RU2792082C1 - Microphones - Google Patents

Abstract

FIELD: acoustics.

SUBSTANCE: microphone consisting of a transducer configured to convert an audio signal into an electrical signal; and an acoustic structure including a guiding sound channel and an acoustic cavity, wherein the acoustic cavity is acoustically connected to at least one above-mentioned acoustoelectric transducer and is acoustically connected to the external environment of the microphone through the guiding sound channel, the acoustic structure having a first resonant frequency by at least one above-mentioned acoustoelectric transducer has a second resonant frequency and the absolute value of the difference between the first resonant frequency and the second resonant frequency is not less than 100 Hz.

EFFECT: increase in the quality factor and sensitivity of the microphone.

11 cl, 22 dwg

Description

The field of technology to which the invention belongs

The present invention generally relates to the field of acoustic devices and, in particular, to microphones.

State of the art

Filtering and frequency separation technologies are widely used in signal processing. As the basis for speech recognition, noise reduction, signal enhancement and other signal processing technologies, filtering and frequency separation technologies are widely used in electroacoustics, communications, image coding, echo cancellation, radar target recognition and other fields. Conventional filtering or frequency separation technology is a technology using hardware or software. Technology using hardware to filter or separate signals is highly influenced by the characteristics of electronic components, and the hardware is relatively complex. Technology using software algorithms for signal filtering or frequency separation is computationally complex, time consuming and requires large computational resources. In addition, conventional signal filtering or frequency separation technology can be affected by the sampling rate, which is likely to create problems such as signal distortion, noise addition, etc.

Therefore, it is necessary to provide a more efficient signal frequency splitter and a method for simplifying the structure of the acoustic device and improving the quality factor (Q value) and the sensitivity of the acoustic device.

Disclosure of the essence of the invention

One embodiment of the present invention provides a microphone. The microphone contains at least one acoustoelectric transducer and an acoustic structure. At least one acoustoelectric transducer is configured to convert an audio signal into an electrical signal. The acoustic structure may comprise a sound guide channel and an acoustic cavity, wherein the acoustic cavity is acoustically connected to said at least one acoustoelectric transducer and is acoustically connected to the external environment of the microphone through the sound guide channel. The acoustic structure has a first resonant frequency, at least one acoustoelectric transducer has a second resonant frequency, and the absolute value of the difference between the first resonant frequency and the second resonant frequency is at least 100 Hz.

In some embodiments, the response sensitivity of the microphone at the first resonant frequency is greater than the response sensitivity of the at least one acoustoelectric transducer at the first resonant frequency.

In some embodiments, the first resonant frequency is dependent on one or more acoustic design parameters, and the one or more acoustic design parameters comprise at least one of sound guide channel shape, sound guide channel size, acoustic cavity size, acoustic impedance. guiding sound channel or acoustic cavity, or the roughness of the inner surface of the side wall that forms the guiding sound channel.

In some embodiments, at least one acoustoelectric transducer and an acoustic cavity are located in the housing, and the housing includes a first side wall for forming an acoustic cavity.

In some embodiments, the implementation of the first end of the guide sound channel is located on the first side wall, and the second end of the guide sound channel is located at a distance from the first side wall and is located outside the housing.

In some embodiments, the first end of the sound guide channel is located on the first side wall, and the second end of the sound guide channel is located at a distance from the first side wall and extends into the acoustic cavity.

In some embodiments, the implementation of the first end of the guide sound channel is at a distance from the first side wall and is located outside the housing, and the second end of the guide sound channel passes into the acoustic cavity.

In some embodiments, the implementation of the side wall of the guide sound channel forms an angle of inclination with the Central axis of the guide sound channel and the value of the angle of inclination is in the range from 0° to 20°.

In some embodiments, an acoustic impedance component is located in the sound guide or acoustic cavity, and the acoustic impedance component is configured to adjust the bandwidth of the acoustic design.

In some embodiments, the acoustic impedance value of the acoustic impedance component is in the range of 1 Pa‧s/m to 100 Pa‧s/m.

In some embodiments, the thickness of the acoustically resistive component is in the range of 20 µm to 300 µm, the aperture size of the acoustically resistive component is in the range of 20 µm to 300 µm, and/or the porosity of the acoustically resistive component is in the range of 30% to 50 %.

In some embodiments, the acoustic impedance component is located at one or more locations, including: on the outer surface of the side wall forming the sound guide duct and remote from the first side wall, inside the sound guide duct, on the inner surface of the first side wall, inside the acoustic cavity, on the inner surface of the second side wall, forming the hole of at least one acoustoelectric transducer, on the outer surface of the second side wall, inside the hole of at least one acoustoelectric transducer.

In some embodiments, the implementation of the aperture size of the audio guide channel does not exceed twice the length of the audio guide channel.

In some embodiments, the sound guide aperture size is in the range of 0.1 mm to 10 mm and the sound guide channel length is in the range of 1 mm to 8 mm.

In some embodiments, the implementation of the roughness of the inner surface of the side wall, forming the guide sound channel, does not exceed 0.8.

In some embodiments, the internal diameter of the acoustic cavity is not less than the thickness of the acoustic cavity.

In some embodiments, the inner diameter of the acoustic cavity is in the range of 1 mm to 20 mm and the thickness of the acoustic cavity is in the range of 1 mm to 20 mm.

In some embodiments, the microphone further comprises a second acoustic structure. The second acoustic structure contains a second guiding sound channel and a second acoustic cavity. The second acoustic cavity is acoustically connected to the external environment of the microphone through the second sound guide channel. The second acoustic structure has a third resonant frequency different from the first resonant frequency.

In some embodiments, when the third resonant frequency is higher than the first resonant frequency, the difference between the response sensitivity of the microphone at the third resonant frequency and the response sensitivity of at least one acoustoelectric transducer at the third resonant frequency is greater than the difference between the response sensitivity of the microphone at the first resonant frequency and response sensitivity of at least one acoustoelectric transducer at the first resonant frequency.

In some embodiments, the second acoustic cavity is acoustically coupled to the acoustic cavity via a sound guide channel.

In some embodiments, the implementation of the microphone contains a third acoustic structure. The third acoustic structure contains a third guiding sound channel, a fourth guiding sound channel and a third acoustic cavity. The acoustic cavity is acoustically connected to the third acoustic cavity through the third sound guide channel. The second acoustic cavity is acoustically connected to the external environment of the microphone through the second sound guide channel and is acoustically connected to the third acoustic cavity through the fourth sound guide channel. The third acoustic cavity is acoustically connected to at least one acoustoelectric transducer. The third acoustic structure has a fourth resonant frequency different from the third resonant frequency and from the first resonant frequency.

In some embodiments, at least one acoustoelectric transducer comprises a second acoustoelectric transducer, the second acoustic cavity being acoustically coupled to the second acoustoelectric transducer.

In some embodiments, the microphone comprises an electret microphone or a silicon microphone.

In some embodiments, the microphone comprises at least one acoustic-electric transducer, a first acoustic structure, and a second acoustic structure. At least one acoustoelectric transducer is configured to convert an audio signal into an electrical signal. The first acoustic structure contains the first guiding sound channel and the first acoustic cavity, the second acoustic structure contains the second guiding sound channel and the second acoustic cavity. The first sound guide channel is acoustically connected to the external environment of the microphone, and the first acoustic cavity is connected to the second acoustic cavity through the second sound guide channel. The second acoustic cavity is acoustically connected to at least one acoustoelectric transducer. The first acoustic structure has a first resonant frequency, the second acoustic structure has a second resonant frequency, and the first resonant frequency and the second resonant frequency are different.

In some embodiments, the first resonant frequency or the second resonant frequency is in the range of 100 Hz - 15,000 Hz.

In some embodiments, the first resonant frequency is associated with one or more design parameters of the first acoustic structure and the second resonant frequency is associated with one or more design parameters of the second acoustic structure.

Additional features will be set forth in part in the following description, and will become apparent to those skilled in the art upon examination of the following contents and drawings, or may become intelligible based on actual production or operation. Features of the present invention can be implemented and obtained in practice or by using various approaches, methods, tools and combinations set forth in the following detailed descriptions of embodiments.

Brief description of the drawings

The present invention is further described based on exemplary embodiments. These exemplary embodiments are described in detail with reference to the drawings. These embodiments are not intended to limit exemplary embodiments in which like reference numerals represent like structures throughout the various views of the drawings, and in which:

Fig. 1 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 2A is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 2B is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 3 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 4 is a graph of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 5 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 6 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 7 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 8 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 9 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 10 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 11 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 12 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 13 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 14 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 15 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 16 is a plot of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 17 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 18 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 19 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 20 is an exemplary microphone in accordance with some embodiments of the present invention;

Fig. 21 is a graph of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention; And

Fig. 22 is a graph of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention.

Detailed description

To illustrate the technical solutions associated with the embodiments of the present invention, the following is a brief explanation of the drawings referred to in the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present invention. Those skilled in the art can apply the present invention to other similar scenarios in accordance with these drawings without further creative effort. It should be understood that the exemplary embodiments are presented merely for the better understanding and application of the present invention by those skilled in the art and are not intended to limit the protection scope of the present invention. Unless the context clearly implies otherwise, or the context indicates otherwise, the same reference numeral in the drawings refers to the same construction or operation.

It should be understood that the terms "system", "device", "unit" and/or "module", "component", "element" as used herein are a means to distinguish between different components, elements, parts, sections or assemblies of different levels in ascending order. However, terms may be replaced by other expressions if they achieve the same purpose.

Various terms are used to describe the spatial and functional relationships between elements (eg, between components), including but not limited to "connection", "attachment", "mate" and "connection". Unless a relationship is explicitly described as "direct" when the present disclosure describes a relationship between a first and a second element, and where the relationship comprises a direct relationship between the first and second elements with no other intermediate elements, then there is an indirect relationship (spatial or functional) between the first and second element through one or more intermediate elements. In contrast, when an element is referred to as connecting, attaching, mating, or connecting directly to other elements, no intermediate elements exist. In addition, spatial and functional relationships between elements can be implemented 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, and the like. or any combination of them. Other words used to describe relationships between elements should be interpreted in a similar way (eg "between", "adjacent" versus "directly adjacent", etc.).

It should be understood that the terms "first", "second", "third", etc., as used herein, may be used to describe various elements. They are only used to distinguish one element from another and are not intended to limit elements. For example, the first element may also be referred to as the second element, and similarly, the second element may also be referred to as the first element.

As used in the disclosure and in the appended claims, singular forms include plural forms unless the content clearly indicates otherwise. In general, the terms "comprise", "comprises" and/or "comprising", "comprise", "includes" and/or "comprising" simply suggest the inclusion of steps and elements that have been clearly identified, and these steps and items are not an exclusive list. The methods or devices may also contain other steps or elements. The term "based" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment". Appropriate definitions of other terms will be given below in the description. Hereinafter, without loss of generality, the description of "microphone" will be used in describing the technology associated with filtering/frequency separation in the present disclosure. This description is only a form of pending application for those skilled in the art, "microphone" may also be replaced by other similar words such as "hydrophone", "transducer", "optoacoustic modulator" or "acoustoelectric transducer device", etc. Those skilled in the art, after understanding the basic principle of a microphone device, can make various modifications and changes in form and detail in a particular microphone method and steps without departing from this principle. However, such corrections and changes remain within the protection scope of the present invention.

The present invention is a microphone. The microphone may include at least one acoustoelectric transducer and an acoustic structure. At least one acoustoelectric transducer may be used to convert the audio signal into an electrical signal. The acoustic structure includes a sound guide channel and an acoustic cavity. The acoustic cavity is acoustically connected to the acoustoelectric transducer and is acoustically connected to the external environment of the microphone through the directing sound channel. The sound guide channel and the acoustic cavity of the acoustic structure can form a filter with a function of adjusting the frequency components of the sound. The circuit exploits the design characteristics of the acoustic design itself to filter the audio signal and/or perform an audio subbanding operation that does not require multiple complex circuits to achieve filtering, thus reducing circuit design difficulties. The filtering properties of an acoustic structure are determined by the physical properties of its structure, and the filtering process occurs in real time.

