Bone conduction pickup earphone

Abstract

The utility model discloses a bone conduction pickup earphone. The bone conduction pickup earphone comprises an air conduction microphone which is a microphone which picks up a voice signal through an air path, and an air conduction microphone which picks up a voice signal through an air path, the air conduction filter circuit is used for filtering the air conduction voice signal picked up by the air conduction microphone and outputting the filtered air conduction voice signal; the bone conduction microphone is a microphone which is used for picking up a voice signal of vibration of a specified part; the bone conduction filter circuit is used for filtering the bone conduction voice signal picked up by the bone conduction microphone and outputting the filtered bone conduction voice signal; the signal mixing circuit is used for carrying out signal mixing processing on the filtered air conduction voice signal and the filtered bone conduction voice signal and outputting a mixed voice signal; and the earphone interface is used for outputting the mixed voice signal to a connected device to which the bone conduction pickup earphone is connected.

Description

Technical Field

[0001] The present application relates to the technical field of wired headphones, and in particular to a bone conduction sound pickup headphone. Background Art

[0002] Bone conduction microphones transmit sound by picking up the vibrations of the skull during speech. Because bone conduction microphones require no openings, they effectively suppress wind and ambient noise. However, bone conduction microphones can lose some syllables and high-frequency signals, meaning that the weaker skull vibrations during speech are lost.

[0003] In the field of intercom accessories, there are also bone conduction pickup earphones, which use methods such as throat vibration bone conduction pickup and head vibration bone conduction pickup. However, due to the poor performance of the device itself, and the differences in head shape and wearing position among users, the bone conduction pickup effect varies, resulting in poor bone conduction pickup performance and a reduced user experience. Utility Model Content

[0004] The embodiment of the present application provides a bone conduction sound pickup earphone to at least solve the technical problem of poor bone conduction sound pickup performance of bone conduction sound pickup earphones in the related art.

[0005] According to one aspect of an embodiment of the present application, a bone conduction sound pickup headset is provided, comprising: an air conduction microphone, wherein the air conduction microphone is a microphone that picks up voice signals through an air path; an air conduction filter circuit, configured to filter the air conduction voice signal picked up by the air conduction microphone and output the filtered air conduction voice signal; a bone conduction microphone, wherein the bone conduction microphone is a microphone that picks up voice signals vibrating at a specified part; a bone conduction filter circuit, configured to filter the bone conduction voice signal picked up by the bone conduction microphone and output the filtered bone conduction voice signal; a signal mixing circuit, configured to mix the filtered air conduction voice signal and the filtered bone conduction voice signal and output a mixed voice signal; and a headphone interface, configured to output the mixed voice signal to a connected device to which the bone conduction sound pickup headset is connected.

[0006] In some exemplary embodiments, the bone conduction pickup earphones further include: a noise reduction switch for selecting a gear used by the bone conduction pickup earphones from a plurality of gears; wherein the air conduction filter circuit includes a plurality of high-pass filter circuits, and the bone conduction filter circuit includes a plurality of low-pass filter circuits, and the high-pass filter circuits in the plurality of high-pass filter circuits and the low-pass filter circuits in the plurality of low-pass filter circuits form a plurality of filter circuit pairs, and each filter circuit in the plurality of filter circuit pairs corresponds to one of the plurality of gears.

[0007] In some exemplary embodiments, the multiple high-pass filtering circuits are multiple RC high-pass filtering circuits connected in parallel, and each of the multiple RC high-pass filtering circuits includes a resistor and a capacitor connected in series; the multiple low-pass filtering circuits are multiple RC low-pass filtering circuits, and each of the multiple RC low-pass filtering circuits includes a resistor and a capacitor, the resistors of different RC low-pass filtering circuits in the multiple RC low-pass filtering circuits are connected in parallel, and the capacitors in the multiple RC low-pass filtering circuits are the same capacitor. In the multiple RC low-pass filtering circuits, the rear ends of the multiple resistors connected in parallel are grounded via the capacitors and connected to the input end of the signal mixing circuit.

[0008] In some exemplary embodiments, the multiple gears include a pure air conduction gear. When the noise reduction switch selects the pure air conduction gear, the air conduction voice signal is directly output to the headphone interface, the connection between the bone conduction microphone and the bone conduction filter circuit is disconnected, and the connection between the air conduction microphone and the air conduction filter circuit is disconnected.

[0009] In some exemplary embodiments, the bone conduction pickup earphone further includes: a control component for detecting ambient noise and switching the gear position of the noise reduction switch based on the intensity of the detected ambient noise.

[0010] In some exemplary embodiments, the control component is connected to the air conduction microphone, and the ambient noise is detected from the air conduction voice signal.

