Signal processing method and acoustic system

Abstract

The application provides a signal processing method and an acoustic system. The method comprises the following steps: obtaining a first signal and a second signal, the first signal being obtained by a first sound sensor in a sound sensor module when collecting ambient sound, the second signal being obtained by a second sound sensor in the sound sensor module, and the ambient sound comprising at least target sound output by a loudspeaker module; performing a first target operation on the first signal and the second signal to generate a comprehensive signal; and performing a second target operation on the comprehensive signal, wherein the comprehensive signal is a combined signal of a signal in a first frequency band and a signal in a second frequency band, and the signal in the first frequency band is obtained from a sound collection result signal of the sound sensor module when the sound sensor module is directed to the loudspeaker module in a zero-point sound collection direction. The comprehensive signal generated by the above scheme reduces the signal component from the loudspeaker module, thereby suppressing howling or eliminating echo.

Description

Technical Field

[0001] This application relates to the field of acoustic technology, and in particular to a signal processing method and an acoustic system. Background Technology

[0002] Some acoustic systems include both loudspeakers and sound sensors. In these systems, the ambient sound captured by the sound sensor may include sound emitted from the loudspeaker, which is detrimental to the system's operation. For example, hearing aids use sound sensors to capture ambient sound, amplify it, and then play it through the loudspeaker to compensate for the wearer's hearing loss. When the sound emitted from the loudspeaker is re-captured by the sound sensor, the acoustic system forms a closed loop. Consequently, the sound emitted from the loudspeaker is continuously amplified within this loop, causing feedback and discomfort to the wearer. Similarly, in telephone or conferencing systems, voice signals from remote users are played through a local loudspeaker and captured by a local sound sensor along with the local user's voice before being transmitted back to the remote user. This can cause echo interference for the remote user. Summary of the Invention

[0003] This application provides a signal processing method and an acoustic system that can reduce the signal components from the loudspeaker module in the composite signal, thereby suppressing howling or eliminating echo.

[0004] In a first aspect, this application provides a signal processing method, comprising: obtaining a first signal, wherein the first signal is obtained by collecting ambient sound when a first sound sensor in a sound sensor module is working, the ambient sound including at least a target sound, the target sound being the sound output by a speaker module when it is working; obtaining a second signal, wherein the second signal is obtained by collecting the ambient sound when a second sound sensor in the sound sensor module is working; performing a first target operation on the first signal and the second signal to generate a composite signal, wherein the composite signal is a composite signal of a signal in a first frequency band and a signal in a second frequency band, the signal in the first frequency band originating from a pickup result signal of the sound sensor module in a target pickup state, the target pickup state corresponding to the zero-point pickup direction of the sound sensor module pointing towards the speaker module; and performing a second target operation on the composite signal.

[0005] In some embodiments, the signal in the second frequency band originates from the first signal.

[0006] In some embodiments, the first target operation includes: a zero-point differential operation, performing zero-point differential on the first signal and the second signal to adjust the zero-point pickup direction of the sound sensor module to point towards the speaker module, thereby obtaining the pickup result signal; and a signal synthesis operation, combining the component of the first frequency band in the pickup result signal with the component of the second frequency band in the first signal to obtain the composite signal.

[0007] In some embodiments, the zero-point differential operation includes: a first delay operation, delaying the second signal to obtain a second delayed signal; a first differential operation, differentially dividing the first signal and the second delayed signal to obtain a first differential signal; and a gain compensation operation, performing gain compensation on at least a portion of the frequency bands of the first differential signal to obtain the pickup result signal.

[0008] In some embodiments, the zero-point differential operation includes: a first delay operation, delaying the second signal to obtain a second delayed signal; a second delay operation, delaying the first signal to obtain a first delayed signal; a first differential operation, performing differential on the first signal and the second delayed signal to obtain a first differential signal; a second differential operation, performing differential on the second signal and the first delayed signal to obtain a second differential signal; a third differential operation, performing differential on the first differential signal and the second differential signal to obtain a third differential signal; and a gain compensation operation, performing gain compensation on at least a portion of the frequency bands of the third differential signal to obtain the pickup result signal.

[0009] In some embodiments, the zero-point differential operation further includes: a target parameter generation operation, which generates target parameters with the goal of minimizing the signal components in the third differential signal corresponding to the target sound; and a multiplication operation, performed between the second differential operation and the third differential operation, which multiplies the target parameters with the second differential signal to obtain a multiplication result, so that the third differential operation performs differential on the first differential signal and the multiplication result to obtain the third differential signal.

[0010] In some embodiments, the signal synthesis operation includes: performing a first filter on the first signal to obtain a component of the second frequency band in the first signal; performing a second filter on the pickup result signal to obtain a component of the first frequency band in the pickup result signal; and synthesizing the component of the first frequency band and the component of the second frequency band to obtain the synthesized signal.

[0011] In some embodiments, the first filter and the second filter are complementary filters.

[0012] In some embodiments, the first target operation includes: performing a first filter on the first signal to obtain a first sub-signal corresponding to the first frequency band in the first signal, and performing a second filter on the first signal to obtain a second sub-signal corresponding to the second frequency band in the first signal; performing the first filter on the second signal to obtain a third sub-signal corresponding to the first frequency band in the second signal; performing zero-point differential on the first sub-signal and the third sub-signal to obtain a target sub-signal; and combining the second sub-signal and the target sub-signal to obtain the composite signal.

[0013] In some embodiments, the phase of the signal component corresponding to the target sound in the second signal is earlier than or equal to the phase of the signal component corresponding to the target sound in the first signal.

[0014] In some embodiments, the frequency in the first frequency band is higher than the frequency in the second frequency band.

[0015] In some embodiments, the second frequency band includes the frequency band corresponding to the noise floor of the current environment, and the first frequency band includes frequency bands other than the second frequency band.

[0016] In some embodiments, the method further includes: determining the background noise characteristics corresponding to the current environment based on the first signal and the second signal; and determining the frequency range corresponding to the first frequency band and the frequency range corresponding to the second frequency band based on the background noise characteristics.

[0017] In some embodiments, the speaker module includes a first speaker and a second speaker, the first frequency band includes a first sub-frequency band and a second sub-frequency band, the sound emission frequency band of the first speaker includes the first sub-frequency band, and the sound emission frequency band of the second speaker includes the second sub-frequency band; the signal of the first sub-frequency band in the composite signal comes from a first sound pickup result signal obtained by the sound sensor module in a first sound pickup state, the first sound pickup state corresponding to the zero-point sound pickup direction of the sound sensor module pointing towards the first speaker; and the signal of the second sub-frequency band in the composite signal comes from a second sound pickup result signal obtained by the sound sensor module in a second sound pickup state, the second sound pickup state corresponding to the zero-point sound pickup direction of the sound sensor module pointing towards the second speaker, wherein the sound pickup direction patterns corresponding to the first sound pickup state and the second sound pickup state are different.

[0018] In some embodiments, the frequency in the first sub-band is lower than the frequency in the second sub-band; and the pickup direction pattern corresponding to the first pickup state is a heart shape, and the pickup direction pattern corresponding to the second pickup state is a figure-eight shape.

[0019] In some embodiments, the second target operation includes: gain amplifying the composite signal and sending the amplified signal to the speaker module to cause the speaker module to emit sound.

[0020] In some embodiments, the speaker module and the sound sensor module are deployed on a first acoustic device, the first acoustic device being communicatively connected to a second acoustic device; and the second target operation includes sending the composite signal to the second acoustic device to reduce the echo of the second acoustic device.

[0021] Secondly, this application also provides an acoustic system, comprising: a loudspeaker module that receives an input signal and outputs a target sound when in operation; a sound sensor module that includes at least: a first sound sensor and a second sound sensor, wherein the first sound sensor collects ambient sound and generates a first signal when in operation, and the second sound sensor collects the ambient sound and generates a second signal when in operation, wherein the ambient sound includes at least the target sound; and a signal processing circuit connected to the sound sensor module that executes the method described in any one of the first aspects when in operation.

[0022] In some embodiments, the signal processing circuit includes: at least one storage medium storing at least one instruction set for signal processing; and at least one processor communicatively connected to the sound sensor module and the at least one storage medium, wherein, when the acoustic system is running, the at least one processor reads the at least one instruction set and executes the method described in any one of the first aspects according to the instructions of the at least one instruction set.

[0023] In some embodiments, the acoustic system is any one of a hearing aid system, a loudspeaker system, a headphone system, a telephone system, or a conference system.

[0024] In some embodiments, the acoustic system is a hearing aid system, and the acoustic system further includes a housing, wherein the speaker module, the sound sensor module and the signal processing circuit are disposed within the housing, wherein when the acoustic system is worn on a user's head, the sound output end of the speaker module faces the user's head, and the pickup end of at least one sound sensor in the sound sensor module is located on the side of the housing away from the user's head.

[0025] As can be seen from the above technical solutions, this application provides a signal processing method and an acoustic system. The method includes: obtaining a first signal and a second signal, wherein the first signal is obtained by collecting ambient sound when a first sound sensor in a sound sensor module is working, and the second signal is obtained by collecting ambient sound when a second sound sensor in a sound sensor module is working, wherein the ambient sound includes at least a target sound output by a speaker module when it is working; performing a first target operation on the first signal and the second signal to generate a composite signal; and performing a second target operation on the composite signal, wherein the composite signal is a composite signal of a first frequency band signal and a second frequency band signal, wherein the first frequency band signal comes from the sound pickup result signal of the sound sensor module in a target sound pickup state, and the target sound pickup state corresponds to the zero-point sound pickup direction of the sound sensor module pointing towards the speaker module. In the above scheme, since the sound pickup result signal is obtained by the sound sensor module when the zero-point pickup direction is pointed towards the speaker module, the sound pickup result signal does not contain or contains less signal components from the speaker module. As a result, since the first frequency band in the composite signal comes from the sound pickup result signal, the signal components from the speaker module in the composite signal are reduced, thereby reducing the sound sensor module's pickup of the target sound emitted by the speaker module, so that the above acoustic system can achieve the effect of suppressing howling or eliminating echo.

[0026] Other functions of the acoustic system and signal processing method applied to the acoustic system provided in this application will be partially listed in the following description. The inventive aspects of the acoustic system and signal processing method applied to the acoustic system provided in this application can be fully explained by practice or by using the methods, apparatuses, and combinations described in the detailed examples below. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of a howling scenario provided according to an embodiment of this application is shown;

[0029] Figure 2 A schematic diagram of an echo scene provided according to an embodiment of this application is shown;

[0030] Figure 3A A schematic diagram of the structure of an acoustic system according to an embodiment of this application is shown;

[0031] Figure 3BA logical schematic diagram of an acoustic system provided according to an embodiment of this application is shown;

[0032] Figure 4 It shows Figures 3A-3B A schematic diagram of a design for the acoustic system shown.

[0033] Figure 5 A flowchart of a signal processing method provided according to an embodiment of this application is shown;

[0034] Figure 6 A schematic diagram of a signal processing procedure provided according to an embodiment of this application is shown;

[0035] Figure 7 A schematic diagram of a zero-point differential operation provided according to an embodiment of this application is shown;

[0036] Figure 8 It shows Figure 7 A schematic diagram of the pickup direction pattern corresponding to the zero-point differential operation;

[0037] Figure 9 It shows the use of Figure 7 The diagram shows the frequency response curve of the first differential signal obtained by the zero-point differential operation.

[0038] Figure 10 A schematic diagram of another zero-point differential operation provided according to an embodiment of this application is shown;

[0039] Figure 11 It shows Figure 10 The diagram shows the principle of pickup direction adjustment corresponding to zero-point differential operation.