In some embodiments, the implementation of the acoustic design can "amplify" the sound at its respective resonant frequency. The resonant frequency of the acoustic structure may be controlled by changing one or more design parameters of the acoustic structure. One or more acoustic design parameters may include the shape of the sound guide channel, the size of the sound guide channel, the size of the acoustic cavity, the acoustic impedance of the sound guide channel or acoustic cavity, the roughness of the inner surface of the side wall of the sound guide channel, the thickness of the sound absorbing material in the sound guide channel, etc. .P. or a combination of the above.

In some embodiments, by arranging a plurality of acoustic structures with different resonant frequencies in parallel, in series, or in combination, the frequency components corresponding to the different resonant frequencies in the audio signal can be appropriately filtered so that subbanding of the audio signal frequencies can be realized. In this case, the frequency response of the microphone may be considered as a high signal-to-noise ratio frequency response formed by combining the frequency responses of different acoustic designs, with the corresponding frequency response plot being made flatter (e.g., frequency response plot 2210 shown in FIG. 22) . On the one hand, the microphone provided by the embodiments of the present invention can perform a subband frequency division operation for a wideband signal by its own design without using hardware circuits (for example, filter circuits) or software algorithms, thus avoiding problems such as complex hardware circuit design, large computational resources occupied by software algorithms, signal distortion and noise addition, thus reducing the complexity and cost of manufacturing a microphone. On the other hand, the microphone provided by the embodiments of the present invention may have a flatter frequency response with a high signal-to-noise ratio, thereby improving the signal quality of the microphone. In addition, by arranging different acoustic structures operating in different frequency ranges in the microphone system, resonant peaks can be added that improve the sensitivity of the microphone near the resonant peaks, thus increasing the sensitivity of the microphone over the entire wide frequency band.

In FIG. 1 depicts an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 1, the microphone 100 may include an acoustic structure 110, at least one acoustoelectric transducer 120, a sampler 130, and a signal processor 140,

In some embodiments, microphone 100 may include any audio signal processing device (eg, microphone, hydrophone, optoacoustic modulator, etc., or other acoustoelectric transducer devices) that converts an audio signal into an electrical signal. In some embodiments, in accordance with the principle of conversion, the microphone 100 may include a moving coil microphone, a ribbon microphone, a condenser microphone, a piezoelectric microphone, an electret microphone, an electromagnetic microphone, a carbon microphone, and the like. or any combination of them. In some embodiments, in accordance with the sound collection method, the microphone 100 may include a bone conduction microphone, an air conduction microphone, and the like. or their combination. In some embodiments, according to the manufacturing process, the microphone 100 may include an electret microphone, a silicon microphone, and the like. In some embodiments, the microphone 100 may be installed in a device with a sound sensor function, such as a mobile device (e.g., cell phone, voice recorder, etc.), tablet, laptop computer, vehicle-mounted device, monitoring device, medical device. , sports equipment, toy, wearable device (such as earpiece, helmet, goggles, necklace, etc.), etc.

The acoustic structure 110 may transmit an external audio signal to at least one acoustoelectric transducer 120. As the audio signal passes through the acoustic structure 110, the acoustic structure 110 may make some adjustments to the audio signal (e.g., filtering, changing the audio signal bandwidth, amplifying the audio signal with a certain frequency, etc.). In some embodiments, acoustic structure 110 may include a sound guide and an acoustic cavity. The acoustic cavity is acoustically coupled to the acoustoelectric transducer 120 to transmit to the acoustoelectric transducer 120 an audio signal adjusted by the acoustic structure 110. The acoustic cavity may be acoustically coupled to the external environment of the microphone 100 via an audio guide channel to receive the audio signal. The audio signal can come from any audio source capable of producing an audio signal. The sound source may be a living organism (eg, a user of microphone 100), an inanimate object (eg, a CD player, TV, stereo system, etc.), and the like. or a combination of them. In some embodiments, the implementation of the audio signal may contain ambient sound.

In some embodiments, the acoustic structure 110 has a first resonant frequency, which indicates that the frequency component of the audio signal at the first resonant frequency can resonate, thereby increasing the loudness of the frequency component transmitted to the acoustoelectric transducer 120. Therefore, the location of the acoustic structure 110 can cause the frequency response to the microphone 100 to form a resonant peak at the first resonant frequency so that the sensitivity of the microphone 100 can be improved in a certain frequency band containing the first resonant frequency. For further description regarding the effect of acoustic design 110 on the frequency response of microphone 100, see FIG. 2A-22 and in their descriptions.

In some embodiments, the implementation of the number of acoustic structures 110 in the microphone 100 may be set in accordance with actual requirements. For example, microphone 100 may include multiple (eg, 2, 3, 5, 6-24, etc.) acoustic structures 110. In some embodiments, multiple acoustic structures 110 in microphone 100 may have different frequency responses. For example, multiple acoustic structures 110 in microphone 100 may have different resonant frequencies or bandwidths. Bandwidth may refer to the frequency range between points that differ by 3 dB on a frequency response graph. In some embodiments, after being processed by multiple acoustic structures 110, the audio signal may have a frequency separated to form a plurality of sub-band audio signals (e.g., sub-band audio signal 1111, sub-band audio signal 1112..., sub-band audio signal 111n) having different frequency ranges. A sub-band audio signal refers to a signal whose bandwidth is smaller than the bandwidth of the original audio signal. The frequency band of the subband audio signal may be in the frequency band of the audio signal. For example, the bandwidth of an audio signal may be 100 Hz - 20,000 Hz, and the acoustic structure 110 may be designed to filter the audio signal to form a sub-band audio signal whose bandwidth range may be 100 Hz - 200 Hz. As another example, for dividing the frequency of an audio signal, eleven acoustic structures 110 may be provided to generate eleven sub-band audio signals whose frequency bands may be 500 Hz - 700 Hz, 700 Hz - 1000 Hz, 1000 Hz - 1300 Hz, 1300 Hz - 1700Hz, 1700Hz - 2200Hz, 2200Hz - 3000Hz, 3000Hz - 3800Hz, 3800Hz - 4700Hz, 4700Hz - 5700Hz, 5700Hz - 7000Hz and 7000Hz - 12000Hz, respectively. As a further example, for dividing the frequencies of an audio signal, sixteen acoustic structures 110 can be provided to form sixteen subband audio signals whose frequency bands can be 500 Hz - 640 Hz, 640 Hz - 780 Hz, 780 Hz - 930 Hz, 940 Hz - 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, respectively. As another further example, for dividing the frequencies of an audio signal, twenty-six acoustic structures 110 can be provided to form twenty-six sub-band audio signals whose frequency bands can be 20 Hz-120 Hz, 120 Hz-210 Hz, 210 Hz-320 Hz , 320Hz - 410Hz, 410Hz - 500Hz, 500Hz - 640Hz, 640Hz - 780Hz, 780Hz - 930Hz, 940Hz - 1100Hz, 1100Hz - 1300Hz, 1300Hz - 1500Hz, 1500 Hz - 1750Hz, 1750Hz - 1900Hz, 1900Hz - 2350Hz, 2350Hz - 2700Hz, 2700Hz - 3200Hz, 3200Hz - 3800Hz, 3800Hz - 4500Hz, 4500Hz - 5500Hz, 5500Hz - 6600Hz, 6600Hz - 7900Hz, 7900Hz - 9600Hz, 9600Hz - 12100Hz and 12100Hz - 16000Hz, respectively. Using an acoustic design for filtering and frequency separation, the audio signal can be filtered and/or frequency separated in real time, thus reducing the noise introduced into the subsequent audio hardware processing and preventing signal distortion.

In some embodiments, multiple acoustic structures 110 in microphone 100 may be arranged in parallel, in series, or a combination thereof. For more information on the placement of multiple acoustic structures, see FIG. 17-20 and their descriptions.

The acoustic structure 110 may be connected to an acoustic-electric transducer 120. The acoustic-electric transducer 120 may be configured to transmit the audio signal adjusted by the acoustic structure 110 to the acoustic-electric transducer 120 for conversion into an electrical signal. In some embodiments, the implementation of the acoustoelectric transducer 120 may include a capacitive acoustoelectric transducer, a piezoelectric acoustoelectric transducer, and the like. or their combination. In some embodiments, vibrations in the audio signal (e.g., air vibrations, solid body vibration, liquid vibrations, magnetically induced vibrations, electrically induced vibrations, etc.) may cause one or more parameters of the acoustoelectric transducer 120 to change (e.g., capacitance, electric charge, acceleration , light intensity, frequency response, etc. or a combination). Changed parameters can be electrically detected and an electrical signal corresponding to the fluctuations can be generated. For example, a piezoelectric acoustoelectric transducer may be an element that converts a measured change in a non-electrical signal (eg, pressure, displacement, etc.) into a change in voltage. For example, a piezoelectric acoustoelectric transducer may include a cantilever beam (or diaphragm). The cantilever can be deformed by the received sound signal, and the inverse piezoelectric effect caused by the deformed cantilever can generate an electrical signal. As another example, a capacitive acoustoelectric transducer may be an element that converts a measured change in a non-electrical signal (eg, displacement, pressure, light intensity, acceleration, etc.) into a change in capacitance. For example, the capacitive acoustoelectric transducer may include a first cantilever beam and a second cantilever beam. The first cantilever beam and the second cantilever beam can be deformed to varying degrees by vibration so that the distance between the first cantilever beam and the second cantilever beam changes. The first cantilever beam and the second cantilever beam can convert a change in distance between them into a change in capacitance, so as to realize the conversion of a vibration signal into an electrical signal. In some embodiments, different acoustoelectric transducers 120 may have the same or different frequency responses. For example, acoustoelectric transducers 120 with different frequency responses may detect the same audio signal, and different acoustoelectric transducers 120 may generate subband electrical signals with different resonant frequencies.

In some embodiments, the number of acoustoelectric transducers 120 may be one or more. For example, the acoustoelectric transducers 120 may include an acoustoelectric transducer 121, an acoustoelectric transducer 122..., an acoustoelectric transducer 12n. In some embodiments, one or more of the acoustoelectric transducers 120 may communicate with the acoustic structure 110 in a variety of ways. For example, multiple acoustic structures 110 in microphone 100 may be connected to the same acoustoelectric transducer 120. As another example, each acoustic structure of multiple acoustic structures 110 may be connected to one acoustoelectric transducer 120,

In some embodiments, one or more acoustoelectric transducers 120 may be used to convert the audio signal transmitted by the acoustic structure 110 into an electrical signal. For example, the acoustoelectric transducer 120 may convert the audio signal filtered by the acoustic structure 110 into a corresponding electrical signal. As another example, multiple acoustoelectric transducers of acoustoelectric transducers 120 may respectively convert the subband audio signals obtained by frequency separation of the multiple acoustic structures 110 into multiple corresponding subband electrical signals. Just by way of example, the acoustoelectric transducer 120 may convert subband audio signal 1111, subband audio signal 1112..., and subband audio signal 111n to subband electrical signal 1211, subband electrical signal 1212..., and subband electrical signal 121n.

Acoustic-electric transducer 120 may transmit the generated generated subband electrical signal (or electrical signal) to sampler 130 . In some embodiments, one or more sub-band electrical signals may be separately transmitted through different parallel media lines. In some embodiments, a plurality of subband electrical signals may also be output in a specific format over a common transmission channel according to the rules of a particular protocol. In some embodiments, a particular protocol rule may include, but is not limited to, one or more of the following: direct transmission, amplitude modulation, frequency modulation, and the like. In some embodiments, the transmission channel may be one or more of the following media, but not limited to: coaxial cable, communication cable, flexible cable, spiral cable, non-metallic braided cable, metal braided cable, multicore cable, twisted pair, ribbon cable, shielded cable, communication cable, double twist cable, parallel twin wire, twisted pair, optical fiber, infrared, electromagnetic wave, acoustic wave, etc. In some embodiments, the specific format may be, 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 transfer protocol may be, 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 Appendix C, AAC-LD, etc.

Sampler 130 may be in communication with ac transducer 120 and configured to receive one or more sub-band electrical signals generated by ac-to-electric transducer 120 and select one or more sub-band electrical signals to generate corresponding digital signals.