[0011] In some exemplary embodiments, the multiple gears also include a first noise reduction gear and a second noise reduction gear, the first noise reduction gear corresponds to the first filter circuit pair among the multiple filter circuit pairs, the second noise reduction gear corresponds to the second filter circuit pair among the multiple filter circuit pairs, the filtering frequency division point of the first filter circuit pair is smaller than the filtering frequency division point of the second filter circuit pair, the intensity of the ambient noise corresponding to the pure air conduction gear is smaller than the intensity of the ambient noise corresponding to the first noise reduction gear, and the intensity of the ambient noise corresponding to the first noise reduction gear is smaller than the intensity of the ambient noise corresponding to the second noise reduction gear.

[0012] In some exemplary embodiments, the signal mixing circuit includes: a first adjustable resistor, a second adjustable resistor, a third adjustable resistor, and an operational amplifier, wherein the first adjustable resistor and the second adjustable resistor are used to adjust the input ratio of the filtered air conduction voice signal and the filtered bone conduction voice signal, wherein a front end of the first adjustable resistor is connected to the output end of the air conduction filter circuit, and a rear end of the first adjustable resistor is connected to the first input end of the operational amplifier, a front end of the second adjustable resistor is connected to the output end of the bone conduction filter circuit, and a rear end of the second adjustable resistor is connected to the first input end of the operational amplifier; the third adjustable resistor is used to adjust the amplification gain after signal mixing, wherein the third adjustable resistor is connected between the first input end and the output end of the operational amplifier; the operational amplifier is used to amplify the voice signal input from the first input end of the operational amplifier, and wherein the second input end of the operational amplifier is grounded.

[0013] In some exemplary embodiments, the bone conduction pickup earphone further includes: a first adjustment component for adjusting the resistance of at least one of the first adjustable resistor and the second adjustable resistor; and a second adjustment component for adjusting the resistance of the third adjustable resistor; wherein the first adjustment component and the second adjustment component are the same component or different components.

[0014] In some exemplary embodiments, the bone conduction pickup headset further includes: a PTT button and a speaker.

[0015] In an embodiment of the present application, a bone conduction microphone and a bone conduction microphone are used in combination, and the bone conduction pickup earphone includes: an air conduction microphone, wherein the air conduction microphone is a microphone that picks up voice signals through an air path; an air conduction filter circuit, which is used to filter the air conduction voice signals picked up by the air conduction microphone and output the filtered air conduction voice signals; a bone conduction microphone, wherein the bone conduction microphone is a microphone that picks up voice signals vibrating at a specified part; a bone conduction filter circuit, which is used to filter the bone conduction voice signals picked up by the bone conduction microphone and output the filtered bone conduction voice signals; and a signal mixing circuit, which is used to mix the filtered air conduction voice signals and the filtered bone conduction voice signals. And output a mixed voice signal; a headphone interface is used to output the mixed voice signal to the connected device to which the wired headphones are connected. Since the air conduction microphone and the bone conduction microphone are used to pick up the sound respectively and filter the sound respectively, after removing the noise and unnecessary frequency components in the corresponding voice signal, the filtered voice signal is mixed. The advantages of the air conduction microphone signal and the bone conduction microphone signal can be combined, and the air conduction microphone signal can be used to compensate for the influence of the differences in head shape, wearing position, etc. of different users on bone conduction sound pickup. The technical effect of improving the bone conduction sound pickup performance and enhancing the user experience can be achieved, thereby solving the technical problem of poor bone conduction sound pickup performance of the bone conduction sound pickup headphones in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 1 is a schematic structural diagram of an optional bone conduction pickup earphone according to an embodiment of the present application;

[0018] Figure 2 is a schematic structural diagram of another optional bone conduction pickup earphone according to an embodiment of the present application;

[0019] Figure 3 is a schematic structural diagram of an optional high-pass filter circuit and a low-pass filter circuit according to an embodiment of the present application;

[0020] Figure 4 1 is a schematic structural diagram of another optional bone conduction pickup earphone according to an embodiment of the present application;

[0021] Figure 5 1 is a schematic structural diagram of another optional bone conduction pickup earphone according to an embodiment of the present application;

[0022] Figure 61 is a schematic structural diagram of another optional bone conduction pickup earphone according to an embodiment of the present application;

[0023] Figure 7 This is a schematic diagram of an optional process of switching the noise reduction switch gear according to an embodiment of the present application;

[0024] Figure 8 is a schematic structural diagram of an optional signal mixing circuit according to an embodiment of the present application;

[0025] Figure 9 is a schematic structural diagram of another optional signal mixing circuit according to an embodiment of the present application;

[0026] Figure 10 This is a structural diagram of another optional bone conduction pickup earphone according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] A bone conduction pickup headset is provided in an embodiment of the present application. The bone conduction pickup headset is a wired headset, which includes a bone conduction microphone. The bone conduction microphone transmits sound by picking up vibration signals from the skull or other parts when speaking. Since the bone conduction microphone does not require holes, it has a strong suppressive effect on wind noise and environmental noise. However, the bone conduction microphone will lose some syllables and high-frequency signals, that is, signals with weak vibration sensations in parts such as the skull will be lost when speaking. In the field of intercom accessories, there are also wired headsets with bone conduction microphones, which are generally pure bone conduction microphones for sound pickup. Common sound testing methods include throat vibration bone conduction pickup, head vibration bone conduction pickup, etc. However, due to the poor performance of the device itself, and the differences in head shape, wearing position, etc. of different users, the bone conduction pickup effect will be different, resulting in a poor user experience.

