embodiments of the present invention;

[09] Figure 3 is a schematic diagram illustrating an exemplary structure of a signal processor according to some embodiments of the present invention;

[10] Figure 4 is a flowchart that illustrates an exemplary process for noise reduction according to some embodiments of the present invention patent;

[11] Figure 5 is a schematic diagram illustrating an exemplary transmission of ambient noise from an open acoustic device according to some embodiments of the present invention;

[12] Figure 6 is a flowchart that illustrates an exemplary process for determining a primary route transfer function between a first array of microphones and a user's ear canal according to some embodiments of the present invention;

[13] Figure 7 is a schematic diagram illustrating the determination of a primary path transfer function from a first microphone array to an ear canal according to some embodiments of the present invention;

[14] Figure 8 is a flowchart that illustrates an exemplary process for a second microphone arrangement that takes part in the work according to some embodiments of the present invention patent;

[15] Figure 9 is another flowchart that illustrates an exemplary process for a second microphone arrangement that takes part in the work according to some embodiments of the present invention patent;

[16] Figure 10 is a flowchart that illustrates an exemplary process for estimating a noise reduction signal according to some embodiments of the present invention patent; Petition 870260059494, dated 06 / 18 / 2026, p. 13 / 81 4 / 56

[17] Figure 11 is a flowchart that illustrates an exemplary process for determining a general secondary path transfer function according to some embodiments of the present invention patent;

[18] Figure 12 is a flowchart that illustrates an exemplary process for determining a first secondary path transfer function according to some embodiments of the present invention patent;

[19] Figure 13A is a schematic diagram illustrating an exemplary distribution of a microphone array according to some embodiments of the present invention;

[20] Figure 13B is a schematic diagram illustrating an exemplary distribution of another microphone arrangement according to some embodiments of the present invention;

[21] Figure 13C is a schematic diagram illustrating an exemplary distribution of yet another arrangement of microphones according to some embodiments of the present invention;

[22] Figure 13D is a schematic diagram illustrating an exemplary distribution of yet another arrangement of microphones according to some embodiments of the present invention;

[23] Figure 14A is a schematic diagram illustrating an exemplary arrangement of a microphone array when a user uses an open acoustic device in accordance with some embodiments of the present invention; and

[24] Figure 14B is a schematic diagram illustrating the exemplary arrangement of another microphone arrangement when a user uses an open acoustic device according to some embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[25] In order to illustrate more clearly the technical solutions related to the embodiments of the present invention patent, a brief introduction of Petition 870260059494, dated 06 / 18 / 2026, p. 14 / 81 5 / 56 drawings relating to the description of embodiments are provided below. Obviously, the drawings described below are only a few examples or embodiments of the present invention. Those skilled in the art, without much creative effort, can apply the present invention to other similar scenarios according to these drawings. Unless obviously obtained from the context or the context illustrates otherwise, the same numeral in the drawings refers to the same structure or operation.

[26] It should be understood that the system, device, unit and / or module used in this document is a method for distinguishing different components, elements, parts, sections or assemblies of different levels. However, if other words can achieve the same purpose, the words may be replaced by other expressions.

[27] As used in the invention patent and appended claims, the singular forms a, an and the include plural referents, unless the content clearly indicates otherwise; plural forms may also include singular forms. In general, the terms “comprise”, “comprises” and / or “comprising”, “include”, “includes” and / or “including”, only solicit the inclusion of steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive listing. Methods or devices may also include other steps or elements.

[28] The flowcharts used in this invention illustrate the operations that the system implements according to the embodiment of this invention. It should be understood that the preceding or following operations may not necessarily be performed in exactly the order. Instead, the operations may be processed in reverse order or simultaneously. In addition, one or more other operations may be added to these processes, or one or more operations may be removed from these processes.

[29] An open acoustic device may include an acoustic device, such as an open earphone, etc. The open acoustic device may attach a loudspeaker to a user's ear fitting via a fastening structure (e.g., an ear hook, a head hook, an earphone, Petition 870260059494, dated 06 / 18 / 2026, page 15 / 81 6 / 56 etc.) without blocking a user's ear canal. When a user wears an open acoustic device, external ambient noise can also be heard by the user, which can make the user's listening experience relatively poor. For example, in a location where the external environment is noisy (e.g., a street, a scenic spot, etc.), when the user wears the open acoustic device to play music, the external ambient noise can enter the user's ear canal directly, causing the user to hear relatively loud ambient noise, which can interfere with the user's music listening experience. As another example, when the user wears the open acoustic device for a call, a microphone may not only pick up the user's own voice but may also pick up ambient noise, making the user's call experience relatively poor.

[30] Based on the above problems, an open acoustic device is described in the embodiments of the present invention. In some embodiments, the acoustic device may include the mounting structure, a first microphone array, a signal processor, and a loudspeaker. The mounting structure may be configured to fix the acoustic device close to a user's ear without blocking the user's ear canal. The first microphone array may be configured to acquire ambient noise. In some embodiments, the signal processor may be configured to determine, based on the ambient noise, a primary route transfer function between the first microphone array and the user's ear canal. The primary route transfer function may refer to a phase frequency response of the ambient noise in the first microphone array transferred to the user's ear canal.Furthermore, the signal processor can estimate, based on ambient noise and the primary route transfer function, a noise signal in the user's ear canal; and generate, based on the noise signal in the user's ear canal, a noise reduction signal. In some embodiments, the loudspeaker can be configured to emit, according to the noise reduction signal, a noise reduction acoustic wave. The noise reduction acoustic wave can be configured to eliminate the noise signal in the user's ear canal. In the open acoustic device provided by the embodiments of the present invention, the first arrangement of... Petition 870260059494, dated 06 / 18 / 2026, page 16 / 81 7 / 56 microphones may include a plurality of microphones. The signal processor can determine the direction of a noise source through the ambient noise acquired by the plurality of microphones. The signal processor can determine the primary route transfer function based on parameter information (e.g., frequency) of the ambient noise, the direction of the noise source, and microphone position information in the first microphone array and in the user's ear canal. The signal processor can estimate the noise signal in the user's ear canal based on parameter information (phase information, frequency information, amplitude information, etc.) of the ambient noise and the primary route transfer function.Furthermore, the signal processor can generate a noise reduction signal based on the estimated noise signal in the user's ear canal, and the loudspeaker can generate a noise reduction acoustic wave based on the noise reduction signal to eliminate noise in the user's ear canal. The open acoustic device provided by the embodiments of the present invention can perform noise reduction for noise in different frequency ranges and exhibit a specific noise reduction effect. For example, in a frequency range of 150 Hz–2000 Hz, a noise reduction depth of the open acoustic device can be 5 dB–25 dB, which can significantly improve the noise reduction effect of the open acoustic device in that frequency range.

[31] Figure 1 is a structural block diagram illustrating an exemplary open acoustic device 100 according to some embodiments of the present invention. As shown in Figure 1, the open acoustic device 100 may include a mounting structure 120, a first microphone array 130, a signal processor 140, and a loudspeaker 150. In some embodiments, the open acoustic device 100 may be mounted near a user's ear via the mounting structure 120 without blocking the user's ear canal. The first microphone array 130 may be configured to acquire ambient noise. The signal processor 140 may be coupled (e.g., electrically connected) with the first microphone array 130 and the loudspeaker 150. The signal processor 140 may receive a signal from the first microphone array 130 and the signal processor 140. Petition 870260059494, dated 06 / 18 / 2026, page 17 / 81 8 / 56 can also send the signal to speaker 150. For example, signal processor 140 can receive and process an electrical signal converted into ambient noise transmitted by the first microphone array 130 to obtain parameter information (e.g., amplitude information, phase information, etc.) from the ambient noise. In some embodiments, the first microphone array 130 may include a plurality of microphones. Signal processor 140 can determine the position of a noise source based on the ambient noise acquired by the plurality of microphones. In some embodiments, signal processor 140 can determine a primary route transfer function between the first microphone array The signal processor 130 and the user's ear canal are based on parameter information (e.g., frequency) of the ambient noise, the position of the noise source, and position information of the first microphone array 130 and the user's ear canal. The signal processor 140 can also estimate, based on the ambient noise and the primary route transfer function, a noise signal in the user's ear canal. The parameter information of a noise reduction signal can correspond to the parameter information of the ambient noise. For example, the amplitude of the noise reduction signal can be similar to the amplitude of the ambient noise. The phase of the noise reduction signal can be approximately opposite to the phase of the ambient noise. The signal processor 140 can transmit the generated noise reduction signal to the loudspeaker 150. The loudspeaker 150 can emit a noise reduction acoustic wave according to the noise reduction signal.The noise-reducing acoustic wave can cancel out ambient noise in the user's ear canal, thus achieving active noise reduction of the open acoustic device 100 and improving the user's listening experience during use of the open acoustic device 100.

[32] The first microphone array 130 can be configured to acquire ambient noise. In some embodiments, ambient noise may refer to a combination of a plurality of external sounds in an environment where the user is located. In some embodiments, ambient noise may include traffic noise, industrial noise, construction noise, social noise or Petition 870260059494, dated 06 / 18 / 2026, p. 18 / 81 9 / 56 similar, or any combination thereof. In some embodiments, traffic noise may include, but is not limited to, driving noise, whistling noise, etc. from a motor vehicle. Industrial noise may include, but is not limited to, operating noise of electrical machinery in a factory, etc. Social living environment noise may include, but is not limited to, crowd gathering noise, entertainment and advertising noise, crowd noise, household appliance noise, etc. In some embodiments, the first microphone array 130 may be placed close to the user's ear canal to acquire ambient noise transmitted to the user's ear canal. The first microphone array 130 may convert an acquired ambient noise signal into an electrical signal and transmit the electrical signal to the signal processor 140 for signal processing. In some embodiments, ambient noise may also include the user's speech.For example, when the open headset 100 is in a non-call state, a sound generated by the user's speech can also be considered as ambient noise. The first microphone array 130 can acquire the sound generated by the user's speech and other ambient noise and convert the sound signal generated by the user's speech and other ambient noise into an electrical signal and transmit the electrical signal to the signal processor 140 for signal processing. In some embodiments, the first microphone array 130 may be distributed in the user's left ear or right ear. In some embodiments, the first microphone array 130 may also be located in both the user's left and right ears. For example, the first microphone array 130 may include a first submicrophone array and a second submicrophone array. The first submicrophone array may be located in the user's left ear.The second array of submicrophones may be located in the user's right ear. The first array of submicrophones and the second array of submicrophones may enter a working state simultaneously, or one of the first and second arrays may enter a working state.

[33] In some modes, ambient noise may include the user's speech. For example, the first microphone array 130 may acquire ambient noise. Petition 870260059494, dated 06 / 18 / 2026, p. 19 / 81 10 / 56 according to a call state of the open acoustic device 100. When the open acoustic device 100 is in a non-call state, the sound generated by the user's speech can also be considered as ambient noise. The first microphone array 130 can acquire the sound generated by the user's speech and other ambient noises. When the open acoustic device 100 is in a call state, the sound generated by the user's speech cannot be considered ambient noise. The first microphone array 130 can acquire ambient noise other than the sound generated by the user's speech. For example, the first microphone array 130 can acquire the noise emitted by a noise source located at a distance (e.g., 0.5 m, 1 m) from the first microphone array 130.