In some embodiments, sampler 130 may comprise one or more samplers (eg, sampler 131, sampler 132, ..., and sampler 13n). Each sampler 130 may sample each subband electrical signal. For example, sampler 131 may sample sub-band electrical signal 1211 to generate digital signal 1311. As another example, sampler 132 may sample sub-band electrical signal 1212 to generate digital signal 1312. As another example, sampler 13n may sample sub-band electrical signal 121n to generating a digital signal 131n.

In some embodiments, sampler(s) 130 may sample subband electrical signals using a passband sampling technique. For example, the sampling rate of device 130 may be determined according to the bandwidth (in terms of 3 dB) of the subband electrical signal. In some embodiments, sampler(s) 130 may sample subband electrical signals at a sampling rate not less than twice the highest frequency of the subband electrical signal. In some embodiments, sampling device(s) 130 may sample subband electrical signals at a sampling rate that is no less than twice the highest frequency of the subband electrical signal and no greater than four times the highest frequency of the subband electrical signal. Compared to conventional sampling techniques (e.g., bandpass sampling techniques, low-pass filtering sampling techniques, etc.), using the passband sampling technique, the sampling apparatus 130 can sample a relatively lower sampling rate, thereby reducing , difficulties and cost of the sampling process.

In some embodiments, the sample rate of the sampler 130 may influence the cutoff frequency of the sampler 130 of the sample. In some embodiments, the higher the sampling rate, the higher the cutoff frequency and the larger the bandwidth of the possible sampling. When the signal processor 140 processes the digital signal generated by the sampler 130 with the same number of Fourier transform points, the higher the sampling rate, the lower the corresponding frequency resolution. Therefore, for subband electrical signals located in different frequency bands, sampler 130 may use different sampling rates for sampling. For example, for a subband electrical signal located in a low frequency band (eg, a subband electrical signal whose frequency is below a first frequency threshold), the sampling device 130 may use a lower sampling rate, thus making the sampling cutoff frequency relatively low. As another example, for a sub-band electrical signal located in the mid-to-high frequency range (e.g., a sub-band electrical signal whose frequency is above the second frequency threshold and below the third frequency threshold), the sampling device 130 may use a higher sampling rate, the more thereby making the sample cutoff frequency relatively high. As a further example, the sample cutoff frequency of sampler 130 may be 0 Hz - 500 Hz higher than the frequency at the 3 dB passband point for the subband resonant frequency.

Sampler 130 may transmit the generated one or more digital signals to signal processor 140. The one or more digital signals may be transmitted separately over parallel lines of different media. In some embodiments, one or more digital signals may also share a transmission channel and be transmitted in a specific format that conforms to a specific protocol rule. Additional descriptions of digital signal transmission may refer to the transmission of subband electrical signals.

Signal processor 140 may receive and process data received from other components of microphone 100. For example, signal processor 140 may process digital signals transmitted from sampler 130. In some embodiments, signal processor 140 may individually process each subband electrical signal transmitted from sampler 130 to generate a corresponding digital signal. For example, for various sub-band electrical signals (eg, sub-band electrical signals processed by various acoustic designs, acoustoelectric transducers, etc.), which may have different phases, corresponding frequencies, etc., signal processor 140 may process each sub-band electrical signal. In some embodiments, signal processor 140 may receive multiple subband electrical signals from sampler 130 and process (e.g., combine) the multiple subband electrical signals to form a wideband microphone 100 signal.

In some embodiments, signal processor 140 may further comprise one or more devices such as an equalizer, dynamic range controller, phase processor, and the like. In some embodiments, the equalizer may be configured to boost and/or attenuate the digital signal output from the sampler 130 in accordance with a certain frequency band (eg, the bandwidth corresponding to the digital signal). Digital signal amplification refers to the increase in signal gain; Attenuation of a digital signal refers to a decrease in signal gain. In some embodiments, the dynamic range controller may be configured to compress and/or amplify the digital signal. Compressing and/or amplifying a subband electrical signal refers to decreasing and/or increasing the ratio between the input signal and the output signal of the microphone 100. In some embodiments, the phase processor may be configured to adjust the phase of the digital signal. In some embodiments, signal processor 140 may be located in microphone 100. For example, signal processor 140 may be located in an acoustic cavity formed independently of the housing design of microphone 100. In some embodiments, signal processor 140 may also be located in other electronic devices, such as such as a headset, mobile device, tablet, laptop, etc. or any combination of them. In some embodiments, a mobile device may include, but is not limited to, a cellular phone, smart home device, mobile smart device, and the like. or any combination of them. In some embodiments, the smart home device may include a smart device control device, a smart monitoring device, a smart TV, a smart camera, and the like. or any combination of them. In some embodiments, the mobile smart device may include a smartphone, a personal digital assistant (PDA), a gaming device, a navigation device, a POS device, and the like. or any combination of them.

The above description of microphone 100 is for illustrative purposes only and is not intended to limit the scope of the present invention. Numerous changes and modifications can be made by those skilled in the art based on the principles of the present invention. For example, sampler 130 and signal processor 140 may be integrated into a single component (eg, an application specific integrated circuit (ASIC). However, such changes and modifications do not depart from the scope of the present invention.

In FIG. 2A depicts an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 2A, microphone 200 may include a housing 210, at least one acoustoelectric transducer 220, and an acoustic structure 230.

Housing 210 may be configured to accommodate one or more components of microphone 200 (eg, at least one acoustoelectric transducer 220, at least a section of acoustic structure 230, etc.). In some embodiments, the body 210 may be a regularly shaped structure such as a cuboid, cylinder, prism, truncated cone, or other irregularly shaped structures. In some embodiments, housing 210 is hollow and may define one or more acoustic cavities, such as acoustic cavity 231 and acoustic cavity 240. Acoustic cavity 240 may house an acoustoelectric transducer 220 and an ASIC 250. Acoustic cavity 231 may house , at least a portion of the acoustic structure 230. In some embodiments, the housing 210 may include only one acoustic cavity. For example, in FIG. 2B depicts an exemplary microphone in accordance with some embodiments of the present invention. The housing 210 of the microphone 205 may form the acoustic cavity 240. One or more components of the microphone 205, such as the acoustoelectric transducer 220, the ASIC 250, and at least a portion of the acoustic structure 230 (eg, the acoustic cavity 231), may be located in the acoustic cavities 231. In such cases, the acoustic cavity 240 formed by the housing 210 may be covered by the acoustic cavity 231 of the acoustic structure 230. The acoustic structure 230 may be directly acoustically coupled to the acoustoelectric transducer 220. Direct acoustic coupling between the acoustic structure 230 and the acoustoelectric transducer 220 may be understood as follows way: the acoustoelectric transducer 220 may comprise a "front cavity" and a "rear cavity" and an audio signal in the "front cavity" or in the "rear cavity" may cause a change in one or more parameters of the acoustoelectric transducer 220. In the microphone 200 shown in FIG. 2A, the audio signal travels through the acoustic structure 230 (e.g., through the audio guide 232 and the acoustic cavity 231) and then passes through the aperture 221 of the acoustic-electric transducer 220 to the "back cavity" of the acoustic-electric transducer 220, causing one or more parameters of the acoustic-electric transducer 220 to change. In the microphone 205 shown in FIG. 2B, the acoustic cavity 240 formed by the housing 210 is superimposed on the acoustic cavity 231 of the acoustic structure 230, and the "front cavity" of the acoustoelectric transducer 220 can be considered to be superimposed on 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 acoustoelectric transducer 220. For convenience of description, acoustic cavity 231 and acoustic cavity 240 do not overlap (as shown in FIG. 2A), and at least one acoustoelectric transducer 220 that resides in acoustic cavity 240 can be exemplified in present disclosure. The descriptions may be the same or similar to the case in which acoustic cavity 231 and acoustic cavity 240 coincide.

In some embodiments, the body material 210 may comprise one or more, but not limited to, metals, metal alloys, polymers (e.g., styrene butadiene acrylonitrile copolymer, polyvinyl chloride, polycarbonate, polypropylene, etc.), and the like.

In some embodiments, at least one acoustoelectric transducer 220 may be used to convert an audio signal into an electrical signal. At least one acoustoelectric transducer 220 may include one or more apertures 221. Acoustic structure 230 may communicate with at least one acoustoelectric transducer 220 through one or more apertures 221 of acoustoelectric transducer 220 and transmit an audio signal adjusted by acoustic structure 230 to an acoustoelectric transducer 220. For example, after the external audio signal received by the microphone 200 is adjusted (eg, filtered, subbanded, amplified, etc.) by the acoustic structure 230, the audio signal can be introduced into the cavity (if any) of the acoustoelectric transducer 220 through opening 221. Acoustic-electric transducer 220 can sense an audio signal and convert it into an electrical signal.

In some embodiments, the acoustic structure 230 may include an acoustic cavity 231 and a sound guide 232. The acoustic structure 230 may communicate the microphone 200 with the outside environment through the sound guide 232. In some embodiments, the enclosure 210 may include a plurality of side walls to form a space within corps. The sound guide 232 may be located on the first side wall 211 of the housing 210 to form the acoustic cavity 231. Namely, the first end of the sound guide 232 (for example, the end closest to the acoustic cavity 231) may be located on the first side wall 211 of the housing 210 , and the second end of the audio guide 232 (for example, the end more distant from the acoustic cavity 231) can be removed from the first side wall 211 and located outside the housing 210. The external audio signal can enter the audio guide 232 from the second end of the audio guide 232 and be transmitted to the acoustic cavity 231 from the first end of the audio guide 232. In some embodiments, the sound guide 232 of the acoustic structure 230 may also be located in other suitable locations. See FIG. 5-9 and in their descriptions.

In some embodiments, acoustic structure 230 may have a first resonant frequency, that is, a component with a first resonant frequency in the audio signal that can resonate in acoustic structure 230. In some embodiments, the first resonant frequency is associated with design parameters of acoustic structure 230. structures 230 may include the shape of the sound guide 232, the size of the sound guide 232, the size of the acoustic cavity 231, the acoustic impedance of the sound guide 232 or acoustic cavity 231, the roughness of the inner surface of the side wall of the sound guide 232, the thickness of the sound absorbing material (e.g., fibrous material, foam, etc.) in the sound guide channel, the stiffness of the inner wall of the acoustic cavity, etc. or their combination. In some embodiments, by setting the acoustic structure 230 design parameters, the audio signal adjusted by the acoustic structure 230 may have a resonant peak at a first resonant frequency after being converted to an electrical signal.

The geometry of the audio guide 232 may be regular and/or irregular, such as a cuboid, a cylinder, and a polygonal prism. In some embodiments, the sound guide channel 232 may be surrounded by one or more side walls. The shape of the side wall 233 of the sound guide channel 232 may be a regular geometric shape such as a cuboid and cylinder and/or an irregular shape. In some embodiments, as shown in FIG. 2A, the length of the side wall 233 of the sound guide 232 (e.g., in FIG. 2A, the sum of the length of the side wall 233 along the X-axis direction and the size of the aperture of the sound guide 232) may be the length of the body 210 in the X-axis direction. In some embodiments, the length the side wall 233 of the sound guide channel 232 may be different from the length of the housing 210. For example, in FIG. 3 depicts an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 3, the first end of the sound guide 232 is located on the first side wall 211 of the body 210, and the second end of the sound guide 232 is located away from the first side wall 211 and is located outside the body 210. The length of the side wall 233 of the opening of the sound guide 232 along the axial direction X is less than the length of body 210 along the X-axis direction.