[0040] Figure 12 It shows Figure 10 The diagram shows the pickup direction patterns of the zero-point differential operation in three different scenarios.

[0041] Figure 13 A schematic diagram of yet another zero-point differential operation provided according to an embodiment of this application is shown;

[0042] Figure 14 A schematic diagram illustrating the adjustment of the target parameter β to the zero-point pickup direction according to an embodiment of this application is shown;

[0043] Figure 15 A schematic diagram of another signal processing procedure provided according to an embodiment of this application is shown;

[0044] Figure 16 A schematic diagram of the frequency response curves corresponding to a set of complementary filtering operations provided according to an embodiment of this application is shown;

[0045] Figure 17 It shows Figure 15 A schematic diagram showing the noise floor components corresponding to the pickup result signal and the composite signal, respectively;

[0046] Figure 18 A schematic diagram illustrating the zero-point attenuation effect corresponding to different zero-point differential operations provided according to embodiments of this application is shown; and

[0047] Figure 19 A schematic diagram of yet another signal processing procedure provided according to an embodiment of this application is shown. Detailed Implementation

[0048] The following description provides specific application scenarios and requirements for this application, intended to enable those skilled in the art to make and use the content of this application. Various partial modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of this application. Therefore, this application is not limited to the embodiments shown, but rather to the widest scope consistent with the claims.

[0049] The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not restrictive. For example, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” used herein may also include the plural forms. When used in this application, the terms “comprising,” “including,” and / or “containing” mean that the associated integers, steps, operations, elements, and / or components are present, but do not exclude the presence of one or more other features, integers, steps, operations, elements, components, and / or groups, or that other features, integers, steps, operations, elements, components, and / or groups may be added to the system / method.

[0050] In view of the following description, these and other features of this application, as well as the operation and function of the related elements of the structure, and the economy of assembly and manufacture of the components, can be significantly improved. All of these form part of this application with reference to the accompanying drawings. However, it should be clearly understood that the drawings are for illustrative and descriptive purposes only and are not intended to limit the scope of this application. It should also be understood that the drawings are not drawn to scale.

[0051] The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be clearly understood that the operations in the flowcharts may not be implemented in a sequential order. Instead, the operations may be implemented in reverse order or simultaneously. Furthermore, one or more additional operations may be added to the flowcharts. One or more operations may be removed from the flowcharts.

[0052] For ease of description, the terms used in this application will be explained first.

[0053] Whistling: Whistling is a common phenomenon in acoustic systems. The following section combines... Figure 1 The process of howling is generated is explained. Figure 1 A schematic diagram of a feedback scenario 001 according to an embodiment of this application is shown, wherein the feedback scenario 001 can correspond to scenarios such as a loudspeaker system or a hearing aid / assisted hearing system. Figure 1 As shown, the feedback scenario 001 includes a speaker 110-A, a sound sensor 120-A, and a gain amplifier 130. The sound sensor 120-A collects ambient sound during operation. If the speaker 110-A is also playing sound synchronously during this process, the sound played by the speaker 110-A will also be collected by the sound sensor 120-A. Thus, the ambient sound collected by the sound sensor 120-A includes both sound from the target sound source 160 and sound from the speaker 110-A. This ambient sound is then input to the gain amplifier 130 for gain amplification and then played through the speaker 110-A. This forms a closed-loop circuit of "speaker-sound sensor-speaker" in the acoustic system. In this case, feedback occurs when sound signals of certain frequencies undergo self-excited oscillation. Such feedback can cause discomfort to the user, and in severe cases, it may damage the acoustic equipment. Furthermore, the presence of feedback limits the gain amplification factor of the gain amplifier 130, thereby restricting the maximum sound gain that the acoustic system 003 can achieve.

[0054] Echo: Echo is also a common phenomenon in acoustic systems. The following section will discuss this further. Figure 2 The process of echo generation is explained. Figure 2 A schematic diagram of an echo scene 002 according to an embodiment of this application is shown. Echo scene 002 can correspond to scenarios such as telephone systems, conferencing systems, and voice call systems. Figure 2As shown, echo scene 002 includes a local end and a remote end. The local end includes a local user 140-A, a speaker 110-A, and a sound sensor 120-A, while the remote end includes a remote user 140-B, a speaker 110-B, and a sound sensor 120-B. The local end and the remote end can be connected via a network. The network is a medium used to provide a communication connection between the local end and the remote end, facilitating the exchange of information or data between them. In some embodiments, the network can be any type of wired or wireless network, or a combination thereof. For example, the network can include a cable network, wired network, fiber optic network, telecommunications network, intranet, Internet, local area network (LAN), wide area network (WAN), wireless local area network (WLAN), metropolitan area network (MAN), public switched telephone network (PSTN), Bluetooth network, ZigBee network, near field communication (NFC) network, or similar networks. In some embodiments, the network can include one or more network access points. For example, the network may include wired or wireless network access points, such as base stations or internet exchange points, through which local and remote ends can connect to the network to exchange data or information.

[0055] See also Figure 2 During a call between local user 140-A and remote user 140-B, the remote voice emitted by remote user 140-B is collected by sound sensor 120-B and transmitted to the local end, where it is then played back by speaker 110-A. The remote voice played by speaker 110-A, along with the local voice emitted by local user 140-A, is collected by sound sensor 120-A at the local end and transmitted back to the remote end, where it is played back by speaker 110-B. In this way, remote user 140-B will hear their own echo, thus being interfered with by this echo. It should be noted that... Figure 2 The example illustrates the process by which remote user 140-B is affected by the echo interference. It should be understood that local user 140-A may also be affected by the echo interference. The echo generation process on the local end is similar to that described above and will not be repeated here. Such echoes can affect the user's normal call.

[0056] Background noise refers to ambient noise, generally referring to sounds from the surrounding environment other than the sound source being measured. In this application, any sound that is unwelcome, unwanted, or that interferes with the user's hearing can be called noise.

[0057] Sound pickup direction pattern: This refers to a pattern used to characterize the sensitivity of a sound sensor / sound sensor module to sound from different directions. Simply put, the sound pickup direction pattern can characterize the ability of a sound sensor / sound sensor module to pick up sound from different directions. Typically, sound pickup direction patterns can include: omnidirectional, cardioid, figure-eight, supercardioid, etc.

[0058] Zero-point pickup direction: Theoretically, if the sensitivity of a sound sensor / sound sensor module to sound in a certain direction is 0 or close to 0, then that direction is called the zero-point pickup direction. It should be understood that when a sound source is located in the zero-point pickup direction, the sound sensor / sound sensor module will theoretically not collect the sound emitted by that source. In practice, due to manufacturing errors of the sound sensor / sound sensor module and the fact that real-world sound sources are not necessarily ideal points, the sound sensor / sound sensor module can still collect a small amount of sound in the zero-point pickup direction. It should be noted that in this application, the zero-point pickup direction can refer to a specific direction or a range of directions encompassing multiple directions.

[0059] Far-field sound source: This refers to a sound source that is relatively far from the sound sensor / sound sensor module. Generally, when the distance between the sound source and the sound sensor / sound sensor module is greater than N times the physical size of the sound sensor / sound sensor module, the sound source can be approximated as a far-field sound source. It should be noted that the value of N can be different in different application scenarios. For example, in the case of headphones, the physical size of the sound sensor / sound sensor module can be less than or equal to 0.01m, and the value of N can be greater than or equal to 10. That is to say, a sound source that is greater than or equal to 0.1m from the sound sensor / sound sensor module can be considered a far-field sound source. Compared to near-field sound sources, the sound waves of far-field sound sources are approximately planar, and the amplitude of the sound waves decreases less as they propagate.

[0060] Near-field sound source: This refers to a sound source that is relatively close to the sound sensor / sound sensor module. Generally, when the distance between the sound source under test and the sound sensor / sound sensor module is less than 2 to 3 times the physical size of the sound sensor / sound sensor module, the sound source can be approximated as a far-field sound source. For example, in the case of headphones, a sound source with a distance of less than 0.1m can be considered a near-field sound source. Compared to the aforementioned far-field sound sources, the sound waves of near-field sound sources are closer to a sphere, and the amplitude of the sound waves decreases more significantly with propagation.

[0061] Before describing the specific embodiments of this application, the application scenarios of this application are first introduced as follows: The signal processing method and acoustic system provided by this application can be applied in scenarios requiring howling suppression (e.g., Figure 1 The scenario shown can also be applied to scenarios requiring echo cancellation (e.g., Figure 2 (Scenario shown). In the above scenario, the acoustic system collects ambient sound through a sound sensor module and processes the collected signal using the signal processing method described in this application to generate a composite signal, thereby reducing the signal component from the loudspeaker in the composite signal, and thus achieving the purpose of suppressing howling or echo cancellation.

[0062] It should be noted that the above-mentioned howling suppression and echo cancellation scenarios are only some of the multiple application scenarios provided in this application. The signal processing method and acoustic system provided in this application can also be applied to other similar scenarios. Those skilled in the art should understand that the application of the signal processing method and acoustic system provided in this application to other application scenarios is also within the scope of protection of this application.

[0063] Figure 3A A schematic diagram of the structure of an acoustic system 003 provided according to an embodiment of this application is shown; Figure 3B A logical schematic diagram of an acoustic system 003 according to an embodiment of this application is shown. The acoustic system 003 can be a public address system, a hearing aid / assisted hearing system, a telephone system, a conferencing system, or a voice communication system, etc. The acoustic system 003 may include: a speaker module 110, a sound sensor module 120, and a signal processing circuit 150. The sound sensor module 120 includes at least a first sound sensor 120-1 and a second sound sensor 120-2.

[0064] It should be noted that, Figures 3A-3B In the acoustic system 003 shown, the physical positional relationship between the speaker module 110, the first sound sensor 120-1, and the second sound sensor 120-2 can be arbitrary. Figures 3A-3B The physical positional relationship between the three components is not shown. For example, in some embodiments, the speaker module 110, the first sound sensor 120-1, and the second sound sensor 120-2 may be arranged in a straight line. In other embodiments, the speaker module 110 may be located (or substantially located) on the vertical line between the first sound sensor 120-1 and the second sound sensor 120-2, in which case the distance between the speaker module 110 and the first sound sensor 120-1 is equal (or substantially equal) to the distance between the speaker module 110 and the second sound sensor 120-2. Of course, other physical positional relationships are possible between the speaker module 110, the first sound sensor 120-1, and the second sound sensor 120-2, which will not be listed here.

[0065] In some embodiments, the acoustic system 003 is a hearing aid system. The acoustic system 003 may further include a housing 115, within which the speaker module 110, the sound sensor module 120, and the signal processing circuit 150 may be housed. The housing 115 protects the internal components and facilitates user handling and wearing. The acoustic system 003 can be worn on the user's head, for example, in-ear or over-ear. When the acoustic system 003 is worn on the user's head, the sound output end of the speaker module 110 faces the user's head, for example, towards or near the ear canal opening. The pickup end of at least one sound sensor in the sound sensor module 120 is located on the side of the housing 115 furthest from the user's head. This facilitates the pickup of ambient sound while minimizing the pickup of sound emitted by the speaker module 110.

