A microphone

Abstract

The present disclosure provides a microphone. The microphone can include at least one acoustic-electric transducer and an acoustic structure. The acoustic-electric transducer can be configured to convert a sound signal into an electric signal. The acoustic structure can include a sound guide tube and an acoustic cavity, the acoustic cavity can be in acoustic communication with the acoustic-electric transducer and in acoustic communication with an outside of the microphone through the sound guide tube. The acoustic structure can have a first resonance frequency, the acoustic-electric transducer can have a second resonance frequency, and an absolute value of a difference between the first resonance frequency and the second resonance frequency can be no less than 100 Hz. The microphone provided by the present disclosure can increase resonance peaks of different frequency ranges in a microphone system by setting different acoustic structures, thereby improving the sensitivity of the microphone near multiple resonance peaks and further improving the sensitivity of the microphone in a whole wide frequency band.

Description

Technical Field

[0001] This specification relates to the field of acoustic devices, and in particular to a microphone. Background Technology

[0002] Filtering and frequency division techniques have wide applications in signal processing. As the foundation for signal processing technologies such as speech recognition, noise reduction, and signal enhancement, they are widely used in electroacoustics, communications, image coding, echo cancellation, and radar sorting. Traditional filtering or frequency division methods employ hardware circuits or software programs. Hardware-based filtering or frequency division is easily affected by the characteristics of electronic components, and the circuits are relatively complex. Software-based filtering or frequency division is computationally complex, time-consuming, and requires significant computing resources. Furthermore, traditional signal filtering or frequency division techniques can be affected by the sampling frequency, easily causing signal distortion and introducing noise.

[0003] Therefore, it is necessary to provide a more efficient signal frequency division device and method, simplify the structure of acoustic devices, and improve the quality factor (Q value) and sensitivity of acoustic devices. Summary of the Invention

[0004] One aspect of this specification provides a microphone. The microphone may include at least one acoustic-to-electrical transducer and an acoustic structure. The at least one acoustic-to-electrical transducer can be used to convert sound signals into electrical signals. The acoustic structure may include a sound guide tube and an acoustic cavity, the acoustic cavity being acoustically connected to the acoustic-to-electrical transducer and acoustically connected to the outside of the microphone through the sound guide tube. The acoustic structure may have a first resonant frequency, the acoustic-to-electrical transducer may have a second resonant frequency, and the absolute value of the difference between the first resonant frequency and the second resonant frequency may be not less than 100 Hz.

[0005] In some embodiments, the sensitivity of the microphone's response at the first resonant frequency may be greater than the sensitivity of the at least one acoustic-electric transducer's response at the first resonant frequency.

[0006] In some embodiments, the first resonant frequency is related to the structural parameters of the acoustic structure, which may include the shape of the sound guide tube, the size of the sound guide tube, the size of the acoustic cavity, the acoustic resistance of the sound guide tube or the acoustic cavity, the roughness of the inner surface of the sidewall of the sound guide tube, or combinations thereof.

[0007] In some embodiments, the at least one acoustic-to-electric transducer and the acoustic cavity may be located within the housing, and the housing may include a first sidewall for forming the acoustic cavity.

[0008] In some embodiments, the first end of the sound guide tube may be located on the first sidewall, and the second end of the sound guide tube may be located away from the first sidewall and outside the housing.

[0009] In some embodiments, the first end of the sound guide tube may be located on the first sidewall, and the second end of the sound guide tube may be located away from the first sidewall and extend into the acoustic cavity.

[0010] In some embodiments, the first end of the sound guide tube may be located away from the first sidewall and outside the housing, and the second end of the sound guide tube may extend into the acoustic cavity.

[0011] In some embodiments, the sidewall of the sound guide tube and the central axis of the sound guide tube may form an inclination angle, the angle of which may be in the range of 0° to 20°.

[0012] In some embodiments, an acoustic impedance structure may be provided in the acoustic tube or the acoustic cavity, and the acoustic impedance structure may be used to adjust the bandwidth of the acoustic structure.

[0013] In some embodiments, the acoustic impedance value of the acoustic impedance structure can range from 1 MKS Rayls to 100 MKS Rayls.

[0014] In some embodiments, the thickness of the acoustic resistive structure can be from 20 micrometers to 300 micrometers, the pore size of the acoustic resistive structure can be from 20 micrometers to 300 micrometers, and the porosity of the acoustic resistive structure can be from 30% to 50%.

[0015] In some embodiments, the acoustic impedance structure may be disposed at one or more of the following locations: the outer surface of the sidewall forming the sound guide tube away from the first sidewall, the interior of the sound guide tube, the inner surface of the first sidewall, in the acoustic cavity, the inner surface of the second sidewall for forming the aperture of the acoustic-electric converter, the outer surface of the second sidewall, and the interior of the aperture of the acoustic-electric converter.

[0016] In some embodiments, the aperture of the sound guide tube may not be greater than twice the length of the sound guide tube.

[0017] In some embodiments, the aperture of the sound guide tube can be from 0.1 mm to 10 mm, and the length of the sound guide tube can be from 1 mm to 8 mm.

[0018] In some embodiments, the roughness of the inner surface of the sidewall forming the sound guide tube may not be greater than 0.8.

[0019] In some embodiments, the inner diameter of the acoustic cavity may be no less than the thickness of the acoustic cavity.

[0020] In some embodiments, the inner diameter of the acoustic cavity can be from 1 mm to 20 mm, and the thickness of the acoustic cavity can be from 1 mm to 20 mm.

[0021] In some embodiments, the microphone may further include a second acoustic structure, which may include a second sound guide tube and a second acoustic cavity. The second acoustic cavity may be acoustically connected to the outside of the microphone through the second sound guide tube. The second acoustic structure may have a third resonant frequency, which may be different from the first resonant frequency.

[0022] In some embodiments, when the third resonant frequency is greater than the first resonant frequency, the difference between the sensitivity of the microphone at the third resonant frequency and the sensitivity of the acoustic-electric transducer at the third resonant frequency can be greater than the difference between the sensitivity of the microphone at the first resonant frequency and the sensitivity of the acoustic-electric transducer at the first resonant frequency.

[0023] In some embodiments, the second acoustic cavity can be acoustically connected to the acoustic cavity through the sound guide tube.

[0024] In some embodiments, the microphone may further include a third acoustic structure, which may include a third sound guide tube, a fourth sound guide tube, and a third acoustic cavity. The acoustic cavity is acoustically connected to the third acoustic cavity via the third sound guide tube. The second acoustic cavity is acoustically connected to the outside of the acoustic microphone via the second sound guide tube and to the third acoustic cavity via the fourth sound guide tube. The third acoustic cavity is acoustically connected to the electroacoustic transducer. The third acoustic structure may have a fourth resonant frequency, which may be different from the third resonant frequency and the first resonant frequency.

[0025] In some embodiments, the at least one acoustic-electric transducer may include a second acoustic-electric transducer, and the second acoustic cavity may be acoustically connected to the second acoustic-electric transducer.

[0026] In some embodiments, the microphone may include an electret microphone or a silicon microphone.

[0027] Another aspect of this specification provides a microphone. The microphone may include at least one acoustic-to-electrical transducer, a first acoustic structure, and a second acoustic structure. The at least one acoustic-to-electrical transducer can be used to convert sound signals into electrical signals. The first acoustic structure may include a first sound guide tube and a first acoustic cavity, and the second acoustic structure may include a second sound guide tube and a second acoustic cavity. The first sound guide tube may be acoustically connected to the outside of the microphone, and the first acoustic cavity may be connected to the second acoustic cavity through the second sound guide tube. The second acoustic cavity may be acoustically connected to the acoustic-to-electrical transducer. The first acoustic structure may have a first resonant frequency, and the second acoustic structure may have a second resonant frequency, wherein the first resonant frequency may be different from the second resonant frequency.

[0028] In some embodiments, the range of the first resonant frequency or the second resonant frequency can be 100Hz-15000Hz.

[0029] In some embodiments, the first resonant frequency may be related to the structural parameters of the first acoustic structure, and the second resonant frequency may be related to the structural parameters of the second acoustic structure.

[0030] Additional features will be set forth in part in the description which follows, and will become apparent to those skilled in the art upon consulting the following description and the accompanying drawings, or may be learned by the generation or operation of examples. The features of the invention can be realized and obtained by practice or use of various aspects of the methods, tools, and combinations set forth in the following detailed examples. Attached Figure Description

[0031] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0032] Figure 1 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0033] Figure 2A These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0034] Figure 2B These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0035] Figure 3 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0036] Figure 4This is a schematic diagram of the frequency response curve of an exemplary microphone according to some embodiments of this specification;

[0037] Figure 5 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0038] Figure 6 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0039] Figure 7 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0040] Figure 8 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0041] Figure 9 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0042] Figure 10 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0043] Figure 11 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0044] Figure 12 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0045] Figure 13 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0046] Figure 14 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0047] Figure 15 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0048] Figure 16 This is a schematic diagram of the frequency response curve of an exemplary microphone according to some embodiments of this specification;

[0049] Figure 17 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0050] Figure 18 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0051] Figure 19These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0052] Figure 20 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification;

[0053] Figure 21 These are frequency response curves of exemplary microphones shown in some embodiments of this specification;

[0054] Figure 22 These are frequency response curves of exemplary microphones shown in some embodiments of this specification. Detailed Implementation

[0055] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. It should be understood that these exemplary embodiments are given merely to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0056] It should be understood that the terms “system,” “device,” “unit,” and / or “component,” “assembly,” and “element” used herein are a method of distinguishing different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0057] Various terms are used to describe spatial and functional relationships between elements (e.g., between parts), including “connection,” “joint,” “interface,” and “coupled.” Unless explicitly described as “direct,” when describing a relationship between first and second elements in this specification, the relationship includes a direct relationship where no other intermediate elements exist between the first and second elements, and an indirect relationship where one or more intermediate elements exist (spatially or functionally) between the first and second elements. Conversely, when an element is referred to as “directly” connected, joined, interfaced, or coupled to another element, no intermediate element exists. Furthermore, spatial and functional relationships between elements can be achieved in various ways. For example, a mechanical connection between two elements may include a welded connection, a keyed connection, a pin connection, an interference fit connection, etc., or any combination thereof. Other terms used to describe relationships between elements should be interpreted in a similar manner (e.g., “between,” “with,” “adjacent,” and “directly adjacent,” etc.).

[0058] It should be understood that the terms "first," "second," "third," etc., used in this document can be used to describe various elements. These are only used to distinguish one element from another and are not intended to limit the scope of the elements. For example, a first element can also be called a second element, and similarly, a second element can also be called a first element.

[0059] As indicated in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. The term "based on" means "at least partially based on." The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment." Definitions of other terms will be given in the following description. Hereinafter, without loss of generality, the term "microphone" or "voice transducer" will be used in the description of filtering / frequency division related techniques in this invention. This description is merely one form of conductive application, and for those skilled in the art, "voice transducer" or "microphone" may be replaced by other similar terms, such as "hydrophone," "transducer," "acoustic-optical modulator," or "acoustic-electrical conversion device," etc. For those skilled in the art, after understanding the basic principles of a microphone device, various modifications and changes in form and detail may be made to the specific methods and steps of implementing the microphone without departing from these principles. However, such modifications and changes are still within the scope of this specification.

[0060] This specification provides a microphone. The microphone may include at least one acoustic-to-electrical transducer and an acoustic structure. The at least one acoustic-to-electrical transducer can be used to convert sound signals into electrical signals. The acoustic structure includes a sound guide tube and an acoustic cavity. The acoustic cavity is acoustically connected to the acoustic-to-electrical transducer and to the external acoustic environment of the microphone via the sound guide tube. The sound guide tube and acoustic cavity of the acoustic structure can form a filter with the function of adjusting the frequency components of sound. This scheme uses the structural characteristics of the acoustic structure itself to filter and / or divide subbands of the sound signal, eliminating the need for a large number of complex circuits to implement filtering, thus reducing the difficulty of circuit design. The filtering characteristics of the acoustic structure are determined by the physical characteristics of its structure, and the filtering process occurs in real time.

[0061] In some embodiments, the acoustic structure can "amplify" sound at its corresponding resonant frequency. The resonant frequency of the acoustic structure can be adjusted by changing its structural parameters. The structural parameters of the acoustic structure may include the shape of the sound guide tube, the size of the sound guide tube, the size of the acoustic cavity, the acoustic resistance of the sound guide tube or the acoustic cavity, the roughness of the inner surface of the sidewall of the sound guide tube, the thickness of the sound-absorbing material in the sound guide tube, or combinations thereof.