Structural parameters such as the aperture size and length of the sound guide channel 232, and structural parameters such as the inner diameter, length and thickness of the acoustic cavity 231 can be set as needed (for example, target resonant frequency, target bandwidth, etc. .). The length of the audio guide channel refers to the total length of the audio guide channel 232 along the central axis direction of the audio guide channel (eg, the Y-axis direction in FIG. 2A). In some embodiments, the length of the audio guide 232 may be the equivalent length of the audio guide, that is, the length of the audio guide in the central axis direction plus the product of the aperture size of the audio guide and a length correction factor. As shown in FIG. 2A, the length of the acoustic cavity 231 refers to the size of the acoustic cavity 231 along the x-axis direction. The thickness of the acoustic cavity 231 refers to the size of the acoustic cavity 231 along the y-axis direction. channel 232. In some embodiments, the aperture size of the sound guide channel 232 may be no more than one and a half length of the sound guide channel 232. For example, if the cross section (for example, a cross section that is perpendicular to the direction of the central axis of the sound guide channel (for example, a section XZ)) of the sound guide 232 is circular, the size of the aperture of the sound guide 232 may be between 0.5 mm and 10 mm, and the length of the sound guide 232 may be between 1 mm and 8 mm. As another example, if the cross section of the sound guide 232 is circular, the size of the aperture of the sound guide 232 may be in the range of 1 mm to 4 mm and the length of the sound guide 232 may be 1 mm to 10 mm. In some embodiments, the inner diameter of acoustic cavity 231 may be no less than the thickness of acoustic cavity 231. In some embodiments, the inner diameter of acoustic cavity 231 may be no less than 0.8 of the thickness of acoustic cavity 231. For example, if the cross section of acoustic cavity 231 is perpendicular to to its length direction (for example, the cross section of the acoustic cavity 231 parallel to the YZ plane) is circular, the internal diameter of the acoustic cavity 231 may be in the range of 1 mm to 20 mm, and the thickness of the acoustic cavity 231 may be in the range of 1 mm to 20 mm. In some embodiments, if the cross section of the acoustic cavity 231 is circular, the internal diameter of the acoustic cavity 231 may be in the range of 1 mm to 15 mm, and the thickness of the acoustic cavity 231 may be in the range of 1 mm to 10 mm.

It should be noted that the cross-sectional shape of the acoustic cavity 231 and/or the sound guide 232 is not limited to the aforementioned circle, and may also have other shapes such as a rectangle, an ellipse, a pentagon, and the like. In some embodiments, when the cross-sectional shape of acoustic cavity 231 and/or sound guide 232 is any of the other shapes (non-circular), the inside diameter of acoustic cavity 231 and/or aperture size (or thickness, length, etc.) of the guide sound channel 232 may be equivalent to an equivalent inner diameter or an equivalent aperture size. Taking the equivalent inner diameter as an example, the equivalent inner diameter of an acoustic cavity 231 with any other cross-sectional shape can be represented by an internal diameter of an acoustic cavity and/or sound guide having a circular cross-sectional shape equal to its magnitude. For example, if the cross section of the acoustic cavity 231 is square, the equivalent inner diameter of the acoustic cavity 231 may be in the range of 1 mm to 6 mm and the thickness of the acoustic cavity 231 may be in the range of 1 mm to 4 mm. As another example, if the cross section of the acoustic cavity 231 is square, the equivalent inner diameter of the acoustic cavity 231 may be in the range of 1 mm to 5 mm and the thickness of the acoustic cavity 231 may be in the range of 1 mm to 3 mm.

In some embodiments, the implementation of the side wall 233 of the guide sound channel 232 may be made of one or more materials. Sidewall materials 233 may include, but are not limited to, one or more of semiconductor materials, metallic materials, metal alloys, organic materials, and the like. In some embodiments, the semiconductor materials may include, but are not limited to, silicon, silicon dioxide, silicon nitride, silicon carbide, and the like. In some embodiments, the metallic materials may include, but are not limited to, copper, aluminum, chromium, titanium, gold, and the like. In some embodiments, metal alloys may include, but are not limited to, copper-aluminum alloy, copper-gold alloy, titanium alloy, aluminum alloy, and the like. In some embodiments, organic materials may include, but are not limited to, polyimide (PI), perylene, polydimethylsiloxane (polydimethylsiloxane, PDMS), silicone, silica gel, and the like.

The previous description of the microphone 200 is for illustrative purposes only and is not intended to limit the scope of the present invention. Numerous changes and modifications can be made by those skilled in the art based on the principles of the present invention. However, such changes and modifications do not depart from the scope of the present invention.

In FIG. 4 is a graph of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 4, frequency response plot 410 is the frequency response of an acoustic-electric transducer (eg, acoustic-electric transducer 220), and frequency response plot 420 is the frequency response of an acoustic structure (eg, acoustic structure 230). When the frequency response 410 has a resonant peak at the frequency f0, the frequency f0 may be referred to as the resonant frequency (also referred to as the second resonant frequency) of the acoustoelectric transducer. In some embodiments, the resonant frequency of the acoustoelectric transducer is related to structural parameters of the acoustoelectric transducer. Structural parameters of the acoustoelectric transducer (eg, acoustoelectric transducer 220) may include material, size, weight, type (eg, piezoelectric type, capacitive type, etc.), arrangement method, and so on. acoustoelectric transducer. At frequency f1 of frequency response 420, the acoustic structure resonates with the received audio signal so that the signal in the frequency band containing frequency f1 is amplified, and the resonant frequency f0 may be referred to as the acoustic structure resonant frequency (also referred to as the first resonant frequency). The resonant frequency of an acoustic structure can be represented by expression (1):

(1)

(1)

where f is the resonant frequency of the acoustic structure, _c0 is the speed of sound in air, S is the cross-sectional area of the sound guide channel, l is the length of the sound guide channel, and V is the volume of the acoustic cavity.

In accordance with expression (1), the resonant frequency of the acoustic structure is related to the cross-sectional area of the guiding sound channel in the acoustic structure, the length of the guiding sound channel, and the volume of the acoustic cavity. Namely, the resonant frequency of the acoustic structure is proportionally related to the cross-sectional area of the guiding sound channel and inversely related to the length of the guiding sound channel and/or the volume of the acoustic cavity. The resonant frequency of the acoustic structure can be adjusted by setting design parameters for the acoustic structure, such as the shape of the sound guide channel, the size of the sound guide channel, the volume of the acoustic cavity, and the like. or their combination. For example, provided that the length of the sound guide channel and the volume of the acoustic cavity remain unchanged, the cross-sectional area of the sound guide channel can be reduced by reducing the aperture size of the sound guide channel, thereby lowering the resonant frequency of the acoustic structure. As another example, provided that the cross-sectional area of the sound guide channel and the length of the sound guide channel remain unchanged, the resonant frequency of the acoustic structure can be increased by reducing the volume of the acoustic cavity. As a further example, provided that the cross-sectional area and the length of the sound guide channel remain unchanged, the resonant frequency of the acoustic structure may decrease as the volume of the acoustic cavity increases.

In some embodiments, to improve the response of the microphone to an audio signal in the low frequency range, the design parameters of the acoustic design can be set so that the first resonant frequency f1 is lower than the second resonant frequency f0. In some embodiments, in order to keep the frequency response of the microphone flat over a larger frequency range, the acoustic design parameters may be set such that the difference between the first resonant frequency f1 and the second resonant frequency f0 is at least a frequency threshold. The frequency threshold can be determined according to actual requirements, for example, the frequency threshold can be set to 5Hz, 10Hz, 100Hz, 1000Hz and so on. In some embodiments, the first resonant frequency f1 may be higher than the second resonant frequency f0 or equal to the second resonant frequency f0 so that the sensitivity of the microphone's frequency response can be improved in different frequency ranges.

In some embodiments, after the audio signal has been corrected by the acoustic design, the audio signal in a certain frequency band containing the first resonant frequency f1 is amplified so that the response sensitivity of the microphone at the first frequency f1 is greater than the response sensitivity of the acoustoelectric transducer at the first frequency , thereby increasing the sensitivity and the Q value of the microphone near the first resonant frequency (for example, the increase in microphone sensitivity at frequency f1 can be represented as ΔV1 in Fig. 4). In some embodiments, by placing an acoustic structure in the microphone, the sensitivity of the microphone in various frequency ranges can be increased by 5 dBV - 40 dBV compared to the sensitivity of the acoustoelectric transducer. In some embodiments, by locating the acoustic structure in the microphone, the sensitivity of the microphone in different frequency bands can be improved by 10 dBV-20 dBV. In some embodiments, the microphone sensitivity increment may vary over different frequency ranges. For example, the higher the frequency, the greater the increase in microphone sensitivity in the corresponding frequency band. In some embodiments, the gain in microphone sensitivity may be represented by a change in the circularity of the sensitivity in the frequency domain. In some embodiments, the change in the slope of the microphone sensitivity in different frequency ranges can be in the range from 0.0005 dBV/Hz to 0.005 dBV/Hz. In some embodiments, the change in the slope of the microphone sensitivity in different frequency ranges can be in the range from 0.001 dBV/Hz to 0.003 dBV/Hz. In some embodiments, the change in the slope of the microphone sensitivity in different frequency ranges can be in the range from 0.002 dBV/Hz to 0.004 dBV/Hz.

In some embodiments, the bandwidth of the frequency response of an acoustic structure with a first resonant frequency may be represented by expression (2):

(2)

(2)

where Δf is the bandwidth of the frequency response of the acoustic structure, f is the resonant frequency of the acoustic structure, Ra' is the total acoustic impedance of the sound guide channel (including acoustic and radiation resistance of the sound guide channel), Ma' is the overall sound quality of the sound guide channel (including sound the quality of the sound guide channel and the quality of the emitted sound), and wr is the resonant circular frequency of the acoustic structure.

According to expression (2), if the resonant frequency of the acoustic structure is determined, the bandwidth of the acoustic structure can be adjusted by adjusting the acoustic impedance of the sound guide channel. In some embodiments, an acoustic impedance component may be located in the microphone and the acoustic impedance value of the acoustic impedance component may be controlled by adjusting the aperture size, thickness, porosity, etc. component with acoustic impedance, thus adjusting the bandwidth of the acoustic design. For more information on the acoustic impedance component, refer to FIG. 10-16 and their descriptions.

In some embodiments, the acoustic impedance of the sound guide can be adjusted by adjusting the roughness of the inner side wall surface of the sound guide, thereby adjusting the bandwidth of the acoustic design's frequency response. In some embodiments, the implementation of the roughness of the inner surface of the side wall of the guide sound channel may be less than or equal to 0.8. In some embodiments, the implementation of the roughness of the inner surface of the side wall of the guide sound channel may be less than or equal to 0.4. Taking the -3 dB bandwidth of the microphone as an example, adjusting the design parameters of the acoustic design, the -3 dB bandwidth of the microphone can be 100 Hz to 1500 Hz. In some embodiments, by adjusting the roughness of the inner surfaces of the sound guide sidewalls corresponding to different acoustic designs, the -3 dB bandwidth increment of microphones at different resonant frequencies can be different. For example, when adjusting the roughness of the inner surfaces of the side walls of the sound guide channels corresponding to different acoustic structures, the higher the resonant frequency of the acoustic structure, the greater the -3 dB gain of the microphone bandwidth at its corresponding resonant frequency. In some embodiments, a 3 dB increase in microphone bandwidth at various resonant frequencies may be represented by a change in the slope of the bandwidth. In some embodiments, the -3dB bandwidth slope of the microphone over the frequency range may be 0.01 Hz/Hz - 0.1 Hz/Hz. In some embodiments, the -3dB bandwidth slope of the microphone over the frequency range may be 0.05 Hz/Hz - 0.1 Hz/Hz. In some embodiments, the -3dB bandwidth slope range of the microphone over the frequency range may be 0.02 Hz/Hz - 0.06 Hz/Hz.

In some embodiments, the gain (also referred to as gain) of an acoustic design for the sound pressure of an audio signal can be expressed as follows (3):

(3)

(3)

where Ap is the sound pressure gain, l0 is the length of the guiding sound channel, s is the cross-sectional area of the guiding sound channel, and V is the volume of the acoustic cavity.

According to expression (3), the sound pressure gain of an acoustic structure for a sound signal is related to the length of the sound guide channel, the cross-sectional area of the sound guide channel, and the volume of the acoustic cavity. Namely, the sound pressure gain of an acoustic structure for a sound signal is proportionally correlated with the length of the sound guide channel and the volume of the acoustic cavity, and is inversely correlated with the cross-sectional area of the sound guide channel.

According to expression (1), expression (3) can also be converted to expression (4):

(4)

(4)

where AP is the sound pressure gain, f is the resonant frequency of the acoustic structure, c ₀ is the speed of sound in air, l is the length of the directing sound channel, and R is the radius of the acoustic cavity.