[0030] To this end, a bone conduction microphone can be used in combination with an air conduction microphone (a microphone that picks up sound through an air path), and then a special bone conduction noise reduction algorithm can be used to achieve its hybrid application. The noise reduction algorithm is generally built-in to the TWS (TrueWireless Stereo) Bluetooth chip or imported by a third party, and the corresponding headphones are TWS Bluetooth headphones. The above solution is generally a TWS Bluetooth headset with bone conduction microphone noise reduction: the bone conduction microphone is used in combination with a single or multiple air conduction microphones to pick up sound at the same time, and the collected bone conduction microphone signal and the air conduction microphone signal are processed by a special bone conduction noise reduction algorithm, and finally a clear pickup effect is output. However, due to the need to use expensive TWS Bluetooth chips and special bone conduction noise reduction algorithms, the cost of TWS Bluetooth headsets is high.

[0031] Alternatively, a wired headset with both a bone conduction microphone and an air conduction microphone can be used. A hardware switch can be used to select which microphone to use, allowing for different application environments. However, only one microphone can be active at a time. However, even with this solution, the bone conduction microphone still suffers from syllable dropouts, affecting sound pickup performance and reducing the user experience.

[0032] For any of the above solutions, the bone conduction microphone relies on vibration to pick up voice signals. Due to the different head shapes and wearing positions of different users, that is, the fit of the bone conduction microphone will be different, and the bone conduction pickup effect will also be different. The bone conduction pickup effect of poorly fitted microphones will also be correspondingly poor, thereby reducing the user experience.

[0033] In order to at least partially solve the above technical problems, in this embodiment, the air conduction microphone signal and the bone conduction microphone signal are mixed through a simple hardware circuit or integrated circuit, and finally mixed into a voice signal to be output to the connected device (for example, a walkie-talkie terminal) to which the wired headset is connected, without the need to add a TWS Bluetooth chip and a dedicated bone conduction noise reduction algorithm and its complicated development and debugging work. The noise reduction algorithm of the connected device such as the walkie-talkie terminal can be used, and the mixed use of the bone conduction microphone and the air conduction microphone on the wired headset is realized, which has the advantages of low cost and good sound pickup performance.

[0034] Figure 1 FIG. 1 is a schematic structural diagram of an optional bone conduction pickup earphone according to an embodiment of the present application. Figure 1 As shown, the bone conduction pickup earphone includes: an air conduction microphone 101, an air conduction filter circuit 102, a bone conduction microphone 103, a bone conduction filter circuit 104, a signal mixing circuit 105, and an earphone interface 106.

[0035] The air conduction microphone 101 is a microphone that picks up voice signals through an air path. The picked-up voice signals are air-conducted voice signals. There can be one or more air conduction microphones 101. The air-conduction voice signals can compensate for the lack of high-frequency signals in the bone conduction microphone 103. The air conduction filter circuit 102 can be used to filter the air-conduction voice signals picked up by the air conduction microphone 101 and output the filtered air-conduction voice signals. Here, the air conduction filter circuit 102 can include one or more high-pass filter circuits to filter out low-frequency signals from the air-conduction voice signals picked up by the air conduction microphone 101.

[0036] Bone conduction microphone 103 is a microphone used to pick up voice signals from vibrations in a designated area, and has a strong suppressive effect on external environmental noise and wind noise. The designated area can be the skull, the larynx, or other part of the human body that a bone conduction headset can fit snugly. Taking the skull as an example, bone conduction microphone 103 can fit snugly against the skull to pick up voice signals from skull vibrations when a person speaks. Bone conduction filter circuit 104 can filter the bone conduction voice signals picked up by bone conduction microphone 103 and output the filtered bone conduction voice signals. Bone conduction filter circuit 104 can include one or more low-pass filter circuits to remove high-frequency signals from the bone conduction voice signals picked up by air conduction microphone 103.

[0037] The signal mixing circuit 105 is used to mix the filtered air conduction speech signal and the filtered bone conduction speech signal and output a mixed speech signal. Here, the signal mixing circuit 105 can be a hardware circuit or an integrated circuit, and may include components such as an OPA (operational amplifier) and a mixer for mixing high-frequency and low-frequency signals. The signal mixing circuit 105 can also perform other signal processing on the input speech signal, such as gain adaptation and signal amplification.