[0062] In some embodiments, by arranging multiple acoustic structures with different resonant frequencies in parallel, series, or a combination thereof, frequency components corresponding to different resonant frequencies in the sound signal can be filtered out separately, thereby achieving sub-band frequency division of the sound signal. In this case, the frequency response of the microphone can be regarded as a higher signal-to-noise ratio, flatter frequency response curve formed by fusing the frequency responses of different acoustic structures (e.g., Figure 22 The frequency response curve shown is 2210. On the one hand, the microphone provided in the embodiments of this specification can perform sub-band frequency division processing on the full-band signal through its own structure without utilizing hardware circuits (e.g., filtering circuits) or software algorithms. This avoids the problems of complex hardware circuit design and high computational resource consumption, signal distortion, and noise introduction caused by software algorithms, thereby reducing the complexity and production cost of the microphone. On the other hand, the microphone provided in the embodiments of this specification can output a high signal-to-noise ratio and a flatter frequency response curve, improving the signal quality of the microphone. In addition, by setting different acoustic structures, resonance peaks in different frequency ranges can be added to the microphone system, improving the microphone's sensitivity near multiple resonance peaks, thereby improving the microphone's sensitivity across the entire bandwidth.

[0063] Figure 1 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification. Figure 1 As shown, the microphone 100 may include an acoustic structure 110, at least one acoustic-to-electrical converter 120, a sampler 130, and a signal processor 140.

[0064] In some embodiments, microphone 100 may include any sound signal processing device that converts sound signals into electrical signals, such as a microphone, hydrophone, acousto-optic modulator, or other sound-to-electric conversion device. In some embodiments, based on the transduction principle, microphone 110 may include a dynamic microphone, ribbon microphone, condenser microphone, piezoelectric microphone, electret microphone, electromagnetic microphone, carbon particle microphone, or any combination thereof. In some embodiments, based on the sound acquisition method, microphone 110 may include a bone conduction microphone, air conduction microphone, or a combination thereof. In some embodiments, based on the manufacturing process, microphone 110 may include an electret microphone, silicon microphone, or the like. In some embodiments, microphone 100 may be installed on devices with sound pickup capabilities, such as mobile devices (e.g., mobile phones, voice recorders, etc.), tablet computers, laptop computers, in-vehicle devices, monitoring devices, medical devices, sports equipment, toys, and wearable devices (e.g., headphones, helmets, glasses, necklaces, etc.).

[0065] Acoustic structure 110 can transmit external sound signals to at least one acoustic-to-electric converter 120. As the sound signal passes through acoustic structure 110, it can be modulated (e.g., filtered, its bandwidth altered, or its frequency amplified). In some embodiments, acoustic structure 110 may include a sound guide tube and an acoustic cavity. The acoustic cavity is acoustically connected to acoustic-to-electric converter 120 and is used to transmit the modulated acoustic signal to the converter 120. The acoustic cavity can be acoustically connected to the external environment of microphone 100 via the sound guide tube for receiving sound signals. The sound signal can originate from any sound source capable of generating an audio signal. The sound source can be a living organism (e.g., the user of microphone 100), a non-living organism (e.g., a CD player, television, stereo, etc.), or a combination thereof. In some embodiments, the sound signal may include ambient sound.

[0066] In some embodiments, the acoustic structure 110 has a first resonant frequency, which means that the frequency component of the sound signal at the first resonant frequency will resonate, thereby increasing the volume of that frequency component transmitted to the acoustic-to-electric converter 120. Therefore, the arrangement of the acoustic structure 110 can cause the frequency response curve of the microphone 100 to generate a resonant peak at the first resonant frequency, thereby improving the sensitivity of the microphone 100 within a certain frequency band including the first resonant frequency. For details on the effect of the acoustic structure 110 on the frequency response curve of the microphone 100, please refer to [link to relevant documentation]. Figures 2A-22 And its related descriptions.

[0067] In some embodiments, the number of acoustic structures 110 in the microphone 100 can be set according to actual needs. For example, the microphone 100 may include multiple (e.g., 2, 3, 5, 6-24, etc.) acoustic structures 110. In some embodiments, the multiple acoustic structures 110 in the microphone 100 may have different frequency responses; for example, the multiple acoustic structures 110 in the microphone 100 may have different resonant frequencies and / or bandwidths. Bandwidth can refer to the frequency range between 3dB points on the frequency response curve. In some embodiments, after processing by multiple acoustic structures 100, the sound signal can be frequency-divided to generate multiple sub-band sound signals (e.g., sub-band sound signal 1111, sub-band sound signal 1112, ..., sub-band sound signal 111n) with different bandwidths. A sub-band sound signal is a signal whose bandwidth is smaller than the bandwidth of the original sound signal. The bandwidth of the sub-band sound signal can be within the bandwidth of the sound signal. For example, the frequency range of the sound signal can be 100Hz-20000Hz. An acoustic structure 110 can be set up to filter the sound signal and generate a sub-band sound signal with a frequency range of 100Hz-200Hz. Alternatively, 11 acoustic structures 110 can be set up to divide the sound signal into 11 sub-band sound signals with frequency ranges of 500Hz-700Hz, 700Hz-1000Hz, 1000Hz-1300Hz, 1300Hz-1700Hz, 1700Hz-2200Hz, 2200Hz-3000Hz, 3000Hz-3800Hz, 3800Hz-4700Hz, 4700Hz-5700Hz, 5700Hz-7000Hz, and 7000Hz-12000Hz. For example, 16 acoustic structures 110 can be set up to divide the sound signal into 16 sub-band sound signals, with frequency ranges of 500Hz-640Hz, 640Hz-780Hz, 780Hz-930Hz, 940Hz-1100Hz, 1100Hz-1300Hz, 1300Hz-1500Hz, 1500Hz-1750Hz, 1750Hz-1900Hz, 1900Hz-2350Hz, 2350Hz-2700Hz, 2700Hz-3200Hz, 3200Hz-3800Hz, 3800Hz-4500Hz, 4500Hz-5500Hz, 5500Hz-6600Hz, and 6600Hz-8000Hz.For example, 24 acoustic structures 110 can be set up to divide the sound signal into 24 sub-band sound signals, with frequency ranges of 20Hz-120Hz, 120Hz-210Hz, 210Hz-320Hz, 320Hz-410Hz, 410Hz-500Hz, 500Hz-640Hz, 640Hz-780Hz, 780Hz-930Hz, 940Hz-1100Hz, 1100Hz-1300Hz, 1300Hz-150Hz. 0, 1500Hz-1750, 1750Hz-1900, 1900Hz-2350, 2350Hz-2700Hz, 2700Hz-3200Hz, 3200Hz-3800Hz, 3800Hz-4500Hz, 4500Hz-5500Hz, 5500Hz-6600Hz, 6600Hz-7900Hz, 7900Hz-9600Hz, 9600Hz-12100Hz, 12100Hz-16000Hz. Using acoustic structures for filtering and frequency division allows for real-time filtering and / or frequency division of audio signals, reducing noise introduction during subsequent hardware processing and preventing signal distortion.

[0068] In some embodiments, the plurality of acoustic structures 110 in the microphone 100 may be arranged in parallel, in series, or in a combination thereof. Details regarding the arrangement of the plurality of acoustic structures can be found in [reference needed]. Figure 17-20 And its related descriptions.

[0069] Acoustic structure 110 can be connected to acoustic-to-electric converter 120 to transmit the sound signal regulated by acoustic structure 110 to acoustic-to-electric converter 120 for conversion into an electrical signal. In some embodiments, acoustic-to-electric converter 120 may include a capacitive acoustic-to-electric converter, a piezoelectric acoustic-to-electric converter, or a combination thereof. In some embodiments, vibrations of the sound signal (e.g., air vibrations, solid vibrations, liquid vibrations, magnetostrictive vibrations, electrostrictive vibrations, etc.) may cause changes in one or more parameters of acoustic-to-electric converter 120 (e.g., capacitance, charge, acceleration, light intensity, frequency response, etc., or a combination thereof), and the changed parameters can be detected using electrical methods and an electrical signal corresponding to the vibration can be output. For example, a piezoelectric acoustic-to-electric converter may be an element that converts changes in the measured non-electrical quantity (e.g., pressure, displacement, etc.) into changes in voltage. For example, a piezoelectric acoustic-to-electric converter may include a cantilever beam structure (or diaphragm structure) that can deform under the action of the received sound signal, and the inverse piezoelectric effect caused by the deformed cantilever beam structure can generate an electrical signal. For example, a capacitive acoustic-to-electric transducer can be a component that converts changes in the measured non-electrical quantity (e.g., displacement, pressure, light intensity, acceleration, etc.) into changes in capacitance. For instance, a capacitive acoustic-to-electric transducer may include a first cantilever beam structure and a second cantilever beam structure. Under vibration, the first and second cantilever beam structures can deform to different degrees, thereby changing the distance between them. The first and second cantilever beam structures can convert the change in distance between them into a change in capacitance, thus realizing the conversion of vibration signals into electrical signals. In some embodiments, different acoustic-to-electric transducers 120 may have the same or different frequency responses. For example, acoustic-to-electric transducers 120 with different frequency responses can detect the same sound signal, and different acoustic-to-electric transducers 120 can generate sub-band signals with different resonant frequencies.

[0070] In some embodiments, the number of acoustic-to-electric transducers 120 can be one or more. For example, the acoustic-to-electric transducers 120 may include acoustic-to-electric transducers 121, 122, ..., 12n. In some embodiments, one or more of the acoustic-to-electric transducers 120 can be connected to the acoustic structure 110 in various ways. For example, multiple acoustic structures 110 in the microphone 100 can be connected to the same acoustic-to-electric transducer 120. As another example, each of the multiple acoustic structures 110 can be connected to one acoustic-to-electric transducer 120.

[0071] In some embodiments, one or more of the acoustic-to-electric converters in the acoustic-to-electric converter 120 can be used to convert the sound signals transmitted by the acoustic structure 110 into electrical signals. For example, the acoustic-to-electric converter 120 can convert the filtered sound signals of the acoustic structure 110 into corresponding electrical signals. As another example, multiple acoustic-to-electric converters in the acoustic-to-electric converter 120 can respectively convert the sub-band acoustic signals after frequency division of multiple acoustic structures 110 into corresponding sub-band electrical signals. As an example only, the acoustic-to-electric converter 120 can respectively convert sub-band acoustic signals 1111, 1112, ..., 111n into sub-band electrical signals 1211, 1212, ..., 121n.

[0072] The acoustic-to-electric converter 120 can transmit the generated sub-electro-signal (or electrical signal) to the sampler 130. In some embodiments, one or more sub-electro-signals can be transmitted separately through different parallel line media. In some embodiments, multiple sub-electro-signals can also be output in a specific format according to specific protocol rules through a shared line media. In some embodiments, the specific protocol rules may include, but are not limited to, one or more of direct transmission, amplitude modulation, frequency modulation, etc. In some embodiments, the line media may include, but are not limited to, one or more of coaxial cable, communication cable, flexible cable, spiral cable, non-metallic sheathed cable, metallic sheathed cable, multi-core cable, twisted pair cable, ribbon cable, shielded cable, telecommunication cable, two-strand cable, parallel two-core conductor, twisted pair, optical fiber, infrared, electromagnetic waves, sound waves, etc. In some embodiments, the specific format may include, but is not limited to, one or more of CD, WAVE, AIFF, MPEG-1, MPEG-2, MPEG-3, MPEG-4, MIDI, WMA, RealAudio, VQF, AMR, APE, FLAC, AAC, etc. In some embodiments, the transmission protocol may include, but is not limited to, one or more of AES3, EBU, ADAT, I2S, TDM, MIDI, CobraNet, Ethernet AVB, Dante, ITU-T G.728, ITU-T G.711, ITU-T G.722, ITU-T G.722.1, ITU-T G.722.1 Annex C, AAC-LD, etc.

[0073] Sampler 130 can communicate with acoustic-to-electric converter 120 to receive one or more sub-charged signals generated by acoustic-to-electric converter 120 and sample one or more sub-charged signals to generate corresponding digital signals.

[0074] In some embodiments, sampler 130 may include one or more samplers (e.g., sampler 131, sampler 132, ..., sampler 13n). Each sampler may sample each sub-band signal. For example, sampler 131 may sample sub-band signal 1211 to generate digital signal 1311. As another example, sampler 132 may sample sub-band signal 1212 to generate digital signal 1312. Yet another example, sampler 13n may sample sub-band signal 121n to generate digital signal 131n.