It can be seen from expression (4) that in a situation where other conditions (for example, the length of the sound guide channel, the radius of the acoustic cavity, etc.) are determined, the sound pressure gain factor AP of the acoustic structure for the sound signal is related to the resonant frequency f of the acoustic structure . Namely, the sound pressure gain AP is inversely correlated with the resonant frequency f of the acoustic structure, and the lower the resonant frequency f, the greater the sound pressure gain AP, and vice versa. That is, the acoustic design has a greater gain for the audio signal at a lower resonant frequency (eg, at a resonant frequency in the mid and low frequency band). By setting the design parameters of an acoustic design, it is possible to adjust the resonant frequency, bandwidth, gain of a particular frequency component in the audio signal, sensitivity increment, Q value, etc. microphone. The design parameters of the acoustic design may include the shape of the sound guide channel, the size of the sound guide channel, the size of the acoustic cavity, the acoustic impedance of the sound guide channel or acoustic cavity, the roughness of the inner surface of the side wall of the sound guide channel, the thickness of the sound absorbing material in the sound guide channel, etc. or their combination.

In FIG. 5 shows an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 5, the microphone 500 may include a housing 510, at least one acoustoelectric transducer 520, and an acoustic structure 530. One or more components of the microphone 500 shown in FIG. 5 may be the same or similar to one or more components of the microphone 200. For example, the housing 510, the acoustoelectric transducer 520, the aperture 521 of the acoustoelectric transducer 520, the acoustic cavity 540, the ASIC 550, and so on. the microphone 500 may be the same or similar to the housing 210, the acoustoelectric transducer 220, the opening 221 of the acoustoelectric transducer 220, the acoustic cavity 240, the ASIC 250, and so on. microphone 200 shown in FIG. 3. The acoustic structure 530 of the microphone 500 differs from the acoustic structure 230 of the microphone 200 in the shape and/or location of the sound guide 532 in the acoustic structure 530 of the microphone 500.

As shown in FIG. 5, the acoustic structure 530 may include an acoustic cavity 531 and a sound guide duct 532. The acoustic cavity 531 may be acoustically coupled to the acoustoelectric transducer 520 through an opening 521 of the acoustoelectric transducer 520. The acoustic cavity 531 may be acoustically coupled to the external environment of the microphone 500 through the sound guide duct. 532. The first end of the guide sound channel 532 is located on the first side wall 511 of the housing 510, and the second end of the guide sound channel 532 is located in the acoustic cavity 531. The side wall 533 of the guide sound channel 532 extends from the first side wall 511 into the interior of the acoustic cavity 531. An external audio signal is introduced into the audio guide 532 from the first end of the audio guide 532 and is transmitted to the acoustic cavity 531 from the second end of the audio guide 532. By positioning the second end of the audio guide 532 so that it extends into the acoustic cavity 531, the length of the sound guide channel 532 and the volume of the acoustic cavity 531 can be further increased without increasing the size of the microphone 500. According to expression (1), by increasing the length of the sound guide channel 532 and the volume of the acoustic cavity 531, it is possible to reduce the resonant frequency of the acoustic structure 530 so that the frequency response of the microphone 500 has a resonant peak at a lower resonant frequency.

In some embodiments, the resonant frequency of acoustic structure 530 may be further controlled by length, shape, and so on. audio guide 532. Just by way of example, in FIG. 6 schematically shows an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 6, the sound guide 532 is curved at a right angle, the first end of the sound guide 532 is located on the first side wall 511 of the housing 510, the second end of the sound guide 532 is located in the acoustic cavity 531, the side wall 533 of the sound guide 532 extends from the first side wall walls 511 inside the acoustic cavity 531. By positioning the sound guide 532 in a curved manner, the length of the sound guide 532 can be increased while the size of the acoustic cavity 531 is slightly reduced, thus the resonant frequency of the acoustic structure 530 can be lowered and the sensitivity and value The Q response of the microphone 500 at a lower frequency can be increased. In some embodiments, the sound guide 532 is not limited to the aforementioned linear configuration (e.g., as shown in FIG. 5) curved at a right angle (e.g., as shown in FIG. 6) and may also have a different shape, such as an arcuate curved configuration designed to reduce acoustic impedance. In some embodiments, the angle of curvature between the two segments of the audio guide can be adjusted to control the acoustic impedance. For example, the angle of curvature between the center lines of two segments may be between 60° and 150°. As another example, the angle of curvature between the center lines of these two segments may be in the range of 60° to 90°. As a further example, the angle of curvature between the center lines of these two segments may be in the range of 90° to 120°. As another further example, the angle of curvature between the center lines of these two segments may be in the range of 120° to 150°.

In some embodiments, the first end of the sound guide 532 may be away from the first side wall 511 and located outside the housing 510, the second end of the sound guide 532 may be located within the acoustic cavity 531, and the side wall 533 of the sound guide 532 may extend from the first side wall. housing walls 511 into acoustic cavity 531. Just by way of example, in FIG. 7 depicts an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 7, the audio guide 532 of the microphone 500 extends through the first side wall 511 of the housing 510. The first end of the audio guide 532 is spaced from the first side wall 511, extends outward of the housing 510, and is located on the outside of the housing 510. The second end of the audio guide 532 is also spaced from the first side wall 511, extends into the acoustic cavity 531 and the second end of the guide sound channel 532 is located in the acoustic cavity 531. channel 532.

In FIG. 8 is a schematic representation of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 8, a microphone 800 may include a housing 810, at least one acoustoelectric transducer 820, and an acoustic structure 830. One or more components of the microphone 800 shown in FIG. 8 may be the same or similar to one or more components of the microphone 500. For example, housing 810, acoustoelectric transducer 820, aperture 821 of acoustoelectric transducer 820, acoustic cavity 840, ASIC 850, and so on. the microphone 800 may be the same or similar to the housing 510, the acoustoelectric transducer 520, the aperture 521 of the acoustoelectric transducer 520, the acoustic cavity 540, the ASIC 550, and so on. microphone 500 shown in FIG. 5. The difference between the microphone 800 and the microphone 500 is the shape and/or location of the sound guide 832 of the acoustic structure 830.

As shown in FIG. 8, the acoustic structure 830 may include an acoustic cavity 831 and a sound guide 832. The sound guide 832 may include one or more side walls, such as a side wall 833 and a side wall 834, to form the sound guide 832. In some embodiments, the side wall wall 833 and side wall 834 may be a single part or different parts of the same side wall of the sound guide 832. For example, side wall 833 and side wall 834 may be integrally formed. In some embodiments, sidewall 833 and sidewall 834 may be independent elements. In some embodiments, one or more side walls of the audio guide duct 832 may form a certain angle of inclination with the central axis 835 of the audio guide 832. channel 832 can form a tilt angle α. In some embodiments, as shown in FIG. 8, it is assumed that the direction in which the central axis of the sound guide 832 points towards the acoustic cavity 831 is a positive direction. If the aperture size of the sound guide 832 shrinks inwards along the positive direction of the central axis 835, that is, if the side wall 833 and/or the side wall 834 of the sound guide 832 extend in the direction of the central axis 835 along the positive direction of the central axis 835 of the sound guide 832, the value of the tilt angle α can be any value between 0° and 90°. For example, the value of the tilt angle α may be any value between 0° and 30°. As another example, the value of the tilt angle α may be any value between 30° and 45°. As a further example, the value of the tilt angle α can be any value between 45° and 60°. As another further example, the value of the angle α of inclination can be any value between 60° and 90°.

In some embodiments, as shown in FIG. 9, if the aperture size of the sound guide duct 832 that extends outward along the positive direction of the central axis 835, that is, if the side wall 833 and/or the side wall 834 of the sound guide tube 832 extends along the positive direction of the central axis 835 of the sound guide 832 in the direction from the central axis 835, the value of the angle β of inclination formed by the side wall of the audio guide duct 832 (for example, the side wall 833 and/or side wall 834 of the audio guide duct) and the central axis 835 of the audio guide can be any value between 0° and 90° . For example, the value of the tilt angle β may be any value between 0° and 10°. As another example, the value of the tilt angle β may be any value between 10° and 20°. As another example, the value of the tilt angle β may be any value between 0° and 30°. As yet another example, the value of the tilt angle β may be any value between 30° and 45°. As a further example, the value of the tilt angle β may be any value between 45° and 60°. As another further example, the value of the angle β of inclination can be any value between 60° and 90°.

By setting a certain angle of inclination between the side wall of the sound guide 832 and the center axis of the sound guide 832, the position of the resonant frequency of the microphone 800 can be adjusted, provided that the length of the sound guide 832 and the outer diameter of the first end of the sound guide 832 (for example, at the first side wall 811 of the housing 810 or the end remote from the first side wall 811 and located outside the microphone 800) remain unchanged. For example, if the size of the aperture of the audio guide 832 decreases inwardly along the positive direction of the central axis 835, the cross-sectional size of the second end (for example, the end extending into the acoustic cavity 831) of the audio guide 832 can be reduced without changing the length of the audio guide 832 and the size of the aperture of the first end of the sound guide duct 832 thus lowers the resonant frequency of the acoustic structure 830. As another example, if the size of the aperture of the sound guide 832 increases while extending outward along the positive direction of the central axis 835, the cross-sectional size of the second end of the sound guide 832 may increase without changing the length of the sound guide 832 and the aperture size of the first end of the sound guide 832, thereby increasing the resonant frequency of the acoustic structure 830.

In some embodiments, if the cross section of the acoustic cavity 831 (e.g., a cross section parallel to the XZ plane) is circular, the aperture size of the first end of the sound guide 832 may be no more than 1.5 times the length of the sound guide 832. B In some embodiments, the aperture size of the first end of the sound guide 832 may be in the range of 0.1 mm to 3 mm, and the length of the sound guide 832 may be in the range of 1 mm to 4 mm. In some embodiments, the aperture size of the first end of the sound guide 832 may be in the range of 0.1 mm to 2 mm and the length of the sound guide 832 may be in the range of 1 mm to 3 mm.

In FIG. 10 is a schematic representation of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 10, a microphone 1000 may include a housing 1010, at least one acoustoelectric transducer 1020, and an acoustic structure 1030. One or more components of the microphone 1000 shown in FIG. 10 may be the same or similar to one or more components of the microphone 200 shown in FIG. 2A. For example, a housing 1010, an AE transducer 1020, an opening 1021 of an AE transducer 1020, an acoustic cavity 1040, an ASIC 1050, and so on. the microphone 1000 may be the same or similar to the housing 210, the acoustic-electric transducer 220, the opening 221 of the acoustic-electric transducer 220, the acoustic structure 230, the acoustic cavity 240, and so on. microphone 200 shown in FIG. 3.

In some embodiments, the difference between microphone 1000 and microphone 200 is that microphone 1000 may further comprise an acoustic impedance component 1060. According to expression (2), the acoustic impedance component 1060 may be used to control the bandwidth of the acoustic structure 1030. In some embodiments, the acoustic impedance component 1060 may comprise a membrane acoustic impedance component, a mesh acoustic impedance component , a component with acoustic resistance in the form of a plate, etc. or their combination. In some embodiments, the acoustic impedance component 1060 may comprise a single layer damping component, a multilayer damping component, and so on. or other damping components. The multilayer damping component may comprise a single multilayer damping component or a damping component composed of a plurality of single layer damping components.

In some embodiments, the acoustic impedance component 1060 may be located on the outer surface of the side wall 1033 forming the sound path 1032 away from the first side wall 1011 of the housing, within the sound path 1032, on the inner surface of the first side wall 1011, on the outer surface the first side wall 1011, in the acoustic cavity 1031, on the inner surface of the second side wall 1051 for the hole 1021 of the acoustoelectric transducer 1020, on the outer surface of the second side wall 1051, in the hole 1021 of the acoustoelectric transducer 1020, and the like. or in their combination.

As shown in FIG. 10, the acoustic impedance component 1060 may be positioned as a single layer damping component on the outer surface of the sidewall 1033 forming the sound guide channel 1032, away from the first sidewall 1011. Material, size, thickness, etc. acoustic impedance component 1060 can be installed according to actual requirements. For example, the length of the acoustic impedance component 1060 along the X-axis direction may be equal to the sum of the lengths of the sound guide 1032 and the side wall 1033 of the sound guide 1032. As another example, the length of the acoustic impedance component 1060 along the X-axis direction may be equal to or greater than aperture of the sound guide duct 1032. As another example, the width of the acoustic impedance component 1060 along the z-direction may be equal to or greater than the width of the side wall 1033 of the sound guide 1032.