[0066] The first sound sensor 120-1 and the second sound sensor 120-2 can be the same sound sensor or different sound sensors. For ease of description, in this application, the sound sensor closer to the speaker module 110 in the sound sensor module 120 is referred to as the second sound sensor 120-2, and the sound sensor farther from the speaker module 110 is referred to as the first sound sensor. That is, the second sound sensor 120-2 is closer to the speaker module 110 than the first sound sensor 120-1. In this way, the sound emitted by the speaker module 110 will be first collected by the second sound sensor 120-2 and then by the first sound sensor 120-1. In this case, the phase of the signal component corresponding to the target sound in the second signal is earlier than the phase of the signal component corresponding to the target sound in the first signal. When the distance between the two sound sensors and the speaker module 110 is equal, either one can be referred to as the first sound sensor 120-1 and the other as the second sound sensor 120-2. In this case, the phase of the signal component corresponding to the target sound in the second signal is equal to the phase of the signal component corresponding to the target sound in the first signal. In addition, the speaker module 110, the first sound sensor 120-1, and the second sound sensor 120-2 can be integrated on the same electronic device or can be independent of each other. This application does not limit this.

[0067] The speaker module 110 may include one speaker or multiple speakers. Unless otherwise specified, the following description will use a speaker module 110 with one speaker as an example. When the speaker module 110 includes multiple speakers, the multiple speakers may be arranged in an array, such as a linear array, planar array, spherical array, or other arrays. A speaker can also be called an electroacoustic converter, which is a device used to convert electrical signals into sound signals. For example, a speaker may be a horn.

[0068] When the speaker module 110 is in operation, it receives an input signal and converts it into audio for playback. The input signal refers to an electrical signal carrying sound information, and the audio refers to the sound played back by the speaker module 110. In some embodiments, the input signal received by the speaker module 110 may originate from the sound sensor module 120. This situation can correspond to... Figure 1 In the acoustic scenario shown, for example, after the sound sensor module 120 collects ambient sound and generates an electrical signal, it provides the electrical signal to the speaker module 110 for playback; or, the electrical signal is provided to the speaker module 110 for playback after undergoing preset processing. The preset processing may include at least one of amplification processing, noise reduction processing, and enhancement processing. In some embodiments, the input signal received by the speaker module 110 may also come from other electronic devices. This situation can correspond to... Figure 2 The acoustic scenario is illustrated. For example, the acoustic system 003 can receive an input signal from a remote device and convert the input signal into audio through the speaker module 110 for playback, or it can perform preset processing on the input signal and then convert it into audio for playback through the speaker module 110. The preset processing may include at least one of amplification processing, noise reduction processing, and enhancement processing.

[0069] A sound sensor (first sound sensor 120-1 and / or second sound sensor 120-2), also known as a sound-to-electrical converter or a sound pickup device, is a device used to collect sound and convert it into an electrical signal. For example, a sound sensor can be a microphone (MIC). When working, the sound sensor collects ambient sound and converts it into an electrical signal carrying sound information. The sound sensor can be an omnidirectional sound sensor, in which case it can collect ambient sound from all directions. Alternatively, it can be a directional sound sensor, in which case it can collect ambient sound from only some directions.

[0070] See also Figures 3A-3BIn some embodiments, the acoustic system 003 can sense and process sound from the target sound source 160. For example, the target sound source 160 can be an electronic device with sound playback function (e.g., a television, speaker, mobile phone, etc.), or, for example, the target sound source 160 can be a human throat. In this case, the ambient sound includes both sound from the target sound source 160 and sound from the speaker module 110. When the first sound sensor 120-1 operates, it collects the ambient sound and generates a first signal, which includes sound signals from the target sound source 160 and sound signals from the speaker module 110. When the second sound sensor 120-2 operates, it collects the ambient sound and generates a second signal, which includes sound signals from the target sound source 160 and sound signals from the speaker module 110. For ease of description, this application refers to the sound emitted by the speaker module 110 as the target sound, thus the ambient sound includes at least the target sound, the first signal includes at least a signal corresponding to the target sound, and the second signal includes at least a signal corresponding to the target sound.

[0071] The signal processing circuit 150 is connected to the sound sensor module 120, such as... Figures 3A-3BAs shown, the signal processing circuit 150 is connected to the first sound sensor 120-1 and the second sound sensor 120-2, respectively. Thus, the signal processing circuit 150 can obtain a first signal from the first sound sensor 120-1 and a second signal from the second sound sensor 120-2. Furthermore, the signal processing circuit 150 can perform a first target operation 40 on the first and second signals to generate a composite signal. The composite signal is a signal synthesized from a first frequency band signal and a second frequency band signal. The first frequency band signal originates from the sound sensor module 120's pickup result signal in a target pickup state, where the target pickup state corresponds to the sound sensor module 120's zero-point pickup direction pointing towards the speaker module 110. It is understood that since the pickup result signal is obtained by the sound sensor module 120 with its zero-point pickup direction pointing towards the speaker module 110, the pickup result signal contains little or no signal components from the speaker. Therefore, the first frequency band in the composite signal is taken from the pickup result signal, reducing the signal components from the speaker module 110 in the composite signal. In some embodiments, "reducing the signal component from speaker module 110 in the composite signal" can mean reducing the signal component from speaker module 110 in the composite signal relative to the first signal and / or the second signal. That is, the signal component from speaker module 110 in the composite signal is less than the signal component from speaker module 110 in the first signal, and / or less than the signal component from speaker module 110 in the second signal. In some embodiments, "reducing the signal component from speaker module 110 in the composite signal" can mean reducing the signal strength from speaker module 110 in the composite signal relative to the first signal and / or the second signal. That is, the signal strength from speaker module 110 in the composite signal is less than the signal strength from speaker module 110 in the first signal, and / or less than the signal strength from speaker module 110 in the second signal.

[0072] See also Figures 3A-3B After generating the composite signal, the signal processing circuit 150 can perform a second target operation 50 on the composite signal. In some embodiments, the second target operation 50 may include: amplifying the composite signal and sending the amplified signal to the speaker module 110, so that the speaker module 110 converts it into sound. The above scheme can be applied to, for example... Figure 1 The scenario shown illustrates feedback suppression. It should be understood that because the signal processing circuit 150 reduces the pickup of the target sound by the sound sensor module 120, the signal component from the speaker module 110 is reduced in the synthesized signal (or the signal strength from the speaker module 110 is reduced), thus disrupting the sound emitted by the speaker module 110. Figure 1The closed-loop circuit shown generates a whistling sound under certain conditions, thereby achieving the effect of suppressing the whistling sound.

[0073] In some embodiments, when the speaker module 110, the sound sensor module 120, and the signal processing circuit 150 are deployed in a first acoustic device, the first acoustic device can be communicatively connected to a second acoustic device. In this case, the second target operation 50 may include: sending the combined signal to the second acoustic device to reduce the echo of the second acoustic device. The above solution can be applied to, for example, Figure 2 The echo cancellation scenario is illustrated. For example, the first acoustic device can be a local device, and the second acoustic device can be a remote device. Since the composite signal sent by the first acoustic device to the second acoustic device reduces the signal component from the speaker module (or lowers the signal strength from the speaker module), it is equivalent to eliminating / reducing the sound from the second acoustic device. Therefore, when the second acoustic device receives the composite signal and plays it, the user on the second acoustic device side (i.e., the remote user) will not hear an echo, thus achieving the effect of echo cancellation.

[0074] The signal processing circuit 150 can be configured to execute the signal processing method described in this application. In some embodiments, the signal processing circuit 150 may include multiple hardware circuits connected together, each hardware circuit including one or more electrical components, which, when operating, implement one or more steps of the signal processing method described in this application. The multiple hardware circuits cooperate with each other to implement the signal processing method described in this application. In some embodiments, the signal processing circuit 150 may include a hardware device with data information processing capabilities and a necessary program for driving the hardware device to operate. The hardware device implements the signal processing method described in this application by executing the program. The signal processing method will be described in detail later.

[0075] Figure 4 A schematic diagram of a design for acoustic system 003 is shown. For example... Figure 4 As shown, the signal processing circuit 150 may include at least one storage medium 210 and at least one processor 220. The at least one processor 220 is communicatively connected to the speaker module 110, the first sound sensor 120-1, and the second sound sensor 120-2. It should be noted that, for illustrative purposes only, the signal processing circuit 150 in this application includes at least one storage medium 210 and at least one processor 220. Those skilled in the art will understand that the signal processing circuit 150 may also include other hardware circuit structures, which are not limited in this application, as long as they satisfy the functions mentioned in this application without departing from the spirit of this application.

[0076] See also Figure 4In some embodiments, the acoustic system 003 may further include a communication port 230. The communication port 230 is used for data communication between the acoustic system and external systems; for example, it can be used for data communication between the acoustic system and other devices / systems. In some embodiments, the acoustic system 003 may further include an internal communication bus 240. The internal communication bus 240 can connect different system components. For example, the speaker module 110, the first sound sensor 120-1, the second sound sensor 120-2, the processor 220, the storage medium 210, and the communication port 230 can all be connected via the internal communication bus 240.

[0077] Storage medium 210 may include a data storage device. The data storage device may be a non-transitory storage medium or a temporary storage medium. For example, the data storage device may include one or more of a disk 2101, a read-only storage medium (ROM) 2102, or a random access storage medium (RAM) 2103. Storage medium 210 also includes at least one instruction set stored in the data storage device. The instruction set includes instructions, which are computer program code. The computer program code may include programs, routines, objects, components, data structures, procedures, modules, etc., that execute the signal processing methods provided in this application.

[0078] At least one processor 220 is used to execute the at least one instruction set described above. When the acoustic system 003 is running, the at least one processor 220 reads the at least one instruction set and executes the signal processing method provided in this application according to the instructions of the at least one instruction set. The processor 220 can execute all or part of the steps included in the above signal processing method. The processor 220 can be in the form of one or more processors. In some embodiments, the processor 220 may include one or more hardware processors, such as a microcontroller, microprocessor, reduced instruction set computer (RISC), application-specific integrated circuit (ASIC), application-specific instruction set processor (ASIP), central processing unit (CPU), graphics processing unit (GPU), physical processing unit (PPU), microcontroller unit, digital signal processor (DSP), field-programmable gate array (FPGA), advanced RISC machine (ARM), programmable logic device (PLD), any circuit or processor capable of performing one or more functions, etc., or any combination thereof. This is merely for illustrative purposes. Figure 4The acoustic system 003 shown illustrates a case comprising only one processor 220. However, it should be noted that the acoustic system 003 provided in this application may also include multiple processors. Therefore, the operation and / or method steps disclosed in this application may be executed by one processor or by multiple processors in combination. For example, if the processor 220 of the acoustic system in this application executes steps A and B, it should be understood that steps A and B may also be executed jointly or separately by two different processors 220 (e.g., the first processor executes step A, the second processor executes step B, or the first and second processors jointly execute steps A and B).

[0079] Figure 5 A flowchart of a signal processing method according to an embodiment of this application is shown. The signal processing method P100 described in this application can be applied to the acoustic system 003 as previously described. Specifically, the signal processing circuit 150 can execute the signal processing method P100. Figure 5 As shown, the signal processing method P100 may include:

[0080] S310: Obtain a first signal, the first signal being ambient sound collected by the first sound sensor in the sound sensor module when it is working, the ambient sound including at least a target sound, the target sound being the sound output by the speaker module when it is working.

[0081] S320: Obtain a second signal, which is the ambient sound collected by the second sound sensor in the sound sensor module when it is working.

[0082] The signal processing circuit 150 can obtain a first signal from the first sound sensor 120-1 and a second signal from the second sound sensor 120-2. As mentioned above, since the ambient sound contains both the sound emitted by the target sound source 160 and the target sound emitted by the speaker module 110, the first signal and the second signal obtained by the signal processing circuit 150 both contain signal components from the target sound source 160 and signal components from the speaker module 110.