[34] In some embodiments, the first microphone array 130 may include two or more microphones. The first microphone array 130 may include an air-conductor microphone and / or a bone-conductor microphone. In some embodiments, the first microphone array 130 may include two or more air-conductor microphones. For example, when the user listens to music using the open acoustic device 100, the air-conductor microphone may simultaneously obtain the noise from the external environment and the sound generated by the user's speech, convert the obtained external noise and the sound generated by the user's speech into an electrical signal as ambient noise, and transmit the electrical signal to the signal processor 140 for processing. In some embodiments, the first microphone array 130 may also include two or more bone-conductor microphones. In some embodiments, the bone-conductor microphone may be in direct contact with the skin of the user's head.When the user speaks, a vibration signal generated by facial bones or muscles can be transmitted directly to the bone conduction microphone, and the bone conduction microphone can convert the vibration signal into an electrical signal and transmit the electrical signal to the signal processor 140 for signal processing. In some embodiments, the bone conduction microphone may also not be in direct contact with the human body. When the user speaks, the vibration signal generated by the facial bones or muscles can first be transmitted to a receptacle structure and then transmitted from the structure to... Petition 870260059494, dated 06 / 18 / 2026, page 20 / 81 11 / 56 receptacle for the bone conduction microphone. The bone conduction microphone can also convert the vibration signal from the human body into an electrical signal containing voice information. For example, when the user is in call mode, the signal processor 140 can perform noise reduction processing on the sound signal acquired by the air conduction microphone as ambient noise and retain the sound signal acquired by the bone conduction microphone as the voice signal, thus ensuring the quality of the user's speech during the call.

[35] In some embodiments, according to a microphone operating principle, the first microphone array 130 may include a moving coil microphone, a ribbon microphone, a condenser microphone, an electret microphone, an electromagnetic microphone, a carbon particle microphone, or the like, or any combination thereof. In some embodiments, an arrangement of the first microphone array 130 may include a linear arrangement (e.g., a straight line, a curve), a planar arrangement (e.g., a regular and / or irregular shape, such as a cross, a circle, a ring, a polygon, a mesh, etc.), a three-dimensional arrangement (e.g., a cylinder, a sphere, a hemisphere, a polyhedron, etc.), or the like, or any combination thereof. Detailed descriptions of the arrangement of the first microphone array 130 can be found in Figures 13A-13D, Figure 14A, Figure 14B and their respective descriptions.

[36] The signal processor 140 can be configured to determine, based on ambient noise, the primary route transfer function between the first microphone array 130 and the user's ear canal; estimate, based on ambient noise and the primary route transfer function, the noise signal in the user's ear canal; and generate, based on the noise signal in the user's ear canal, the noise reduction signal. The primary route transfer function may refer to a route transfer function from the first microphone array 130 to the user's ear canal. In some embodiments, the signal processor 140 can estimate a direction of a noise source based on ambient noise and determine the primary route transfer function according to parameter information (e.g., a frequency) of the noise. Petition 870260059494, dated 06 / 18 / 2026, page 21 / 81 12 / 56 environmental, the direction of the noise source and the position information of the first microphone array 130 and the user's ear canal. In some embodiments, the signal processor 140 can estimate the noise signal in the user's ear canal based on parameter information (e.g., phase information, frequency information, amplitude information, etc.) of the environmental noise and the primary route transfer function. In addition, the signal processor 140 can generate the noise reduction signal based on the estimated noise signal in the user's ear canal.

[37] In some embodiments, the open acoustic device 100 may also include a second microphone array. The signal processor 140 may estimate, based on the ambient noise acquired by the second microphone array and the noise-reducing acoustic waveform, the noise in the ear canal. In addition, the signal processor 140 may update, based on the sound signal in the ear canal, the noise-reducing signal. In some embodiments, the signal processor 140 may also obtain, based on the sound signal acquired by the second microphone array, the noise-reducing acoustic waveform acquired by the second microphone array.Signal processor 140 can determine, based on the noise-reducing acoustic waveform output by loudspeaker 150 and the noise-reducing acoustic waveform acquired by the second microphone array, the first secondary route transfer function (the first secondary route can be a transmission route of the sound signal from loudspeaker 150 to the second microphone array). Signal processor 140 can determine, based on the first secondary route transfer function through a machine learning model or a predefined model that has been trained, the second secondary route transfer function (the second secondary route can be a transmission route of the sound signal from the second microphone array to the auditory canal).The signal processor 140 can determine, based on the first secondary route transfer function and the second secondary route transfer function, an overall secondary route transfer function (the overall secondary route can be a transmission route of the sound signal from the speaker 150 to the ear canal). The signal processor 140 can estimate, based on the noise signal in the user's ear canal, the noise reduction acoustic waveform. Petition 870260059494, dated 06 / 18 / 2026, page 22 / 81 13 / 56 user's ear canal and generate, based on the noise reduction acoustic waveform in the user's ear canal and the overall secondary route transfer function, the noise reduction signal.

[38] In some embodiments, the 140 signal processor may include a hardware module and a software module. By way of example only, the hardware module may include a digital signal processor (DSP) and an advanced RISC machine (ARM). The software module may include an algorithm module. Further descriptions of the 140 signal processor may be found in Figure 3 and its respective descriptions.

[39] The loudspeaker 150 can be configured to emit, according to the noise reduction signal, the noise reduction acoustic wave. The noise reduction acoustic wave can be configured to reduce or eliminate ambient noise transmitted to the user's ear canal (e.g., a tympanic membrane, a basilar membrane). By way of example only, the signal processor 140 can control the loudspeaker 150 to emit the noise reduction acoustic wave with a similar amplitude and opposite phase to the noise signal in the user's ear canal to cancel the noise signal in the user's ear canal. In some embodiments, when the user uses the open acoustic device 100, the loudspeaker 150 may be located close to the user's ear.In some embodiments, according to a loudspeaker operating principle, the 150 loudspeaker may include an electrodynamic loudspeaker (e.g., a moving coil loudspeaker), a magnetic loudspeaker, an ion loudspeaker, an electrostatic loudspeaker (or a condenser loudspeaker), a piezoelectric loudspeaker, or the like, or any combination thereof. In some embodiments, according to a sound output transmission mode by the loudspeaker, the 150 loudspeaker may include an air-conducting loudspeaker and / or a bone-conducting loudspeaker. In some embodiments, a count of 150 loudspeakers may be one or more. When the count of 150 loudspeakers is one, the 150 loudspeaker may be configured to emit the noise-reducing acoustic wave to eliminate ambient noise and provide sound information that the user needs to hear (e.g., audio from a media device, audio). Petition 870260059494, dated 06 / 18 / 2026, p. 23 / 81 14 / 56 from a remote device for calling) to the user. For example, when the speaker count is 150 and the speaker is an air-conducting speaker, the air-conducting speaker can be configured to emit a noise-reducing acoustic wave to eliminate ambient noise. In this case, the noise-reducing acoustic wave can be an acoustic wave signal (i.e., air vibration). The acoustic wave signal can be transmitted through the air to a target spatial position (e.g., the user's ear canal), and the acoustic wave signal and ambient noise can cancel each other out. At the same time, the air-conducting speaker can also be configured to transmit the sound information that the user needs to hear to the user.As another example, when the speaker count is 150 and the speaker is a bone conduction speaker, the bone conduction speaker can be configured to emit a noise-reducing acoustic wave to eliminate ambient noise. In this case, the noise-reducing acoustic wave can be a vibration signal (e.g., vibration of a speaker box). The vibration signal can be transmitted to the user's basilar membrane through bones or tissues, and the noise-reducing acoustic wave and ambient noise can cancel each other out at the user's basilar membrane. At the same time, the bone conduction speaker can also be configured to transmit the sound information that the user needs to hear to the user.When the speaker count exceeds one (150 speakers), a portion of the 150 speakers can be configured to emit noise-reducing acoustic waves to eliminate ambient noise, and the other portion can be configured to transmit sound information (e.g., audio from a media device, audio from a remote device for calls) that the user needs to hear. For example, when the speaker count exceeds one (150 speakers) and the speaker plurality includes one bone conduction speaker and one air conduction speaker, the air conduction speaker can be configured to emit noise-reducing acoustic waves to reduce or eliminate ambient noise. Compared to the air conduction speaker, the bone conduction speaker can transmit mechanical vibration directly to the user's auditory nerve through the body (such as bones, tissue). Petition 870260059494, dated 06 / 18 / 2026, page 24 / 81 15 / 56 cutaneous, etc.) of the user. In this process, the bone conduction speaker may have relatively little interference from the air conduction microphone that acquires ambient noise.

[40] It should be noted that the loudspeaker 150 may be a stand-alone functional device or may be part of a single device capable of implementing a plurality of functions. By way of example only, the loudspeaker 150 may be integrated and / or formed into one piece with the signal processor 140. In some embodiments, when the count of loudspeakers 150 is more than one, an arrangement of the plurality of loudspeakers 150 may include a linear arrangement (e.g., a straight line, a curve), a planar arrangement (e.g., a regular and / or irregular shape, such as a cross, a mesh, a circle, a ring, a polygon, etc.), a three-dimensional arrangement (e.g., a cylinder, a sphere, a hemisphere, a polyhedron, etc.), or similar, or any combination thereof, which is not limited in this document. In some embodiments, the loudspeaker 150 may be placed in the user's left ear and / or right ear.For example, the 150 speaker may include a first sub-speaker and a second sub-speaker. The first sub-speaker may be located in the user's left ear. The second sub-speaker may be located in the user's right ear. The first sub-speaker and the second sub-speaker may enter the operating state simultaneously, or one of the first sub-speaker and the second sub-speaker may enter the operating state. In some embodiments, the 150 speaker may be a speaker with a directional sound field, whose main lobe may be directed into the user's ear canal.

[41] In some embodiments, in order to ensure consistency of signal acquisition, all microphones in the first microphone array 130 may be located in positions that are not or are less affected by the loudspeaker 150 in the open acoustic device 100. In some embodiments, the loudspeaker 150 may form at least one acoustic dipole set. For example, the front of a diaphragm and the back of a diaphragm of the loudspeaker 150 may be considered as two sound sources and may emit a set of sound signals with approximately opposite phases and similar amplitudes. The two Petition 870260059494, dated 06 / 18 / 2026, p. 25 / 81 16 / 56 Acoustic sources can form an acoustic dipole or may be similar to an acoustic dipole, and the sound radiated outwards may have obvious directivity. Ideally, in one direction of a straight line connecting two point sound sources, the sound radiated by the loudspeaker can be relatively loud, and the sound radiated in other directions can be significantly reduced. The sound radiated by the loudspeaker 150 in a region of a perpendicular midline (or near the perpendicular midline) of the connecting line between the two point sound sources can be the lightest. Therefore, all microphones in the first microphone array 130 can be placed in a region where a sound pressure level from the loudspeaker 150 is minimal, i.e., the region of the perpendicular midline (or near the perpendicular midline) of the connecting line between the two point sound sources.