[0038] The headphone jack 106 is used to output the mixed voice signal to the connected device to which the wired headset is connected. The connected device here can be a walkie-talkie terminal, a mobile phone, a computer, a tablet computer, an audio system, a television, or other devices that allow wired headsets to be inserted. It should be noted that the headphone jack 106 has the function of outputting the mixed voice signal to the connected device to which the wired headset is connected, and it can be used to connect a bone conduction pickup headset to the connected device. The bone conduction pickup headset can be an accessory for a walkie-talkie headset, and can also be adapted to other devices with a headphone jack. When it is used as an accessory for a walkie-talkie, it can solve the problem of poor bone conduction pickup effect that exists in walkie-talkie headset accessories. For other connected devices, the same or similar problems that exist in other connected devices can also be solved.

[0039] According to this embodiment, the bone conduction sound pickup headset includes: an air conduction microphone, wherein the air conduction microphone is a microphone that picks up voice signals through an air path; an air conduction filter circuit, which is used to filter the air conduction voice signal picked up by the air conduction microphone and output the filtered air conduction voice signal; a bone conduction microphone, wherein the bone conduction microphone is a microphone that picks up voice signals of vibrations of a specified part; a bone conduction filter circuit, which is used to filter the bone conduction voice signal picked up by the bone conduction microphone and output the filtered bone conduction voice signal; a signal mixing circuit, which is used to mix the filtered air conduction voice signal and the filtered bone conduction voice signal and output the mixed voice signal; and a headphone interface, which is used to output the mixed voice signal to a connected device to which the wired headset is connected. This solves the technical problem of poor bone conduction sound pickup performance of bone conduction sound pickup headsets in the related art, improves the bone conduction sound pickup performance, and enhances the user experience.

[0040] In some exemplary embodiments, bone conduction headphones can use the same voice signal processing method for different noise environments (e.g., loud ambient noise, quieter environments, etc.), that is, without distinguishing between noise reduction levels. In this case, the output ratio of air conduction voice signals and bone conduction voice signals is fixed, and it cannot adapt to different noise scenarios.

[0041] In this embodiment, if Figure 2As shown, the bone conduction pickup earphones also include a noise reduction switch 201 for selecting the gear used by the wired earphones from a plurality of gears. The air conduction filter circuit 102 includes a plurality of high-pass filter circuits 202, and the bone conduction filter circuit 104 includes a plurality of low-pass filter circuits 203. The number of high-pass filter circuits in the plurality of high-pass filter circuits is the same as the number of low-pass filter circuits in the plurality of low-pass filter circuits, and they correspond one-to-one. The high-pass filter circuits in the plurality of high-pass filter circuits and the low-pass filter circuits in the plurality of low-pass filter circuits form a plurality of filter circuit pairs. Each filter circuit in the plurality of filter circuit pairs corresponds to one of the plurality of gears (the gear corresponding to the filter circuit pair can be a noise reduction gear, which has a certain ability to reduce ambient noise). The number of gears included in the plurality of gears is greater than or equal to the number of filter circuit pairs included in the plurality of filter circuit pairs. Different filter circuit pairs in the plurality of filter circuit pairs can correspond to different filter crossover points.

[0042] It should be noted that for a filter circuit pair, the corresponding filter crossover frequency point can be understood as follows: in the voice signal input to the low-pass filter circuit in the filter circuit pair, signals above the filter crossover frequency point are attenuated, and in the voice signal input to the high-pass filter circuit in the filter circuit pair, signals below the filter crossover frequency point are attenuated. The filter crossover frequency point can adjust the proportion of the two voice signals (air conduction voice signal and bone conduction voice signal) input to the signal mixing circuit 105, thereby adjusting the voice signal that plays a dominant role in the two voice signals. When the ambient noise is weak, the signal quality of the air conduction voice signal is better (richer high-frequency signals), and when the ambient noise is strong, the bone conduction voice signal has stronger anti-interference ability. Therefore, the filter circuit pair used can be selected by the noise reduction switch 201 to adapt to different noise environments.

[0043] For example, for a certain gear, the filter crossover point is set near 800Hz, the signal above 800Hz in the bone conduction microphone signal (i.e., bone conduction voice signal) is attenuated, and the signal below 800Hz in the air conduction microphone signal (i.e., air conduction voice signal) is attenuated, and the air conduction microphone signal is the main signal.

[0044] For another example, for another gear, the filter crossover point is set at around 2500 Hz, the signal above 2500 Hz in the bone conduction microphone signal is attenuated, the signal below 2500 Hz in the air conduction microphone signal is attenuated, and the bone conduction microphone signal is the main signal.

[0045] Through this embodiment, by setting a noise reduction switch combined with a high-pass filter circuit and a low-pass filter circuit to switch the bone conduction microphone hybrid solution, the headphone pickup effect can be improved and the user experience can be enhanced.