As shown in FIG. 11, the acoustic impedance component 1060 may be disposed on the inner surface of the first side wall 1011 in the form of a single layer damping component. In some embodiments, acoustic impedance component 1060 may be attached to one or more side walls of housing 1010 (eg, side wall 1011, side wall 1012, side wall 1013, etc. of housing 1010). Material, size, thickness, etc. acoustic impedance component 1060 can be installed according to actual requirements. For example, the length of the acoustic impedance component 1060 along the X-axis direction may be less than or equal to the length of the side wall 1011 of the housing 1010 along the X-axis direction. As another example, the width of the acoustic impedance component 1060 along the Z-axis direction may be less than or equal to the width of the side wall 1011 of the body 1010 along the z-axis direction. As another example, the size of the acoustic impedance component 1060 may be larger than, equal to, or smaller than the aperture size of the sound guide 1032.

As shown in FIG. 12, the acoustic impedance component 1060 may be positioned within the acoustic cavity 1031 as a single layer damping component that may or may not be connected to the sidewall defining the sound path 1032. For example, both ends of the acoustic impedance component 1060 may be attached to side wall 1011 and/or side wall 1013 of housing 1010, respectively. As shown in FIG. 13, the acoustic impedance component 1060 may be located on the outer surface of the second side wall 1051 configured to form the opening 1021 of the acoustoelectric transducer 1020 as a single layer damping component that may or may not be physically connected to the second side wall 1051. For example, the two ends of the acoustic impedance component 1060 may be attached to the side wall 1012 and the side wall 1013 of the housing 1010, respectively. As another example, the acoustic resistance component 1060 may be physically attached to the second side wall 1051. In some embodiments, the size of the acoustic resistance component 1060 may be the same or different than the second side wall 1051. For example, the length of the acoustic resistance component 1060 along the X-axis direction may be greater than, equal to, or less than the sum of the length of the second side wall 1051 along the X-axis and the aperture size of the hole 1021. In some embodiments, the size of the acoustic impedance component 1060 can be larger than the size of the hole 1021 of the acoustoelectric transducer 1020.

As shown in FIG. 14, acoustic impedance component 1060 may be positioned in sound guide 1032 as a single layer damping component. Component 1060 with acoustic resistance can be fully or partially attached to the side wall 1033 of the audio guide channel. In some embodiments, the implementation of the material, size, thickness, etc. acoustic impedance component 1060 can be installed according to actual requirements. For example, the thickness of the acoustic impedance component 1060 along the Y-axis direction may be greater than, equal to, or less than the length of the audio guide 1032 along the Y-axis direction. As another example, the length of the acoustic impedance component 1060 along the X-axis direction may be greater than, equal to or smaller than the aperture size of the sound guide 1032.

In FIG. 15 is a schematic representation of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 15, the acoustic impedance component 1060 may be a two-layer damping component, and the two-layer damping component may comprise a first acoustic impedance component 1061 and a second acoustic impedance component 1062. The first acoustic impedance component 1061 may be located on the outer surface of the side wall 1033 forming the sound guide channel 1032 away from the first side wall 1011 of the housing 1010 and may or may not be physically attached to the outer surface of the first side wall 1011. The second component 1062 with acoustic resistance may be located on the inner surface of the first side wall 1011 and may or may not be physically attached to the inner surface of the first side wall 1011. In some embodiments, the position, size, material, etc. the first acoustic impedance component 1061 and the second acoustic impedance component 1062 may be set according to actual requirements and may be the same or different. For example, the first acoustic impedance component 1061 and/or the second acoustic impedance component 1062 may be located in the acoustic cavity 1031 (e.g., be physically attached to the second side wall 1051, the first side wall 1011, the side wall 1012, the side wall 1013, etc.). .d.). As another example, the first acoustic impedance component 1061 and/or the second acoustic impedance component 1062 may be located in the aperture 1021 of the acoustoelectric transducer 1020. As a further example, the first acoustic impedance component 1061 and/or the second acoustic impedance component 1062 may be located in the sound guide duct 1032. As yet another additional example, the first acoustic impedance component 1061 and/or the second acoustic resistance component 1062 may be located on the outer surface of the side wall 1033 of the sound guide duct 1032.

In some embodiments, the acoustic impedance value of the acoustic impedance component 1060 can be changed by adjusting the parameters of the acoustic impedance component 1060. In some embodiments, the acoustic impedance component 1060 parameters may include, but are not limited to, thickness, diameter, porosity, and so on. component 1060 with acoustic impedance. In some embodiments, the thickness of acoustic impedance component 1060 may be 20 microns - 300 microns. In some embodiments, acoustic impedance component 1060 may have a thickness in the range of 10 microns to 400 microns. In some embodiments, the aperture size of the acoustic impedance component 1060 may be 20-300 microns. In some embodiments, the aperture size of the acoustic impedance component 1060 may be 30-300 microns. In some embodiments, the aperture size of the acoustic impedance component 1060 may be 10-400 microns. In some embodiments, the implementation of the porosity of the component 1060 with acoustic resistance may be 10%-50%. In some embodiments, the implementation of the porosity of the component 1060 with acoustic resistance may be 30%-50%. In some embodiments, the implementation of the porosity of the component 1060 with acoustic resistance may be 20%-40%. In some embodiments, the implementation of the porosity of the component 1060 with acoustic resistance may be 25%-45%. In some embodiments, the acoustic impedance value of the acoustic impedance component 1060 may be in the range of 1 Pa⋅s/m to 100 Pa⋅s/m. In some embodiments, by adjusting the parameters of the acoustic impedance component 1060 (e.g., diameter, thickness, porosity, etc.), the acoustic impedance value of the acoustic impedance component 1060 can be set to 10 Pa⋅s/m - 90 Pa⋅ s/m, 20 Pa⋅s/m - 80 Pa⋅s/m, 30 Pa⋅s/m - 70 Pa⋅s/m, 40 Pa⋅s/m - 60 Pa⋅s/m, 50 Pa⋅s / m.

In some embodiments, by placing an acoustic impedance component in the microphone, the acoustic impedance of the microphone's acoustic design can be increased, thereby adjusting the bandwidth (-3 dB level) and/or the Q value of the microphone's frequency response. In some embodiments, acoustic impedance components with different acoustic impedance values may have different degrees of influence on the Q value of the microphone's frequency response. In FIG. 16 shows the frequency response of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 16, the horizontal axis represents the frequency expressed in Hz and the vertical axis represents the frequency response of the microphone expressed in dB. Graph 1610 represents the frequency response of a microphone without an acoustic impedance component. Plot 1615 represents the frequency response of a microphone with an acoustic impedance component having an acoustic impedance value of 3 Pa⋅s/m. Plot 1620 represents a microphone with an acoustic impedance component having an acoustic impedance value of 20 Pa⋅s/m. Plot 1630 represents the frequency response of a microphone with an acoustic impedance component having an acoustic impedance value of 65 Pa⋅s/m. Plot 1640 represents the frequency response of a microphone with an acoustic impedance component having an acoustic impedance value of 160 Pa⋅s/m. Plot 1650 represents the frequency response of a microphone with an acoustic impedance component having an acoustic impedance value of 4000 Pa⋅s/m. In FIG. 16, it can be seen that as the acoustic impedance value of the acoustic impedance component increases, the bandwidth of the microphone frequency response curve increases and the frequency response of the microphone decreases. Therefore, the Q value of the microphone can be adjusted by setting the acoustic impedance value of the component with the acoustic impedance of the microphone. In some embodiments, as the acoustic impedance value of the acoustic impedance component increases, the Q value of the microphone may decrease. Therefore, the acoustic impedance value of the acoustic impedance component can be selected according to actual requirements to obtain the target Q value and the target bandwidth of the microphone. For example, the acoustic impedance value of the acoustic impedance component may be set to not more than 20 Pa⋅s/m, and the corresponding target bandwidth (in terms of -3 dB) is not less than 300 Hz. As another example, the acoustic impedance value of the acoustic impedance component may be no more than 100 Pa⋅s/m and the corresponding target bandwidth (in -3 dB level) is no less than 1000 Hz.

In FIG. 17 is a schematic representation of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 17, a microphone 1700 may include a housing 1710, at least one acoustic-electric transducer 1720, an acoustic structure 1730, an acoustic cavity 1740, and an acoustic structure 1770 (also referred to as a second acoustic structure). One or more components of the microphone 1700 shown in FIG. 17 may be the same or similar to one or more components of the microphone 200 shown in FIG. 3. For example, a housing 1710, an acoustic-electric transducer 1720, an acoustic structure 1730, an acoustic cavity 1740, an ASIC 1750, etc. microphone 1700 may be the same or similar to housing 210, at least one acoustoelectric transducer 220, acoustic structure 230, acoustic cavity 240, ASIC 250, etc., microphone 200 shown in FIG. 3. The difference between microphone 1700 and microphone 200 is that microphone 1700 may further comprise a second acoustic structure 1770. In some embodiments, second acoustic structure 1770 may be positioned in series with acoustic structure 1730. Second acoustic structure 1770 may be positioned in series with acoustic structure 1730, which means that the second acoustic cavity 1771 of the second acoustic structure 1770 can be acoustically coupled to the acoustic cavity 1731 of the acoustic structure 1730 via the sound guide 1732 of the acoustic structure 1730. In some embodiments, the second acoustic cavity 1771 of the second acoustic structure 1770 is acoustically coupled with the environment of the microphone 1700 through the second audio guide 1772. In some embodiments, the audio guide 1732 may be located on the sidewall 1711 that forms the acoustic cavity 1731, and the second sound channel 1772 may be located on the side wall 1712 forming the second acoustic cavity 1771.

In some embodiments, the external audio signal received by the microphone 1700 may first be adjusted (e.g., filtered) by the second acoustic structure 1770, then transmitted to the acoustic structure 1730 via the audio guide channel 1732, and the acoustic structure 1730 may re-adjust the audio signal. The audio signal, after secondary regulation, further enters the acoustic cavity 1740 of the microphone 1700 through the opening 1721, thus forming an electrical signal.

In some embodiments, the design parameters of the second acoustic structure 1770 are the same or different from the design parameters of the acoustic structure 1730. For example, the shape of the acoustic structure 1770 may be cylindrical and the shape of the acoustic structure 1730 may be cylindrical. As another example, the acoustic impedance value of the acoustic structure 1770 may be less than the acoustic impedance value of the acoustic structure 1730. See FIG. 2A, FIG. 3, fig. 5-15 and in the accompanying descriptions.

In some embodiments, the implementation of the second acoustic structure 1770 may have a resonant frequency (which may also be referred to as the third resonant frequency). The frequency component of the audio signal at the third resonant frequency may resonate such that the second acoustic structure 1770 may amplify the frequency component of the audio signal near the third resonant frequency. Acoustic structure 1730 may have a first resonant frequency. The frequency component of the audio signal amplified by the second acoustic structure 1770 may resonate at the first resonant frequency such that the acoustic structure 1730 may continue to amplify the frequency component of the audio signal near the first resonant frequency. Assuming that a particular acoustic design has a good amplifying effect only for the audio component in a certain frequency range, for ease of understanding, the audio signal amplified by the acoustic design can be considered as a sub-band audio signal at the corresponding resonant frequency of the acoustic design. For example, the aforementioned audio signal amplified by the second acoustic structure 1770 may be considered a sub-band audio signal at the third resonant frequency, and the audio signal further amplified by the acoustic structure 1730 may form another sub-band audio signal at the first resonant frequency. The amplified audio signal is transmitted to the acoustoelectric transducer 1720, thus generating the corresponding electrical signal. Thus, the acoustic structure 1730 and the second acoustic structure 1770 can respectively increase the Q value of the microphone 1700 in the frequency bands including the first resonant frequency and the third resonant frequency, thereby improving the sensitivity of the microphone 1700. (in relation to the acoustic transducer) may be the same or different. For example, if the third resonant frequency is higher than the first resonant frequency, the response sensitivity of the microphone 1700 at the third resonant frequency is greater than the response sensitivity of the microphone 1700 at the first resonant frequency. In some embodiments, the resonant frequency of the acoustic structure 1770 and/or the acoustic structure 1730 may be controlled by adjusting the design parameters of the acoustic structure 1770 and/or the acoustic structure 1730. In some embodiments, the first resonant frequency corresponding to the acoustic structure 1730 and the third resonant frequency corresponding to the second acoustic structure 1770 can be set according to actual conditions. For example, the first resonant frequency and the third resonant frequency may both be lower than the second resonant frequency so that the sensitivity of the microphone 1700 in the midband and lowband can be increased. As another example, the absolute value of the difference between the first resonant frequency and the third resonant frequency may be less than a frequency threshold (eg, 100 Hz, 200 Hz, 1000 Hz, etc.) so that the sensitivity and Q value of the microphone is 1700 could be improved in a certain frequency range. As a further example, the first resonant frequency may be higher than the second resonant frequency and the third resonant frequency may be lower than the second resonant frequency, so that the frequency response graph of the microphone 1700 may be flatter and the sensitivity of the microphone 1700 over a relatively wide frequency band. could be improved.