[0075] In some embodiments, sampler 130 may use bandpass sampling to sample the sub-band signal. For example, the sampling frequency of sampler 130 may be configured according to the bandwidth (3dB) of the sub-band signal. In some embodiments, sampler 130 may sample the sub-band signal at a sampling frequency not less than twice the highest frequency in the sub-band signal. In some embodiments, sampler 130 may sample the sub-band signal at a sampling frequency not less than twice and not more than four times the highest frequency in the sub-band signal. Compared to conventional sampling methods (e.g., bandwidth sampling, low-pass sampling, etc.), using bandpass sampling allows sampler 130 to sample at a relatively lower sampling frequency, thereby reducing the difficulty and cost of the sampling process.

[0076] In some embodiments, the sampling frequency of sampler 130 can affect the cutoff frequency of sampler 130. In some embodiments, a higher sampling frequency results in a higher cutoff frequency and a wider sampleable frequency band. When signal processor 140 processes the digital signal generated by sampler 130, for the same number of Fourier transform points, a higher sampling frequency corresponds to a lower frequency resolution. Therefore, sampler 130 can use different sampling frequencies to sample sub-band signals located in different frequency ranges. For example, for sub-band signals located in the low-frequency range (e.g., sub-band signals with frequencies less than a first frequency threshold), sampler 130 can use a lower sampling frequency, resulting in a lower sampling cutoff frequency. As another example, for sub-band signals located in the mid-to-high frequency range (e.g., sub-band signals with frequencies greater than a second frequency threshold but less than a third frequency threshold), sampler 130 can use a higher sampling frequency, resulting in a relatively higher sampling cutoff frequency. Furthermore, the sampling cutoff frequency of sampler 130 can be 0Hz-500Hz higher than the 3dB bandwidth frequency point of the sub-band's resonant frequency.

[0077] Sampler 130 can transmit one or more generated digital signals to signal processor 140. The transmission of one or more digital signals can be performed separately through different parallel line media. In some embodiments, one or more digital signals can also share a single line medium and be transmitted in a specific format according to specific protocol rules. For information on digital signal transmission, see the section on sub-band signal transmission.

[0078] Signal processor 140 can receive and process data from other components of microphone 100. For example, signal processor 140 can process digital signals transmitted from sampler 130. In some embodiments, signal processor 140 can process each sub-band signal transmitted from sampler 130 individually to generate a corresponding digital signal. For example, different sub-band signals (e.g., sub-band signals processed by different acoustic structures, acousto-electric transducers, etc.) may have different phases, corresponding frequencies, etc., and signal processor 140 can process each sub-band signal. In some embodiments, signal processor 140 can acquire multiple sub-band signals from sampler 130 and process (e.g., fuse) the multiple sub-band signals to generate a broadband signal for microphone 100.

[0079] In some embodiments, the signal processor 140 may further include one or more of an equalizer, a dynamic range controller, a phase processor, etc. In some embodiments, the equalizer may be configured to gain and / or attenuate the digital signal output from the sampler 130 according to a specific frequency band (e.g., the frequency band corresponding to the digital signal). Gaining the digital signal means increasing the signal amplification; attenuating the digital signal means decreasing the signal amplification. In some embodiments, the dynamic range controller may be configured to compress and / or amplify the digital signal. Compressing and / or amplifying the sub-band frequency-division electrical signal means decreasing and / or increasing the ratio between the input signal and the output signal in the microphone 100. In some embodiments, the phase processor may be configured to adjust the phase of the digital signal. In some embodiments, the signal processor 140 may be located inside the microphone 100. For example, the signal processor 140 may be located in an acoustic cavity independently formed by the housing structure of the microphone 100. In some embodiments, the signal processor 140 may also be located in other electronic devices, such as headphones, mobile devices, tablet computers, laptops, etc., or any combination thereof. In some embodiments, mobile devices may include, but are not limited to, mobile phones, smart home devices, smart mobile devices, etc., or any combination thereof. In some embodiments, smart home devices may include control devices for smart appliances, smart monitoring devices, smart TVs, smart cameras, etc., or any combination thereof. In some embodiments, smart mobile devices may include smartphones, personal digital assistants (PDAs), gaming devices, navigation devices, POS devices, etc., or any combination thereof.

[0080] The description of the microphone 100 above is for illustrative purposes only and is not intended to limit the scope of this specification. Various changes and modifications can be made by those skilled in the art based on the description herein. For example, the sampler 130 and the signal processor 140 can be integrated into a single component (e.g., an application-specific integrated circuit (ASIC)). These changes and modifications remain within the scope of this specification.

[0081] Figure 2A These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification. Figure 2A As shown, the microphone 200 may include a housing 210, at least one acoustic-to-electrical transducer 220, and an acoustic structure 230.

[0082] The housing 210 may be configured to house one or more components of the microphone 200 (e.g., at least one acoustic-to-electric transducer 220, at least a portion of the acoustic structure 230, etc.). In some embodiments, the housing 210 may be a regular structure such as a cuboid, cylinder, prism, or frustum, or other irregular structures. In some embodiments, the housing 210 is a hollow structure that may form one or more acoustic cavities, such as acoustic cavity 231 and acoustic cavity 240. Acoustic cavity 240 may house the acoustic-to-electric transducer 220 and an application-specific integrated circuit 250. Acoustic cavity 231 may house or be at least a portion of the acoustic structure 230. In some embodiments, the housing 210 may include only one acoustic cavity. As an example, Figure 2B This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. The housing 210 of microphone 205 may form an acoustic cavity 240. One or more components of microphone 205, such as acoustic-to-electric transducer 220, application-specific integrated circuit 250, and at least a portion of acoustic structure 230 (e.g., acoustic cavity 231), may be located within acoustic cavity 231. In this case, the acoustic cavity 240 formed by housing 210 may coincide with the acoustic cavity 231 of acoustic structure 230. Acoustic structure 230 may be in direct acoustic communication with acoustic transducer 220. Direct acoustic communication between acoustic structure 230 and acoustic transducer 220 can be understood as follows: acoustic transducer 220 may include a "front cavity" and a "rear cavity," and sound signals in the "front cavity" or "rear cavity" may cause changes in one or more parameters of acoustic transducer 220. Figure 2A In the microphone 200 shown, the sound signal passes through the acoustic structure 230 (e.g., the sound guide tube 232 and the acoustic cavity 231), and then through the aperture 221 of the acoustic-electric converter 220 to the "rear cavity" of the acoustic-electric converter 220, causing a change in one or more parameters of the acoustic-electric converter 220. Figure 2BIn the microphone 205 shown, the acoustic cavity 240 formed by the housing 210 coincides with the acoustic cavity 231 of the acoustic structure 230. It can be considered that the "front cavity" of the acoustic-to-electric converter 220 coincides with the acoustic cavity 231 of the acoustic structure. The sound signal, after passing through the acoustic structure 230, directly causes a change in one or more parameters of the acoustic-to-electric converter 220. For ease of description, this specification mainly assumes that the acoustic cavity 231 and the acoustic cavity 240 do not coincide (e.g., ...). Figure 2A As shown, at least one acoustic-to-electric converter 220 is disposed in an acoustic cavity 240. The overlap between acoustic cavities 231 and 240 can be the same or similar.

[0083] In some embodiments, the material of the housing 210 may include, but is not limited to, one or more of the following: metal, alloy material, polymer material (e.g., acrylonitrile-butadiene-styrene copolymer, polyvinyl chloride, polycarbonate, polypropylene, etc.).

[0084] In some embodiments, at least one acoustic-to-electrical converter 220 can be used to convert an acoustic signal into an electrical signal. The at least one acoustic-to-electrical converter 220 may include one or more apertures 221. An acoustic structure 230 can communicate with the at least one acoustic-to-electrical converter 220 through one or more apertures 221 of the acoustic-to-electrical converter 220, and transmit the acoustic signal regulated by the acoustic structure 230 to the acoustic-to-electrical converter 220. For example, an external acoustic signal picked up by the microphone 200, after being regulated by the acoustic structure 230 (e.g., filtered, frequency divided, amplified, etc.), can enter the cavity (if any) of the acoustic converter 220 through the aperture 221. The acoustic-to-electrical converter 220 can then pick up the acoustic signal and convert it into an electrical signal.

[0085] In some embodiments, the acoustic structure 230 may include an acoustic cavity 231 and a sound guide tube 232. The acoustic structure 230 can communicate with the outside of the microphone 200 through the sound guide tube 232. In some embodiments, the housing 210 may include a plurality of sidewalls for forming a space within the housing. The sound guide tube 232 may be located on a first sidewall 211 of the housing 210 for forming the acoustic cavity 231. Specifically, a first end of the sound guide tube 232 (e.g., the end closer to the acoustic cavity 231) may be located on the first sidewall 211 of the housing 210, and a second end of the sound guide tube 232 (e.g., the end relatively away from the acoustic cavity 231) may be located away from the first sidewall 211 and outside the housing 210. External sound signals can enter the sound guide tube 232 from the second end of the sound guide tube 232 and be transmitted from the first end of the sound guide tube 232 to the acoustic cavity 231. In some embodiments, the sound guide tube 232 of the acoustic structure 230 may also be disposed in other suitable locations; for information on the location of the sound guide tube, please refer to [reference needed]. Figures 5 to 9 And its related descriptions.

[0086] In some embodiments, the acoustic structure 230 may have a first resonant frequency, meaning that the component of the sound signal at the first resonant frequency will resonate within the acoustic structure 230. In some embodiments, the first resonant frequency is related to the structural parameters of the acoustic structure 230. The structural parameters of the acoustic structure 230 may include the shape of the sound guide tube 232, the size of the sound guide tube 232, the size of the acoustic cavity 231, and the acoustic resistance of the sound guide tube 232 or the acoustic cavity 231, the roughness of the inner surface of the sidewall of the sound guide tube 232, the thickness of the sound-absorbing material (e.g., fiber material, foam material, etc.) in the sound guide tube, the stiffness of the inner wall of the acoustic cavity, etc., or combinations thereof. In some embodiments, by setting the structural parameters of the acoustic structure 230, the sound signal regulated by the acoustic structure 230 can have a resonant peak at the first resonant frequency after being converted into an electrical signal.

[0087] The shape of the sound guide 232 may include regular and / or irregular shapes such as cuboids, cylinders, and polygonal prisms. In some embodiments, the sound guide 232 may be formed by one or more sidewalls surrounding it. The shape of the sidewalls 233 of the sound guide 232 may be a regular and / or irregular structure such as a cuboid or cylinder.

[0088] In some embodiments, such as Figure 3 As shown, the length of the sidewall 233 of the sound guide 232 (e.g., Figure 2A In this embodiment, the length of the sidewall 233 along the X-axis (the sum of the length of the sidewall 233 and the diameter of the sound guide tube 232) can be the same as the length of the housing 210 along the X-axis. In some embodiments, the length of the sidewall 233 of the sound guide tube 232 can be different from the length of the housing 210. For example, Figure 3 These are schematic diagrams of exemplary microphones shown according to some embodiments of this specification, such as... Figure 3 As shown, the first end of the sound guide tube 232 is located on the first sidewall 211 of the housing 210, and the second end of the sound guide tube 232 is away from the first sidewall 211 and located outside the housing 210. The length of the hole sidewall 233 of the sound guide tube 232 along the X-axis is less than the length of the housing 210 along the X-axis.

[0089] The structural parameters such as the aperture and length of the sound guide tube 232, and the structural parameters such as the inner diameter, length, and thickness of the acoustic cavity 231, can be set as needed (e.g., target resonant frequency, target bandwidth, etc.). The length of the sound guide tube refers to the length along the central axis of the sound guide tube (e.g., ...). Figure 2A The total length of the sound guide 232 (in the Y-axis direction). In some embodiments, the length of the sound guide 232 can be the equivalent length of the sound guide, that is, the length of the sound guide along the central axis plus the product of the diameter of the sound guide and the length correction factor. Figure 2AAs shown, the length of the acoustic cavity 231 refers to its dimension along the X-axis. The thickness of the acoustic cavity 231 refers to its dimension along the Y-axis. In some embodiments, the aperture of the sound guide tube 232 may not be greater than twice the length of the sound guide tube 232. In some embodiments, the aperture of the sound guide tube 232 may not be greater than 1.5 times the length of the sound guide tube 232. For example, when the cross-section of the sound guide tube 232 (e.g., a cross-section perpendicular to the central axis of the sound guide tube (e.g., a cross-section parallel to the XZ plane) is circular, the aperture of the sound guide tube 232 can be in the range of 0.5 mm to 10 mm, and the length of the sound guide tube 232 can be in the range of 1 mm to 8 mm. As another example, when the cross-section of the sound guide tube 232 is circular, the aperture of the sound guide tube 232 can be 1 mm to 4 mm, and the length of the sound guide tube 232 can be 1 mm to 10 mm. In some embodiments, the inner diameter of the acoustic cavity 231 can be not less than the thickness of the acoustic cavity 231. In some embodiments, the acoustic... The inner diameter of the cavity 231 can be no less than 0.8 times the thickness of the acoustic cavity 231. For example, when the cross-section of the acoustic cavity 231 perpendicular to its length direction (e.g., the cross-section of the acoustic cavity 231 along a plane parallel to the YZ plane) is circular, the inner diameter of the acoustic cavity 231 can be in the range of 1 mm to 20 mm, and the thickness of the acoustic cavity 231 can be in the range of 1 mm to 20 mm. In some embodiments, when the cross-section of the acoustic cavity 231 is circular, the inner diameter of the acoustic cavity 231 can be in the range of 1 mm to 15 mm, and the thickness of the acoustic cavity 231 can be in the range of 1 mm to 10 mm.