[0083] It should be noted that this application does not limit the execution order of S310 and S320. The execution order of the two can be interchanged, or the two can be executed simultaneously.

[0084] S330: Perform a first target operation on the first signal and the second signal to generate a composite signal, wherein the composite signal is a signal synthesized from the first frequency band signal and the second frequency band signal, the first frequency band signal comes from the sound sensor module's sound pickup result signal in the target sound pickup state, and the target sound pickup state corresponds to the zero-point sound pickup direction of the sound sensor module pointing towards the speaker module.

[0085] The signal processing circuit 150 can generate a composite signal by performing a first target operation 40 on the first signal and the second signal. The purpose of the first target operation 40 is to reduce the pickup of the target sound by the sound sensor module 120, thereby reducing the signal component from the speaker module 110 in the composite signal (i.e., reducing the signal component of the target sound in the composite signal). "Reducing the pickup of the target sound by the sound sensor module 120" means that the pickup of the target sound by the sound sensor module 120 is reduced when the first target operation is performed, compared to the pickup of the target sound by the sound sensor module 120 without performing the first target operation.

[0086] The composite signal is a frequency-band synthesized signal. Specifically, the composite signal can be a combined signal of a first frequency band and a second frequency band. The first frequency band signal originates from the sound pickup result signal of the sound sensor module 120 in a target pickup state, where the target pickup state corresponds to the zero-point pickup direction of the sound sensor module 120 pointing towards the speaker module 110. The second frequency band signal may not be derived from the pickup result signal but can be obtained through other means. In other words, a portion of the frequency bands in the composite signal originates from the pickup result signal, while another portion does not.

[0087] It should be noted that the phrase "zero-point pickup direction points to speaker module 110" should be understood as the zero-point pickup direction generally pointing towards speaker module 110. For example, the zero-point pickup direction could point to the center point of speaker module 110. Alternatively, the zero-point pickup direction could point to any point on the sound output surface of speaker module 110. Another example is that the zero-point pickup direction could point to a preset area on the sound output surface of speaker module 110. Furthermore, assuming the azimuth angle corresponding to the center point of speaker module 110 is θ, the azimuth angle corresponding to the zero-point pickup direction could be located at... Within the range.

[0088] The sound pickup result signal refers to a single-channel signal obtained by combining / superimposing the sound pickup signals of the first sound sensor 120-1 and the second sound sensor 120-2 when the sound sensor module 120 is pointing its zero-point pickup direction towards the speaker module 110. It should be understood that when the sound sensor module 120 is pointing its zero-point pickup direction towards the speaker module 110 (i.e., in the target pickup state), the sound emitted by the speaker module 110 is not collected by the sound sensor module 120, or is collected by a small amount. Therefore, the sound pickup result signal does not contain signal components from the speaker module 110, or contains very few signal components from the speaker module 110.

[0089] It is understood that since the sound pickup result signal does not contain or contains less signal components from the speaker module 110, when the first frequency band in the composite signal is taken from the sound pickup result signal, the composite signal also does not contain or contains less signal components from the speaker module 110. Therefore, the composite signal can reduce the signal components from the speaker module 110 compared to the first signal and the second signal.

[0090] In some embodiments, the signal in the second frequency band may originate from either the first or the second signal. Since both the first and second signals are raw signals acquired by the sound sensor, they more accurately reflect certain characteristics of real-world sound (e.g., background noise) compared to the pickup result signal. Therefore, when the signal in the second frequency band originates from either the first or the second signal, the composite signal retains components of the raw signal, thus more accurately reflecting the characteristics of real-world sound. It is understood that when the signal in the first frequency band originates from the pickup result signal and the signal in the second frequency band originates from either the first or the second signal, the composite signal retains components of the raw signal acquired by the sound sensor while reducing signal components from the speaker module 110. Therefore, the composite signal can reduce signal components from the speaker module 110 while accurately reflecting real-world sound as much as possible, thereby improving the accuracy of the composite signal.

[0091] For ease of description, the following description will use the example of the signal in the second frequency band originating from the first signal. It should be understood that when the signal in the second frequency band originates from the second signal, the implementation method is similar, and this application will not elaborate on this.

[0092] Figure 6 A schematic diagram of a signal processing procedure according to an embodiment of this application is shown. Figure 6As shown, in some embodiments, the first target operation 40 may include: a zero-point differential operation 41 and a signal synthesis operation 42. The zero-point differential operation 41 is configured to perform zero-point differential on the first signal and the second signal to adjust the zero-point pickup direction of the sound sensor module 120 to point towards the speaker module 110, thereby obtaining the pickup result signal. In this application, "zero-point differential" refers to a differential operation capable of adjusting the zero-point pickup direction of the sound sensor module 120. The signal synthesis operation 42 is configured to synthesize the first frequency band component of the pickup result signal with the second frequency band component of the first signal to obtain the composite signal. The signal processing circuit 150 performs the aforementioned zero-point differential operation 41 and signal synthesis operation 42 on the first signal and the second signal, such that the first frequency band component in the generated composite signal originates from the pickup result signal, and the second frequency band signal originates from the first signal.

[0093] In some embodiments, the zero-point differential operation 41 and / or signal synthesis operation 42 described above can be implemented by the processor 220 in the signal processing circuit 150, that is, the processor 220 executes an instruction set and performs the zero-point differential operation 41 and / or signal synthesis operation 42 according to the instructions of the instruction set. In some embodiments, the signal processing circuit 150 may include a zero-point differential circuit, through which the zero-point differential operation 41 can be implemented. In some embodiments, the signal processing circuit 150 may include a signal synthesis circuit, through which the signal synthesis operation 42 described above can be implemented.

[0094] The following is combined with Figures 7 to 14 Several implementation methods of the zero-point difference operation 41 are illustrated with examples.

[0095] Figure 7 A schematic diagram of a zero-point differential operation 41a according to an embodiment of this application is shown. Figure 7 As shown, the zero-point differential operation 41a may include a first delay operation 411 and a first differential operation 413. The first delay operation 411 is configured to delay the second signal to obtain a second delayed signal. The first differential operation 413 is configured to differentially divide the first signal and the second delayed signal (e.g., subtract the second delayed signal from the first signal) to obtain a first differential signal.

[0096] The above Figure 7The zero-point differential operation 41a shown can be applied to scenarios where the speaker module 110 is a far-field sound source. In this scenario, the distance between the speaker module 110 and the sound sensor module 120 is relatively large. It can be assumed that the amplitude and direction of the sound signals collected by the two sound sensors are the same, and there is only a time difference (i.e., a phase difference) between them. In this case, when the second sound sensor 120-2 is closer to the speaker module 110 than the first sound sensor 120-1, the sound emitted by the speaker module 110 is first collected by the second sound sensor 120-2 and then by the first sound sensor 120-1. That is, the phase of the signal component from the speaker module 110 in the second signal precedes the phase of the signal component from the speaker module 110 in the first signal. Therefore, by executing the first delay operation 411 (i.e., delaying the second signal to obtain a second delayed signal), the signal processing circuit 150 can align the phase of the signal component from the speaker module 110 in the second delayed signal with the phase of the signal component from the speaker module 110 in the first signal.

[0097] In some embodiments, when performing the first delay operation 411, the signal processing circuit 150 may determine the delay duration T corresponding to the second signal based on the following formula (1):

[0098] Formula (1) T = d / c

[0099] Where d is the distance between the first sound sensor 120-1 and the second sound sensor 120-2, and c is the speed of sound.

[0100] After performing the first delay operation 411, since the phase of the signal component from the speaker module 110 in the second delay signal is aligned with the phase of the signal component from the speaker module 110 in the first signal, the signal processing circuit 150 can cancel out the signal component from the speaker module 110 in the first signal and the signal component from the speaker module 110 in the second delay signal by performing the first differential operation 413 (i.e., subtracting the first signal from the second delay signal), thereby making the obtained first differential signal exhibit a zero-point pickup characteristic in the direction of the speaker module 110.

[0101] Figure 8 It shows Figure 7 The diagram shows the pickup direction pattern corresponding to the zero-point differential operation 41a. (See diagram for example.) Figure 8 As shown, the sound sensor module exhibits a zero-point pickup characteristic in the 180-degree direction. When the speaker module 110 is located in or near the 180-degree direction, the sound sensor module 120 will not collect (or collect very little) the sound emitted by the speaker module 110. Therefore, it can be seen that... Figure 7The zero-point differential operation 41a shown can adjust the pickup direction pattern of the sound sensor module 120 to a cardioid shape, with the zero-point pickup direction pointing towards the speaker module 110. Therefore, the signal processing circuit 150 performs the following operations on the first and second signals: Figure 7 The first differential signal obtained after the zero-point differential operation 41a shown does not contain (or contains less) signal components from the speaker module 110.

[0102] Furthermore, the inventors... Figure 7 Analysis and experiments using the zero-differential operation 41a revealed that it attenuates components in some frequency bands. The following section combines... Figure 9 Let's illustrate with examples. Figure 9 It shows the use of Figure 7 The diagram shows the frequency response curve of the first differential signal obtained from the zero-point differential operation 41a. Figure 9 As shown, curve 1 represents the frequency response curve of the first differential signal in the 0-degree direction, and curve 2 represents the frequency response curve of the first differential signal in the 90-degree direction. As can be seen from curves 1 and 2, the components of the first differential signal in some frequency bands (e.g., below 1000Hz) are attenuated, which means that the sound sensor module 120 has low sensitivity to sound signals in these frequency bands.

[0103] Therefore, in some embodiments, see also [reference needed]. Figure 7 The zero-point differential operation 41a may further include a gain compensation operation 416. The gain compensation operation 416 is configured to perform gain compensation on at least a portion of the frequency bands of the first differential signal to obtain the pickup result signal. For example, gain compensation can be performed on the components of the first differential signal that exhibit attenuation (e.g., below 1000Hz), so that the sound sensor module 120 also has high sensitivity to sound signals in these frequency bands. See also... Figure 9 Curve 3 shows the frequency response curve of the compensated first differential signal (i.e., the pickup result signal) in the 0-degree direction, and curve 4 shows the frequency response curve of the compensated first differential signal (i.e., the pickup result signal) in the 90-degree direction. It can be seen that the signal processing circuit 150, by performing the gain compensation operation 416 (i.e., performing gain compensation on at least a portion of the frequency bands of the first differential signal), enables the sound sensor module 120 to have high and relatively flat sensitivity to sound signals across the entire frequency range.

[0104] As mentioned above, Figure 7The zero-point differential operation 41a shown is applicable to scenarios where the speaker module 110 is a far-field sound source. During the inventors' research, it was discovered that when the distance between the speaker module 110 and the sound sensor module 120 is close (e.g., less than or equal to 0.1m), the aforementioned far-field assumption (i.e., the amplitude and direction of the sound signals acquired by the two sound sensors are the same, and there is only a time difference between them) no longer holds. Therefore, for near-field sound source scenarios, if... Figure 7 The zero-point differential operation 41a shown adjusts the pickup direction, so the adjusted pickup direction pattern no longer has a pickup zero point. Therefore, this application also provides another zero-point differential operation, which can be applied to both scenarios where the speaker module 110 is a far-field sound source and when the speaker module 110 is a near-field sound source. The following is in conjunction with... Figure 10 Please provide an explanation.

[0105] Figure 10 A schematic diagram of another zero-point differential operation 41b provided according to an embodiment of this application is shown. Figure 10 As shown, the zero-point differential operation 41b may include: a first delay operation 411, a second delay operation 412, a first differential operation 413, a second differential operation 414, and a third differential operation 415.