[0046] In some exemplary embodiments, in order to improve the convenience of implementing the filter circuit, the high-pass filter circuit 202 can be implemented by an RC high-pass filter circuit, and the low-pass filter circuit 203 can be implemented by an RC low-pass filter circuit. Correspondingly, the multiple high-pass filter circuits 202 can be multiple RC high-pass filter circuits, and each RC high-pass filter circuit includes a resistor and a capacitor connected in series. The multiple low-pass filter circuits can be multiple RC low-pass filter circuits connected in parallel, each RC low-pass filter circuit includes a resistor and a capacitor, the resistors of different RC low-pass filter circuits are connected in parallel, the capacitors in the multiple RC low-pass filter circuits are the same capacitor, and in the multiple RC low-pass filter circuits, the rear ends of the multiple resistors in parallel are grounded via the above-mentioned capacitors and are connected to the input end of the signal mixing circuit 105.

[0047] It should be noted that because the RC high-pass filter circuit and the RC low-pass filter circuit are combined into a filter circuit pair, different filter circuit pairs have different filter crossover frequency points. Therefore, the resistance values of the resistors and the capacitance values of the capacitors included in different RC high-pass filter circuits are at least partially different. Similarly, the resistance values of the resistors included in different RC low-pass filter circuits are different.

[0048] For example, Figure 3 As shown, the high-pass filter circuit 202 is an RC high-pass filter circuit composed of a resistor and a capacitor connected in series, and the low-pass filter circuit 204 includes a resistor and a capacitor. The resistors of different low-pass filter circuits 204 are connected in parallel, and the capacitors of different low-pass filter circuits 204 are the same capacitor.

[0049] According to this embodiment, the air conduction filter circuit is realized by using the RC high-pass filter circuit and the RC low-pass filter circuit, which can improve the convenience of realizing the filter circuit.

[0050] In some exemplary embodiments, in addition to the gear positions corresponding to the filter circuit, the multiple gear positions may also include a pure air conduction gear position. When the noise reduction switch selects the pure air conduction gear position, the air conduction voice signal is directly output to the headphone interface, the connection between the bone conduction microphone and the bone conduction filter circuit is disconnected, and the connection between the air conduction microphone and the air conduction filter circuit is disconnected.

[0051] For example, Figure 4 As shown, one position of the noise reduction switch 201 may correspond to a pure air conduction mode, in which case the bone conduction microphone does not work, which is consistent with the traditional air conduction microphone solution.

[0052] Through this embodiment, by setting the pure air conduction gear, the complexity of signal processing can be reduced while ensuring the quality of the voice signal in an adaptive environment (for example, a relatively quiet environment).

[0053] In some exemplary embodiments, the noise reduction switch 201 may be a toggle switch that allows the user to manually toggle. In this case, the user can manually adjust the gear position of the noise reduction switch 201 as needed. In this way, the noise reduction effect is switched through the hardware gear position, which is convenient, stable and reliable.

[0054] Optionally, the noise reduction switch 201 can adopt a software intelligent control solution, which automatically detects the ambient noise and automatically switches the gear of the noise reduction switch 201 according to environmental requirements. It also correspondingly switches the mixed solution of air conduction voice signals and bone conduction voice signals or the solution of using air conduction voice signals alone. This can improve the intelligence level of the noise reduction switch control, eliminate the need for user participation, and make it more convenient to use.

[0055] In this embodiment, if Figure 5 As shown, the bone conduction pickup earphones also include a control component 501, which is connected to the noise reduction switch 201, and is used to detect ambient noise and switch the gear of the noise reduction switch based on the intensity of the detected ambient noise. The control component 501 controls the gear switching of the noise reduction switch 201 through GPIO (General-purpose input / output). Different gears can correspond to different GPIOs, or one GPIO can be used to control the noise reduction switch 201. The noise reduction switch 201 can have a signal processing function, which can parse the control signal transmitted through the GPIO and switch the corresponding gear based on the control signal.

[0056] Here, the control component 501 can have a noise detection function, or it can be a voice signal collected from a separate detection microphone (which can be a microphone that picks up voice signals through an air path). The detection microphone and the aforementioned air conduction microphone 101 can be located at different positions of the bone conduction pickup earphones. Optionally, the control component 501 can be connected to the air conduction microphone 101, and the ambient noise is detected from the air conduction voice signal. In the above manner, there is no need to set up a separate detection microphone, and detecting the ambient noise from the air conduction voice signal can better reflect the noise situation around the sound source, thereby improving the rationality of gear switching.

[0057] Through this embodiment, the gear position of the noise reduction switch is switched based on the intensity control of the ambient noise, which can improve the intelligence level of the noise reduction switch and improve the convenience of controlling the noise reduction switch.

[0058] In some exemplary embodiments, similar to the aforementioned embodiments, the size of the filter crossover frequency of the filter circuit pair is positively correlated with the proportion of bone-conducted voice signals, and the corresponding higher noise reduction level. To improve the convenience of noise reduction switch control, at least two noise reduction gears can be set, namely, a first noise reduction gear and a second noise reduction gear. The first noise reduction gear corresponds to the first filter circuit pair among the multiple filter circuit pairs, and the second noise reduction gear corresponds to the second filter circuit pair among the multiple filter circuit pairs. The filter crossover frequency of the first filter circuit pair is lower than the filter crossover frequency of the second filter circuit pair.