[0090] It should be noted that the cross-sectional shape of the acoustic cavity 231 and / or the sound guide tube 232 is not limited to the circular shape described above, but can also be other shapes, such as rectangular, elliptical, pentagonal, etc. In some embodiments, when the cross-sectional shape of the acoustic cavity 231 and / or the sound guide tube 232 is other (non-circular), the inner diameter of the acoustic cavity 231 and / or the aperture (or thickness, length) of the sound guide tube 232 can be equivalent to the equivalent inner diameter or equivalent aperture. Taking the equivalent inner diameter as an example, an acoustic cavity 231 with other cross-sectional shapes can be represented by the inner diameter of an acoustic cavity and / or a sound guide tube with a circular cross-sectional shape and the same volume. For example, when the cross-section of the acoustic cavity 231 is square, the equivalent inner diameter of the acoustic cavity 231 can be in the range of 1 mm to 6 mm, and the thickness of the acoustic cavity 231 can be in the range of 1 mm to 4 mm. For example, when the cross-section of the acoustic cavity 231 is square, the equivalent inner diameter of the acoustic cavity 231 can be in the range of 1 mm to 5 mm, and the thickness of the acoustic cavity 231 can be in the range of 1 mm to 3 mm.

[0091] In some embodiments, the sidewall 233 of the sound guide 232 may be made of one or more materials. The material of the sidewall 233 may include, but is not limited to, one or more of semiconductor materials, metallic materials, metal alloys, and organic materials. In some embodiments, semiconductor materials may include, but are not limited to, silicon, silicon dioxide, silicon nitride, and silicon carbide. In some embodiments, metallic materials may include, but are not limited to, copper, aluminum, chromium, titanium, and gold. In some embodiments, metal alloys may include, but are not limited to, copper-aluminum alloys, copper-gold alloys, titanium alloys, and aluminum alloys. In some embodiments, organic materials may include, but are not limited to, polyimide (PI), parylene, polydimethylsiloxane (PDMS), silicone gel, and silicone.

[0092] The description of the microphone 200 above is for illustrative purposes only and is not intended to limit the scope of this specification. Various changes and modifications can be made by those skilled in the art based on the description in this specification. These changes and modifications are still within the scope of this specification.

[0093] Figure 4 This is a schematic diagram of the frequency response curves of an exemplary microphone according to some embodiments of this specification. Figure 4 As shown, frequency response curve 410 is the frequency response curve of the acoustic-electric converter (e.g., acoustic-electric converter 220), and frequency response curve 420 is the frequency response curve of the acoustic structure (e.g., acoustic structure 230). When frequency response curve 410 has a resonance peak at frequency f0, frequency f0 can be called the resonant frequency (or second resonant frequency) of the acoustic-electric converter. In some embodiments, the resonant frequency of the acoustic-electric converter is related to the structural parameters of the acoustic-electric converter. The structural parameters of the acoustic-electric converter may include the material, size, mass, type (e.g., piezoelectric, capacitive, etc.), and arrangement of the acoustic-electric converter (e.g., acoustic-electric converter 220). At frequency f1 of frequency response curve 420, the acoustic structure resonates with the received sound signal, causing the sound signal to amplify the frequency band containing frequency f1. The resonant frequency f1 can be called the resonant frequency (or first resonant frequency) of the acoustic structure. The resonant frequency of the acoustic structure can be expressed as formula (1):

[0094]

[0095] Where f represents the resonant frequency of the acoustic structure, c0 represents the speed of sound in air, S represents the cross-sectional area of ​​the sound guide tube, l represents the length of the sound guide tube, and V represents the volume of the acoustic cavity.

[0096] According to formula (1), the resonant frequency of an acoustic structure is related to the cross-sectional area of ​​the sound guide tube, the length of the sound guide tube, and the volume of the acoustic cavity. Specifically, the resonant frequency of the acoustic structure is positively correlated with the cross-sectional area of ​​the sound guide tube and negatively correlated with the length of the sound guide tube and / or the volume of the acoustic cavity. The resonant frequency of the acoustic structure can be adjusted by setting the structural parameters of the acoustic structure, such as the shape of the sound guide tube, the size of the sound guide tube, the volume of the acoustic cavity, or a combination thereof. For example, if the length of the sound guide tube and the volume of the acoustic cavity remain unchanged, the resonant frequency of the acoustic structure can be reduced by decreasing the aperture of the sound guide tube, thereby reducing the cross-sectional area of ​​the sound guide tube. Alternatively, if the cross-sectional area and length of the sound guide tube remain unchanged, the resonant frequency of the acoustic structure can be increased by decreasing the volume of the acoustic cavity. Finally, if the cross-sectional area and length of the sound guide tube remain unchanged, the resonant frequency of the acoustic structure can be decreased by increasing the volume of the acoustic cavity.

[0097] In some embodiments, to improve the microphone's response to sound signals in a lower frequency range, the structural parameters of the acoustic structure can be set such that the first resonant frequency f1 is less than the second resonant frequency f0. In some embodiments, to keep the microphone's frequency response flat over a wider frequency range, the structural parameters of the acoustic structure can be set such that the difference between the first resonant frequency f1 and the second resonant frequency f0 is not less than a frequency threshold. The frequency threshold can be determined according to actual needs; for example, the frequency threshold can be set to 5Hz, 10Hz, 100Hz, 1000Hz, etc. In some embodiments, the first resonant frequency f1 can be greater than or equal to the second resonant frequency f0, thereby improving the microphone's frequency response sensitivity in different frequency ranges.

[0098] In some embodiments, after the sound signal is modulated by the acoustic structure, the sound signal within a certain frequency band including the first resonant frequency f1 is amplified, making the overall sensitivity of the microphone at the first frequency f1 greater than the sensitivity of the acoustic-to-electrical converter at the first frequency. This improves the microphone's sensitivity and Q value near the first resonant frequency (for example, the increase in microphone sensitivity at frequency f1 can be achieved using...). Figure 4(ΔV1 represents the input). In some embodiments, by incorporating an acoustic structure in the microphone, the sensitivity of the microphone can be increased by 5dBV-40dBV compared to the sensitivity of the electroacoustic transducer. In some embodiments, by incorporating an acoustic structure in the microphone, the sensitivity of the microphone can be increased by 10dBV-20dBV in different frequency bands. In some embodiments, the increase in microphone sensitivity in different frequency ranges can be different. For example, the higher the frequency, the greater the increase in microphone sensitivity in the corresponding frequency band. In some embodiments, the increase in microphone sensitivity can be represented by the slope change of sensitivity within the frequency range. In some embodiments, the slope change of microphone sensitivity in different frequency ranges can be in the range of 0.0005dBV / Hz-0.005dBV / Hz. In some embodiments, the slope change of microphone sensitivity in different frequency ranges can be in the range of 0.001dBV / Hz-0.003dBV / Hz. In some embodiments, the slope of the microphone's sensitivity varies in different frequency ranges from 0.002 dBV / Hz to 0.004 dBV / Hz.

[0099] In some embodiments, the bandwidth of the frequency response curve of the acoustic structure at the first resonant frequency can be expressed by formula (2):

[0100]

[0101] Where Δf represents the bandwidth of the acoustic structure's frequency response, f represents the resonant frequency of the acoustic structure, and R′ a M′ represents the total acoustic resistance of the sound guide tube (including the acoustic resistance of the sound guide tube and the radiation acoustic resistance). a W represents the total acoustic quality of the sound guide tube (including the sound quality of the sound guide tube and the radiated sound quality). r The angular frequency of the acoustic structure is represented by f, where f represents the resonant frequency of the acoustic structure.

[0102] According to formula (2), given a fixed resonant frequency, the bandwidth of the acoustic structure can be adjusted by adjusting the acoustic resistance of the sound guide tube. In some embodiments, an acoustic resistance structure can be incorporated into the microphone. The acoustic resistance value of the acoustic resistance structure can be adjusted by modifying its aperture, thickness, and open area ratio, thereby adjusting the bandwidth of the acoustic structure. For details regarding the acoustic resistance structure, please refer to [reference needed]. Figures 10-16 And its related descriptions.

[0103] In some embodiments, the acoustic impedance of the sound guide tube can be adjusted by adjusting the inner surface roughness of its sidewall, thereby regulating the bandwidth of the frequency response curve of the acoustic structure. In some embodiments, the inner surface roughness of the sound guide tube's sidewall can be less than or equal to 0.8. In some embodiments, the inner surface roughness of the sound guide tube's sidewall can be less than or equal to 0.4. Taking the 3dB bandwidth of the microphone's frequency response curve as an example, by adjusting the structural parameters of the acoustic structure, the 3dB bandwidth of the microphone's frequency response curve can be 100Hz-1500Hz. In some embodiments, by adjusting the inner surface roughness of the sidewall of the sound guide tube corresponding to different acoustic structures, the increase in the 3dB bandwidth of the microphone at different resonant frequencies can be different. For example, by adjusting the inner surface roughness of the sidewall of the sound guide tube corresponding to different acoustic structures, the higher the resonant frequency of the acoustic structure, the greater the increase in the 3dB bandwidth of the microphone at its corresponding resonant frequency. In some embodiments, the increase in the 3dB bandwidth of the microphone at different resonant frequencies can be represented by the change in the slope of the bandwidth. In some embodiments, the slope of the microphone's 3dB bandwidth over the frequency range may be between 0.01 Hz / Hz and 0.1 Hz / Hz. In some embodiments, the slope of the microphone's 3dB bandwidth over the frequency range may be between 0.05 Hz / Hz and 0.1 Hz / Hz. In some embodiments, the slope of the microphone's 3dB bandwidth over the frequency range may be between 0.02 Hz / Hz and 0.06 Hz / Hz.

[0104] In some embodiments, the amplification factor (also known as gain) of the acoustic structure on the sound pressure of the sound signal can be expressed as formula (3):

[0105]

[0106] Among them, A P denoted as the sound pressure amplification factor, l0 as the length of the sound guide tube, s as the cross-sectional area of ​​the sound guide tube, and V as the volume of the acoustic cavity.

[0107] According to formula (3), the sound pressure amplification factor of the acoustic structure for sound signals is related to the length of the sound guide tube, the cross-sectional area of ​​the sound guide tube, and the volume of the acoustic cavity. Specifically, the sound pressure amplification factor of the acoustic structure for sound signals is positively correlated with the length of the sound guide tube and the volume of the acoustic cavity, and negatively correlated with the cross-sectional area of ​​the sound guide tube.

[0108] According to formula (1), formula (3) can also be transformed into formula (4):

[0109]

[0110] Among them, A PThe sound pressure amplification factor is represented by c0, the speed of sound in air is represented by l, the length of the sound tube is represented by f, the resonant frequency of the acoustic structure is represented by R, and the radius of the acoustic cavity is represented by R.

[0111] As can be seen from formula (4), under the condition that other conditions (e.g., the length of the sound guide tube, the radius of the acoustic cavity, etc.) are constant, the sound pressure amplification factor A of the acoustic structure for the sound signal is... p The sound pressure amplification factor A is related to the resonant frequency f of the acoustic structure. p The sound pressure amplification factor A is negatively correlated with the resonant frequency f of the acoustic structure; the smaller the resonant frequency f, the greater the amplification factor A. p The larger the amplification factor, the lower the amplification factor, and vice versa. In other words, an acoustic structure amplifies sound signals at relatively low resonant frequencies (e.g., mid-to-low frequency ranges). The resonant frequency, bandwidth, amplification factor for specific frequency components of the sound signal, sensitivity increment, Q value, etc., of a microphone can be altered by setting the parameters of the acoustic structure. These parameters can include the shape and size of the sound guide tube, the size of the acoustic cavity, the acoustic resistance of the sound guide tube or cavity, the roughness of the inner surface of the sound guide tube's sidewalls, the thickness of the sound-absorbing material inside the sound guide tube, and combinations thereof.