[0106] The first delay operation 411 is configured to delay the second signal to obtain a second delayed signal. In some embodiments, the delay duration of the second signal can be determined based on the aforementioned formula (1), which will not be elaborated here. The second delay operation 412 is configured to delay the first signal to obtain a first delayed signal. In some embodiments, the delay duration of the first signal can be determined based on the aforementioned formula (1), which will not be elaborated here. The first differential operation 413 is configured to perform a difference operation on the first signal and the second delayed signal (i.e., subtract the first signal from the second delayed signal) to obtain a first differential signal. The second differential operation 414 is configured to perform a difference operation on the second signal and the first delayed signal (i.e., subtract the second signal from the first delayed signal) to obtain a second differential signal. The third differential operation 415 is configured to perform a difference operation on the first differential signal and the second differential signal (i.e., subtract the first differential signal from the second differential signal) to obtain a third differential signal.

[0107] It should be understood that, Figure 10 The pickup direction adjustment principle of the zero-point differential operation 41b shown is similar to... Figure 7 They are similar, the difference lies in... Figure 10 The zero-point differential operation 41b requires two delay operations, therefore, Figure 7 The scheme shown can be called a single-delay zero-differential scheme. Figure 10The scheme shown can be called a double-delay zero-difference scheme. Figure 11 It shows Figure 10 The diagram shows the principle of pickup direction adjustment corresponding to the zero-point differential operation 41b. Figure 11 As shown, the signal processing circuit 150 can construct a heart-shaped pattern with the zero-point pickup direction pointing 180 degrees by executing the first delay operation 411 and the first differential operation 413 (see...). Figure 11 Pattern I in the diagram, the construction principle is the same as Figure 7 The same applies, so it will not be elaborated here. Furthermore, the signal processing circuit 150 can construct a heart-shaped pattern with the zero-point pickup direction pointing to 0 degrees by executing the second delay operation 412 and the second differential operation 414 (see...). Figure 11 Pattern II in the diagram, the construction principle is also similar to Figure 7 Similarly, details will not be elaborated here. It should be understood that... Figure 11 The heart-shaped pattern with the zero-point pickup direction pointing 180 degrees (i.e., pattern I) corresponds to the first differential signal, and the heart-shaped pattern with the zero-point pickup direction pointing 0 degrees (i.e., pattern II) corresponds to the second differential signal. The signal processing circuit 150 can obtain figure-eight patterns with zero-point pickup directions pointing 90 degrees and 270 degrees by performing the third differential operation 415 (equivalent to subtracting pattern I from pattern II). Figure 11 Pattern III in the text.

[0108] As can be seen from the figure-eight shaped sound pickup pattern (i.e., Pattern III), the sound sensor module 120 exhibits zero-point pickup characteristics in the 90-degree and 270-degree directions. When the speaker module 110 is located in or near the 90-degree / 270-degree direction, the sound sensor module 120 will not collect (or collects very little) the sound emitted by the speaker module 110. Therefore, it can be seen that... Figure 10 The zero-point differential operation 41b based on dual delay shown can adjust the pickup direction pattern of the sound sensor module 120 into a figure-eight shape, with the zero-point pickup direction pointing towards the speaker module 110. Therefore, the third differential signal obtained by the signal processing circuit 150 through executing the zero-point differential operation 41b does not contain (or contains very little) signal components from the speaker module 110.

[0109] Figure 12 It shows Figure 10 The diagram illustrates the pickup direction patterns of the zero-point differential operation 41b in three different scenarios. (See diagram for example.) Figure 12As shown, Pattern I illustrates the sound pickup direction pattern obtained when the distance between the speaker module 110 and the sound sensor module 120 is 1m; Pattern II illustrates the sound pickup direction pattern obtained when the distance between the speaker module 110 and the sound sensor module 120 is 0.1m; and Pattern III illustrates the sound pickup direction pattern obtained when the distance between the speaker module 110 and the sound sensor module 120 is 0.06m. Figure 12 It can be seen that regardless of the distance between the speaker module 110 and the sound sensor module 120, the following applies: Figure 10 The zero-point differential operation 41b shown can all produce a figure-eight pickup pattern. Therefore, Figure 10 The zero-point differential operation 41b shown can be applied to both scenarios where the speaker module 110 is a near-field sound source and scenarios where the speaker module 110 is a far-field sound source. Therefore, Figure 10 The zero-point differential operation 41b shown can effectively reduce the signal components from the speaker module 110 in the third differential signal in all scenarios.

[0110] For further details, please refer to [link / reference]. Figure 10 The zero-point differential operation 41b may also include a gain compensation operation 416. The gain compensation operation 416 is configured to perform gain compensation on at least a portion of the frequency bands of the third differential signal to obtain the pickup result signal. It should be understood that... Figure 10 Gain compensation operation 416 and Figure 7 The principle and function of the medium gain compensation operation 416 are the same, and will not be elaborated here.

[0111] In Adoption Figure 10In the case of the zero-point differential operation 41b shown, the pickup zero-point direction of the sound sensor module 120 points to 90 degrees and 270 degrees, that is, the positions on the vertical lines of the first sound sensor 120-1 and the second sound sensor 120-2 are located in the pickup zero-point direction of the sound sensor module 120. Therefore, in product design, the speaker module 110 can be placed on the vertical line of the first sound sensor 120-1 and the second sound sensor 120-2, so that the pickup signal of the sound sensor module 120 does not contain signal components from the speaker module 110. However, in practical applications, due to the influence of various factors such as product shape, manufacturing errors, and wearing posture, the speaker module 110 is usually not strictly located on the vertical line of the first sound sensor 120-1 and the second sound sensor 120-2. As a result, the signal component of the speaker module 110 in the pickup signal of the sound sensor module 120 is reduced compared to the pickup signal without the zero-point differential operation, but it still contains signal components from the speaker module 110. To this end, this application also provides another zero-point differential operation that can adaptively adjust the zero-point pickup direction, so that the signal component from the speaker module 110 in the pickup result signal is minimized. The following is in conjunction with... Figure 13 Please provide an explanation.

[0112] Figure 13 A schematic diagram of yet another zero-point differential operation 41c provided according to an embodiment of this application is shown. Figure 13 As shown, in Figure 10 Based on the zero-point differential operation 41b shown, the zero-point differential operation 41c may further include a multiplication operation 417 and a target parameter generation operation 418. The target parameter generation operation 418 generates a target parameter β with the goal of minimizing the signal component from the speaker module 110 in the third differential signal. The multiplication operation 417 is performed between the second differential operation 414 and the third differential operation 415, or between the first differential operation 413 and the third differential operation 415. For ease of description, the following description and accompanying drawings use the example of "multiplication operation 417 being performed between the second differential operation 414 and the third differential operation 415". Specifically, the multiplication operation 417 is configured to multiply the target parameter β with the second differential signal to obtain a multiplication result, so that the third differential operation 415 performs differential on the first differential signal and the multiplication result to obtain the third differential signal.

[0113] It should be understood that the second differential signal corresponds to Figure 11Pattern II (i.e., a heart-shaped pattern with the zero-point pickup direction pointing to 0 degrees) is used to adjust the second differential signal by multiplying the target parameter β with the second differential signal. Then, based on the first differential signal and the adjusted second differential signal, a third differential operation 415 is performed to adjust the zero-point pickup direction from 90 degrees / 270 degrees to other angles. Figure 14 A schematic diagram illustrating the adjustment of the target parameter β to the zero-point pickup direction according to an embodiment of this application is shown. Figure 14 As shown, when the target parameter β is 0.99, the zero points in the pickup direction pattern point to 90 degrees and 270 degrees. When the target parameter β is updated to 0.16, the zero points in the pickup direction pattern point to 135 degrees and 225 degrees. Therefore, the signal processing circuit 150 can adaptively adjust the zero-point pickup direction by performing the multiplication operation 417 and the target parameter generation operation 418, minimizing the signal component from the speaker module 110 in the pickup result signal.

[0114] It should be noted that the various zero-point differential operations 41 involved in this application (e.g.) Figure 7 The zero-point difference operation 41a shown Figure 10 The zero-point difference operation 41b shown is illustrated. Figure 13 The zero-point differential operation 41c shown can be performed in either the time domain or the frequency domain, and this application does not limit it.

[0115] In some embodiments, any one or more of the first delay operation 411, the second delay operation 412, the first differential operation 413, the second differential operation 414, the third differential operation 415, the gain compensation operation 416, the multiplication operation 417, and the target parameter generation operation 418 described above can be implemented by the processor 220 in the signal processing circuit 150, that is, the processor 220 executes an instruction set and performs one or more of the above operations according to the instructions of the instruction set. In some embodiments, the signal processing circuit 150 may include a first delay circuit, and the first delay operation 411 described above can be implemented by the first delay circuit. In some embodiments, the signal processing circuit 150 may include a second delay circuit, and the second delay operation 412 described above can be implemented by the second delay circuit. In some embodiments, the signal processing circuit 150 may include a first differential circuit, and the first differential operation 413 described above can be implemented by the first differential circuit. In some embodiments, the signal processing circuit 150 may include a second differential circuit, and the second differential operation 414 described above can be implemented by the second differential circuit. In some embodiments, the signal processing circuit 150 may include a third differential circuit, through which the third differential operation 415 described above can be implemented. In some embodiments, the signal processing circuit 150 may include a gain compensation circuit, through which the gain compensation operation 416 described above can be implemented. In some embodiments, the signal processing circuit 150 may include a multiplication circuit, through which the multiplication operation 417 described above can be implemented. In some embodiments, the signal processing circuit 150 may include a target parameter generation circuit, through which the target parameter generation operation 418 described above can be implemented.

[0116] As described above, zero-point difference operation 41 (e.g.) Figure 7 The zero-point difference operation 41a shown Figure 10 The zero-point difference operation 41b shown is illustrated. Figure 13 The zero-differential operation 41c) shown includes a gain compensation operation 416, which inevitably leads to an increase in the noise floor components in certain frequency bands of the pickup signal. When the noise floor is increased to a certain sound intensity, it will affect the user's auditory experience. Therefore, in some embodiments, the second frequency band may include the frequency band corresponding to the noise floor of the current environment, and the first frequency band includes frequency bands other than the second frequency band. In this way, when the component of the second frequency band (i.e., the frequency band corresponding to the noise floor) in the synthesized signal comes from the first signal, and the components of the first frequency band (other frequency bands besides the frequency band corresponding to the noise floor) come from the pickup signal, since the first signal has not undergone the zero-differential operation 41, it can truly reflect the noise floor characteristics of the current environment, thus avoiding the problem of the noise floor component being increased.

[0117] In some embodiments, the signal processing method P100 may further include: determining the noise floor characteristics of the current environment based on a first signal and a second signal, and then determining the frequency range corresponding to the first frequency band and the frequency range corresponding to the second frequency band based on the noise floor characteristics. For example, the noise floor characteristics may include the frequency band corresponding to the noise floor, or other characteristics that can indicate the frequency band corresponding to the noise floor. In this way, the signal processing circuit 150 can identify the frequency band corresponding to the noise floor based on the noise floor characteristics, and then determine the frequency band corresponding to the noise floor as the second frequency band, and determine the remaining frequency bands as the first frequency band. In the above scheme, the signal processing circuit 150 can adaptively adjust the frequency range of the first frequency band and the second frequency band based on the noise floor characteristics of the current environment, thereby reducing the signal components from the speaker module 110 in the integrated signal without increasing the noise floor in any scenario.