The previous description of the microphone 1700 is for illustrative purposes only and is not intended to limit the scope of the present invention. Various changes and modifications may be made by those skilled in the art based on the description of the present invention. In some embodiments, the implementation of the microphone 1700 may contain multiple (eg, 3, 5, 11, 14, 64, etc.) acoustic structures. In some embodiments, acoustic structures in a microphone may be connected in series, in parallel, or a combination of the two. In some embodiments, the values of the first resonant frequency, the second resonant frequency, and the third resonant frequency may be adjusted according to actual requirements. For example, the first resonant frequency and/or the third resonant frequency may be lower than, equal to, or higher than the second resonant frequency. As another example, the first resonant frequency may be lower than, equal to, or higher than the third resonant frequency. These changes and modifications still remain within the protection scope of the present invention.

In FIG. 18 is a schematic representation of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 18, a microphone 1800 may include a housing 1810, at least one acoustic-electric transducer 1820, an acoustic structure 1830, a second acoustic structure 1870, and a third acoustic structure 1880.

In some embodiments, housing 1810 may be used to house one or more components of microphone 1800 (e.g., acoustoelectric transducer 1820, acoustic structure 1830, and at least a portion of second acoustic structure 1870 and/or third acoustic structure 1880). One or more components in microphone 1800 may be the same or similar to one or more components of microphone 1700 shown in FIG. 17. For example, a housing 1810, at least one acoustoelectric transducer 1820, an acoustic structure 1830, an acoustic cavity 1840, an ASIC 1850, and so on. may be the same or similar to the housing 1710, at least one acoustoelectric transducer 1720, acoustic structure 1730, acoustic cavity 1740, and ASIC 1750 shown in FIG. 17. The difference between the microphone 1800 and the microphone 1700 is that the number of acoustic structures contained in the microphone 1800 and the way they are connected, etc. may differ from the 1700 microphone.

In some embodiments, housing 1810 may be internally hollow and may form one or more acoustic cavities, such as acoustic cavity 1840, acoustic structure 1830, second acoustic structure 1870, third acoustic structure 1880, and so on. In some embodiments, the implementation of the acoustic transducer 1820 may be located in the acoustic cavity 1840. In some embodiments, the implementation of the acoustic structure 1820 may include a hole 1821. may include a sound guide channel 1831 and an acoustic cavity 1832, a second acoustic structure 1870 may include a second sound guide channel 1871 and a second acoustic cavity 1872, a third acoustic structure 1880 may include a third sound guide channel 1881, a fourth sound guide channel 1882, and a third acoustic cavity 1883 The acoustic cavity 1832 may be acoustically coupled to the third acoustic cavity 1883 via a third sound path 1881. The acoustic cavity 1832 may be an acoustic 1831. Second acoustic cavity 1872 may be acoustically coupled to third acoustic cavity 1883 via fourth acoustic guide 1882. Second acoustic cavity 1872 may be acoustically coupled to acoustic microphone 1800 environment via second sound guide channel 1871. The third acoustic cavity 1883 may be acoustically coupled to the acoustoelectric transducer 1820 through an opening 1821 of the acoustoelectric transducer 1820.

In some embodiments, the acoustic structure 1830 has a first resonant frequency, the acoustoelectric 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 resonant frequency, the third resonant frequency, and/or the fourth resonant frequency may be the same as or different from the second resonant frequency. In some embodiments, the first resonant frequency, the third resonant frequency, and/or the fourth resonant frequency may be the same or different. For example, the first resonant frequency may be higher than 10000 Hz, the second resonant frequency may be in the range of 500 Hz to 700 Hz, the third resonant frequency may be in the range of 700 Hz to 1000 Hz, and the fourth resonant frequency may be in the range of 1000 Hz up to 1300 Hz, whereby the sensitivity of the 1800 microphone in a wider frequency band can be improved. As another example, the first resonant frequency, the third resonant frequency, and the fourth resonant frequency may be lower than the second resonant frequency so that the frequency response and sensitivity of the microphone 1800 in the mid and low frequency bands can be improved. As another example, one part of the resonant frequencies such as the first resonant frequency, the third resonant frequency, and the fourth resonant frequency may be lower than the second resonant frequency, and another part of the resonant frequencies may be higher than the second resonant frequency, so that the sensitivity of the 1800 microphone over a wider bandwidth could be improved. As another example, the first resonant frequency, the third resonant frequency, and the fourth resonant frequency may be located in a specific frequency range, so that the sensitivity and Q value of the microphone 1800 in that specific frequency range can be improved.

When using the microphone 1800 to process the audio signal, the audio signal may enter the acoustic cavity 1832 of the acoustic structure 1830 through the sound guide 1831 and/or be introduced into the second acoustic cavity 1872 of the second acoustic structure 1870 through the second sound guide channel 1871. The acoustic structure 1830 can adjust the sound a signal for generating a first subband audio signal having a first resonant peak at a first resonant frequency. Similarly, the second acoustic structure 1870 may adjust the audio signal to generate a second sub-band audio signal having a second resonant peak at a third resonant frequency. The first sub-band audio signal and/or the second sub-band audio signal generated after adjustment by the acoustic structure 1830 and/or the second acoustic structure 1870 may be introduced into the third acoustic cavity 1883 through the third audio guide channel 1881 and the fourth audio guide channel 1882, respectively. The third acoustic structure 1880 may continue to adjust the first sub-band audio signal and the second sub-band audio signal to generate a third sub-band audio signal having a third resonant peak at a fourth resonant frequency. The first sub-band audio signal, the second sub-band audio signal, and the third sub-band audio signal generated by the acoustic structure 1830, the second acoustic structure 1870, and the third acoustic structure 1880 may be transmitted through the opening 1821 of the acoustic-electric transducer 1820 to the acoustic-electric transducer 1820. The acoustic-electric transducer 1820 may generate an electrical a signal corresponding to the first subband audio signal, the second subband audio signal, and the third subband audio signal.

It should be noted that the acoustic structures contained in the microphone 1800 are not limited to the acoustic structure 1830, the second acoustic structure 1870, and the third acoustic structure 1880 shown in FIG. 18. The set of acoustic structures contained in the microphone 1800, the design parameters of acoustic structures, the method of connecting acoustic structures, etc. can be determined according to actual requirements (eg, target resonant frequency, target sensitivity, number of subband electrical signals, etc.). Just for example, in Fig. 19 is a schematic representation of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 19, the microphone 1900 may include a housing 1910, an acoustic-electric transducer 1920, an acoustic cavity 1940, an acoustic structure 1901, an acoustic structure 1902, an acoustic structure 1903, an acoustic structure 1904, an acoustic structure 1905, an acoustic structure 1906, and an acoustic structure 1907. The acoustic-electric transducer 1920 may be located in acoustic cavity 1940. Acoustic-electric transducer 1920 may include an opening 1921. Acoustic structure 1907 may include acoustic cavity 1973 and six sound guide channels associated with acoustic structure 1901, acoustic structure 1902, acoustic structure 1903, acoustic structure 1904, acoustic structure 1905 and acoustic design 1906, respectively. The components of microphone 1900 and the audio signal processing are similar to microphone 1800 in FIG. 18 and not here their description is not repeated.

In FIG. 20 schematically shows an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 20, a microphone 2000 may include a housing 2010, an acoustic cavity 2040, an acoustic-electric transducer 2020, and an acoustic structure 2030. In some embodiments, the acoustic-electric transducer 2020 may be located in the acoustic cavity 2040. In some embodiments, the acoustic-electric transducer 2020 may comprise a plurality of acoustic-electric transducers, for example , an acoustic-electric transducer 2021, a second acoustic-electric transducer 2022, a third acoustic-electric transducer 2023, a fourth acoustic-electric transducer 2024, a fifth acoustic-electric transducer 2025, and a sixth acoustic-electric transducer 2026. acoustic structure 2032, third acoustic structure 2033, fourth acoustic structure 2034, fifth a an acoustic structure 2035; and a sixth acoustic structure 2036. In some embodiments, each acoustic structure in microphone 2000 corresponds to one acoustoelectric transducer. For example, the acoustic structure 2031 is acoustically connected to the acoustoelectric transducer 2021 through the opening of the acoustoelectric transducer 2021; transducer 2023, the fourth acoustic structure 2034 is acoustically connected to the fourth acoustoelectric transducer 2024 through the hole of the fourth acoustoelectric transducer 2024, the fifth acoustic structure 2035 is acoustically connected to the fifth acoustoelectric transducer 2025 through the hole of the fifth acoustoelectric transducer 2025 and the sixth acoustic structure 2036 is acoustically connected to the sixth acoustoelectric transducer 2026 through the hole of that acoustoelectric transducer 2026. Taking the sixth acoustic structure 2036 as an example for illustration, the sixth acoustic structure 2036 includes a sound guide channel 2061 and an acoustic cavity 2062. The sixth acoustic structure 2036 is acoustically coupled to the external environment of the microphone 2000 via the sound guide channel 2061 to receive an audio signal. . The acoustic cavity 2062 of the sixth acoustic structure 2036 is acoustically coupled to the acoustoelectric transducer 2026 through the opening of the acoustoelectric transducer 2026. In some embodiments, all acoustic structures in a microphone may correspond to a single acoustic transducer. For example, the sound guide channels of the acoustic structure 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 coupled to the external environment of the microphone 2000, respectively, their acoustic cavities may be acoustically coupled to an acoustic transducer. As another example, the microphone 2000 may comprise a plurality of acoustic-electric transducers, a portion of the acoustic structures of acoustic structure 2031, second acoustic structure 2032, third acoustic structure 2033, fourth acoustic structure 2034, fifth acoustic structure 2035, and sixth acoustic structure 2036 may be acoustically coupled to one an acoustoelectric transducer from a plurality of acoustic transducers, and another part of the acoustic structures can be acoustically connected with other acoustoelectric transducers. As yet another example, the microphone 2000 may comprise a plurality of acoustoelectric transducers, and the acoustic cavity of the acoustic structure 2031 may be acoustically coupled to the acoustic cavity of the second acoustic structure 2032 via a sound guide channel of the second acoustic structure 2032. The acoustic cavity of the second acoustic structure 2032 may be acoustically coupled to the acoustic cavity of the third acoustic structure 2033 through the sound channel 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 channel of the fifth acoustic structure 2035. The acoustic cavity of the fifth acoustic structure 2035 can be acoustically connected to the acoustic cavity of the sixth acoustic structure 2036 through the sound channel 2061 of the sixth acoustic structure 2036. Acoustic cavity of the third acoustic The acoustic structure 2033 and the acoustic cavity 2062 of the sixth acoustic structure 2036 can be acoustically coupled to the same or to different acoustoelectric transducers. All such modifications fall within the protection scope of the present invention.