[0059] Because the filtering crossover frequency of the first filter circuit pair is lower than that of the second filter circuit pair, the noise reduction level corresponding to the first filter circuit pair is lower than that corresponding to the second filter circuit pair, and the noise intensity adapted to the first noise reduction level is lower than that adapted to the second noise reduction level. To this end, the intensity of the ambient noise corresponding to the pure air conduction level can be set to be lower than the intensity of the ambient noise corresponding to the first noise reduction level, and the intensity of the ambient noise corresponding to the first noise reduction level can be set to be lower than the intensity of the noise corresponding to the second noise reduction level.

[0060] For example, Figure 6 As shown, the main adjustable parameters of air conduction filter circuit 102 are resistors R1 and R2, and capacitors C1 and C2. Two paths are configured to meet different filtering frequency requirements, and the corresponding path is switched according to the position of noise reduction switch 201. The main adjustable parameters of bone conduction filter circuit 104 are resistors R3 and R4, and capacitor C3. Two paths are configured to meet different filtering frequency requirements, and the corresponding path is switched according to the position of noise reduction switch 201.

[0061] The noise reduction switch 201 has three settings, which can be switched according to different needs in different environments. Position 1 is pure air conduction mode (i.e., the pure air conduction mode), in which the bone conduction microphone is inoperative, consistent with traditional air conduction microphone solutions. Position 2 is level 1 noise reduction (i.e., the first noise reduction mode). By setting the values of the filter circuit's main parameters R1, C1, R3, and C3, the filter crossover frequency is set to around 800Hz. Signals above 800Hz from the bone conduction microphone are attenuated, while signals below 800Hz from the air conduction microphone are attenuated, with the air conduction microphone signal being the primary signal. Position 3 is level 2 noise reduction (i.e., the second noise reduction mode). By setting the values of the filter circuit's main parameters R2, C2, and R4, C3, the filter crossover frequency is set to around 2500Hz. Signals above 2500Hz from the bone conduction microphone are attenuated, while signals below 2500Hz from the air conduction microphone are attenuated, with the bone conduction microphone signal being the primary signal.

[0062] The noise reduction switch 201 can be controlled by software intelligence: detecting the intensity of the ambient noise of the microphone signal and controlling the switching of the noise reduction switch through GPIO. Figure 7As shown, the switching logic of the noise reduction switch 201 may be:

[0063] The default is gear 1, that is, the air conduction microphone is passed through, the flag Flag is set to 1, and the microphone noise signal amplitude Y is detected at a certain frequency;

[0064] When Y is greater than the preset threshold value B and less than the preset threshold value C, it indicates that there is a certain amount of wind noise or other environmental noise, and the noise reduction switch 201 is switched to gear 2 and the flag Flag=2 is set. Otherwise, the Y value continues to be detected;

[0065] When Y is greater than the preset threshold value D, it indicates that the environment is relatively noisy, and the noise reduction switch 201 is switched to gear 3 and the flag Flag=3 is set. Otherwise, the Y value is continuously detected.

[0066] When Y is less than the preset threshold value A, it means that a relatively quiet environment has been reached, and the default gear position 1 is switched back, Flag = 1;

[0067] Among them, A<B<C<D, and there is a certain difference space to avoid frequent switching of channels.

[0068] It should be noted that when the Y value is detected at a certain frequency, a judgment can be performed each time the Y value is detected. For example, first determine whether Y is greater than the preset threshold value B and less than the preset threshold value C, then determine whether Y is greater than the preset threshold value D, and then determine whether Y is less than the preset threshold value A. It can also be possible to execute three judgment logics in sequence, or other control methods, as long as the gear switching of the noise reduction switch 201 can be achieved based on the intensity of the detected ambient noise.

[0069] In actual use, in a quieter environment, the noise reduction switch 201 is switched to gear 1 or gear 2 for use. In a noisy environment (for example, subways, markets, etc.) or a windy environment (for example, ports, Gobi Desert, etc.), the noise reduction switch 201 can be switched to gear 3 for use, which has a better noise reduction effect.

[0070] Through this embodiment, by setting at least two noise reduction gears to adapt to different noise environments, the convenience of controlling the noise reduction switch can be improved.

[0071] In some exemplary embodiments, the signal mixing circuit 105 can perform gain adaptation, amplification, and mixing on the input voice signal. Figure 8As shown, the signal mixing circuit 105 may include a first adjustable resistor 1051, a second adjustable resistor 1052, a third adjustable resistor 1053, and an operational amplifier 1054. The first and second adjustable resistors 1051 are used to adjust the input ratio of the filtered air conduction speech signal and the filtered bone conduction speech signal. The first adjustable resistor 1051 has its front end connected to the output of the air conduction filter circuit 102 and its back end connected to the first input of the operational amplifier 1054 (which may be the negative input or the non-inverting input of the operational amplifier 1054). The second adjustable resistor 1052 has its front end connected to the output of the bone conduction filter circuit 104 and its back end connected to the first input of the operational amplifier 1054. The third adjustable resistor 1053 can be used to adjust the amplification gain after signal mixing and may be an adjustable gain resistor. The third adjustable resistor 1053 is connected between the first input and output of the operational amplifier 1054. The operational amplifier 1054 is configured to amplify a voice signal input from a first input terminal of the operational amplifier 1054 . A second input terminal of the operational amplifier 1054 is grounded.