[0118] In practical applications, considering that the background noise in the environment is usually low-frequency noise, in some embodiments, the frequency in the first frequency band can be higher than the frequency in the second frequency band. For example, the first frequency band can be a high-frequency band, and the second frequency band can be a low-frequency band. Or, for example, the first frequency band can be a mid-high frequency band, and the second frequency band can be a low-frequency band. Or, for example, the first frequency band can be a high-frequency band, and the second frequency band can be a mid-low frequency band. Or, for example, the first frequency band can be a mid-frequency band, and the second frequency band can be a low-frequency band, and so on. That is, the frequency band corresponding to the lower frequency range of the audio pickup band of the sound sensor module 120 is used as the second frequency band, and the component of the second frequency band in the composite signal is taken from the first signal, thereby avoiding the problem of the background noise component being raised.

[0119] In this context, the low-frequency band refers to the frequency band roughly below 1kHz, the mid-frequency band refers to the frequency band roughly between 1kHz and 4kHz, the high-frequency band refers to the frequency band above 4kHz, the mid-low-frequency band refers to the frequency band roughly below 4kHz, and the mid-high-frequency band refers to the frequency band roughly above 1kHz. Those skilled in the art should understand that the above frequency band distinctions are merely examples to provide approximate ranges. The definitions of these frequency bands can vary depending on different industries, application scenarios, and classification standards. For example, in some application scenarios, the low-frequency band might refer to the frequency band roughly between 20Hz and 150Hz, the mid-frequency band might refer to the frequency band roughly between 150Hz and 5kHz, the high-frequency band might refer to the frequency band roughly between 5kHz and 20kHz, the mid-low-frequency band might refer to the frequency band roughly between 150Hz and 500Hz, and the mid-high-frequency band might refer to the frequency band between 500Hz and 5kHz. For example, in other application scenarios, the low frequency band refers to the frequency band from approximately 20Hz to 80Hz, the mid-low frequency band can refer to the frequency band from approximately 80Hz to 160Hz, the mid frequency band can refer to the frequency band from approximately 160Hz to 1280Hz, the mid-high frequency band can refer to the frequency band from approximately 1280Hz to 2560Hz, and the high frequency band can refer to the frequency band from approximately 2560Hz to 20kHz.

[0120] Figure 15 A schematic diagram of another signal processing procedure provided according to an embodiment of this application is shown, for use in processing... Figure 6 The signal synthesis operation 42 in the text will be explained in detail. It should be understood that... Figure 15 The zero-point difference operation 41 in the middle can be performed as follows: Figure 7 The zero-point difference operation 41a shown can also be performed as follows: Figure 10 The zero-point difference operation 41b shown can also be performed as follows: Figure 13 The zero-point differential operation 41c shown can be found in the relevant section above, and will not be repeated here.

[0121] like Figure 15As shown, signal synthesis operation 42 may include: a first filtering operation 421, a second filtering operation 422, and a synthesis operation 424. The first filtering operation 421 is configured to perform a first filtering on the first signal to obtain a second frequency band component in the first signal. For example, when the second frequency band is a low-frequency band, the first filtering operation 421 can be implemented using a low-pass filter. The second filtering operation 422 is configured to perform a second filtering on the pickup result signal to obtain a first frequency band component in the pickup result signal. For example, when the first frequency band is a high-frequency band, the second filtering operation 422 can be implemented using a high-pass filter. The synthesis operation 424 is configured to synthesize the second frequency band component obtained by the first filtering operation 421 and the first frequency band component obtained by the second filtering operation 422 to obtain the synthesized signal. In some embodiments, the synthesis operation 424 may be implemented using an adder.

[0122] As can be seen, the signal processing circuit 150 extracts the component of the second frequency band from the first signal by performing the first filtering operation 421, and extracts the component of the first frequency band from the sound pickup result signal by performing the second filtering operation 422. Then, it combines the components of the first frequency band and the components of the second frequency band by performing the synthesis operation 424 to obtain a composite signal, so that the first frequency band in the composite signal comes from the sound pickup result signal and the second frequency band comes from the first signal.

[0123] In some embodiments, the first filter and the second filter described above can be complementary filters, or in other words, the sum of the transfer functions of the first filter and the second filter is equal to 1. For example, assuming that the transfer function corresponding to the first filter is expressed as formula (2) below, the transfer function corresponding to the second filter can be expressed as formula (3) below.

[0124]

[0125]

[0126] As can be seen from formulas (2) and (3), the denominators of the transfer functions of the two filtering operations are the same, both being A(z), and the numerators are B(z) and A(z)-B(z), respectively. This design ensures that the sum of the transfer functions of the two filtering operations equals 1, thus giving the two filtering operations an all-pass characteristic when combined. For ease of understanding, Figure 16 A schematic diagram of the frequency response curves corresponding to a set of complementary filtering operations provided according to embodiments of this application is shown. For example... Figure 16 As shown, curve 1 can correspond to Figure 15 The frequency response curve of the first filter operation 421 in the middle exhibits low-pass characteristics, and curve 2 can correspond to... Figure 15The frequency response curve of the second filter operation 422 exhibits high-pass characteristics. When the two filter operations mentioned above are used in combination, they will exhibit full-pass characteristics.

[0127] It should be noted that the complementary filtering operations exemplified in formulas (2) and (3) above are merely possible examples. Those skilled in the art will understand that filter banks capable of frequency division and synthesis are feasible. For instance, in some embodiments, the first and second filters described above can also be implemented using a first filter and a second filter with the same cutoff frequency. Wherein, the cutoff frequency of the first filter is w1, and the cutoff frequency of the second filter is w2. The two filters have the same cutoff frequency: w1 = w2, and the amplitude responses of the two filters at the cutoff frequencies satisfy...

[0128] Figure 17 It shows Figure 15 A schematic diagram showing the noise floor components corresponding to the pickup result signal and the combined signal, respectively. (See diagram below.) Figure 17 As shown, curve 1 illustrates the noise floor component in the first signal acquired by the first sound sensor 120-1, and curve 2 illustrates the noise floor component in the second signal acquired by the second sound sensor 120-1. It can be understood that since the first and second signals are the raw signals acquired by the sound sensors, curves 1 and 2 can more accurately reflect the noise floor of the current environment. Curve 3 illustrates the noise floor component of the signal acquired by the second sound sensor 120-1. Figure 7 The noise floor component in the pickup signal obtained by the zero-point differential operation 41a (corresponding to the cardioid pickup direction pattern) is shown. Curve 4 illustrates the noise floor component in the pickup signal obtained by the zero-point differential operation 41a (corresponding to the cardioid pickup direction pattern). Figure 10 The noise floor component in the pickup signal obtained by the zero-differential scheme 41b (corresponding to the figure-eight pickup direction pattern) is shown. As can be seen from curves 3 and 4, regardless of... Figure 7 The zero-point differential operation 41a shown (single-delay zero-point differential scheme) is still... Figure 10 The zero-point differential operation 41b (double-delay zero-point differential scheme) shown will significantly increase the noise floor in the low-frequency band (i.e. the second frequency band), thereby causing significant noise interference to the user.

[0129] See also Figure 17 Curve 5 shows the effect of Figure 7 The image shows the pickup result signal obtained by the zero-point differential operation 41a (corresponding to the cardioid pickup direction pattern), and the noise floor component in the composite signal obtained by frequency band synthesis of the first signal. Curve 6 shows the noise floor component in the composite signal obtained by frequency band synthesis of the first signal. Figure 10The diagram shows the noise floor component in the pickup result signal obtained by the zero-point differential operation 41b (corresponding to the figure-eight pickup direction pattern) and the composite signal obtained by frequency band synthesis of the first signal. As can be seen from curves 5 and 6, the signal processing circuit 150 obtains the composite signal by frequency band synthesis of the pickup result signal and the first signal. This makes the noise floor component in the composite signal closer to the noise floor component in the original acquired first signal, avoiding the noise floor rise problem caused by the zero-point differential operation 41, thereby avoiding noise interference to the user.

[0130] In some embodiments, where the speaker module 110 includes multiple speakers, when different speakers correspond to different frequency bands, different zero-point differential schemes can be used for different frequency bands. This ensures that the zero-point pickup direction of the sound sensor module 120 in different frequency bands points to the corresponding speaker, thereby minimizing the signal components from each speaker in the composite signal. An example is given where the speaker module 110 includes a first speaker 110-1 and a second speaker 110-2. Assume the frequency band of the first speaker 110-1 includes the first sub-frequency band, and the frequency band of the second speaker 110-2 includes the second sub-frequency band. In this case, the signal of the first sub-frequency band in the composite signal originates from the first pickup result signal obtained by the sound sensor module 120 in the first pickup state, where the first pickup state corresponds to the zero-point pickup direction of the sound sensor module 120 pointing to the first speaker 110-1. The signal of the second sub-frequency band in the composite signal comes from the second pickup result signal obtained by the sound sensor module 120 in the second pickup state. The second pickup state corresponds to the zero-point pickup direction of the sound sensor module 120 pointing towards the second speaker 120-2. The pickup direction patterns corresponding to the first pickup state and the second pickup state are different. That is, when adjusting the zero-point pickup direction, the signal processing circuit 150 can use different zero-point differential operations 41 for the first and second sub-frequency bands respectively, so that the pickup direction pattern corresponding to the first sub-frequency band is different from that corresponding to the second sub-frequency band. In practical applications, considering that each zero-point differential scheme may have different zero-point attenuation effects (i.e., sound intensity attenuation in the zero-point pickup direction) in different frequency bands, the zero-point differential operation 41 with better zero-point attenuation effect can be used for the first and second sub-frequency bands respectively, thereby improving the overall zero-point attenuation effect of the frequency band.

[0131] Figure 18 A schematic diagram illustrating the zero-point attenuation effects corresponding to different zero-point differential operations provided according to embodiments of this application is shown. For example... Figure 18As shown, curve 1 illustrates the frequency response of the first signal acquired by the first sound sensor 120-1. Taking the first sound sensor 120-1 as an omnidirectional sound sensor as an example, curve 1 characterizes the frequency response of the first signal in any pickup direction. Curve 2 illustrates the frequency response of the first signal acquired by the first sound sensor 120-1. Figure 7 The diagram shows the frequency response of the pickup signal obtained by the zero-point differential operation 41a (corresponding to the cardioid pickup direction pattern) in the zero-point pickup direction. Curve 3 shows the frequency response of the pickup signal obtained by the zero-point pickup direction. Figure 10 The diagram shows the frequency response of the pickup signal obtained by the zero-point differential operation 41b (corresponding to the figure-eight pickup direction pattern) in the zero-point pickup direction. (From...) Figure 18 It can be seen that in the 1kHz-4kHz frequency band, the attenuation of curve 2 relative to curve 1 is greater than that of curve 3 relative to curve 1. In other words, Figure 7 The zero-point differential operation 41a shown (corresponding to the cardioid pickup pattern) has a sound intensity attenuation greater than 100° in the zero-point pickup direction. Figure 10 The zero-point differential operation 41b shown (corresponding to the figure-eight pickup pattern) exhibits sound intensity attenuation in the zero-point pickup direction. Therefore, in the 1kHz-4kHz frequency band, Figure 7 The zero-point attenuation effect of the zero-point differential operation 41a (corresponding to the cardioid pickup pattern) shown is better than that of the cardioid pickup pattern. Figure 10 The zero-point differential operation 41b shown corresponds to the figure-eight pickup direction pattern.