In some embodiments, each of the acoustic structures 2030 may adjust the received audio signal to generate a subband audio signal. The generated subrange audio signals can be transmitted to an acoustoelectric transducer acoustically associated with each acoustic structure. Acoustoelectric transducers convert received subrange audio signals into subrange electrical signals. In some embodiments, acoustic structures in acoustic structure 2030 may have different resonant frequencies. In this case, the acoustic structures in the acoustic structure 2030 may generate sub-band audio signals with different resonant frequencies. After conversion by acoustoelectric transducers corresponding to acoustic structures, subrange electrical signals with different resonant frequencies can be formed. In some embodiments, the implementation of the number of acoustic structures 2030 and/or acoustoelectric transducers 2020 may be set in accordance with the actual conditions. For example, the number of acoustic structures 2030 and/or acoustoelectric transducers 2020 may be set according to the number of subband audio signals and/or subband electrical signals to be generated. Just for example, when the number of subband electrical signals to be generated is 6, as shown in FIG. 20, 6 acoustic structures can be installed and the microphone 2000 can create 6 sub-range electrical signals whose resonant frequencies are in the ranges of 500 Hz - 700 Hz, 1000 Hz - 1300 Hz, 1700 Hz - 2200 Hz, 3000 Hz - 3800 Hz, 4700 Hz - 5700 Hz, 7000 Hz - 12000 Hz, respectively. As another example, the resonant frequencies of the 6 sub-band electrical signals generated by the microphone 2000 may be in the range of 500 Hz-640 Hz, 640 Hz-780 Hz, 780 Hz-930 Hz, 940 Hz-1100 Hz, 1100 Hz-1300 Hz and 1300 Hz - 1500 Hz, respectively. As a further example, the resonant frequencies of the 6 sub-band electrical signals output from the microphone 2000 may be in the range of 20 Hz - 120 Hz, 120 Hz - 210 Hz, 210 Hz - 320 Hz, 320 Hz - 410 Hz, 410 Hz - 500 Hz and 500 Hz - 640 Hz, respectively.

In some embodiments, by having one or more acoustic structures in the microphone, for example, acoustic structure 1730 and acoustic structure 1770 in microphone 1700, acoustic structure 1830, acoustic structure 1870 and acoustic structure 1880 in microphone 1800, acoustic structure 1901, acoustic structure 1902, acoustic structure 1903, acoustic structure 1904, acoustic structure 1905, and acoustic structure 1906 in the microphone 1900, the resonant frequency of the microphone can be increased, thereby improving the sensitivity of the microphone over a wider frequency range. Furthermore, by arranging multiple acoustic structures and/or acoustoelectric transducers in various ways, such as where each acoustic structure corresponds to a single acoustoelectric transducer shown in microphone 2000 in FIG. 20, the sensitivity of the microphone 2000 over a wider frequency range can be improved and subband electrical signals can be generated by dividing the frequencies of the audio signal, thus reducing the burden on subsequent hardware processing.

In FIG. 21 is a plot of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 21, the horizontal axis represents the frequency expressed in Hz and the vertical axis represents the frequency response of the microphone expressed in dBV. Taking as an example a microphone containing 11 acoustic structures, the 11 dotted lines in FIG. 21 represent 11 frequency responses of acoustic structures. In some embodiments, the frequency responses of the 11 acoustic structures may span the frequency range (ie, 20 Hz - 20 kHz) audible to the human ear. The solid line in Fig. 21 represents the frequency response of the microphone 2110. For ease of understanding, the graph 2110 of the frequency response of the microphone can be considered as obtained by merging the frequency responses of 11 acoustic designs. In some embodiments, adjusting the target frequency response of the microphone may be achieved by adjusting the frequency response of one or more acoustic structures. For example, since the fundamental frequency of human speech is generally concentrated between about 100 Hz and 300 Hz, and most of the speech information is also concentrated in the middle and low frequency band, provided that the communication result after processing the sub-band signals is not degraded, the number of high-frequency sub-band acoustic signals can be reduced (that is, the number of acoustic structures whose resonant frequencies are in the high frequency band) can be reduced. As another example, at the intersection of the frequency responses (eg, two adjacent frequency responses) of two or more acoustic structures, the frequency response of a microphone formed by fusion may have dips. A dip can be understood as a drop in frequency response (eg, ΔdBV shown in FIG. 21) between an adjacent peak and trough in a merged frequency response (eg, plot 2110). The formation of pits can cause large fluctuations in the frequency response of the microphone, thereby affecting the sensitivity and/or the Q value of the microphone. In some embodiments, the resonant frequency of the acoustic structure can be lowered by adjusting the design parameters of the acoustic structure, 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, by adjusting the design parameters of the acoustic design, such as placing an acoustic impedance component in the microphone, etc., the frequency response bandwidth of the acoustic design can be increased to smooth out larger dips in the frequency range of the frequency response plot 2110 after merging. , thus improving the performance of the microphone. For example, in FIG. 22 is a schematic diagram of the frequency response of an exemplary microphone in accordance with some embodiments of the present invention. As shown in FIG. 22, the horizontal axis represents the frequency expressed in Hz, and the vertical axis represents the frequency response of the microphone expressed in dBV. Each dotted line can represent one of 11 microphone acoustic design frequency response curves, respectively. Compared to the 11 acoustic structures corresponding to these 11 dotted lines in FIG. 21, 11 acoustic structures corresponding to these 11 dotted lines in FIG. 22 may have higher acoustic impedance. For example, the inner surfaces of the side walls of the sound guide channels 11 of the acoustic structures corresponding to these 11 dotted lines in FIG. 22 are relatively coarse, the sonic guide tubes or acoustic cavities have acoustic impedance components, and the sonic guide tubes are relatively small, and the like. Compared to the acoustic design frequency response plot 2110 shown in FIG. 21, acoustic design graph 2210 shown in FIG. 22 (especially the frequency response plot at relatively high frequencies) has a wider bandwidth. The frequency response of the microphone obtained by merging the frequency responses of the 11 acoustic structures has rather small dips (eg, ∆dBV shown in FIG. 22) and the merged frequency response 2210 is flatter.

Having thus described the basic concepts, it should be apparent to those skilled in the art upon reading this detailed invention that the foregoing detailed disclosure is intended to be by way of example only and not limitation. Various changes, improvements and modifications may take place and may be carried out by those skilled in the art, although this is not explicitly stated here. These changes, improvements and modifications are intended to be contemplated by the present invention and are within the spirit and scope of the exemplary embodiments of the present invention.

In addition, regarding the terminology used to describe embodiments of the present invention. For example, the terms “one embodiment,” “an embodiment,” and/or “certain embodiments” mean that a particular function, structure, or feature described in connection with an embodiment of the invention is included in at least one embodiment of the present invention. . Therefore, it is emphasized and should be understood that two or more references to "an embodiment", "one of the embodiments", or "alternative embodiment" in various parts of this specification do not necessarily all refer to the same embodiment of the invention. In addition, specific features, designs, or characteristics may be combined as needed in one or more embodiments of the present invention.

Additionally, those skilled in the art will understand that the approaches of the present invention may be illustrated and described herein in any of a variety of patentable classes or contexts containing any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof.

In addition, the described order of processing elements or sequence, or the use of numbers, letters or other designations, is not intended to limit the claimed processes and methods in any order, except as may be claimed in the claims. While the above disclosure discusses through various examples what is currently considered to be a variety of useful embodiments of the invention, it should be understood that such details are provided for this purpose only and the claims are not limited to the disclosed embodiments of the invention, but rather are intended to cover modifications and equivalent constructions that fall within the spirit and scope of the disclosed embodiments of the invention. For example, while the implementation of the various components described above may be implemented on a device, it may also be implemented as a software-only solution—eg, installation on an existing server or on a mobile device.

Likewise, it should be understood that in the foregoing description of embodiments of the present invention, various features are sometimes grouped into a single embodiment, drawing, or description thereof for the purpose of streamlining the disclosure and assisting in understanding one or more of the various embodiments. However, this mode of disclosure should not be interpreted as reflecting the intent that the claimed subject matter of the present invention requires more features than are expressly mentioned in each claim. In fact, the claimed subject matter of the present invention may contain fewer features than the total number of features of the single embodiment disclosed above.

In some embodiments of the invention, numbers expressing quantities of ingredients, properties, etc., used to describe and claim some embodiments of the invention, should be understood as being modified in some cases by the term "about", "approximately" or "substantially" and etc. Unless otherwise noted, “about”, “approximately”, or “substantially” may indicate a change within ±20% of the value being described. Accordingly, in some embodiments, the numerical data given in the description and the appended claims are approximations that may vary depending on the properties that are desired to be obtained by a particular embodiment. In some embodiments, the implementation of the numeric data must take into account the specified significant digits and use the algorithms used for ordinary digits. Although the ranges of numbers and data used to illustrate the broad scope of application of some embodiments of the present invention are approximations, the numerical values in specific examples may be as accurate as practical.

Claims (33)

1. Microphone containing at least one acoustoelectric transducer configured to convert an audio signal into an electrical signal; And an acoustic structure that includes a sound guide channel and an acoustic cavity, wherein the acoustic cavity is acoustically connected to said at least one acoustoelectric transducer and is acoustically connected to the external environment of the microphone through the sound guide channel, wherein the acoustic structure has a first resonant frequency, said at least one acoustoelectric transducer has a second resonant frequency, and the absolute value of the difference between the first resonant frequency and the second resonant frequency is at least 100 Hz. 2. Microphone according to claim 1, further comprising a housing in which said at least one acoustoelectric transducer and an acoustic cavity are located, and the housing contains a first side wall for forming said acoustic cavity, wherein the first end of the sound guide channel is located on the first side wall, and the second end of the sound guide channel is remote from the first side wall and is located outside the housing. 3. The microphone according to claim. 1, which further comprises a housing in which said at least one acoustoelectric transducer and an acoustic cavity are located, and the housing contains a first side wall for forming said acoustic cavity, wherein the first end of the sound guide channel is located on the first side wall, and the second end of the sound guide channel is removed from the first side wall and passes into the acoustic cavity. 4. The microphone according to claim 1, which further comprises a housing in which said at least one acoustoelectric transducer and an acoustic cavity are located, and the housing contains a first side wall for forming said acoustic cavity, wherein the first end of the guiding sound channel is removed from the first side wall and is located outside the housing, and the second end of the guiding sound channel passes into the acoustic cavity. 5. The microphone according to claim. 1, in which the side wall of the guide sound channel forms an angle of inclination with the Central axis of the guide sound channel, and the value of the angle of inclination is from 0° to 20°. 6. The microphone according to claim. 1, in which in the directing sound channel or in the acoustic cavity there is a component with acoustic resistance, while the component with acoustic resistance is configured to control the bandwidth of the acoustic structure, and the value of the acoustic resistance of the component with acoustic resistance is from 1 to 100 Pa⋅s/m. 7. The microphone according to claim. 1, in which the diameter of the guide sound channel does not exceed twice the length of the guide sound channel, the diameter of the guide sound channel is from 0.1 to 10 mm, and the length of the guide sound channel is from 1 to 8 mm. 8. The microphone according to claim 1, in which the roughness of the inner surface of the side wall forming the sound guide channel does not exceed 0.8, the inner diameter of the acoustic cavity is not less than the thickness of the acoustic cavity, the inner diameter of the acoustic cavity is from 1 to 20 mm, and the thickness of the acoustic cavity is from 1 to 20 mm. 9. Microphone according to claim 1, further comprising a second acoustic structure comprising a second sound guide channel and a second acoustic cavity, wherein the second acoustic cavity is acoustically connected to the external environment of the microphone through the second sound guide channel, wherein the second acoustic structure has a third resonant frequency which is different from the first resonant frequency. 10. Microphone according to any one of paragraphs. 1-9, additionally containing a third acoustic structure containing a third guiding sound channel, a fourth guiding sound channel and a third acoustic cavity, wherein the acoustic cavity is acoustically connected to the third acoustic cavity through the third guiding sound channel, the second acoustic cavity is acoustically connected to the external environment of the microphone through the second sound guide channel and is acoustically connected to the third acoustic cavity through the fourth sound guide channel, the third acoustic cavity is acoustically connected to said at least one acoustoelectric transducer, and the third acoustic structure has a fourth resonant frequency that is different from the third resonant frequency and the first resonant frequency. 11. Microphone containing at least one acoustoelectric transducer configured to convert an audio signal into an electrical signal; And the first acoustic structure and the second acoustic structure, wherein the first acoustic structure contains the first guiding sound channel and the first acoustic cavity, the second acoustic structure contains the second guiding sound channel and the second acoustic cavity, wherein the first directing sound channel is acoustically connected to the external environment of the microphone, the first acoustic cavity is connected to the second acoustic cavity through the second sound guide channel, and the second acoustic cavity is acoustically connected to said at least one acoustoelectric transducer, the first acoustic structure has the first resonant frequency, the second acoustic structure has a second resonant frequency, and the first resonant frequency and the second resonant frequency are different.

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