[0112] Figure 5 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 5 As shown, the microphone 500 may include a housing 510, at least one acoustic-to-electrical transducer 520, and an acoustic structure 530. Figure 5 One or more components of the microphone 500 shown may be the same as or similar to one or more components of the microphone 200. For example, the housing 510, the acoustic-to-electric transducer 520, the aperture 521 of the acoustic-to-electric transducer 520, the acoustic cavity 540, the application-specific integrated circuit 550, etc., in the microphone 500 may be the same as those in the microphone 200. Figure 3 The housing 210, the acoustic-to-electric converter 220, the aperture 221 of the acoustic-to-electric converter 220, the acoustic cavity 240, and the application-specific integrated circuit 250 in the microphone 200 shown are the same as or similar to those in the microphone 200. Unlike the acoustic structure 230 of the microphone 200, the shape and / or position of the sound guide tube 532 in the acoustic structure 530 of the microphone 500 are different.

[0113] like Figure 5As shown, the acoustic structure 530 may include an acoustic cavity 531 and a sound guide tube 532. The acoustic cavity 531 is acoustically connected to the acoustic-to-electric converter 520 through a hole 521. The acoustic cavity 531 is acoustically connected to the external acoustic environment of the microphone 500 through the sound guide tube 532. The first end of the sound guide tube 532 is located on the first sidewall 511 of the housing 510, and the second end of the sound guide tube 532 is located in the acoustic cavity 531. The sidewall 533 of the sound guide tube 532 extends from the first sidewall 511 into the acoustic cavity 531. External sound signals enter the interior of the sound guide tube 532 from the first end of the sound guide tube 532 and are transmitted to the acoustic cavity 531 from the second end of the sound guide tube 532. By extending the second end of the sound guide tube 532 into the acoustic cavity 531, the length of the sound guide tube 532 and the volume of the acoustic cavity 531 can be increased without increasing the size of the microphone 500. According to formula (1), increasing the length of the sound guide tube 532 and the volume of the acoustic cavity 531 can reduce the resonant frequency of the acoustic structure 530, so that the frequency response curve of the microphone 500 has a resonant peak at a relatively low resonant frequency.

[0114] In some embodiments, the resonant frequency of the acoustic structure 530 can be further adjusted by setting the length, shape, etc., of the sound guide 532. This is merely an example. Figure 6 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 6 As shown, the sound guide tube 532 has a straight curved structure. The first end of the sound guide tube 532 is located on the first sidewall 511 of the housing 510, and the second end is located in the acoustic cavity 531. The sidewall 533 of the sound guide tube 532 extends from the first sidewall 511 into the acoustic cavity 531. By setting the sound guide tube 532 to a curved shape, the length of the sound guide tube 532 can be increased without significantly reducing the size of the acoustic cavity 531. This allows for a reduction in the resonant frequency of the acoustic structure 530, improving the sensitivity and Q value of the microphone 500 in the lower frequency range. In some embodiments, the structure of the sound guide tube 532 is not limited to the aforementioned straight structure (e.g., Figure 5 As shown), straight-line curved structure (e.g., Figure 6 (As shown), other types of structures can also be used. For example, to reduce acoustic resistance, an arc-shaped bending structure can be designed. In some embodiments, to adjust the acoustic resistance, the included angle between the two sections of the sound guide tube can be adjusted. For example, the included angle between the centerlines of the two tubes can range from 60° to 150°, or from 60° to 90°, or from 90° to 120°, or from 120° to 150°.

[0115] In some embodiments, the first end of the sound guide tube 532 may be located away from the first sidewall 511 and outside the housing 510, the second end of the sound guide tube 532 may be located inside the acoustic cavity 531, and the sidewall 533 of the sound guide tube 532 may extend from the sidewall 511 of the housing 510 into the acoustic cavity 531. This is merely an example. Figure 7 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 7 As shown, the sound guide tube 532 of the microphone 500 penetrates the first sidewall 511 of the housing 510. The first end of the sound guide tube 532 extends away from the first sidewall 511 towards the outside of the housing 510 and is located outside the housing 510. The second end of the sound guide tube 532 extends away from the first sidewall 511 into the acoustic cavity 531 and is located inside the acoustic cavity 531. External sound signals can enter the sound guide tube 532 from the first end of the sound guide tube 532 and be transmitted to the acoustic cavity 531 from the second end of the sound guide tube 532.

[0116] Figure 8 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 8 As shown, the microphone 800 may include a housing 810, at least one acoustic-to-electrical transducer 820, and an acoustic structure 830. Figure 8 One or more components in the microphone 800 shown can be used with Figure 5 One or more components in the microphone 500 shown are the same as or similar to those in the microphone 800. For example, the housing 810, the acoustic-to-electric transducer 820, the aperture 821 of the acoustic-to-electric transducer 820, the acoustic cavity 840, the application-specific integrated circuit 850, etc., in the microphone 800 may be the same as or similar to those in the microphone 500. The difference between the microphone 800 and the microphone 500 lies in the position and / or shape of the sound guide tube 832 of the acoustic structure 830.

[0117] like Figure 8As shown, the acoustic structure 830 may include an acoustic cavity 831 and a sound guide tube 832. The sound guide tube 832 may include one or more sidewalls for forming the sound guide tube 832, such as sidewall 833 and sidewall 834. In some embodiments, sidewall 833 and sidewall 834 may be an integral part or different parts of the same sidewall of the sound guide tube 832. For example, sidewall 833 and sidewall 834 may be integrally formed. In some embodiments, sidewall 833 and sidewall 834 may be independent structures. In some embodiments, one or more sidewalls of the sound guide tube 832 may form a certain tilt angle with the central axis 835 of the sound guide tube 832. Taking sidewall 833 as an example, the sidewall 833 of the sound guide tube 832 forms an tilt angle α with the central axis 835 of the sound guide tube 832. In some embodiments, such as Figure 8 As shown, assuming the direction of the central axis of the sound guide tube 832 pointing towards the acoustic cavity 831 is the positive direction, when the aperture of the sound guide tube 832 contracts inward along the positive direction of the central axis 835, that is, when the sidewalls 833 and / or 834 of the sound guide tube 832 move closer to the central axis 835 along the positive direction of the central axis 835, the tilt angle α can be any value between 0° and 90°. For example, the tilt angle α can be any value between 0° and 30°. Another example is that the tilt angle α can be any value between 30° and 45°. Yet another example is that the tilt angle α can be any value between 45° and 60°. And yet another example is that the tilt angle α can be any value between 60° and 90°.

[0118] In some embodiments, such as Figure 9 As shown, when the aperture of the sound guide tube 832 expands outward along the positive direction of the central axis 835, that is, when the sidewalls 833 and / or 834 of the sound guide tube 832 extend away from the central axis 835 along the positive direction of the central axis 835, the angle β formed by the sidewalls of the sound guide tube 832 (e.g., sidewalls 833 and / or 834) and the central axis 835 can be any value between 0° and 90°. For example, the angle β can be any value between 0° and 10°. Another example is that the angle β can be any value between 10° and 20°. Yet another example is that the angle β can be any value between 0° and 30°. Yet another example is that the angle β can be any value between 30° and 45°. Yet another example is that the angle β can be any value between 45° and 60°. Yet another example is that the angle β can be any value between 60° and 90°.

[0119] By setting a certain angle between the sidewall of the sound guide tube 832 and the central axis of the sound guide tube 832, the position of the resonant frequency of the microphone 800 can be adjusted without changing the length of the sound guide tube 832 and the outer diameter of the first end of the sound guide tube 832 (e.g., the end located on the first sidewall 811 of the housing 810 or the end located away from the first sidewall 811 and outside the microphone 800). For example, when the aperture of the sound guide tube 832 shrinks inward along the positive direction of the central axis 835, the cross-sectional size of the second end of the sound guide tube 832 (e.g., the end extending into the acoustic cavity 831) can be reduced without changing the length of the sound guide tube 832 and the aperture of the first end of the sound guide tube 832, thereby reducing the resonant frequency of the acoustic structure 830. For example, when the aperture of the sound guide tube 832 expands outward along the positive direction of the central axis 835, the cross-sectional dimensions of the second end of the sound guide tube 832 can be increased without changing the length of the sound guide tube 832 and the aperture of the first end of the sound guide tube 832, thereby increasing the resonant frequency of the acoustic structure 830.

[0120] In some embodiments, when the cross-section of the acoustic cavity 831 (e.g., a cross-section parallel to the XZ plane) is circular, the aperture of the first end of the sound guide tube 832 may not exceed 1.5 times the length of the sound guide tube 832. In some embodiments, the aperture of the first end of the sound guide tube 832 may be in the range of 0.1 mm to 3 mm, and the length of the sound guide tube 832 may be in the range of 1 mm to 4 mm. In some embodiments, the aperture of the first end of the sound guide tube 832 may be in the range of 0.1 mm to 2 mm, and the length of the sound guide tube 832 may be in the range of 1 mm to 3 mm.

[0121] Figure 10 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 10 As shown, the microphone 1000 may include a housing 1010, at least one acoustic-to-electrical transducer 1020, and an acoustic structure 1030. The acoustic structure 1030 may include a sound guide tube 1032 and an acoustic cavity 1031. Figure 10 One or more components in the microphone 1000 shown can be used with Figure 2A One or more components in the microphone 200 shown are identical or similar. For example, the housing 1010, the acoustic-to-electric transducer 1020, the aperture 1021 of the acoustic-to-electric transducer 1020, the acoustic structure 1030, the acoustic cavity 1040, the application-specific integrated circuit 1050, etc., in the microphone 1000 may be the same as those in the microphone 200. Figure 3 The housing 210, the acoustic-electric converter 220, the aperture 221 of the acoustic-electric converter 220, the acoustic structure 230, the acoustic cavity 240, etc. in the microphone 200 shown are the same or similar.

[0122] In some embodiments, the difference between microphone 1000 and microphone 200 is that microphone 1000 may further include an acoustic damping structure 1060. According to formula (2), the acoustic damping structure 1060 can be used to adjust the bandwidth of the acoustic structure 1030. In some embodiments, the acoustic damping structure 1060 may include a diaphragm acoustic damping structure, a mesh acoustic damping structure, a plate acoustic damping structure, or a combination thereof. In some embodiments, the acoustic damping structure 1060 may include a single-layer damping structure, a multi-layer damping structure, or other damping structures. A multi-layer damping structure may include a single multi-layer damping structure or a damping structure composed of multiple single-layer damping structures.

[0123] In some embodiments, the acoustic impedance structure 1060 may be disposed on the outer surface of the first sidewall 1011 away from the housing 1010 of the sidewall 1033 of the sound guide tube 1032, inside the sound guide tube 1032, on the inner surface of the first sidewall 1011, on the outer surface of the first sidewall 1011, in the acoustic cavity 1031, on the inner surface of the second sidewall 1051 for forming the aperture 1021 of the acoustic-electric converter 1020, on the outer surface of the second sidewall 1051, inside the aperture 1021 of the acoustic-electric converter 1020, or a combination thereof.

[0124] like Figure 10 As shown, the acoustic damping structure 1060 can be disposed as a single-layer damping structure on the outer surface of the sidewall 1033 of the sound guide tube 1032, away from the first sidewall 1011. The material, size, thickness, etc., of the acoustic damping structure 1060 can be set according to actual needs. For example, the length of the acoustic damping structure 1060 along the X-axis can be equal to the sum of the lengths of the sound guide tube 1032 and its sidewall 1033. Another example is that the length of the acoustic damping structure 1060 along the X-axis can be equal to or greater than the aperture of the sound guide tube 1032. Yet another example is that the width of the acoustic damping structure 1060 along the Z-axis can be equal to or greater than the width of the sidewall 1033 of the sound guide tube 1032.

[0125] like Figure 11 As shown, the acoustic damping structure 1060 can be disposed on the inner surface of the first sidewall 1011 in the form of a single-layer damping structure. In some embodiments, the acoustic damping structure 1060 can be connected to one or more sidewalls of the housing 1010 (e.g., sidewalls 1011, 1012, 1013, etc. of the housing 1010). The material, size, thickness, etc. of the acoustic damping structure 1060 can be set according to actual needs. For example, the length of the acoustic damping structure 1060 along the X-axis direction can be less than or equal to the length of the sidewall 1011 of the housing 1010 along the X-axis direction. As another example, the width of the acoustic damping structure 1060 along the Z-axis direction can be less than or equal to the width of the sidewall 1011 of the housing 1010 along the Z-axis direction. As yet another example, the size of the acoustic damping structure 1060 can be greater than, equal to, or smaller than the aperture of the sound guide tube 1032.