[0132] See also Figure 18 Within the 4kHz-8kHz frequency band, the attenuation of curve 3 relative to curve 1 is more significant than the attenuation of curve 2 relative to curve 1. In other words, Figure 10 The zero-point differential operation 41b shown (corresponding to the figure-eight pickup pattern) has a sound intensity attenuation greater than 100% in the zero-point pickup direction. Figure 7 The zero-point differential operation 41a (corresponding to a cardioid pickup pattern) shown exhibits sound intensity attenuation in the zero-point pickup direction. Therefore, in the 4kHz-8kHz frequency band, Figure 10 The zero-point attenuation effect of the zero-point differential operation 41b (corresponding to the figure-eight pickup pattern) shown is better than... Figure 7 The zero-point differential operation 41a shown (corresponding to the cardioid pickup direction pattern) is shown.

[0133] based on Figure 18 The comparison of zero-point attenuation effects shown can be illustrated in some embodiments where the first frequency band can be divided into a first sub-band and a second sub-band, with frequencies in the first sub-band lower than those in the second sub-band. For example, the first sub-band could be a mid-frequency band (e.g.,...). Figure 18 The second sub-band (shown as 1kHz-4kHz) can be a high-frequency band (e.g., 1kHz-4kHz). Figure 18(As shown in 4kHz-8kHz). In this case, the first sub-band can be treated as follows: Figure 7 The zero-point differential operation 41a shown here results in a heart-shaped pickup pattern corresponding to the sound sensor module 120; for the second sub-band, the following can be used: Figure 10 The zero-point differential operation 41b shown, or using, as shown in the figure, can be performed as follows: Figure 13 As shown in the zero-point differential operation 41c, the pickup direction pattern corresponding to the sound sensor module 120 is a figure-eight shape. Therefore, both the first and second sub-bands have significant attenuation in the zero-point pickup direction, thus improving the overall zero-point attenuation effect.

[0134] Figure 19 A schematic diagram of another signal processing procedure provided according to an embodiment of this application is shown, applicable to scenarios where the first sub-band and the second sub-band employ different zero-point differential operations. For example... Figure 19 As shown, assuming the speaker module 110 includes a first speaker 110-1 and a second speaker 110-2, the sound frequency band of the first speaker 110-1 includes a first sub-frequency band, and the sound frequency band of the second speaker 110-2 includes a second sub-frequency band. The zero-point differential operation 41 may include a first zero-point differential operation 41-1 and a second zero-point differential operation 41-2. The first zero-point differential operation 41-1 may employ, for example... Figure 7 The zero-point differential operation 41a shown (i.e., the single-delay zero-point differential scheme, corresponding to a cardioid pickup pattern) and the second zero-point differential operation 41-2 can be adopted as follows: Figure 10 The zero-point differential operation shown in 41b or Figure 13 The zero-point differential operation 41c shown is a dual-delay zero-point differential scheme, corresponding to a figure-eight pickup direction pattern. After obtaining the first signal and the second signal, the signal processing circuit 150 can perform a first zero-point differential operation 41-1 on the first signal and the second signal to make the zero-point pickup direction of the sound sensor module 120 point to the first speaker 110-1, thereby obtaining a first pickup result signal. Then, it can perform a second zero-point differential operation 41-2 on the first signal and the second signal to make the zero-point pickup direction of the sound sensor module 120 point to the second speaker 110-2, thereby obtaining a second pickup result signal. The first pickup result signal is a pickup result signal obtained based on a cardioid pickup direction pattern, and the second pickup result signal is a pickup result signal obtained based on a figure-eight pickup direction pattern.

[0135] See also Figure 19The signal synthesis operation 42 may include: a first filtering operation 421, a second filtering operation 422, a third filtering operation 423, and a synthesis operation 424. The first filtering operation 421 is configured to perform a first filtering on the first signal to obtain a second frequency band component in the first signal. For example, the second frequency band can be a low-frequency band (e.g., less than 1000Hz), in which case the first filtering operation 421 can be implemented using a low-pass filter. The second filtering operation 422 is configured to perform a second filtering on the first pickup result signal to obtain a first sub-frequency band component in the first pickup result signal. For example, the first sub-frequency band can be a high-frequency band (e.g., greater than 4kHz), in which case the second filtering operation 422 can be implemented using a high-pass filter. The third filtering operation 423 is configured to perform a third filtering on the second pickup result signal to obtain a second sub-frequency band component in the second pickup result signal. For example, the second sub-frequency band can be a mid-frequency band (e.g., 1kHz-4kHz), in which case the second filtering operation 422 can be implemented using a band-pass filter. The synthesis operation 424 is configured to synthesize the components of the second frequency band obtained from the first filtering operation 421, the components of the first sub-frequency band obtained from the second filtering operation 422, and the components of the second sub-frequency band obtained from the third filtering operation 423 to obtain a synthesized signal. In some embodiments, the synthesis operation 424 may be implemented using an adder. (Continue to see...) Figure 19 After obtaining the synthesized signal, the signal processing circuit 150 performs a gain amplification operation 51 on the synthesized signal to obtain a gain-amplified signal. Then, based on the sound frequency bands of the first speaker 110-1 and the second speaker 110-2, it performs a frequency division operation 52 on the gain-amplified signal and sends the frequency-divided signals to the first speaker 110-1 and the second speaker 110-2 respectively. For example, assuming the sound frequency band of the first speaker 110-1 includes a second frequency band and a first sub-frequency band, and the sound frequency band of the second speaker 110-2 includes a second sub-frequency band, in this case, the frequency division operation 52 can extract a first target signal corresponding to the second frequency band and the first sub-frequency band from the gain-amplified signal, and extract a second target signal corresponding to the second sub-frequency band. Then, the signal processing circuit 150 can send the first target signal to the first speaker 110-1 and the second target signal to the second speaker 110-2. The frequency division operation 52 can be implemented using a filter, or other feasible methods, which are not limited in this application.

[0136] It should be noted that in the scenario where the speaker module 110 includes a first speaker 110-1 and a second speaker 110-2, Figure 19The signal processing procedure shown is only one possible example. In practical applications, after obtaining the first and second pickup result signals, the signal processing circuit 150 can also employ other signal processing methods. For example, in some embodiments, the signal processing circuit 150 can perform a first filtering operation 421 on the first signal to obtain the component of the second frequency band in the first signal, perform a second filtering operation 422 on the first pickup result signal to obtain the component of the first sub-frequency band in the first pickup result signal, and perform a third filtering operation 423 on the second pickup result signal to obtain the component of the second sub-frequency band in the second pickup result signal. Furthermore, the signal processing circuit synthesizes the component of the first sub-frequency band and the component of the second frequency band to obtain a first composite signal, performs a first gain amplification operation on the first composite signal and sends it to the first speaker 110-1, and performs a second gain amplification operation on the component of the second sub-frequency band and sends it to the second speaker 110-2.

[0137] and Figure 15 Similar to the example shown, Figure 19 The first filtering operation 421, the second filtering operation 422, and the third filtering operation 423 can be referred to as a set of complementary filters. In other words, the sum of the transfer functions of the first filtering operation 421, the second filtering operation 422, and the third filtering operation 423 equals 1. For an explanation of the complementary filters and their effects, please refer to the relevant descriptions above; they will not be repeated here.

[0138] In some embodiments, any one or more of the first filtering operation 421, the second filtering operation 422, the third filtering operation 423, and the synthesis operation 424 described above can be implemented by the processor 220 in the signal processing circuit 150, that is, the processor 220 executes an instruction set and performs one or more of the above operations according to the instructions of the instruction set. In some embodiments, the signal processing circuit 150 may include a first filtering circuit, and the first filtering operation 421 described above can be implemented by the first filtering circuit. In some embodiments, the signal processing circuit 150 may include a second filtering circuit, and the second filtering operation 422 described above can be implemented by the second filtering circuit. In some embodiments, the signal processing circuit 150 may include a third filtering circuit, and the third filtering operation 423 described above can be implemented by the third filtering circuit. In some embodiments, the signal processing circuit 150 may include a synthesis circuit, and the synthesis operation 424 described above can be implemented by the synthesis circuit.

[0139] In the foregoing embodiments, when generating the composite signal, the signal processing circuit 150 first performs a zero-point differential operation 41 to differentiate the first signal and the second signal to obtain a pickup result signal. Then, it filters the pickup result signal and the first signal to extract the first frequency band component from the pickup result signal and the second frequency band component from the first signal. Finally, it synthesizes the components of the two frequency bands to obtain the composite signal. In some embodiments, the signal processing circuit 150 can also interchange the order of the zero-point differential operation 41 and the filtering. Specifically, with... Figure 15 Taking the two-band synthesis scheme shown as an example, the signal processing circuit 150 can generate the synthesized signal in the following manner: The first signal is subjected to a first filter to obtain a first sub-signal corresponding to the first frequency band; the first signal is subjected to a second filter to obtain a second sub-signal corresponding to the second frequency band; the second signal is subjected to the first filter to obtain a third sub-signal corresponding to the first frequency band; then, zero-point differential is performed on the first sub-signal and the third sub-signal to obtain a target sub-signal; finally, the second sub-signal and the target sub-signal are synthesized to obtain the synthesized signal. It should be understood that the specific implementation methods of the above zero-point differential operation, filtering operation, and synthesis operation are the same as or similar to those described above, and will not be repeated here.

[0140] S340: Perform a second target operation on the synthesized signal.

[0141] After obtaining the synthesized signal, the signal processing circuit 150 can perform a second target operation 50 on the synthesized signal based on the requirements of the application scenario. In some embodiments, see also... Figure 15 and Figure 19 The signal processing circuit 150 can also be connected to the speaker module 110. In this case, the second target operation 50 may include a gain amplification operation 51. After obtaining the synthesized signal, the signal processing circuit 150 can amplify the synthesized signal by performing the gain amplification operation 51, and then send the amplified signal to the speaker module 110 to make the speaker module 110 emit sound. The above solution can be applied to, for example... Figure 1 The scenario shown illustrates feedback suppression. It should be understood that by reducing the signal component from speaker module 110 in the synthesized signal (or lowering the signal strength from speaker module 110), the sound emitted by speaker module 110 is disrupted. Figure 1The conditions for the closed-loop circuit to generate howling are shown, thereby achieving the effect of suppressing howling. In some embodiments, the above-described gain amplification operation 51 can be implemented by the processor 220 in the signal processing circuit 150, that is, the processor 220 executes the instruction set and performs the above-described gain amplification operation 51 according to the instructions of the instruction set. In some embodiments, the signal processing circuit 150 may include a gain amplification circuit, and the above-described gain amplification operation 51 can be implemented by the gain amplification circuit.

[0142] In some embodiments, the speaker module 110, the sound sensor module 120, and the signal processing circuit 150 are integrated in a first acoustic device, which is communicatively connected to a second acoustic device. In this case, the second target operation 50 may include sending the combined signal to the second acoustic device to reduce the echo of the second acoustic device. The above solution can be applied to, for example, Figure 2 The echo cancellation scenario is illustrated. For example, the first acoustic device can be a local device, and the second acoustic device can be a remote device. Since the signal component from the loudspeaker is reduced in the composite signal (or the signal strength from the loudspeaker is lowered), it is equivalent to reducing the sound from the second acoustic device. Therefore, when the second acoustic device receives the composite signal and plays it, the user on the second acoustic device side (i.e., the remote user) will not hear or will hear very little echo, thus achieving the effect of echo cancellation.