[42] In some embodiments, the open acoustic device 100 may include the second microphone array 160. In some embodiments, the second microphone array 160 may have two or more microphones. The microphones may include a bone conduction microphone and an air conduction microphone. In some embodiments, the second microphone array 160 may be at least partially different from the first microphone array 130. For example, the microphones in the second microphone array 160 may differ from the microphones in the first microphone array 130 in a count, a type, a position, an arrangement, or the like, or any combination thereof. For example, in some embodiments, the microphone array in the first microphone array 130 may be linear and the microphone array in the second microphone array 160 may be circular.As another example, the microphones in the second 160 microphone array might include only one air-conductor microphone. The first 130 microphone array might include one air-conductor microphone and one bone-conductor microphone. In some embodiments, the microphones in the second 160 microphone array might be any one or more microphones included in the first 130 microphone array. The microphones in the second 160 microphone array might also be independent of the microphones in the first 130 microphone array. The second 160 microphone array might be configured to acquire both ambient noise and waveform. Petition 870260059494, dated 06 / 18 / 2026, page 26 / 81 17 / 56 Noise-reducing acoustics. The ambient noise and the noise-reducing acoustic wave acquired by the second microphone array 160 can be transmitted to the signal processor 140. In some embodiments, the signal processor 140 can update the noise-reducing signal based on the sound signal acquired by the second microphone array 160. In some embodiments, the signal processor 140 can determine, based on the sound signal acquired by the second microphone array 160, the overall secondary route transfer function between the loudspeaker 150 and the user's ear canal and estimate, according to the noise signal in the user's ear canal and the overall secondary route transfer function, the noise-reducing signal.Specific descriptions regarding the update, based on the sound signal acquired by the second microphone array 160, the noise reduction signal can be found in figures 8-12 of the present invention and relevant descriptions thereof.

[43] In some embodiments, the open acoustic device 100 may include a fixation structure 120. The fixation structure 120 may be configured to fix the acoustic device 100 close to the user's ear without blocking the user's ear canal. In some embodiments, the fixation structure 120 may be physically connected (e.g., a snap-fit ​​connection, a screw connection, etc.) to the receptacle structure of the open acoustic device 100. In some embodiments, the receptacle structure of the open acoustic device 100 may be a part of the fixation structure 120. In some embodiments, the fixation structure 120 may include an ear hook, a back hook, an elastic band, an earpiece, etc., so that the open acoustic device 100 may be better fixed close to the user's ear and prevent the open acoustic device 100 from falling out during use.For example, the fastening structure 120 may be an ear hook, and the ear hook may be configured to be worn around the ear. In some embodiments, the ear hook may be a continuous hook and may be stretched elastically to be worn on the user's ear. At the same time, the ear hook may also exert pressure on the user's auricle, so that the open acoustic device 100 may be firmly fixed to a certain position on the user's ear or head. In some embodiments, the ear hook may be a band. Petition 870260059494, dated 06 / 18 / 2026, page 27 / 81 18 / 56 discontinuous. For example, the ear hook may include a rigid portion and a flexible portion. The rigid portion may be made of rigid material (e.g., a plastic, a metal, etc.), and the rigid portion may be attached to the receptacle structure of the acoustic output device 100 by means of a physical connection (e.g., a snap-fit ​​connection, a screw connection, etc.). The flexible portion may be made of an elastic material (e.g., a fabric, a composite material, neoprene, etc.). As another example, the attachment structure may include a neck strap that can be worn around the user's neck / shoulder. Yet another example, the attachment structure 120 may be the earpiece, which may be part of a pair of glasses and may be erected on the user's ear.

[44] In some embodiments, the open acoustic device 100 may include the receptacle structure. The receptacle structure may be configured to carry other components of the open acoustic device 100 (e.g., the first microphone array 130, the signal processor 140, the loudspeaker 150, the second microphone array 160, etc.). In some embodiments, the receptacle structure may be a closed or semi-closed structure with an internal cavity, and other components of the open acoustic device 100 may be arranged within or on the receptacle structure. In some embodiments, a form of the receptacle structure may be a regular or irregular three-dimensional structure, such as a cuboid, a cylinder, a truncated cone, etc. When the user wears the open acoustic device 100, the receptacle structure may be located close to the user's ear.For example, the receptacle structure may be located on a peripheral side (e.g., the front side or the back side) of the user's auricle. As another example, the receptacle structure may be located in the user's ear without blocking or covering the user's ear canal. In some embodiments, the open acoustic device 100 may be a bone conduction headset. At least one side of the receptacle structure may be in contact with the user's skin. An acoustic driver (e.g., a vibrating speaker) in the bone conduction headset may convert an audio signal into mechanical vibration. The mechanical vibration may be transmitted to the user's auditory nerve through the... Petition 870260059494, dated 06 / 18 / 2026, page 28 / 81 19 / 56 user's body and bone structure. In some embodiments, the open acoustic device 100 may be an air-conducting headset. At least one side of the receptacle structure may or may not be in contact with the user's skin. A side wall of the receptacle structure may include at least one sound guide hole. The speaker in the air-conducting headset may convert the audio signal into air-conducting sound. The air-conducting sound may be radiated toward the user's ear through the sound guide hole.

[45] In some embodiments, the open acoustic device 100 may also include one or more sensors. One or more sensors may be electrically connected to other components of the open acoustic device 100 (e.g., the signal processor 140). One or more sensors may be configured to obtain physical position and / or motion information from the open acoustic device 100. By way of example only, one or more sensors may include an inertial measurement unit (IMU), a global positioning system (GPS), a radar, etc. Motion information may include a motion trajectory, a motion direction, a motion speed, a motion acceleration, a motion angular velocity, motion-related time information (e.g., a motion start time, a motion end time), or similar, or any combination thereof.Taking the IMU as an example, the IMU may include a microelectromechanical system (MEMS). The MEMS may include a multi-axis accelerometer, a gyroscope, a magnetometer or similar, or any combination thereof. The IMU may be configured to detect the physical position and / or motion information of the open acoustic device 100 to perform control of the open acoustic device 100 based on the physical position and / or motion information.

[46] In some embodiments, the open acoustic device 100 may include a signal transceiver. The signal transceiver may be electrically connected to other components of the open acoustic device 100 (e.g., the signal processor 140). In some embodiments, the signal transceiver may include Bluetooth, an antenna, etc. The open acoustic device 100 may communicate Petition 870260059494, dated 06 / 18 / 2026, page 29 / 81 20 / 56 with other external devices (e.g., a cell phone, a tablet, a smartwatch) via the signal transceiver. For example, the open acoustic device 100 can communicate wirelessly with other devices via Bluetooth.

[47] In some embodiments, the open acoustic device 100 may also include an interactive module configured to adjust the sound pressure of the noise-reducing acoustic wave. In some embodiments, the interactive module may include a button, a voice assistant, a gesture sensor, etc. The user can adjust the noise reduction mode of the open acoustic device 100 by controlling the interactive module. Specifically, the user can adjust (e.g., enlarge or reduce) the amplitude information of the noise-reducing signal by controlling the interactive module, so as to alter the sound pressure of the noise-reducing acoustic wave emitted by the loudspeaker 150, thus achieving different noise reduction effects. By way of example only, the noise reduction mode may include a strong noise reduction mode, a medium noise reduction mode, a weak noise reduction mode, etc.For example, when the user uses the Open Acoustic Device 100 indoors, the external ambient noise may be light. The user can turn off or adjust the noise reduction mode of the Open Acoustic Device 100 to the low noise reduction mode via the interactive module. As another example, when the user uses the Open Acoustic Device 100 while walking in a public place, such as a street, the user may need to maintain some awareness of their surroundings while listening to an audio signal (e.g., music, voice information) to deal with an emergency. At this point, the user can choose the medium noise reduction mode via the interactive module (e.g., the button or the voice assistant) to preserve ambient noise (such as a siren, an impact sound, a car horn sound, etc.). Yet another example, when the user takes a public vehicle, such as a subway, airplane, etc.The user can select the strong noise reduction mode via the interactive module to further reduce surrounding ambient noise. In some modes, the signal processor 140 can also send immediate information to the open acoustic device 100 or a terminal device (e.g., a mobile phone, a smartwatch, etc.). Petition 870260059494, dated 06 / 18 / 2026, page 30 / 81 21 / 56 which is communicatively connected to the open acoustic device 100 based on an ambient noise intensity range, so as to remind the user to adjust the noise reduction mode.

[48] ​​Figure 2 is a schematic diagram illustrating exemplary noise reduction of an open acoustic device according to some embodiments of the present invention. As shown in Figure 2, x(n) denotes a primary noise signal (an ambient noise signal) acquired by the first microphone array 130. P(z) denotes a primary route by which the primary noise signal spreads from the first microphone array 130 to the ear canal. d(n) denotes a primary noise signal spreading to the second microphone array 160. W(z) denotes an adaptive filter with active noise reduction. y(n) denotes an output signal from the adaptive filter. S(z) denotes a general secondary route of a secondary sound source (a noise-reducing acoustic wave) spreading from the loudspeaker 150 to the ear canal. Y'(n) denotes the sound of the noise-reducing acoustic wave reaching the ear canal via the general secondary route.e(n) denotes the sound in the user's ear canal. One objective of the noise reduction of the open acoustic device 100 may be to minimize the sound e(n) in the ear canal, for example, e(n) = 0. Specific descriptions regarding the first microphone array 130 capturing a signal x(n) can be found in Figure 5, which is not limited here. In some embodiments, the open acoustic device 100 (the signal processor 140) may estimate a noise signal in the user's ear canal according to the primary route P(z) between the first microphone 130 and the user's ear canal and the primary noise signal acquired by the first microphone 130 to generate a corresponding noise reduction signal. The loudspeaker 150 may generate a noise reduction acoustic waveform based on the noise reduction signal.However, due to a certain distance between the loudspeaker 150 and the user's ear canal, the noise-reducing acoustic wave received in the user's ear canal and the noise-reducing acoustic wave from the loudspeaker 150 may be different, which may reduce the noise reduction effect. In some embodiments, the open acoustic device 100 can determine the overall secondary path S(z) between the loudspeaker 150 and the ear canal according to the noise-reducing acoustic wave acquired by it. Petition 870260059494, dated 06 / 18 / 2026, p. 31 / 81 22 / 56 second microphone arrangement 160 and ambient noise, so that determine the noise reduction signal according to the general secondary route S(z) to increase the noise reduction capacity of the loudspeaker noise reduction acoustic wave 150 received in the user's ear canal, so that the sound e(n) in the user's ear canal is reduced to a minimum.

[49] It should be noted that the description above of Figure 1 and Figure 2 is provided for illustrative purposes only and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of variations and modifications may be made in accordance with the teachings of the present invention. However, such variations and modifications do not depart from the scope of the present invention. For example, one or more components in the open acoustic device 100 (e.g., a fixing structure, etc.) may be omitted. In some embodiments, a component may be replaced by other components that can implement similar functions. For example, in some embodiments, the open acoustic device 100 may not include the fixing structure. A receptacle structure of the open acoustic device 100 may be a receptacle structure with a shape corresponding to the shape of the user's ear.The shape of the receptacle structure may include a circular ring, an oval, a polygonal shape (regular or irregular), a U-shape, a V-shape, a semicircle, etc., and the receptacle structure may be anchored directly into the user's ear. In some embodiments, a component may be divided into a plurality of subcomponents or a plurality of components may be merged into a single component.

[50] Figure 3 is a schematic diagram illustrating an exemplary structure of a signal processor according to some embodiments of the present invention. As shown in Figure 3, the signal processor 140 may include an analog-to-digital conversion unit 210, a noise estimation unit 220, an amplitude and phase compensation unit 230 and a digital-to-analog conversion unit 240.

[51] In some forms, the analog-to-digital conversion unit Petition 870260059494, dated 06 / 18 / 2026, p. 32 / 81 23 / 56 210 can be configured to convert a signal input from the first microphone array 130 or the second microphone array 160 into a digital signal. For example, the first microphone array 130 can acquire ambient noise, convert the acquired ambient noise into an electrical signal, and transmit the electrical signal to the signal processor 140. After receiving the electrical signal from the ambient noise sent by the first microphone array 130, the analog-to-digital conversion unit 210 can convert the electrical signal into a digital signal. In some embodiments, the analog-to-digital conversion unit 210 can be electrically connected to the first microphone array 130 and also electrically connected to other components of the signal processor 140 (for example, the noise estimation unit 220).Furthermore, the analog-to-digital conversion unit 210 can transmit the converted digital signal of ambient noise to the noise estimation unit 220.