[0072] For example, Figure 9 As shown, signal mixing circuit 105 is used to mix the bone conduction microphone signal and the air conduction microphone signal. Signal mixing circuit 105 is implemented using an operational amplifier (OPA). The main adjustment parameters are adjustable resistors R5 and R6, and adjustable gain resistor R7. R5 and R6 can adjust the input ratio of the air conduction microphone signal and the bone conduction microphone signal, and R7 can adjust the amplification gain of the mixed signals.

[0073] Through this embodiment, an operational amplifier is used to implement a signal mixing circuit, and three adjustable resistors are used to adjust the input ratio of different voice signals and the amplification gain after signal mixing, thereby improving the flexibility of voice signal mixing.

[0074] In some exemplary embodiments, the bone conduction pickup earphone further includes: a first adjustment component for adjusting the resistance of at least one of the first and second adjustable resistors; and a second adjustment component for adjusting the resistance of the third adjustable resistor. By adjusting the resistance of at least one of the first and second adjustable resistors using the first adjustment component, the input ratio of the air conduction microphone signal and the bone conduction microphone signal can be adjusted, while by adjusting the resistance of the third adjustable resistor using the second adjustment component, the amplification gain after the signals are mixed can be adjusted. The first and second adjustment components can be the same component or different components.

[0075] Here, the first adjustment component and the second adjustment component can be manually adjustable components, such as paddles, buttons, and the like. The size of the vibration signal sensed by the bone conduction microphone varies from person to person. Some users do not wear headphones well enough, and the bone conduction microphone senses a weak signal, resulting in a poor experience. By adding a gain adjustment function, by adjusting the resistance of the adjustable resistors (for example, R5, R6, R7) in the signal mixing circuit, a better sound pickup effect can be achieved to match the use of more users. The adjustment here can be performed manually by the user, so the user can adjust to the optimal sound pickup position according to his or her own auditory perception.

[0076] Through this embodiment, the bone conduction microphone gain is adjustable through a hardware solution, which can solve the problem of weak bone conduction microphone signal caused by poor wearing fit for some users and improve the microphone's sound pickup effect.

[0077] In some exemplary embodiments, the bone conduction pickup headset further includes a PTT (Press To Talk, i.e., press the button first when speaking on a walkie-talkie) button and a speaker.

[0078] Optionally, the bone conduction pickup headset may also include a headphone jack 106, which is an interface for connecting the headset to a connected device (e.g., an intercom terminal). The interface signal may include, but is not limited to, all or part of the following signals: microphone signal, speaker signal, PTT signal, power supply, communication GPIO, etc. The power supply signal can serve as the power source for the bone conduction microphone and OPA. The above solution can be applied to intercom wired headsets with power output, and its use is compatible with existing wired headsets, without any changes to the intercom terminal.

[0079] According to this embodiment, the PTT signal and the speaker signal are transmitted through the earphone interface, which can be compatible with the original wired earphones and improve the compatibility of wired earphones.

[0080] The bone conduction pickup headset in this embodiment is explained below with reference to an optional example. The wired headset in this optional example can be a wired walkie-talkie headset, which is a headset that can implement a hybrid application of a bone conduction microphone and an air conduction microphone in a wired headset. It can be used in walkie-talkie headset accessories with a power output, or it can use a separate battery in walkie-talkie headset accessories without a power output.

[0081] like Figure 10As shown, the bone conduction headset includes an air conduction microphone 101, a bone conduction microphone 103, a noise reduction switch 201, an air conduction filter circuit 102, a bone conduction filter circuit 104, a signal mixing circuit 105, and a headphone jack 106. It may also include a speaker and a PTT button. The air conduction microphone signal passes through a high-pass filter circuit (i.e., air conduction filter circuit 102) to retain high-frequency signals, while the bone conduction microphone signal passes through a low-pass filter circuit (bone conduction filter circuit 104) to retain low-frequency signals. The filtering effect varies depending on the position of the noise reduction switch 201. The filtered signals (the high-pass filter circuit and the low-pass filter circuit) then pass through a signal mixing circuit 105 for gain adjustment, amplification, and mixing, before being output through the headphone jack 106 to the intercom.

[0082] The values of the resistors and capacitors in the air conduction filter circuit 102 , the bone conduction filter circuit 104 and the signal mixing circuit 105 may be fixed or variable.