[0143] In summary, this application provides a signal processing method and an acoustic system. The method includes: obtaining a first signal and a second signal, wherein the first signal is obtained by collecting ambient sound from a first sound sensor in a sound sensor module when it is working, and the second signal is obtained by collecting ambient sound from a second sound sensor in the sound sensor module when it is working. The ambient sound includes at least a target sound output by a loudspeaker when it is working. The method involves performing a first target operation on the first signal and the second signal to generate a composite signal, and performing a second target operation on the composite signal. The composite signal is a composite signal of a first frequency band signal and a second frequency band signal. The first frequency band signal originates from the sound pickup result signal of the sound sensor module in a target pickup state, where the target pickup state corresponds to the zero-point pickup direction of the sound sensor module pointing towards the loudspeaker. In this solution, since the pickup result signal is obtained by the sound sensor module when the zero-point pickup direction is pointing towards the loudspeaker, the pickup result signal contains little or no signal components from the loudspeaker. Furthermore, since the first frequency band in the composite signal originates from the pickup result signal, the signal components from the loudspeaker in the composite signal are reduced. Therefore, the acoustic system can achieve the effect of suppressing howling or eliminating echoes.

[0144] This application, in another aspect, provides a non-transitory storage medium storing at least one set of executable instructions for performing signal processing. When the executable instructions are executed by a processor, they instruct the processor to implement the steps of the signal processing method P100 described in this application. In some possible embodiments, various aspects of this application can also be implemented as a program product comprising program code. When the program product is run on an acoustic system 003, the program code is used to cause the acoustic system 003 to perform the steps of the signal processing method P100 described in this application. The program product for implementing the above method can employ a portable compact disc read-only memory (CD-ROM) containing program code and can run on the acoustic system 003. However, the program product of this application is not limited thereto. In this application, the readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system. The program product can employ any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. The computer-readable storage medium may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable storage medium may also be any readable medium other than a readable storage medium that can send, propagate, or transmit programs for use by or in connection with an instruction execution system, apparatus, or device. Program code contained on a readable storage medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination thereof. Program code for performing the operations of this application can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, and conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the acoustic system 003, partially on the acoustic system 003, as a standalone software package, partially on the acoustic system 003 and partially on a remote computing device, or entirely on a remote computing device.

[0145] The foregoing has described specific embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0146] In summary, after reading this detailed disclosure, those skilled in the art will understand that the foregoing detailed disclosure is presented by way of example only and is not restrictive. Although not explicitly stated herein, those skilled in the art will understand that the requirements of this application encompass various reasonable changes, improvements, and modifications to the embodiments. These changes, improvements, and modifications are intended to be made by this application and are within the spirit and scope of the exemplary embodiments of this application.

[0147] Furthermore, certain terms used in this application have been used to describe embodiments of this application. For example, "an embodiment," "an embodiment," and / or "some embodiments" mean that a particular feature, structure, or characteristic described in connection with that embodiment may be included in at least one embodiment of this application. Therefore, it is to be emphasized and understood that two or more references to "an embodiment" or "an embodiment" or "alternative embodiment" in various parts of this application do not necessarily refer to the same embodiment. Moreover, specific features, structures, or characteristics may be appropriately combined in one or more embodiments of this application.

[0148] It should be understood that in the foregoing description of the embodiments of this application, various features are combined in a single embodiment, drawing, or description for the purpose of simplifying the understanding of a feature. However, this does not mean that the combination of these features is necessary, and those skilled in the art may readily identify some of the devices as separate embodiments when reading this application. That is, the embodiments in this application can also be understood as an integration of multiple sub-embodiments. It is also valid when each sub-embodiment contains fewer than all the features of a single foregoing disclosed embodiment.

[0149] Every patent, patent application, publication of a patent application, and other material such as articles, books, specifications, publications, documents, articles, etc., cited herein, except for any related historical prosecution documents, any identical ones that may be inconsistent with or conflict with this document, or any identical historical prosecution documents that may have a limiting effect on the widest scope of the claims, may be incorporated herein by reference and used for all purposes now or hereafter in connection with this document. Furthermore, in the event of any inconsistency or conflict between the description, definition, and / or use of terms related to any included material and those related to this document, the terminology used herein shall prevail.

[0150] Finally, it should be understood that the embodiments disclosed herein are illustrative of the principles of the embodiments of this application. Other modified embodiments are also within the scope of this application. Therefore, the embodiments disclosed herein are merely examples and not limitations. Those skilled in the art can adopt alternative configurations to implement the applications in this application based on the embodiments in this application. Therefore, the embodiments of this application are not limited to the embodiments precisely described in the application.

Claims

1. A signal processing method, characterized in that, Applied to acoustic systems, including: A first signal is obtained, wherein the first signal is the ambient sound collected by the first sound sensor in the sound sensor module when it is working, and the ambient sound includes at least the target sound, wherein the target sound is the sound output by the speaker module when it is working; A second signal is obtained, which is the ambient sound collected by the second sound sensor in the sound sensor module when it is working; the second sound sensor and the first sound sensor are installed in different positions on the acoustic system. A first target operation is performed on the first signal and the second signal to generate a composite signal; wherein the composite signal is a signal synthesized from a signal in a first frequency band and a signal in a second frequency band; the signal in the first frequency band comes from the sound sensor module's sound pickup result signal in the target sound pickup state; the signal in the second frequency band includes the signal portion of the first signal or the second signal located in the frequency band corresponding to the background noise of the current environment; the first frequency band includes frequency bands other than the second frequency band, and the target sound pickup state corresponds to the zero-point sound pickup direction of the sound sensor module pointing towards the speaker module; and Perform a second target operation on the synthesized signal.

2. The method according to claim 1, characterized in that, The first target operation includes: Zero-point differential operation is performed on the first signal and the second signal to adjust the zero-point pickup direction of the sound sensor module to point towards the speaker module, thereby obtaining the pickup result signal; and The signal synthesis operation combines the first frequency band component of the pickup result signal with the second frequency band component of the first signal to obtain the composite signal.

3. The method according to claim 2, characterized in that, The zero-point difference operation includes: The first delay operation involves delaying the second signal to obtain the second delayed signal; The first differential operation involves performing a differential operation on the first signal and the second delayed signal to obtain a first differential signal; and The gain compensation operation is performed on at least a portion of the frequency bands of the first differential signal to obtain the pickup result signal.

4. The method according to claim 2, characterized in that, The zero-point difference operation includes: The first delay operation involves delaying the second signal to obtain the second delayed signal; The second delay operation involves delaying the first signal to obtain the first delayed signal; The first differential operation involves performing a differential operation on the first signal and the second delayed signal to obtain a first differential signal; The second differential operation involves performing a differential operation between the second signal and the first delayed signal to obtain a second differential signal; The third differential operation involves performing a differential operation on the first differential signal and the second differential signal to obtain a third differential signal; and The gain compensation operation is performed on at least a portion of the frequency bands of the third differential signal to obtain the pickup result signal.

5. The method according to claim 4, characterized in that, The zero-point difference operation also includes: The target parameter generation operation generates target parameters with the objective of minimizing the signal components in the third differential signal corresponding to the target sound; and The multiplication operation is performed between the second difference operation and the third difference operation, multiplying the target parameter with the second difference signal to obtain the multiplication result, so that the third difference operation performs difference on the first difference signal and the multiplication result to obtain the third difference signal.

6. The method according to claim 2, characterized in that, The signal synthesis operation includes: The first signal is subjected to a first filter to obtain the second frequency band component in the first signal; The pickup signal is subjected to a second filter to obtain the component of the first frequency band in the pickup signal; and The components of the first frequency band and the components of the second frequency band are combined to obtain the composite signal.

7. The method according to claim 6, characterized in that, The first filter and the second filter are complementary filters.

8. The method according to claim 1, characterized in that, The first target operation includes: The first signal is subjected to a first filter to obtain a first sub-signal corresponding to the first frequency band, and the first signal is subjected to a second filter to obtain a second sub-signal corresponding to the second frequency band. The second signal is subjected to the first filtering to obtain a third sub-signal in the second signal corresponding to the first frequency band; The target sub-signal is obtained by performing zero-point differential on the first sub-signal and the third sub-signal; and The second sub-signal and the target sub-signal are combined to obtain the composite signal.

9. The method according to claim 1, characterized in that, The phase of the signal component corresponding to the target sound in the second signal is earlier than or equal to the phase of the signal component corresponding to the target sound in the first signal.

10. The method according to claim 1, characterized in that, The frequencies in the first frequency band are higher than the frequencies in the second frequency band.

11. The method according to claim 1, characterized in that, The method further includes: Based on the first signal and the second signal, determine the background noise characteristics corresponding to the current environment; and Based on the noise floor characteristics, the frequency range corresponding to the first frequency band and the frequency range corresponding to the second frequency band are determined.

12. The method according to claim 1, characterized in that, The speaker module includes a first speaker and a second speaker. The first frequency band includes a first sub-frequency band and a second sub-frequency band. The sound-emitting frequency band of the first speaker includes the first sub-frequency band, and the sound-emitting frequency band of the second speaker includes the second sub-frequency band. The signal of the first sub-frequency band in the integrated signal comes from the first pickup result signal obtained by the sound sensor module in the first pickup state, and the first pickup state corresponds to the zero-point pickup direction of the sound sensor module pointing to the first speaker. as well as The signal of the second sub-frequency band in the integrated signal comes from the second pickup result signal obtained by the sound sensor module in the second pickup state. The second pickup state corresponds to the zero-point pickup direction of the sound sensor module pointing to the second speaker. The pickup direction patterns corresponding to the first pickup state and the second pickup state are different.

13. The method according to claim 12, characterized in that, The frequency in the first sub-band is lower than the frequency in the second sub-band; and The pickup direction pattern corresponding to the first pickup state is a heart shape, and the pickup direction pattern corresponding to the second pickup state is a figure-eight shape.

14. The method according to claim 1, characterized in that, The second target operation includes: amplifying the gain of the composite signal and sending the amplified signal to the speaker module so that the speaker module emits sound.

15. The method according to claim 1, characterized in that, The speaker module and the sound sensor module are deployed on the first acoustic device, and the first acoustic device is communicatively connected to the second acoustic device; as well as The second target operation includes sending the composite signal to the second acoustic device to reduce the echo of the second acoustic device.

16. An acoustic system, characterized in that, include: The speaker module receives input signals and outputs the target sound during operation. A sound sensor module includes at least a first sound sensor and a second sound sensor. When the first sound sensor is working, it collects ambient sound and generates a first signal. When the second sound sensor is working, it collects the ambient sound and generates a second signal. The ambient sound includes at least the target sound. as well as The signal processing circuit is connected to the sound sensor module and performs the method according to any one of claims 1-15 when in operation.

17. The acoustic system according to claim 16, characterized in that, The signal processing circuit includes: At least one storage medium storing at least one instruction set for signal processing; and At least one processor is communicatively connected to the sound sensor module and the at least one storage medium, wherein, when the acoustic system is running, the at least one processor reads the at least one instruction set and executes the method of any one of claims 1-15 according to the instructions of the at least one instruction set.

18. The acoustic system according to claim 16, characterized in that, The acoustic system can be any one of a hearing aid system, a loudspeaker system, a headphone system, a telephone system, or a conference system.

19. The acoustic system according to claim 16, characterized in that, The acoustic system is a hearing aid system. The acoustic system also includes a housing, within which the speaker module, the sound sensor module, and the signal processing circuit are housed. When the acoustic system is worn on a user's head, the sound output end of the speaker module faces the user's head, and the pickup end of at least one sound sensor in the sound sensor module is located on the side of the housing away from the user's head.

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