[52] In some embodiments, the noise estimation unit 220 can be configured to estimate the ambient noise of the received digital signal from the ambient noise. For example, the noise estimation unit 220 can estimate the relevant parameter of the ambient noise at a target spatial position (e.g., a user's ear canal) of the received digital signal from the ambient noise. By way of example only, the parameters may include a direction of a noise feature, an amplitude, a phase, etc., at the target spatial position (e.g., the user's ear canal), or any combination thereof.In some embodiments, the noise estimation unit 220 can estimate the direction of the noise source according to the digital signal of the ambient noise received by the first microphone array 130, determine a primary route transfer function according to the ambient noise (e.g., a frequency), the direction of the noise source, and position information between the first microphone array 130 and the user's ear canal, and estimate a noise signal in the user's ear canal based on the ambient noise and the primary route transfer function. In some embodiments, the noise estimation unit 220 can estimate the noise in the user's ear canal according to the ambient noise acquired by the second microphone array 160 and the noise-reducing acoustic waveform, and update a noise-reducing signal based on the sound signal in the canal. Petition 870260059494, dated 06 / 18 / 2026, p. 33 / 81 24 / 56 user's auditory canal. In some embodiments, the noise estimation unit 220 can determine an overall secondary route transfer function between the loudspeaker 150 and the user's auditory canal based on a sound signal acquired by the second microphone array 160 and update the noise reduction signal according to the noise signal in the user's auditory canal and the overall secondary route transfer function. In some embodiments, the noise estimation unit 220 can also be configured to estimate a sound field at the target spatial position (e.g., the user's auditory canal) using the first microphone array 130. In some embodiments, the noise estimation unit 220 can be electrically connected to other signal processor components 140 (e.g., the amplitude and phase compensation unit 230).Furthermore, the noise estimation unit 220 can transmit the estimated parameters related to ambient noise and the sound field at the target spatial position to the amplitude and phase compensation unit 230.

[53] In some embodiments, the amplitude and phase compensation unit 230 can be configured to compensate for estimated parameters related to ambient noise according to the sound field at the target spatial position. For example, the amplitude and phase compensation unit 230 can compensate for the amplitude and phase of ambient noise according to the sound field in the user's ear canal. The signal processor 140 can generate a digital noise reduction signal based on the ambient noise compensated by the amplitude and phase compensation unit 230. In some embodiments, the amplitude and phase compensation unit 230 can adjust the amplitude of the ambient noise and perform reverse compensation on the phase of the ambient noise. The signal processor 140 can generate a digital noise reduction signal based on the ambient noise compensated by the amplitude and phase compensation unit 230.The amplitude of the digital noise reduction signal can be similar to the amplitude of the digital signal corresponding to the ambient noise. The phase of the digital noise reduction signal can be approximately opposite to the phase of the digital signal corresponding to the ambient noise. In some embodiments, the amplitude and phase compensation unit 230 can be electrically connected to others. Petition 870260059494, dated 06 / 18 / 2026, page 34 / 81 25 / 56 signal processor components 140 (e.g., the digital-to-analog conversion unit 240). In addition, the amplitude and phase compensation unit 230 can transmit the digital noise reduction signal to the digital-to-analog conversion unit 240.

[54] In some embodiments, the digital-to-analog converter unit 240 can be configured to convert the digital noise reduction signal into an analog signal to obtain the noise reduction signal (e.g., the electrical signal). By way of example only, the digital-to-analog converter unit 240 may include pulse width modulation (PMW). In some embodiments, the digital-to-analog converter unit 240 may be connected to other components of the open acoustic device 100 (e.g., the loudspeaker 150). Furthermore, the digital-to-analog converter unit 240 may transmit the noise reduction signal to the loudspeaker 150.

[55] In some embodiments, the signal processor 140 may include a signal amplification unit 250. The signal amplification unit 250 may be configured to amplify an input signal. For example, the signal amplification unit 250 may amplify the signal input by the first microphone array 130. By way of example only, when the open acoustic device 100 is in a call state, the signal amplification unit 250 may be configured to amplify speech from the user input by the first microphone array 130. In some embodiments, the signal amplification unit 250 may be electrically connected to other components of the open acoustic device 100 or the signal processor 140 (for example, the first microphone array 130, the noise estimation unit 220 and the amplitude and phase compensation unit 230).

[56] It should be noted that the description above Figure 3 is provided for illustrative purposes only and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of variations and modifications may be made in accordance with the teachings of the present invention. In some embodiments, one or more components in the signal processor 140 (for example, the signal amplification unit 250) Petition 870260059494, dated 06 / 18 / 2026, page 35 / 81 26 / 56 may be omitted. In some embodiments, a component in the signal processor 140 may be divided into a plurality of subcomponents, or a plurality of components may be merged into a single component. For example, the noise estimation unit 220 and the amplitude and phase compensation unit 230 may be defined as a component to perform the functions of the noise estimation unit 220 and the amplitude and phase compensation unit 230. However, these variations and modifications do not depart from the scope of the present invention.

[57] Figure 4 is a flowchart illustrating an exemplary process for noise reduction according to some embodiments of the present invention. As shown in Figure 4, process 400 may include the following operations.

[58] In 410, ambient noise can be acquired.

[59] In some modes, the operation can be performed by the first microphone array 130.

[60] According to the descriptions above in Figures 1-2, environmental noise can refer to a combination of various external sounds (e.g., traffic noise, industrial noise, construction noise, social noise) in an environment where the user is located. In some embodiments, the first microphone array 130 may be located near the user's ear canal. When environmental noise is transmitted to the first microphone array 130, each microphone in the first microphone array 130 can convert an acquired environmental noise signal respectively into an electrical signal and transmit the electrical signal to the signal processor 140 for signal processing.

[61] In 420, a primary route transfer function between the first microphone array and the user's ear canal can be determined based on ambient noise.

[62] In some modes, the operation can be performed by the signal processor 140. Petition 870260059494, dated 06 / 18 / 2026, page 36 / 81 27 / 56

[63] The first microphone array 130 can convert acquired ambient noise from different directions and types into an electrical signal and transmit the electrical signal to the signal processor 140. The signal processor 140 can analyze the electrical signal corresponding to the ambient noise, thus calculating the primary route transfer function from the first microphone array 130 to the user's ear canal. The primary route transfer function may include a phase frequency response of the ambient noise transmitted from the first microphone array 130 to the user's ear canal. The signal processor 140 can determine the noise in the user's ear canal according to the ambient noise acquired by the first microphone array 130 and the primary route transfer function. For an example of the primary route transfer function, see the description in Figure 5.Figure 5 is a schematic diagram illustrating an exemplary transmission of ambient noise from an open acoustic device according to some embodiments of the present invention. As shown in Figure 5, in some embodiments, the first microphone array 130 may have two or more microphones. When the user wears the open acoustic device, the open acoustic device 100 may be located near one of the user's ears (e.g., a facial region in front of the user's auricle, in the user's auricle, or behind the user's auricle, etc.). Consequently, at this time, the two or more microphones in the first microphone array 130 may be located near the user's ear (e.g., the facial region in front of the user's auricle, in the user's auricle, or behind the user's auricle, etc.), and the first microphone array 130 may acquire ambient noise from various directions.Figures 1, 2, and 3 shown in Figure 5 represent three microphones in the first microphone array 130. The black circles represent the ear canal, and the solid line arrows represent the ambient noise signal from different directions. A dashed arrow represents a primary route transfer function from the first microphone array 130 to the ear canal. It can be seen from Figure 5 that, even though the signals from two ambient noise signals (shown in Figure 5, signal 1 and signal 2) from different directions are the same when reaching microphone 3, the signals from two ambient noise signals from different directions may be different when reaching the... Petition 870260059494, dated 06 / 18 / 2026, page 37 / 81 28 / 56 ear canal. For example, the phases of signal 1 and signal 2 may be different in the ear canal. By determining the primary route transfer function between the first microphone array 130 and the user's ear canal, the ambient noise acquired by the first microphone array 130 can be converted into noise at an opening in the user's ear canal, so as to more accurately obtain noise reduction at the opening in the user's ear canal. Specific descriptions regarding the determination of the primary route transfer function can be found in Figure 6, Figure 7 and their respective descriptions.

[64] In 430, a noise signal in the user's ear canal can be estimated based on ambient noise and the primary route transfer function.

[65] In some modes, the operation can be performed by the signal processor 140.

[66] The noise signal in the user's ear canal may refer to a sound field of ambient noise in the user's ear canal. In some embodiments, the sound field in the ear canal may refer to a distribution and a change (e.g., a change over time, a change with position) of an acoustic wave at or near the ear canal opening. A physical quantity of the sound field may include a sound pressure, a sound audio, a sound amplitude, a sound phase, a vibration velocity of the sound source, a media density (e.g., air), etc. In some embodiments, the physical quantity of the sound field may be a function of position and time.Since the open acoustic output device is located near the user's ear canal without blocking it, a transmission route for external ambient noise can be considered whereby the external ambient noise is first acquired by a microphone in the first microphone array 130, and then transmitted to the user's ear canal. In order to accurately determine the noise signal in the user's ear canal, in some embodiments, the noise signal in the user's ear canal can be estimated through the ambient noise acquired by the first microphone array 130 and the primary route transfer function. Specifically, the signal processor 140 can acquire relevant parameters (e.g., amplitude, phase, etc.). Petition 870260059494, dated 06 / 18 / 2026, page 38 / 81 29 / 56 etc.) of ambient noise according to the first microphone array 130 and estimate the noise signal at the ear canal opening according to the primary route transfer function of the first microphone array 130 to the ear canal.

[67] In 440, a noise reduction signal can be generated based on the noise signal in the user's ear canal.

[68] In some modes, the operation can be performed by the signal processor 140.

[69] In some embodiments, the signal processor 140 can generate the noise reduction signal based on the noise signal in the ear canal obtained in operation 430. In order to ensure the noise reduction effect of the open acoustic device, in some embodiments, the phase of the noise reduction signal can be opposite or approximately opposite to the phase of the noise signal in the user's ear canal. The amplitude of the noise reduction signal can be equal to or similar to the amplitude of the noise in the ear canal opening, so that the noise reduction acoustic wave output by the loudspeaker based on the noise reduction signal can cancel ambient noise in the user's ear canal. In some embodiments, the user can also manually adjust the parameter information (e.g., phase, amplitude, etc.) of the noise reduction signal according to a usage scenario.By way of example only, in some applications, the absolute value of a phase difference between the phase of the noise-canceling signal and the phase of the noise signal in the ear canal may be within a predefined phase range. In some applications, the predefined phase range may be 90 degrees–180 degrees. The absolute value of the phase difference between the phase of the noise-canceling signal and the phase of the noise signal in the ear canal can be adjusted within the range according to the user's needs. For example, when the user does not want to be disturbed by ambient sound, the absolute value of the phase difference may be a relatively large value, such as 180 degrees, i.e., the phase of the noise-canceling signal may be opposite to the phase of the noise at the ear canal opening. As another example, when the user wishes to be sensitive to the surrounding environment, for example, when the user is walking through it. Petition 870260059494, dated 06 / 18 / 2026, page 39 / 81 30 / 56 on a road or while cycling, the absolute value of the phase difference can be a relatively small value, such as 90 degrees. It should be noted that the more the user wishes to receive sound from the surrounding environment, the closer the absolute value of the phase difference can be to 90 degrees. When the absolute value of the phase difference is close to 90 degrees, the cancellation and overlapping effects between the noise-reducing signal and the noise signal in the user's ear canal can be relatively weak, so the user can receive more sound from the surrounding environment, and it cannot increase the volume of the noise signal heard by the user's ear canal. The more sound from the surrounding environment the user wishes to receive, the closer the absolute value of the phase difference can be to 180 degrees.In some applications, when the phase of the noise-canceling signal and the phase of the noise at the ear canal opening meet a certain condition (for example, the phases may be opposite), a difference between the amplitude of the noise at the ear canal opening and the amplitude of the noise-canceling signal may be within a predefined amplitude range. For example, when the user does not want to be disturbed by ambient noise, the amplitude difference may be a relatively small value, for example, 0 dB, i.e., the amplitude of the noise-canceling signal may be equal to the amplitude of the noise at the ear canal opening. As another example, when the user wishes to be sensitive to the surrounding environment, the amplitude difference may be a relatively large value, for example, similar to the amplitude of the noise at the ear canal opening.It should be noted that the more ambient sound the user wishes to receive, the closer the amplitude difference can be to the amplitude of the noise in the ear canal. The less ambient sound the user wishes to receive, the closer the amplitude difference can be to 0 dB.