[0126] like Figure 12 As shown, the acoustic damping structure 1060 can be disposed in the acoustic cavity 1031 in the form of a single-layer damping structure, and may or may not be in contact with the sidewall forming the sound guide 1032. For example, the two ends of the acoustic damping structure 1060 can be connected to the sidewall 1011 and / or sidewall 1013 of the housing 1010, respectively. Figure 13 As shown, the acoustic damping structure 1060 can be disposed as a single-layer damping structure on the outer surface of the second sidewall 1051 of the aperture 1021 used to form the acoustic-electric converter 1020, and can be physically connected to or not connected to the second sidewall 1051. For example, the two ends of the acoustic damping structure 1060 can be connected to the sidewalls 1012 and 1013 of the housing 1010, respectively. Alternatively, the acoustic damping structure 1060 can be physically connected to the second sidewall 1051. In some embodiments, the dimensions of the acoustic damping structure 1060 can be the same as or different from the dimensions of the second sidewall 1051. For example, the length of the acoustic damping structure 1060 along the X-axis can be greater than, equal to, or less than the length of the second sidewall 1051 along the X-axis and the aperture of the aperture 1021. In some embodiments, the dimensions of the acoustic damping structure 1060 can be larger than the dimensions of the aperture 1021 of the acoustic-electric converter 1020.

[0127] like Figure 14 As shown, the acoustic damping structure 1060 can be disposed inside the sound guide tube 1032 in the form of a single-layer damping structure, and it can be wholly or partially connected to the sidewall 1033 of the sound guide hole. In some embodiments, the material, size, thickness, etc. of the acoustic damping structure 1060 can be set according to actual needs. For example, the thickness of the acoustic damping structure 1060 along the Y-axis direction can be greater than, equal to, or less than the length of the sound guide tube 1032 along the Y-axis direction. As another example, the length of the acoustic damping structure 1060 along the X-axis direction can be greater than, equal to, or less than the aperture of the sound guide tube 1032.

[0128] Figure 15 These are schematic diagrams of the microphone structure shown in some embodiments of this specification, such as... Figure 15As shown, the acoustic damping structure 1060 may include a double-layer damping structure, which may include a first acoustic damping structure 1061 and a second acoustic damping structure 1062. The first acoustic damping structure 1061 may be disposed on the outer surface of the first sidewall 1011 of the sidewall 1033 forming the sound guide tube 1032, away from the housing 1010, and may be physically connected to or not connected to the outer surface of the first sidewall 1011. The second acoustic damping structure 1062 may be disposed on the inner surface of the first sidewall 1011, and may be physically connected to or not connected to the inner surface of the first sidewall 1011. In some embodiments, the position, size, material, etc. of the first acoustic damping structure 1061 and the second acoustic damping structure 1062 may be set according to actual needs, and they may be the same or different. For example, the first acoustic resistive structure 1061 and / or the second acoustic resistive structure 1062 can be disposed in the acoustic cavity 1031 (e.g., physically connected to the second sidewall 1051, the first sidewall 1011, the sidewall 1012, the sidewall 1013, etc.). As another example, the first acoustic resistive structure 1061 and / or the second acoustic resistive structure 1062 can be disposed in the aperture 1021 of the acoustic-to-electric converter 1020. As yet another example, the first acoustic resistive structure 1061 and / or the second acoustic resistive structure 1062 can be disposed in the sound guide tube 1032. As yet another example, the first acoustic resistive structure 1061 and / or the second acoustic resistive structure 1062 can be disposed on the outer surface of the sidewall 1033 of the sound guide tube 1032.

[0129] In some embodiments, the acoustic impedance value of the acoustic impedance structure 1060 can be changed by adjusting its parameters. In some embodiments, the parameters of the acoustic impedance structure 1060 may include, but are not limited to, its thickness, pore size, and porosity. In some embodiments, the thickness of the acoustic impedance structure 1060 can be 20 micrometers to 300 micrometers. In some embodiments, the thickness of the acoustic impedance structure 1060 can be 10 micrometers to 400 micrometers. In some embodiments, the pore size of the acoustic impedance structure 1060 can be 20 micrometers to 300 micrometers. In some embodiments, the pore size of the acoustic impedance structure 1060 can be 30 micrometers to 300 micrometers. In some embodiments, the pore size of the acoustic impedance structure 1060 can be 10 micrometers to 400 micrometers. In some embodiments, the porosity of the acoustic impedance structure 1060 can be 10% to 50%. In some embodiments, the porosity of the acoustic impedance structure 1060 can be 30% to 50%. In some embodiments, the porosity of the acoustic impedance structure 1060 can be 20% to 40%. In some embodiments, the porosity of the acoustic impedance structure 1060 can be 25%-45%. In some embodiments, the acoustic impedance value of the acoustic impedance structure 1060 ranges from 1 MKS Rayls to 100 MKS Rayls. In some embodiments, by adjusting the parameters of the acoustic impedance structure 1060 (e.g., pore size, thickness, porosity, etc.), the acoustic impedance value of the acoustic impedance structure 1060 can be made to be 10 MKS Rayls-90 MKS Rayls, 20 MKS Rayls-80 MKS Rayls, 30 MKS Rayls-70 MKS Rayls, 40 MKS Rayls-60 MKS Rayls, or 50 MKS Rayls.

[0130] In some embodiments, by incorporating an acoustic impedance structure in the microphone, the acoustic impedance of the microphone's acoustic structure can be increased, thereby adjusting the microphone's frequency response bandwidth (3dB) and / or Q value. In some embodiments, acoustic impedance structures with different acoustic impedance values ​​may have varying degrees of influence on the microphone's frequency response Q value. Figure 16 These are frequency response curves of exemplary microphones shown in some embodiments of this specification. Figure 16As shown, the horizontal axis represents frequency in Hz, and the vertical axis represents the microphone's frequency response in dB. Curve 1610 represents the frequency response of a microphone without an acoustic impedance structure; curve 1615 represents the frequency response of a microphone with an acoustic impedance of 3 MKS Rayls; curve 1620 represents the frequency response of a microphone with an acoustic impedance of 20 MKS Rayls; curve 1630 represents the frequency response of a microphone with an acoustic impedance of 65 MKS Rayls; curve 1640 represents the frequency response of a microphone with an acoustic impedance of 160 MKS Rayls; and curve 1650 represents the frequency response of a microphone with an acoustic impedance of 4000 MKS Rayls. Figure 16 It is known that as the acoustic impedance value of the acoustic resistor structure increases, the bandwidth of the microphone's frequency response curve increases, while the microphone's frequency response decreases. Therefore, the Q value of the microphone can be adjusted by setting the acoustic impedance value of the acoustic resistor structure. In some embodiments, as the acoustic impedance value of the acoustic resistor structure increases, the Q value of the microphone decreases. Therefore, the acoustic impedance value of the acoustic resistor structure can be selected according to actual needs to obtain the target Q value and target bandwidth of the microphone. For example, the acoustic impedance value of the acoustic resistor structure can be set to no more than 20 MKS Rayls, corresponding to a target bandwidth (3dB) of no less than 300Hz. As another example, the acoustic impedance value of the acoustic resistor structure can be no more than 100 MKS Rayls, corresponding to a target bandwidth (3dB) of no less than 1000Hz.

[0131] Figure 17 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 17 As shown, microphone 1700 may include housing 1710, at least one acoustic-to-electric transducer 1720, acoustic structure 1730, acoustic cavity 1740, and acoustic structure 1770 (also referred to as a second acoustic structure). One or more components in microphone 1700 can be coupled with... Figure 3 One or more corresponding components in the microphone 300 shown are identical or similar. For example, housing 1710, at least one acoustic-to-electrical transducer 1720, acoustic structure 1730, acoustic cavity 1740, application-specific integrated circuit 1750, etc., are similar to... Figure 3The housing 210, at least one acoustic-to-electric transducer 220, acoustic structure 230, acoustic cavity 240, application-specific integrated circuit 250, etc., in the microphone 200 shown are the same or similar. The microphone 1700 differs from the microphone 200 in that the microphone 1700 may further include a second acoustic structure 1770. In some embodiments, the second acoustic structure 1770 may be connected in series with the acoustic structure 1730. The series connection of the second acoustic structure 1770 and the acoustic structure 1730 means that the second acoustic cavity 1771 of the second acoustic structure 1770 can be acoustically connected to the acoustic cavity 1731 of the acoustic structure 1730 through the sound guide tube 1732 of the acoustic structure 1730. In some embodiments, the second acoustic cavity 1771 of the second acoustic structure 1770 is acoustically connected to the outside of the microphone 1700 through the second sound guide tube 1772. In some embodiments, the sound guide tube 1732 may be disposed on the side wall 1711 constituting the acoustic cavity 1731, and the second sound guide tube 1772 may be disposed on the side wall 1712 constituting the second acoustic cavity 1771.

[0132] In some embodiments, the external sound signal picked up by the microphone 1700 can first be conditioned (e.g., filtered) by the second acoustic structure 1770, and then transmitted to the acoustic structure 1730 through the sound guide tube 1732. The acoustic structure 1730 conditioned the sound signal again, and the conditioned sound signal further entered the acoustic cavity 1740 of the microphone 1700 through the hole 1721, thereby generating an electrical signal.

[0133] In some embodiments, the structural parameters of the second acoustic structure 1770 may be the same as or different from those of the acoustic structure 1730. For example, the acoustic structure 1770 may be cylindrical in shape, and the acoustic structure 1730 may also be cylindrical in shape. As another example, the acoustic resistance of the acoustic structure 1770 may be less than that of the acoustic structure 1730. For information on setting the structural parameters of the acoustic structure 1730 and / or the acoustic structure 1770, please refer to [link to relevant documentation]. Figure 2A , Figure 3 as well as Figure 5-15 And related descriptions.

[0134] In some embodiments, the second acoustic structure 1770 may have a resonant frequency (also referred to as a third resonant frequency). The frequency components of the sound signal at the third resonant frequency will resonate, allowing the second acoustic structure 1770 to amplify the frequency components near the third resonant frequency in the sound signal. The acoustic structure 1730 may have a first resonant frequency. The frequency components of the sound signal amplified by the second acoustic structure 1770 at the first resonant frequency will resonate, allowing the acoustic structure 1730 to further amplify the frequency components near the first resonant frequency in the sound signal. Considering that a particular acoustic structure only has a good amplification effect on sound components within a specific frequency range, for ease of understanding, the sound signal amplified by an acoustic structure can be considered as a sub-band sound signal at the corresponding resonant frequency of that acoustic structure. For example, the sound amplified by the second acoustic structure 1770 can be considered as a sub-band sound signal at the third resonant frequency, and the sound signal further amplified by the acoustic structure 1730 will generate another sub-band sound signal at the first resonant frequency. The amplified sound signal is transmitted to the acoustic-to-electric converter 1720, thereby generating a corresponding electrical signal. In this way, acoustic structure 1730 and second acoustic structure 1770 can respectively improve the Q value of microphone 1700 in the frequency bands including the first resonant frequency and the third resonant frequency, thereby improving the sensitivity of microphone 1700. In some embodiments, the increase in sensitivity of microphone 1700 (relative to acoustic transducer) at different resonant frequencies can be the same or different. For example, when the third resonant frequency is greater than the first resonant frequency, the sensitivity of microphone 1700 at the third resonant frequency is greater than the sensitivity of microphone 1700 at the first resonant frequency. In some embodiments, the resonant frequencies of acoustic structure 1770 and / or acoustic structure 1730 can be adjusted by adjusting the structural parameters of acoustic structure 1770 and / or acoustic structure 1730. In some embodiments, the first resonant frequency corresponding to acoustic structure 1730 and the third resonant frequency corresponding to second acoustic structure 1770 can be set according to actual conditions. For example, the first resonant frequency and the third resonant frequency can be less than the second resonant frequency, thereby improving the sensitivity of microphone 1700 in the mid-low frequency band. For example, the absolute value of the difference between the first resonant frequency and the third resonant frequency can be less than a frequency threshold (e.g., 100Hz, 200Hz, 1000Hz, etc.), thereby improving the sensitivity and Q value of the microphone 1700 within a certain frequency range. Alternatively, the first resonant frequency can be greater than the second resonant frequency, and the third resonant frequency can be less than the second resonant frequency, thereby making the frequency response curve of the microphone 1700 flatter and improving its sensitivity over a wider frequency range.