[70] At 450, a noise-reducing acoustic wave can be emitted in accordance with the noise-reducing signal.

[71] In some modes, the operation can be performed by speaker 150.

[72] In some embodiments, the 150 loudspeaker can convert the noise reduction signal (e.g., the electrical signal) based on a component of Petition 870260059494, dated 06 / 18 / 2026, pp. 40 / 81 31 / 56 Vibration in the loudspeaker 150 in the noise-reducing acoustic wave. The noise-reducing acoustic wave can cancel out the ambient noise in the user's ear canal. For example, when the ambient noise is the first ambient noise, the ambient noise can be a sound field of the first ambient noise in the user's ear canal. As another example, when there is a plurality of ambient noise, the ambient noise can include the first ambient noise and a second environmental noise. The ambient noise can refer to a sound field of the first environmental noise and the second environmental noise in the user's ear canal. In some embodiments, the loudspeaker 150 can emit a target signal corresponding to the sound field in the user's ear canal based on the noise-reducing signal.In some embodiments, when the noise in the ear canal is a plurality of ambient noise, the loudspeaker 150 can emit noise-reducing acoustic waves corresponding to the plurality of ambient noise based on the noise-reducing signal. For example, the plurality of ambient noise may include the first ambient noise and the second ambient noise. The loudspeaker 150 can emit a first noise-reducing acoustic wave with an approximately opposite phase and an amplitude similar to the noise of the first ambient noise, and a second noise-reducing acoustic wave with an approximately opposite phase and an amplitude similar to the noise of the second ambient noise to cancel the ambient noise. In some embodiments, when the loudspeaker 150 is an air-conducted loudspeaker, a position where the noise-reducing acoustic wave cancels the ambient noise may be a position close to the ear canal.The distance between the position near the ear canal and the user's ear canal may be small. The noise near the ear canal opening can be considered approximately the same as the noise at the user's ear canal position. Therefore, the noise-reducing acoustic wave and the noise near the ear canal can cancel each other out, which can be approximated so that the ambient noise transmitted to the user's ear canal is eliminated, thus achieving active noise reduction of the open acoustic device 100. In some embodiments, when the loudspeaker 150 is a bone conduction loudspeaker, a position where the noise-reducing acoustic wave and ambient noise can be cancelled may be a basilar membrane. The noise-reducing acoustic wave and the noise. Petition 870260059494, dated 06 / 18 / 2026, p. 41 / 81 32 / 56 environmental factors can be cancelled in the user's basilar membrane, thus achieving active noise reduction of the open acoustic device 100.

[73] In some embodiments, the signal processor 140 can also update the noise reduction signal according to an input manually entered by the user. For example, when the user uses the open acoustic device 100 in a relatively noisy external environment, the user's listening experience effect is not ideal, the user can manually adjust the parameter information (e.g., frequency information, phase information, amplitude information) of the noise reduction signal according to the user's listening effect.As another example, in a process of using the Open Acoustic Device 100 by a special user (e.g., a user with hearing impairment or an elderly user), the hearing ability of the special user may be different from that of a typical user, and the noise reduction signal generated by the Open Acoustic Device 100 may not meet the special user's needs, resulting in a poor listening experience for the special user. In this case, a multiple adjustment of the noise reduction signal parameter information can be preset, and the special user can adjust the noise reduction signal according to their own hearing effects and the preset multiple adjustment of the noise reduction signal parameter information, thus updating the noise reduction signal to improve the special user's listening experience.In some modes, users can manually adjust the noise reduction signal via a button on the open acoustic device 100. In other modes, the user can adjust the noise reduction signal via a terminal device. Specifically, the parameter information of the noise reduction signal suggested to the user can be displayed on the open acoustic device 100 or on an external device (e.g., a mobile phone, a tablet, a computer) communicating with the open acoustic device 100. The user can adjust the parameter information according to their own listening experience.

[74] It should be noted that the above description of process 400 is merely Petition 870260059494, dated 06 / 18 / 2026, page 42 / 81 Figure 33 / 56 is provided for illustrative purposes only and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of modifications and variations can be made to process 400 under the teachings of the present invention. For example, an operation can be augmented, omitted, or merged in process 400. As another example, signal processing (e.g., filtering, etc.) can also be performed on ambient noise. However, these modifications and variations do not depart from the scope of the present invention.

[75] However, these variations and modifications do not depart from the scope of the present invention patent. In some embodiments, operation 420 can be implemented through the process in figure 6. As shown in figure 6, process 600 may include the following operations.

[76] In 610, the direction of a noise source can be estimated based on ambient noise.

[77] In some modes, the operation can be performed by the signal processor 140.

[78] The first microphone array 130 can convert acquired ambient noise with different directions and different types into an electrical signal, and the electrical signal can be transmitted to the signal processor 140. The signal processor 140 can analyze the electrical signal corresponding to the ambient noise and estimate the direction of the noise source by means of a noise positioning algorithm.

[79] In some embodiments, the noise positioning algorithm may include a beamforming algorithm, a super-resolution spatial spectrum estimation algorithm, an arrival time difference algorithm (also referred to as a delay estimation algorithm), or similar, or any combination thereof. The beamforming algorithm may be a way of positioning a sound source based on a controlled beam formed based on a maximum output power. Just as an example, the beamforming algorithm may include a direction response power phase transform (SPR-PHAT) algorithm, a Petition 870260059494, dated 06 / 18 / 2026, p. 43 / 81 34 / 56 delay-summing beamforming algorithm, a differential microphone algorithm, a generalized side-lobe canceller (GSC) algorithm, a minimum variance distortion response (MVDR) algorithm, etc. The super-resolution spatial spectrum estimation algorithm may include an autoregression (AR) model, a minimum variance (MV) spectrum estimation, and eigenvalue decomposition form (e.g., a multiple signal classification algorithm (MUSIC), etc. These methods can calculate a related array of a spatial spectrum by obtaining the ambient noise acquired by the microphone array and effectively estimate the direction of the ambient noise source. The time-of-arrival difference algorithm can be performed first to estimate a time-of-arrival difference of the sound and obtain the TDOA of the sound between microphones in the microphone array.The direction of the ambient noise source can be further determined in combination with the spatial position of the microphone array, known using the TDOA (Time-of-Air Optics) of the sound.

[80] For example, the delay estimation algorithm can determine the position of the noise source by calculating the time difference of the ambient noise signal transmitted to the different microphones in the microphone array and determining a geometric relationship. As another example, the SPR-PHAT algorithm can perform beamforming in a direction from each noise source. A direction with stronger beam energy can be considered approximately as the direction of the noise source. Yet another example, the MUSIC algorithm can obtain a subspace of the ambient noise signal by decomposing a covariance array of the ambient noise signal acquired by the microphone array, thus separating the direction of the ambient noise.As another example, in some embodiments, the 140 signal processor can divide the acquired ambient noise into a plurality of frequency bands according to a specific frequency bandwidth (e.g., every 500 Hz as a frequency band). Each frequency band can correspond to a different frequency range, respectively, and determine the ambient noise corresponding to the frequency band in at least one frequency band. For example, the 140 signal processor can obtain parameter information from the ambient noise corresponding to each frequency band by performing analysis of... Petition 870260059494, dated 06 / 18 / 2026, p. 44 / 81 35 / 56 signal in the frequency band divided by ambient noise. As another example, the 140 signal processor can determine the ambient noise corresponding to each frequency band using a noise positioning algorithm.

[81] In order to illustrate more clearly a principle of noise source positioning, the beamforming algorithm can be taken as an example to describe how noise source positioning is performed in detail. Taking the microphone array as an example of a linear array, the noise source can be a far-field sound source. At this point, an acoustic wave incident from the noise source to the microphone array can be considered parallel. In a parallel sound field, when an angle of incidence of the acoustic wave incident from the noise source is perpendicular to a microphone plane in the microphone array (e.g., the first microphone array 130 or the second microphone array 160), the incident acoustic wave can reach each microphone in the microphone array (e.g., the first microphone array 130 or the second microphone array 160) simultaneously.In some embodiments, when the angle of incidence of the incident acoustic wave from the noise source in the parallel sound field is not perpendicular to the plane of microphones in the microphone array (e.g., in the first microphone array 130° or the second microphone array 160°), the incident acoustic wave may reach each microphone in the microphone array (e.g., the first microphone array 130° or the second microphone array 160°) with a delay, which can be determined by the angle of incidence. In some embodiments, for different angles of incidence, the intensities of the noise waveform after superposition may be different. For example, when the angle of incidence is 0°, the intensity of the noise signal may be relatively weak. When the angle of incidence is 45°, the intensity of the noise signal may be the strongest.When the angles of incidence are different, the superimposed waveform intensities of the noise waveforms may be different, so the microphone array may have polarity, thus obtaining a polarity diagram of the microphone array. In some embodiments, the microphone array (e.g. Petition 870260059494, dated 06 / 18 / 2026, p. 45 / 81 36 / 56 For example, the first microphone array (130) or the second microphone array (160) could be a directional array. The directivity of the directional array can be achieved by a time-domain algorithm or a frequency-domain phase-delay algorithm, for example, delay, superposition, etc. In some modes, by controlling different delays, the directivity of different directions can be achieved. In some modes, the directivity of the directional array is controllable, which can be equivalent to a spatial filter first dividing a noise positioning region into grids, delaying each microphone in the time domain through a delay time from each grid point, and finally superimposing the time-domain delay of each microphone to calculate a sound pressure from each grid, thus obtaining a relative sound pressure from each grid and finally performing the positioning of the noise source.

[82] In 620, the primary route transfer function can be determined according to the ambient noise, the direction of the noise source and the position information of the first microphone array 130 and the user's ear canal.

[83] In some modes, the operation can be performed by the signal processor 140.