[0135] The description of the microphone 1700 above is for illustrative purposes only and is not intended to limit the scope of this specification. Various changes and modifications can be made by those skilled in the art based on the description herein. In some embodiments, the microphone 1700 may include multiple acoustic structures (e.g., 3, 5, 11, 14, 64, etc.). In some embodiments, the acoustic structures in the microphone may be connected in series, parallel, or a combination thereof. In some embodiments, the magnitudes of the first resonant frequency, the second resonant frequency, and the third resonant frequency can be adjusted according to actual needs. For example, the first resonant frequency and / or the third resonant frequency may be less than, equal to, or greater than the second resonant frequency. As another example, the first resonant frequency may be less than, equal to, or greater than the third resonant frequency. These changes and modifications are still within the scope of protection of this specification.

[0136] Figure 18 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 18 As shown, the microphone 1800 may include a housing 1810, at least one acoustic-to-electrical transducer 1820, an acoustic structure 1830, a second acoustic structure 1870, and a third acoustic structure 1880.

[0137] In some embodiments, housing 1810 may be used to accommodate one or more components of microphone 1800 (e.g., at least a portion of acoustic transducer 1820, acoustic structure 1830, second acoustic structure 1870, and / or third acoustic structure 1880). One or more components of microphone 1800 may be connected to... Figure 17 One or more components in the microphone 1700 shown are identical or similar. For example, the housing 1810, at least one acoustic-to-electrical transducer 1820, acoustic structure 1830, acoustic cavity 1840, application-specific integrated circuit 1850, etc., are similar. Figure 17 The housing 1710, at least one acoustic-to-electrical transducer 1720, acoustic structure 1730, acoustic cavity 1740, and application-specific integrated circuit 1750 in the microphone 1700 shown are the same as or similar. The microphone 1800 differs from the microphone 1700 in that the number of acoustic structures included in the microphone 1800 and the connection method therebetter may be different from those in the microphone 1700.

[0138] In some embodiments, the housing 1810 may be a hollow structure that forms one or more acoustic cavities, such as acoustic cavity 1840, acoustic structure 1830, second acoustic structure 1870, and third acoustic structure 1880. In some embodiments, an acoustic-to-electric transducer 1820 may be disposed in the acoustic cavity 1840. In some embodiments, the acoustic-to-electric transducer 1820 may include a hole 1821. The third acoustic structure 1880 may be acoustically connected to the acoustic-to-electric transducer 1820 through the hole 1821. In some embodiments, the acoustic structure 1830 may include a sound guide tube 1831 and an acoustic cavity 1832, the second acoustic structure 1870 may include a second sound guide tube 1871 and a second acoustic cavity 1872, and the third acoustic structure 1880 may include a third sound guide tube 1881, a fourth sound guide tube 1882, and a third acoustic cavity 1883. Acoustic cavity 1832 is acoustically connected to third acoustic cavity 1883 via third sound guide tube 1881. Acoustic cavity 1832 is acoustically connected to the external acoustic interface of acoustic microphone 1800 via sound guide tube 1831. Second acoustic cavity 1872 is acoustically connected to third acoustic cavity 1883 via fourth sound guide tube 1882. Second acoustic cavity 1872 is acoustically connected to the external acoustic interface of acoustic microphone 1800 via second sound guide tube 1871. Third acoustic cavity 1883 is acoustically connected to acoustic converter 1820 via aperture 1821 of acoustic converter 1820.

[0139] In some embodiments, the acoustic structure 1830 has a first resonant frequency, the acoustic-to-electric transducer 1820 has a second resonant frequency, the second acoustic structure 1870 has a third resonant frequency, and the third acoustic structure 1880 has a fourth resonant frequency. In some embodiments, the first, third, and / or fourth resonant frequencies may be the same as or different from the second resonant frequency. For example, the first resonant frequency may be greater than 10000Hz, the second resonant frequency may be in the range of 500-700Hz, the third resonant frequency may be in the range of 700Hz-1000Hz, and the fourth resonant frequency may be in the range of 1000Hz-1300Hz, thereby improving the sensitivity of the microphone 1800 over a wider frequency band. Alternatively, the first, third, and fourth resonant frequencies may be less than the second resonant frequency, thereby improving the frequency response and sensitivity of the microphone 1800 in the mid-to-low frequency range. For example, some of the first, third, and fourth resonant frequencies can be lower than the second resonant frequency, while others can be higher than the second resonant frequency, thereby improving the sensitivity of the microphone 1800 over a wider frequency band. Furthermore, the first, third, and fourth resonant frequencies can lie within a specific frequency range, thereby improving the sensitivity and Q value of the microphone 1800 within that specific range.

[0140] When sound signal processing is performed using microphone 1800, the sound signal can enter the acoustic cavity 1832 of acoustic structure 1830 through sound guide tube 1831 and / or enter the second acoustic cavity 1872 of second acoustic structure 1870 through second sound guide tube 1871. Acoustic structure 1830 can adjust the sound signal to generate a first sub-band sound signal with a first resonant peak at a first resonant frequency. Similarly, second acoustic structure 1870 can process the sound signal to generate a second sub-band sound signal with a second resonant peak at a third resonant frequency. The first and / or second sub-band sound signals generated after adjustment by acoustic structure 1830 and / or second acoustic structure 1870 can enter the third acoustic cavity 1883 through third sound guide tube 1881 and fourth sound guide tube 1882, respectively. Third acoustic structure 1880 can further adjust the first and second sub-band sound signals to generate a third sub-band sound signal with a third resonant peak at a fourth resonant frequency. The first sub-band acoustic signal, the second sub-band acoustic signal, and the third sub-band acoustic signal generated by the acoustic structure 1830, the second acoustic structure 1870, and the third acoustic structure 1880 can be transmitted to the acoustic-to-electrical converter 1820 through the aperture 1821. The acoustic-to-electrical converter 1820 can generate electrical signals based on the first sub-band acoustic signal, the second sub-band acoustic signal, and the third sub-band acoustic signal.

[0141] It should be noted that the acoustic structure included in the microphone 1800 is not limited to... Figure 18 The acoustic structures 1830, 1870, and 1880 shown, as well as the microphone 1800, can be configured in terms of the number of acoustic structures, their structural parameters, quantity, and connection method, according to actual needs (e.g., target resonant frequency, target sensitivity, number of sub-band electrical signals, etc.). This is only an example. Figure 19 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 19 As shown, the microphone 1900 may include a housing 1910, an acoustic-to-electric transducer 1920, an acoustic cavity 1940, acoustic structures 1901, 1902, 1903, 1904, 1905, 1906, and 1907. The acoustic-to-electric transducer 1920 may be disposed in the acoustic cavity 1940. The acoustic-to-electric transducer 1920 may include a port 1921. The acoustic structure 1907 may include an acoustic cavity 1973 and six sound guide tubes respectively communicating with acoustic structures 1901, 1902, 1903, 1904, 1905, and 1906. The microphone 1900 assembly and the sound signal processing process are related to... Figure 18 The microphone in the 1800 is similar, so I will not go into details here.

[0142] Figure 20 This is a schematic diagram of an exemplary microphone according to some embodiments of this specification. For example... Figure 20As shown, the microphone 2000 may include a housing 2010, an acoustic cavity 2040, an acoustic-to-electric transducer 2020, and an acoustic structure 2030. In some embodiments, the acoustic-to-electric transducer 2020 may be disposed in the acoustic cavity 2040. In some embodiments, the acoustic-to-electric transducer 2020 may include multiple acoustic-to-electric transducers, such as acoustic-to-electric transducer 2021, a second acoustic-to-electric transducer 2022, a third acoustic-to-electric transducer 2023, a fourth acoustic-to-electric transducer 2024, a fifth acoustic-to-electric transducer 2025, and a sixth acoustic-to-electric transducer 2026. In some embodiments, the acoustic structure 2030 may include multiple acoustic structures, such as acoustic structure 2031, a second acoustic structure 2032, a third acoustic structure 2033, a fourth acoustic structure 2034, a fifth acoustic structure 2035, and a sixth acoustic structure 2036. In some embodiments, each acoustic structure in the microphone 2000 is correspondingly configured with a sound-to-electric converter. For example, acoustic structure 2031 is acoustically connected to sound-to-electric converter 2021 through a hole in sound-to-electric converter 2021; second acoustic structure 2032 is acoustically connected to second sound-to-electric converter 2022 through a hole in second sound-to-electric converter 2022; third acoustic structure 2033 is acoustically connected to third sound-to-electric converter 2023 through a hole in third sound-to-electric converter 2023; fourth acoustic structure 2034 is acoustically connected to fourth sound-to-electric converter 2024 through a hole in fourth sound-to-electric converter 2024; fifth acoustic structure 2035 is acoustically connected to fifth sound-to-electric converter 2025 through a hole in fifth sound-to-electric converter 2025; and sixth acoustic structure 2036 is acoustically connected to sixth sound-to-electric converter 2026 through a hole 2063 in sixth sound-to-electric converter 2026. Taking the sixth acoustic structure 2036 as an example, the sixth acoustic structure 2036 includes a sound guide tube 2061 and an acoustic cavity 2062. The sixth acoustic structure 2036 is acoustically connected to the outside of the microphone 2000 through the sound guide tube 2061 for receiving sound signals. The acoustic cavity 2062 of the sixth acoustic structure 2036 is acoustically connected to the acoustic-to-electric converter 2026 through the aperture 2063 of the acoustic-to-electric converter 2026. In some embodiments, all acoustic structures in the microphone can correspond to one acoustic converter. For example, the sound guide tubes of acoustic structures 2031, 2032, 3033, 4034, 5035, and 6036 can be acoustically connected to the outside of the microphone 2000, and their acoustic cavities can be acoustically connected to the acoustic converters. For example, the microphone 2000 may include multiple acoustic-to-electric converters. Some of the acoustic structures among the acoustic structures 2031, the second acoustic structure 2032, the third acoustic structure 2033, the fourth acoustic structure 2034, the fifth acoustic structure 2035, and the sixth acoustic structure 2036 may be acoustically connected to one of the acoustic-to-electric converters, and other acoustic structures may be acoustically connected to another acoustic-to-electric converter.For example, microphone 2000 may include multiple acoustic-to-electric transducers. The acoustic cavity of acoustic structure 2031 can be acoustically connected to the acoustic cavity of the second acoustic structure 2032 through the sound guide tube of the second acoustic structure 2032. The acoustic cavity of the second acoustic structure 2032 can be acoustically connected to the acoustic cavity of the third acoustic structure 2033 through the sound guide tube of the third acoustic structure 2033. The fourth acoustic structure 2034 can be acoustically connected to the acoustic cavity of the fifth acoustic structure 2035 through the sound guide tube of the fifth acoustic structure 2035. The acoustic cavity of the fifth acoustic structure 2035 can be acoustically connected to the acoustic cavity 2062 of the sixth acoustic structure 2036 through the sound guide tube 2061 of the sixth acoustic structure 2036. The acoustic cavity of the third acoustic structure 2033 and the acoustic cavity 2062 of the sixth acoustic structure 2036 can be acoustically connected to the same or different acoustic-to-electric transducers. Such variations are all protected within the scope of this instruction manual.

[0143] In some embodiments, each acoustic structure in the acoustic structure 2030 can adjust the received sound signal to generate a sub-band acoustic signal. The generated sub-band acoustic signal can be transmitted to an acousto-electric converter acoustically connected to each acoustic structure, which converts the received sub-band acoustic signal into a sub-band electrical signal. In some embodiments, the acoustic structures in the acoustic structure 2030 can have different resonant frequencies. In this case, the acoustic structures in the acoustic structure 2030 can generate sub-band acoustic signals with different resonant frequencies. After conversion by the acousto-electric converter corresponding to the acoustic structure in the acousto-electric converter 2020, sub-band electrical signals with different resonant frequencies can be generated. In some embodiments, the number of acoustic structures 2030 and / or acousto-electric converters 2020 can be set according to actual conditions. For example, the number of acoustic structures 2030 and / or acousto-electric converters 2020 can be set according to the number of sub-band acoustic signals and / or sub-band electrical signals to be generated. As an example only, when there are 6 sub-band electrical signals to be generated, such as... Figure 20As shown, six acoustic structures can be configured, and the microphone 2000 can output six sub-band signals with resonant frequency ranges of 500Hz-700Hz, 1000Hz-1300Hz, 1700Hz-2200Hz, 3000Hz-3800Hz, 4700Hz-5700Hz, and 7000Hz-12000Hz, respectively. Alternatively, the resonant frequency ranges of the six sub-band signals output by the microphone 2000 can be 500Hz-640Hz, 640Hz-780Hz, 780Hz-930Hz, 940Hz-1100Hz, 1100Hz-1300Hz, and 1300Hz-1500Hz, respectively. For example, the resonant frequency ranges of the six sub-charged signals output by the microphone 2000 can be 20Hz-120Hz, 120Hz-210Hz, 210Hz-320Hz, 320Hz-410Hz, 410Hz-500Hz, and 500Hz-640Hz, respectively.

[0144] In some embodiments, by incorporating one or more acoustic structures in the microphone, such as acoustic structures 1730 and 1770 in microphone 1700, acoustic structures 1830, 1870, and 1880 in microphone 1800, and acoustic structures 1901, 1902, 1903, 1904, 1905, and 1906 in microphone 1900, the resonant frequency of the microphone can be increased, thereby improving the microphone's sensitivity over a wider frequency band. Furthermore, by incorporating multiple acoustic structures and / or the connection method of the acoustic-to-electrical transducer, for example... Figure 20 Each acoustic structure in the microphone 2000 shown is configured with a corresponding acoustic-to-electric converter, which can improve the sensitivity of the microphone 2000 over a wider frequency range, and can also divide the sound signal into sub-band signals, thereby reducing the burden of subsequent hardware processing.

[0145] Figure 21 This is a schematic diagram of the frequency response curves of an exemplary microphone according to some embodiments of this specification. Figure 21 As shown, the horizontal axis represents frequency in Hz, and the vertical axis represents the microphone's frequency response in dBV. Taking a microphone comprising 11 acoustic components as an example... Figure 21 The 11 dashed lines represent the frequency response curves of 11 acoustic structures. In some embodiments, the frequency response curves of the 11 acoustic structures can cover the frequency band of 20Hz-20kHz that is audible to the human ear. Figure 21The solid line in the figure represents the microphone's frequency response curve 2110. For ease of understanding, the microphone's frequency response curve 2110 can be seen as the result of fusing the frequency response curves of 11 acoustic structures. In some embodiments, the target frequency response curve of the microphone can be adjusted by adjusting the frequency response curves of one or more acoustic structures. For example, since the fundamental frequency of human voice is mainly concentrated between approximately 100Hz and 300Hz, and most speech information is also concentrated in the mid-to-low frequency band, the number of high-frequency sub-band sound signals can be reduced (i.e., the number of acoustic structures with resonant frequencies in the high-frequency band) without reducing the call quality after processing the sub-band sound signals. For another example, at the intersection of two or more acoustic structure frequency response curves (e.g., two adjacent frequency response curves), the frequency response curve of the fused microphone may produce a dip. This dip can be understood as the difference in frequency response between adjacent peaks and troughs in the fused frequency response curve (e.g., curve 2110). Figure 21 The pitting (ΔdBV shown in the figure) can cause significant fluctuations in the microphone's frequency response, thus affecting the microphone's sensitivity and / or Q value. In some embodiments, the resonant frequency of the acoustic structure can be reduced by adjusting its structural parameters, such as decreasing the cross-sectional area of ​​the sound guide, increasing the length of the sound guide, and increasing the volume of the acoustic cavity. In some embodiments, the bandwidth of the acoustic structure's frequency response curve can be increased by adjusting its structural parameters, such as incorporating an acoustic impedance structure in the microphone, thereby reducing the large pitting generated in the high-frequency range of the fused frequency response curve 2110, and thus improving the microphone's performance. For example, Figure 22 These are frequency response curves of exemplary microphones shown in some embodiments of this specification. Figure 22 As shown, the horizontal axis represents frequency in Hz, and the vertical axis represents the microphone's frequency response in dBV. The dashed lines represent the frequency response curves of the microphone's 11 acoustic components. Figure 21 Compared to the 11 acoustic structures corresponding to the 11 dashed lines in the image, Figure 22 The 11 acoustic structures corresponding to the 11 dashed lines in the diagram can have relatively high acoustic impedance, for example, Figure 22 The 11 dashed lines in the diagram correspond to 11 acoustic structures, including those with relatively rough inner surfaces on the sidewalls of the sound guide tubes, sound-absorbing structures within the sound guide tubes or acoustic cavities, and relatively small-sized sound guide tubes. Figure 21 Compared to the frequency response curve of the acoustic structure in 2110, Figure 22 The response curve 2210 of the acoustic structure shown (especially the response curve at relatively high frequencies) has a relatively wide bandwidth. The frequency response curve of the microphone, formed by fusing the frequency response curves of the 11 acoustic structures, has indentations (e.g., Figure 22 The ΔdBV shown is relatively small, and the frequency response curve 2210 after fusion is flatter.

[0146] The basic concepts have been described above. It is clear that the above disclosure is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, various modifications, improvements, and corrections may be made to this specification by those skilled in the art. Such modifications, improvements, and corrections are suggested in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.

[0147] Furthermore, this specification uses specific terms to describe embodiments thereof. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined.

[0148] Furthermore, those skilled in the art will understand that various aspects of this specification can be described and illustrated by a number of patentable types or situations, including any new and useful combination of processes, machines, products or substances or any new and useful improvements thereof.

[0149] Furthermore, unless expressly stated in the claims, the order of elements and sequences, the use of numbers and letters, or other names in this specification are not intended to limit the order of the processes and methods described herein. Although various examples have been discussed in the foregoing disclosure of some embodiments of the invention that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the spirit and scope of the embodiments described herein. For example, while the system components described above can be implemented using hardware devices, they can also be implemented solely using software solutions, such as installing the described system on an existing server or mobile device.

[0150] Similarly, it should be noted that, in order to simplify the description disclosed herein and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of embodiments in this specification may sometimes combine multiple features into a single embodiment, drawing, or description thereof. However, this method of disclosure does not imply that the subject matter of this specification requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of a single embodiment disclosed above.

[0151] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples by terms such as "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical data used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, the numerical data should take into account specified significant digits and employ general methods of digit reservation. Although the numerical ranges and data used to confirm their breadth of range in some embodiments of this specification are approximate values, in specific embodiments, such numerical values ​​are set as precisely as feasible.

Claims

1. A microphone, comprising: At least one sound-to-electric converter for converting sound signals into electrical signals; An acoustic structure, comprising a sound guide tube and an acoustic cavity, wherein the acoustic cavity is acoustically connected to the acoustic-to-electric converter; A second acoustic structure, connected in series with the first acoustic structure, includes a second sound guide tube and a second acoustic cavity. The second acoustic cavity is connected to the first acoustic cavity via the sound guide tube and is also acoustically connected to the external acoustic environment of the microphone via the second sound guide tube. The acoustic structure has a first resonant frequency, the acoustic-electric converter has a second resonant frequency, the second acoustic structure has a third resonant frequency, the absolute value of the difference between the first resonant frequency and the second resonant frequency is not less than 100Hz, and the third resonant frequency is different from the first resonant frequency.

2. The microphone according to claim 1, characterized in that, The sensitivity of the microphone's response at the first resonant frequency is greater than the sensitivity of the at least one acoustic-electric transducer's response at the first resonant frequency.

3. The microphone according to claim 1, characterized in that, The first resonant frequency is related to the structural parameters of the acoustic structure, which include one or more of the following: the shape of the sound guide tube, the size of the sound guide tube, the size of the acoustic cavity, the acoustic resistance of the sound guide tube or the acoustic cavity, and the roughness of the inner surface of the sidewall forming the sound guide tube.

4. The microphone according to claim 1, further comprising a housing, characterized in that, The at least one acoustic-to-electric transducer and the acoustic cavity are located within the housing, the housing including a first sidewall for forming the acoustic cavity.

5. The microphone according to claim 4, characterized in that, The first end of the sound guide tube is located on the first side wall, and the second end of the sound guide tube is away from the first side wall and located outside the housing.

6. The microphone according to claim 4, characterized in that, The first end of the sound guide tube is located on the first side wall, and the second end of the sound guide tube is away from the first side wall and extends into the acoustic cavity.

7. The microphone according to claim 4, characterized in that, The first end of the sound guide tube is away from the first sidewall and located outside the housing, and the second end of the sound guide tube extends into the acoustic cavity.

8. The microphone according to claim 1, characterized in that, The sidewall of the sound guide tube forms an inclined angle with the central axis of the sound guide tube, and the angle of the inclined angle is in the range of 0° to 20°.

9. The microphone according to claim 4, characterized in that, The acoustic tube or the acoustic cavity is provided with an acoustic impedance structure, which is used to adjust the bandwidth of the acoustic structure.

10. The microphone according to claim 9, characterized in that, The acoustic impedance value of the acoustic impedance structure ranges from 1 MKS Rayls to 100 MKS Rayls.

11. The microphone according to claim 9, characterized in that, The acoustic impedance structure is a single-layer damping structure, and the acoustic impedance structure includes a membrane acoustic impedance structure, a mesh acoustic impedance structure, a plate acoustic impedance structure, or a combination thereof. The thickness of the acoustic resistive structure is 20 micrometers to 300 micrometers, the pore size of the acoustic resistive structure is 20 micrometers to 300 micrometers, and / or the porosity of the acoustic resistive structure is 30% to 50%.

12. The microphone according to claim 9, characterized in that, The acoustic impedance structure is disposed in one or more of the following locations: the outer surface of the sidewall forming the sound guide tube away from the first sidewall, the interior of the sound guide tube, the inner surface of the first sidewall, the acoustic cavity, the inner surface of the second sidewall for forming the aperture of the acoustic-electric converter, the outer surface of the second sidewall, and the interior of the aperture of the acoustic-electric converter.

13. The microphone according to claim 1, characterized in that, The diameter of the sound guide tube is no greater than twice the length of the sound guide tube.

14. The microphone according to claim 13, characterized in that, The diameter of the sound guide tube is 0.1 mm to 10 mm, and the length of the sound guide tube is 1 mm to 8 mm.

15. The microphone according to claim 1, characterized in that, The acoustic cavity has a thickness direction along the central axis of the sound guide tube, and the equivalent inner diameter of the acoustic cavity is not less than the thickness of the acoustic cavity.

16. The microphone according to claim 1, characterized in that, The acoustic cavity has a thickness direction along the central axis of the sound guide tube, the equivalent inner diameter of the acoustic cavity is 1 mm to 20 mm, and the thickness of the acoustic cavity is 1 mm to 20 mm.

17. The microphone according to claim 1, characterized in that, When the third resonant frequency is greater than the first resonant frequency, the difference between the sensitivity of the microphone at the third resonant frequency and the sensitivity of the acoustic-electric converter at the third resonant frequency is greater than the difference between the sensitivity of the microphone at the first resonant frequency and the sensitivity of the acoustic-electric converter at the first resonant frequency.

18. The microphone according to claim 1, characterized in that, The at least one acoustic-electric transducer further includes a second acoustic-electric transducer, the second acoustic cavity being acoustically connected to the second acoustic-electric transducer.

19. The microphone according to claim 1, characterized in that, This includes electret microphones or silicon microphones.

20. A microphone, comprising: At least one sound-to-electric converter for converting sound signals into electrical signals; The system comprises a first acoustic structure, a second acoustic structure, and a third acoustic structure. The first acoustic structure includes a first sound guide tube and a first acoustic cavity. The second acoustic structure includes a second sound guide tube and a second acoustic cavity. The third acoustic structure includes a third sound guide tube, a fourth sound guide tube, and a third acoustic cavity. The third acoustic cavity is acoustically connected to the electroacoustic transducer. The first sound guide tube is acoustically connected to the external acoustic environment of the microphone. The second acoustic cavity is acoustically connected to the external acoustic environment of the microphone through the second sound guide tube. The first acoustic structure and the third acoustic structure are connected in series. The first acoustic cavity is acoustically connected to the third acoustic cavity through the third sound guide tube. The second acoustic structure and the third acoustic structure are connected in series. The second acoustic cavity is acoustically connected to the third acoustic cavity through the fourth sound guide tube. The first acoustic structure has a first resonant frequency, the acoustic-electric converter has a second resonant frequency, the second acoustic structure has a third resonant frequency, and the third acoustic structure has a fourth resonant frequency, wherein the absolute value of the difference between the first resonant frequency and the second resonant frequency is not less than 100Hz, the first resonant frequency is different from the third resonant frequency, and the fourth resonant frequency is different from both the third and first resonant frequencies.

21. The microphone according to claim 20, characterized in that, The range of the first or third resonant frequency is 100Hz-15000Hz.

22. The microphone according to claim 20, characterized in that, The first resonant frequency is related to the structural parameters of the first acoustic structure, and the third resonant frequency is related to the structural parameters of the second acoustic structure.

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