[84] In some embodiments, the position information of the first microphone array 130 and the user's ear canal may refer to a distance between any microphone in the microphone array 130 and the user's ear canal. For example, the first microphone array 130 may include a first microphone and a second microphone. The position information of the first microphone array 130 and the user's ear canal may refer to a distance between the first microphone and the user's ear canal. The first microphone may be a microphone closer to the user's ear canal or a microphone in a different position.In some embodiments, determining the primary route transfer function based on ambient noise, the direction of the noise source, and the position information of the first microphone array 130 and the user's ear canal may include determining the primary route transfer function based on the frequency of the ambient noise, the direction of the noise source, and... Petition 870260059494, dated 06 / 18 / 2026, p. 46 / 81 37 / 56 in the distance between the first microphone array and the user's ear canal. Specific descriptions regarding the determination of the primary route transfer function can be found in Figure 7 and its respective descriptions. Figure 7 is a schematic diagram illustrating the determination of a primary route transfer function from a first microphone array to an ear canal according to some embodiments of the present invention. As shown in Figure 7, the first microphone array 130 may include a microphone 710, a microphone 720, and a microphone 730. The microphone 710, the microphone 720, and the microphone 730 may be located near the user's ear canal. A distance between the first microphone array 130 and the ear canal opening can be considered as a distance d between the microphone 710 and the user's ear canal opening.An angle of a transmission direction X of the ambient noise relative to a connecting line between microphone 710 and the ear canal. A frequency of the ambient noise sound signal acquired by microphone 710 in the first microphone array 130. An amplitude of the ambient noise sound signal acquired by microphone 710 in the first microphone array 130 is A. The transfer function from microphone 710 in the first microphone array 130 to the ear canal opening can be expressed as P(z)=A. The primary route transfer function can be calculated based on information such as the direction of the ambient noise source, etc., through microphone 710 in the first microphone array 130 here. It should be noted that, in a process of calculating the primary route transfer function, one is not limited to microphone 710 in the first microphone array 130 and the noise signal acquired by microphone 710.The 720 microphone or the 730 microphone, and the noise signal acquired by the 720 microphone or the 730 microphone, can also be applied.

[85] It should be noted that the above description of process 600 is merely provided for illustrative purposes and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of modifications and variations may be made to process 600 in accordance with the teachings of the present invention. However, such modifications and variations do not depart from the scope of the present invention. Petition 870260059494, dated 06 / 18 / 2026, page 47 / 81 38 / 56

[86] In some embodiments, after the noise-reducing acoustic wave output by the loudspeaker based on the noise-reducing signal is transmitted to the user's ear canal opening, the parameter information (e.g., phase information, amplitude information, etc.) of the noise-reducing acoustic wave may change, so that the noise-reducing acoustic wave may not completely cancel the noise at the user's ear canal opening. In order to improve the noise-reducing effect of the open acoustic device, in some embodiments, the open acoustic device may also include a second microphone array. The second microphone array may acquire ambient noise and the noise-reducing acoustic wave. The signal processor may be configured to estimate, based on the ambient noise acquired by the second microphone array and the noise-reducing acoustic wave, noise at a first spatial position.The signal processor can also be configured to update the noise reduction signal based on the noise at the first spatial position. The first spatial position can be considered equivalently as the user's ear canal or a position close to the user's ear canal. In some embodiments, the first spatial position may be closer to the user's ear canal than any microphone in the second microphone array.

[87] Figure 8 is a flowchart illustrating an exemplary process for a second arrangement of microphones 160 participating in the work according to some embodiments of the present invention. As shown in Figure 8, the process 800 may include the following operations.

[88] In 810, the noise at a first spatial position can be estimated based on the ambient noise acquired by the second microphone array 160 and the noise reduction acoustic waveform.

[89] In some modes, the operation can be performed by the signal processor 140.

[90] In some modalities, the first spatial position may refer to a spatial position with a specific distance from the user's ear canal. The first spatial position may be closer to the user's ear canal than Petition 870260059494, dated 06 / 18 / 2026, pp. 48 / 81 39 / 56 that any microphone in the second 160 microphone array. The specific distance here can be a fixed distance, for example, 0.5 cm, 1 cm, 2 cm, 3 cm, etc. In some embodiments, the first spatial position may be related to distribution positions relative to the user's ear and a microphone count in the second 160 microphone array. The first spatial position can be adjusted by adjusting the distribution positions relative to the user's ear and / or the microphone count in the second 160 microphone array. For example, the first spatial position can be made closer to the user's ear canal by increasing the microphone count in the second 160 microphone array.

[91] The signal processor 140 can estimate, based on the ambient noise acquired by the second microphone array 160 and the noise-reducing acoustic waveform, noise in the first spatial position. The ambient noise acquired by the second microphone array 160 can come from different azimuths and different types of spatial noise sources, so that the parameter information (e.g., phase information, amplitude information) corresponding to each spatial noise source may be different. In some embodiments, the signal processor 140 can perform signal separation and extraction in the noise in the first spatial position according to the statistical distribution and structural characteristics of different noise types in different dimensions (e.g., spatial domain, time domain, frequency domain, etc.), thus estimating different types (e.g., different frequencies, different phases, etc.).) of noise and estimating the parameter information (e.g., amplitude information, phase information, etc.) corresponding to each noise. In some embodiments, the signal processor 140 can also determine the overall parameter information of the noise at the first spatial position according to the parameter information corresponding to different types of noise at the first spatial position. In some embodiments, the estimation, based on the acquired ambient noise, of the noise at the first spatial position may further include determining one or more spatial noise sources associated with the acquired ambient noise and estimating the noise at the first spatial position based on the spatial noise sources. For example, the acquired ambient noise may be divided into a plurality of sub-bands. Each. Petition 870260059494, dated 06 / 18 / 2026, page 49 / 81 The 40 / 56 sub-band may correspond to a different frequency range, and in at least one sub-band, a spatial noise source corresponding to the sub-band can be determined. It should be noted that the spatial noise source estimated by the sub-band is a virtual noise source corresponding to a real external noise source here.

[92] The open acoustic device 100 may not block the user's ear canal and may not acquire ambient noise by placing a microphone in the ear canal. Therefore, the open acoustic device 100 can reconstruct the sound source in the ear canal through the second microphone array 160 to form the virtual sensor in the first spatial position. That is, a virtual sensor can be configured to represent or simulate audio data collected by a microphone located in the first spatial position. The audio data obtained by the virtual sensor may be similar or equivalent to the audio data collected by the physical sensor if a physical sensor is placed in the first spatial position. The first spatial position can be a spatial region constructed by the second microphone array 160 to simulate the position of the user's ear canal to more accurately estimate the ambient noise transmitted in the user's ear canal.In some embodiments, the first spatial position may be closer to the user's ear canal than any microphone in the second 160 microphone array. In some embodiments, the first spatial position may be related to the distribution positions and microphone count in the second 160 microphone array relative to the user's ear. The first spatial position can be adjusted by adjusting the distribution positions or the microphone count in the second 160 microphone array relative to the user's ear. For example, by increasing the microphone count in the second 160 microphone array, the first spatial position can be made closer to the user's ear canal. As another example, the first spatial position can be made closer to the user's ear canal by reducing the distance between the microphones in the second 160 microphone array.As another example, the first spatial position can be made closer to the user's ear canal by altering the arrangement of the microphones in the second microphone array 160. Petition 870260059494, dated 06 / 18 / 2026, pp. 50 / 81 41 / 56

[93] The signal processor 140 can estimate parameter information of the noise at the first spatial position based on parameter information (e.g., frequency information, amplitude information, phase information, etc.) of the ambient noise acquired by the second microphone array 160 and the noise-reducing acoustic waveform, thus estimating the noise at the first spatial position. For example, in some embodiments, there may be a spatial noise source in front of and behind the user's body. The signal processor 140 can estimate frequency information, phase information, or amplitude information of the spatial noise source in front of the user's body when the spatial noise source in front of the user's body is transmitted to the first spatial position according to the frequency information, phase information, or amplitude information of the spatial noise source in front of the user's body.The Signal Processor 140 can estimate frequency information, phase information, or amplitude information of the spatial noise source behind the user's body when the spatial noise source behind the user's body is transmitted to the first spatial position according to the frequency information, phase information, or amplitude information of the spatial noise source behind the user's body. The Signal Processor 140 can estimate, based on the frequency information, the phase information or amplitude information of the spatial noise source in front of the user's body and the frequency information, phase information, or amplitude information of the spatial noise source behind the user's body, noise information at the first spatial position, thus estimating the noise at the first spatial position.In some embodiments, audio signal parameter information can be extracted from a frequency response curve of the audio signal acquired by the second microphone array 160 through a feature extraction technique. In some embodiments, the technique for extracting audio signal parameter information may include, but is not limited to, a principal component analysis (PCA) technique, an independent component algorithm (ICA), a linear discriminant analysis (LDA) technique, a singular value decomposition (SVD) technique, etc.

[94] In some modes, one or more sources of spatial noise Petition 870260059494, dated 06 / 18 / 2026, pp. 51 / 81 42 / 56 related to acquired ambient noise can be determined by a noise positioning algorithm (e.g., a beamforming algorithm, a super-resolution spatial spectrum estimation algorithm, an arrival time difference algorithm, etc.). Specific descriptions of performing noise source positioning using the noise positioning algorithm can be found in the relevant descriptions in Figure 6, which will not be repeated here.

[95] In 820, the noise reduction signal can be updated based on the noise in the first spatial position.

[96] In some modes, the operation can be performed by the signal processor 140.

[97] In some embodiments, the signal processor 140 can adjust the parameter information (e.g., frequency information, amplitude information and / or phase information) of the noise reduction signal according to the parameter information of the noise (sound field) at the first spatial position obtained in operation 810, so that the updated amplitude and frequency information of the noise reduction signal can be more consistent with the amplitude and frequency information of the ambient noise in the user's ear canal and the updated phase information of the noise reduction signal can be more consistent with the inverse phase information of the ambient noise in the user's ear canal. Therefore, the updated noise reduction signal can more accurately eliminate ambient noise.The second microphone array 160 may need to monitor the sound field in the user's ear canal after the noise-canceling signal and ambient noise have been cancelled. The signal processor 140 can estimate the sound signal at the first spatial position (e.g., in the ear canal) based on the noise-canceling acoustic wave and ambient noise picked up by the second microphone array 160, to determine if the noise-canceling acoustic wave in the ear canal and the ambient noise are completely cancelled. The signal processor 140 can estimate the sound field in the ear canal through the sound signal acquired by the second microphone array 160 to update the noise-canceling signal. Petition 870260059494, dated 06 / 18 / 2026, pp. 52 / 81 43 / 56 noise, which can further improve the noise reduction effect and the user's listening experience.

[98] It should be noted that the above description of process 800 is provided merely for illustrative purposes and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of modifications and variations may be made to process 800 in accordance with the teachings of the present invention. However, such modifications and variations do not depart from the scope of the present invention.

[99] The loudspeaker of the open acoustic device may be located near the user's ear canal, and a transfer route of the noise-reducing acoustic wave output by the loudspeaker based on the noise-reducing signal may be transmitted from the loudspeaker to the user's ear canal (i.e., a general secondary route). Specifically, the specific route from the loudspeaker to the user's ear canal may be divided into a first secondary transfer route from the loudspeaker to the second microphone array and a second secondary transfer route from the second microphone array to the user's ear canal. After the noise-reducing acoustic wave generated by the loudspeaker based on the noise-reducing signal (the noise-reducing signal generated based on the noise signal in the ear canal) is transmitted to the opening of the user's ear canal, the parameter information (e.g., phase information, amplitude information, etc.)The acoustic waveform of the noise reduction device can be altered, so that the noise reduction acoustic waveform cannot completely cancel the noise at the user's ear canal opening. In order to improve the noise reduction effect of the open acoustic device, in some embodiments, the signal processor can determine a general secondary route transfer function between the loudspeaker and the user's ear canal based on the sound signal acquired by the second microphone array, and generate the noise reduction signal based on the general secondary route transfer function and the noise in the user's ear canal, so that the noise reduction acoustic waveform generated by the loudspeaker can completely cancel the noise at the ear canal opening when transmitted to the user's ear canal opening. Petition 870260059494, dated 06 / 18 / 2026, pp. 53 / 81 44 / 56 Specific descriptions regarding the generation of the noise reduction signal based on the noise signal in the user's ear canal can be found in Figures 9-12 and their respective descriptions.

[0100] Figure 9 is another flowchart illustrating an exemplary process for a second arrangement of microphones 160 participating in the work according to some embodiments of the present invention. As shown in Figure 9, the process 900 may include the following operations.

[0101] In 910, a general secondary transfer route function between the loudspeaker 150 and the user's ear canal can be determined based on a sound signal acquired by the second microphone array 160.

[0102] In some embodiments, the operation may be performed by the signal processor 140. In some embodiments, a transmission route of the sound signal from the loudspeaker 150 to the auditory canal may be referred to as the general secondary route. The general secondary route transfer function S(z) may refer to a phase frequency response of the sound signal (such as a noise-reducing acoustic wave emitted by the loudspeaker 150) from the loudspeaker 150 to the user's auditory canal, which may reflect the influence of the general secondary route on the sound signal. The signal processor 140 may estimate the noise-reducing signal based on the general secondary route transfer function S(z) and the sound signal in the user's auditory canal. Specific descriptions of the general secondary route transfer function S(z) may be found in Figure 11, a process 1100 and its relevant descriptions, which will not be repeated here.

[0103] In some noise reduction scenarios, if the influence of the overall secondary route on the sound signal is not considered, the noise reduction effect of the noise-reducing acoustic wave emitted by the speaker 150 may not be good, so that a noise reduction A acoustic wave signal output by the speaker 150 in the ear canal may not completely cancel an ambient noise signal in the ear canal. In order to improve this problem, the overall secondary route transfer function S(z) can be calculated to compensate for the noise-reducing acoustic wave emitted by the speaker 150, thus increasing the noise reduction effect of the noise-reducing acoustic wave emitted by the speaker. Petition 870260059494, dated 06 / 18 / 2026, pp. 54 / 81 45 / 56 150 in the user's ear canal.

[0104] In 920, the noise reduction signal can be estimated according to the noise signal in the user's ear canal and the overall secondary path transfer function S(z).

[0105] In some modes, the operation can be performed by signal processor 140.

[0106] In some embodiments, the signal processor 140 can compensate the noise reduction signal based on the overall secondary route S(z) calculated in operation 910, so that the noise reduction acoustic wave finally emitted by the loudspeaker can cancel the ambient noise in the ear canal after being adjusted by the overall secondary route transfer function. For example, the signal processor 140 can adjust parameter information (e.g., frequency information, amplitude information, phase information) of the noise reduction signal according to the ambient noise signal (e.g., sound pressure, sound frequency, sound amplitude, sound phase, vibration speed of the sound source or average density (e.g., air), etc.) in the ear canal.

[0107] In some modes, operation 920 may be included in operation 440.

[0108] It should be noted that the above description of process 900 is provided merely for illustrative purposes and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of modifications and variations may be made to process 900 in accordance with the teachings of the present invention. However, such modifications and variations do not depart from the scope of the present invention.

[0109] Figure 10 is a flowchart illustrating an exemplary process for estimating a noise reduction signal according to some embodiments of the present invention. That is, Figure 10 is an exemplary flowchart illustrating operation 920. As shown in Figure 10, process 1000 (operation 920) may include the following operations. Petition 870260059494, dated 06 / 18 / 2026, pp. 55 / 81 46 / 56

[0110] In 1010, the noise reduction acoustic waveform in the user's ear canal can be estimated based on the noise signal in the user's ear canal.

[0111] In some modes, the operation can be performed by signal processor 140.

[0112] In some embodiments, performing in a manner similar to operation 440, a noise reduction signal in the user's ear canal can be estimated, so that the noise reduction acoustic wave in the user's ear canal can be estimated.

[0113] In 1020, the noise reduction signal can be generated based on the noise reduction acoustic waveform in the user's ear canal and the overall secondary path transfer function S(z).

[0114] In some modes, the operation can be performed by signal processor 140.

[0115] In some embodiments, the signal processor 140 can adjust parameter information (e.g., frequency information, amplitude information, phase information) of the noise reduction signal according to the estimated noise reduction acoustic waveform (e.g., sound pressure, sound frequency, sound amplitude, sound phase, sound source vibration velocity, average density (e.g., air), etc.) in the user's ear canal.

[0116] It should be noted that the above description of process 1000 is provided merely for illustrative purposes and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of modifications and variations may be made to process 1000 under the teachings of the present invention. However, such modifications and variations do not depart from the scope of the present invention.

[0117] Figure 11 is a flowchart illustrating an exemplary process for determining a general secondary path transfer function S(z) according to some embodiments of the present invention. That is, Figure 11 is an exemplary flowchart illustrating operation 910. As shown in the figure Petition 870260059494, dated 06 / 18 / 2026, pp. 56 / 81 47 / 56 11, process 1100 (operation 910) may include the following operations.

[0118] In 1110, a first secondary route transfer function between loudspeaker 150 and second microphone array 160 can be determined based on the noise-reducing acoustic wave output by loudspeaker 150 and the sound signal acquired by second microphone array 160.

[0119] In some embodiments, the operation may be performed by the signal processor 140. Specifically, a transmission route of the sound signal (e.g., the noise-reducing acoustic wave output by the loudspeaker 150) from the loudspeaker 150 to the second microphone array 160 may be referred to as the first secondary route. The first secondary route transfer function S(z1) may refer to a frequency response of the sound signal (e.g., the noise-reducing acoustic wave output by the loudspeaker 150) from the loudspeaker 150 to the second microphone array 160, which may reflect the influence of the first secondary route on the sound signal. A face may reflect the acoustic wave, and the ways of use of different people may affect the transfer function of the first secondary route.In some embodiments, the loudspeaker 150 and the second microphone array 160 can convert the output noise-reducing audio signal and the acquired audio signal into electrical signals and transmit the electrical signals to the signal processor 140. The signal processor 140 can process the two electrical signals and calculate the first secondary route transfer function S(z1). For example, the first secondary route transfer function S(z1) can be expressed as a ratio of the audio signal acquired by the second microphone array 160 to the output noise-reducing audio signal by the loudspeaker 150.

[0120] In 1120, the overall secondary route transfer function can be determined based on the first secondary route transfer function.

[0121] In some embodiments, this step can be performed by signal processor 140. In some embodiments, signal processor 140 can be configured to determine the overall secondary route transfer function S(z) based on the first secondary route transfer function S(z1). In some embodiments, the determination, based on the first secondary route transfer function, Petition 870260059494, dated 06 / 18 / 2026, pp. 57 / 81 48 / 56 Secondary route transfer, the overall secondary route transfer function may include determining, based on the first secondary route transfer function, a second secondary route transfer function between the second microphone array and the user's ear canal; and determining, based on the first secondary route transfer function and the second secondary route transfer function, the overall secondary route transfer function. A transmission route of the sound signal from the second microphone array 160 to the user's ear canal may be referred to as the second secondary route. The second secondary route transfer function S(z2) may refer to a frequency response of the sound signal (e.g., the noise-reducing acoustic wave output by the loudspeaker 150) from the second microphone array 160 to the user's ear canal, which may reflect the influence of the second secondary route on the sound signal.The first secondary route transfer function S(z1) and the second secondary route transfer function S(z2) may have a certain relationship (for example, the second secondary route transfer function S(z2) = f(S(z1))). The second secondary route transfer function S(z2) can be determined through the first secondary route transfer function S(z1). In some embodiments, the second secondary route transfer function through a trained machine learning model or a predefined model can be determined based on the first secondary route transfer function. Specifically, the second secondary route transfer function S(z2) can be output by inserting the first secondary route transfer function S(z1) into the trained machine learning model or the predefined model.In some applications, the machine learning model may include a Gaussian mixture model, a deep neural network model, or a similar model, or any combination thereof.

[0122] In some embodiments, the predefined model can be obtained through manual test statistics. At this time, the second secondary route transfer function S(z2) may not be determined by the first secondary route transfer function S(z1). In some embodiments, in order to achieve the purpose of allowing the user's ears and ear canal to be unblocked, the second microphone array 160 may not be arranged in Petition 870260059494, dated 06 / 18 / 2026, pp. 58 / 81 49 / 56 user's ear canal, so the second secondary path transfer function S(z2) in the open acoustic device 100 may not be fixed. At this point, in a product debugging stage, one or more signal generation devices can be arranged in a position of the second microphone array 160 and one or more sensors can be arranged in the ear canal. One or more sensors arranged in the ear canal can receive the sound signal output from the signal generation device. Finally, the sound signal output from the signal generation device and the sound signal acquired by one or more sensors arranged in the ear canal can be converted into electrical signals, and the electrical signals can be transmitted to the signal processor 140, respectively. The signal processor 140 can analyze the two electrical signals and calculate the second secondary path transfer function S(z2).Furthermore, signal processor 140 can calculate a relationship S(z2)= f(S(z1)) between the second secondary route transfer function S(z2) and the first secondary route transfer function S(z1).

[0123] In some embodiments, the general secondary route transfer function S(z) can be calculated based on the first secondary route transfer function S(z1) and the second secondary route transfer function S(z2). For example, considering that the general secondary route transfer function, the first secondary route transfer function S(z1) and the second secondary route transfer function S(z2) can be affected by a surrounding environment (e.g., a face using the open acoustic device 100), the general secondary route transfer function and the first secondary route transfer function S(z1) and the second secondary route transfer function S(z2) can satisfy a certain functional relationship (e.g., S(z) = f(S(z1), S(z2)). The signal processor 140 can obtain the general secondary route transfer function in a real-world usage process by calling the function relationship.

[0124] It should be noted that the above description of process 1100 is provided merely for illustrative purposes and is not intended to limit the scope of the present invention. For those skilled in the art, a plurality of modifications and variations can be made to process 1100 in accordance with the Petition 870260059494, dated 06 / 18 / 2026, pp. 59 / 81 50 / 56 teachings of the present invention patent. However, these modifications and variations do not depart from the scope of the present invention patent.

[0125] Figure 12 is a flowchart illustrating an exemplary process for determining a first secondary route transfer function based on a noise-reducing acoustic wave output by loudspeaker 150 and a sound signal acquired by the second microphone arrangement 160 according to some embodiments of the present invention. That is, Figure 12 is an example flowchart illustrating operation 1110. As shown in Figure 12, process 1200 (operation 1110) may include the following operations.

[0126] In 1210, the noise-reducing acoustic waveform acquired by the second microphone array 160 can be obtained based on the sound signal acquired by the second microphone array 160.

[0127] In some embodiments, the operation can be performed by signal processor 140. In some embodiments, signal processor 140 can determine, based on the sound signal acquired by the second microphone array 160, the noise-reducing acoustic waveform acquired by the second microphone array 160. The method of performing operation 1210 is similar to the method of performing operation 1010, which will not be repeated here.

[0128] In 1220, the first secondary route transfer function S(z1) can be determined based on the noise-reducing acoustic wave output by loudspeaker 150 and the noise-reducing acoustic wave acquired by the second microphone array 160.

[0129] In some embodiments, the operation can be performed by signal processor 140. Signal processor 140 can calculate, based on the noise-reducing acoustic wave output by loudspeaker 150 and the noise-reducing acoustic wave acquired by the second microphone array 160, the first secondary route transfer function S(z1) from loudspeaker 150 to the second microphone array 160. Specifically, for example, loudspeaker 150 can reproduce a standard sound. The second microphone array 160 can acquire the standard sound signal output from loudspeaker 150. Signal processor 140 can compare relevant parameters (e.g., information from Petition 870260059494, dated 06 / 18 / 2026, pp. 60 / 81 51 / 56 frequency, amplitude, and phase information) of the sound signal output by loudspeaker 150 and related parameters (e.g., frequency, amplitude, and phase information) of the sound signal received by the second microphone array 160, thus calculating the first secondary route transfer function S(z1) from loudspeaker 150 to the second microphone array 160. In some embodiments, loudspeaker 150 may reproduce an alert sound or may reproduce a sound signal, such as a secondary acoustic wave that is not easily attracted the user's attention, in order to obtain the first secondary route transfer function S(z1).

[0130] It should be noted that the above description of process 1200 is provided merely for illustrative purposes and is not intended to limit the scope of the present invention. For those skilled in the art, under the guidance of this manual, various amendments and alterations may be made to process 1200. However, such modifications and variations do not fall outside the scope of the present invention.

[0131] Figures 13A-13D are schematic diagrams illustrating the distribution of a microphone array (e.g., the first microphone array) according to some embodiments of the present invention. In some embodiments, an arrangement of the microphone array may be a regular geometry. As shown in Figure 13A, the microphone array is a linear arrangement. In some embodiments, the arrangement of the microphone array may also have other shapes. For example, as shown in Figure 13B, the microphone array is a cross-shaped arrangement. As another example, as shown in Figure 13C, the microphone array may be a circular arrangement. In some embodiments, the microphone array may also be an irregular geometry. For example, as shown in Figure 13D, the microphone array is an irregular arrangement.It should be noted that the arrangement of the microphone array is not limited to the linear arrangement, the cross-shaped arrangement, the circular arrangement, the irregular arrangement shown in Figures 13A-13D, or the arrangement of the microphone array may also be an arrangement of other shapes, such as a triangular arrangement, a spiral arrangement, a planar arrangement, a three-dimensional arrangement, a radiation arrangement, etc., which is not limited herein. Petition 870260059494, dated 06 / 18 / 2026, pp. 61 / 81 52 / 56 invention patent.

[0132] In some embodiments, each short solid line in Figures 13A-13D may be considered as a microphone or a group of microphones. When each short continuous line is considered a group of microphones, the count of each group of microphones may be the same or different, the type of each group of microphones may be the same or different, and the orientation of each group of microphones may be the same or different. The type, count, and orientation of the microphone may be adjusted according to a real application, which will not be limited in the present invention patent.

[0133] In some embodiments, the microphones in the microphone array may be uniformly distributed. Uniform distribution here may refer to an equal distance between any two adjacent microphones in the microphone array. In some embodiments, the microphones in the microphone array may also be non-uniformly distributed. Non-uniform distribution here may refer to a different distance between any two adjacent microphones in the microphone array. The distance between the microphones in the microphone array may be adjusted according to a real situation, which will not be limited in this invention patent.

[0134] Figures 14A-14B are schematic diagrams illustrating arrangements of a microphone array (e.g., the first microphone array 130) according to some embodiments of the present invention. As shown in Figure 14A, when the user uses an acoustic device with a microphone array, the microphone array can be arranged in the user's ear or around it in a semicircular arrangement. As shown in Figure 14B, the microphone array can be arranged in the user's ear in a linear arrangement. It should be noted that the arrangement of the microphone array is not limited to the semicircular and linear arrangement shown in Figures 14A-14B. The position of the microphone array is not limited to the position shown in Figures 14A-14B. The semicircular and linear arrangement and the position of the microphone array are provided here for illustrative purposes only.

[0135] Having thus described the basic concepts, it may be quite evident to Petition 870260059494, dated 06 / 18 / 2026, pp. 62-81 53 / 56 those skilled in the art after reading this detailed invention patent that the previous detailed invention patent is intended to be presented only as an example and is not limiting. Various alterations, improvements and modifications may occur and are intended for those skilled in the art, although not expressly stated in this document. Such alterations, improvements and modifications are suggested by this invention patent and are within the spirit and scope of the exemplary embodiments of this invention patent.

[0136] Furthermore, certain terminology has been used to describe embodiments of the present invention. For example, the terms an embodiment, one of two or more embodiments, and / or some embodiments mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Therefore, it is emphasized and should be appreciated that two or more references to an embodiment or one of two or more embodiments or an alternative embodiment in various parts of this descriptive report do not necessarily refer to the same embodiment. Furthermore, particular features, structures, or characteristics may be combined as appropriate in one or more embodiments of this invention.

[0137] Furthermore, it will be appreciated by one skilled in the art that aspects of the present invention may be illustrated and described in this document in any of several patentable classes or contexts, including any new and useful process, machine, manufacture or composition of the object of the invention, or any new and useful improvement thereof. Consequently, aspects of the present invention may be implemented wholly in hardware, wholly in software (including firmware, resident software, microcode, etc.), module, motor, unit, component or system. In addition, aspects of the present invention may take the form of a computer program product embedded in one or more computer-readable media with computer-readable program code embedded therein.

[0138] A non-transient computer-readable signal medium may include a Petition 870260059494, dated 06 / 18 / 2026, pp. 63 / 81 54 / 56 A propagated data signal with computer-readable program code embedded therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take a variety of forms, including electromagnetic, optical or similar, or any suitable combination thereof. A computer-readable signal medium may be any computer-readable medium other than a computer-readable storage medium that can communicate, propagate or transport a program for use by or in connection with a system, apparatus or instruction-executing device. The program code embedded in a computer-readable signal medium may be transmitted using any appropriate medium, including wireless, wired, fiber optic cable, RF or similar, or any suitable combination thereof.

[0139] Furthermore, the indicated order of elements or processing sequences, or the use of numbers, letters, or other designations, is therefore not intended to limit the claimed processes and methods to any order except as specified in the claims. Although the above invention patent discusses through various examples what is currently considered a variety of useful embodiments of the invention patent, it should be understood that such detail is only for that purpose and that the appended claims are not limited to the disclosed embodiments but, on the contrary, are intended to cover equivalent modifications and arrangements that are within the spirit and scope of the disclosed embodiments. For example, although the implementation of several components described above may be incorporated into a hardware device, it may also be implemented as a software-only solution, for example, an installation on an existing server or mobile device.

[0140] Similarly, it should be appreciated that in the preceding description of the embodiments of the present invention, several features are sometimes grouped into a single embodiment, figure or description thereof for the purpose of simplifying the invention and aiding in the understanding of one or more of the various inventive embodiments. This method of invention patenting, however, should not be interpreted as reflecting an intention that the object Petition 870260059494, dated 06 / 18 / 2026, pp. 64 / 81 Claims 55 / 56 require more features than those expressly cited in each claim. Instead, the inventive embodiments are found in fewer than all the features of a single previously disclosed embodiment.

[0141] In some embodiments, the numbers expressing quantities, properties, and so forth, used to describe and claim certain embodiments of the application, shall be understood as being modified in some cases by the term "about," "approximately," or "substantially." For example, about, approximately, or substantially may indicate a variation of ± 20% of the value it describes, unless otherwise indicated. Consequently, in some embodiments, the numerical parameters set forth in the written description and appended claims are approximations that may vary depending on the desired properties to be obtained by a specific embodiment. In some embodiments, the numerical parameters must be interpreted in light of the reported number of significant digits and by applying common rounding techniques. Notwithstanding that the numerical ranges and parameters that establish the broad scope of some embodiments of the application are approximations, the numerical values ​​set forth in the specific examples are reported with the greatest possible accuracy.

[0142] Each of the patents, patent applications, patent application publications and other materials, such as articles, books, specifications, publications, documents, things and / or the like, referenced herein are incorporated herein by this reference in their entirety for all purposes, except for any tax claim documentation associated therewith, except for any such that is inconsistent with or conflicts with the present document, or any such that may have a limiting effect on the broader scope of the claims now or hereafter associated with the present document. By way of example, in the event of any inconsistency or conflict between the description, definition and / or use of a term associated with any incorporated material and that associated with the present document, the description, definition and / or use of the term in the present document shall prevail. Petition 870260059494, dated 06 / 18 / 2026, pp. 65 / 81 56 / 56

[0143] In conclusion, it should be understood that the application modalities disclosed here are illustrative of the principles of application modalities. Other modifications that may be employed may be within the scope of the application. Thus, by way of example, but not limitation, alternative configurations of application modalities may be used in accordance with the teachings contained herein. Therefore, the modalities of this application are not limited to those precisely as shown and described. Petition 870260059494, dated 06 / 18 / 2026, pp. 66 / 81

Claims

1 / 3 CLAIMS 1. An open acoustic device (100), characterized in that it comprises: a fixing structure (120) configured to fix the acoustic device (100) close to a user's ear without blocking the user's ear canal; a first microphone array (130) configured to acquire ambient noise; a signal processor (140) configured to: determine, based on the ambient noise, a primary route transfer function between the first microphone array (130) and the user's ear canal; estimate, based on the ambient noise and the primary route transfer function, a noise signal in the user's ear canal; generate, based on the noise signal in the user's ear canal, a noise reduction signal;a loudspeaker (150) configured to emit, according to the noise reduction signal, a noise reduction acoustic wave, the noise reduction acoustic wave being configured to eliminate the noise signal in the user's ear canal; and a second microphone array (160) configured to acquire ambient noise and the noise reduction acoustic wave; the signal processor (140) is further configured to estimate, based on the ambient noise acquired by the second microphone array (160) and the noise reduction acoustic wave, noise in a first spatial position, the first spatial position being closer to the user's ear canal than any microphone in the second microphone array (160); and Petition 870260059494, dated 06 / 18 / 2026, page 67 / 81 2 / 3 update, based on the noise in the first spatial position, the noise reduction signal.

2. Open acoustic device, according to claim 1, characterized in that the determination, based on ambient noise, of a primary route transfer function between the first microphone array (130) and the user's ear canal includes: a) estimating, based on ambient noise, the direction of a noise source; and b) determining the primary route transfer function according to the ambient noise, the direction of the noise source and the position information of the first microphone array (130) and the user's ear canal.

3. Open acoustic device, according to claim 2, characterized in that the position information of the first microphone array (130) and the user's ear canal includes a distance between the first microphone array (130) and the user's ear canal and the determination of the primary route transfer function according to the ambient noise, the direction of the noise source and the position information of the first microphone array and the user's ear canal includes determining the primary route transfer function based on an ambient noise frequency, the direction of the noise source and the distance between the first microphone array (130) and the user's ear canal.

4. Noise reduction method, characterized in that it comprises: a) determining, based on the ambient noise acquired by a first microphone array (130), a primary route transfer function between the first microphone array (130) and a user's ear canal; b) estimating, based on the ambient noise and the primary route transfer function, a noise signal in the user's ear canal; Petition 870260059494, dated 06 / 18 / 2026, p.68 / 81 3 / 3 c) generate, based on the noise signal in the user's ear canal, a noise reduction signal; d) emit, according to the noise reduction signal, a noise reduction acoustic wave, the noise reduction acoustic wave being configured to eliminate the noise signal in the user's ear canal; e) estimate, based on the ambient noise acquired by a second microphone array (160) and the noise reduction acoustic wave, noise at a first spatial position, the first spatial position being closer to the user's ear canal than any microphone in the second microphone array (160); ef) update, based on the noise at the first spatial position, the noise reduction signal. Petition 870260059494, dated 06 / 18 / 2026, pp. 69 / 81.

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