[0083] Through this optional example, a mixture of air conduction microphones and bone conduction microphones can be achieved. The provided solution can be used on wired headsets for intercoms at a low cost. It not only ensures the sound pickup performance, but also solves the problem that wired headsets for intercoms do not have a solution for mixing bone conduction microphones and air conduction microphones. It also solves the problem that some users have poor sound pickup effects when using bone conduction microphones, thereby improving the experience of using bone conduction pickup headsets on intercoms.

[0084] In the above embodiments of the present application, the descriptions of each embodiment have their own emphasis. For parts not described in detail in one embodiment, please refer to the relevant descriptions of other embodiments. Circuits in different embodiments or examples can be combined without contradiction. Circuits described as separate components may or may not be physically separate. The location of each circuit can be flexibly set according to the design requirements of the wired headset, as long as the connection relationship between each circuit or component meets the requirements.

[0085] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A bone conduction pickup earphone, characterized in that: include: An air conduction microphone, wherein the air conduction microphone is a microphone that picks up voice signals through an air path; an air conduction filter circuit, configured to filter the air conduction voice signal picked up by the air conduction microphone and output the filtered air conduction voice signal; A bone conduction microphone, wherein the bone conduction microphone is a microphone used to pick up voice signals from vibrations of a specified part of the body; a bone conduction filter circuit, configured to filter the bone conduction voice signal picked up by the bone conduction microphone and output the filtered bone conduction voice signal; a signal mixing circuit, configured to perform signal mixing processing on the filtered air conduction voice signal and the filtered bone conduction voice signal, and output a mixed voice signal; The headphone interface is used to output the mixed voice signal to the connected device to which the bone conduction pickup headphone is connected.

2. The bone conduction pickup earphone according to claim 1, characterized in that: The bone conduction pickup earphone further includes: a noise reduction switch for selecting a gear used by the bone conduction pickup earphone from a plurality of gears; The air conduction filter circuit includes a plurality of high-pass filter circuits, and the bone conduction filter circuit includes a plurality of low-pass filter circuits. The high-pass filter circuits in the plurality of high-pass filter circuits and the low-pass filter circuits in the plurality of low-pass filter circuits form a plurality of filter circuit pairs, and each filter circuit in the plurality of filter circuit pairs corresponds to one of the plurality of gears.

3. The bone conduction pickup earphone according to claim 2, characterized in that: The multiple high-pass filter circuits are multiple RC high-pass filter circuits connected in parallel, and each of the multiple RC high-pass filter circuits includes a resistor and a capacitor connected in series; The multiple low-pass filter circuits are multiple RC low-pass filter circuits, each of the multiple RC low-pass filter circuits includes a resistor and a capacitor, the resistors of different RC low-pass filter circuits in the multiple RC low-pass filter circuits are connected in parallel, the capacitors in the multiple RC low-pass filter circuits are the same capacitor, and in the multiple RC low-pass filter circuits, the rear ends of the multiple parallel resistors are grounded via the capacitors and connected to the input end of the signal mixing circuit.

4. The bone conduction pickup earphone according to claim 2, characterized in that: The multiple gears include a pure air conduction gear. When the noise reduction switch selects the pure air conduction gear, the air conduction voice signal is directly output to the headphone interface, the connection between the bone conduction microphone and the bone conduction filter circuit is disconnected, and the connection between the air conduction microphone and the air conduction filter circuit is disconnected.

5. The bone conduction pickup earphone according to claim 4, characterized in that: The bone conduction pickup earphone also includes: The control component is used to detect environmental noise and switch the gear position of the noise reduction switch based on the intensity of the detected environmental noise.

6. The bone conduction pickup earphone according to claim 5, characterized in that: The control component is connected to the air conduction microphone, and the environmental noise is detected from the air conduction voice signal.

7. The bone conduction pickup earphone according to claim 5, characterized in that: The multiple gears also include a first noise reduction gear and a second noise reduction gear. The first noise reduction gear corresponds to the first filter circuit pair among the multiple filter circuit pairs, and the second noise reduction gear corresponds to the second filter circuit pair among the multiple filter circuit pairs. The filtering frequency division point of the first filter circuit pair is smaller than the filtering frequency division point of the second filter circuit pair. The intensity of the ambient noise corresponding to the pure air conduction gear is smaller than the intensity of the ambient noise corresponding to the first noise reduction gear, and the intensity of the ambient noise corresponding to the first noise reduction gear is smaller than the intensity of the ambient noise corresponding to the second noise reduction gear.

8. The bone conduction pickup earphone according to claim 1, characterized in that: The signal mixing circuit includes: a first adjustable resistor, a second adjustable resistor, a third adjustable resistor, and an operational amplifier, wherein the first adjustable resistor and the second adjustable resistor are used to adjust the input ratio of the filtered air conduction voice signal and the filtered bone conduction voice signal, wherein the front end of the first adjustable resistor is connected to the output end of the air conduction filter circuit, the rear end of the first adjustable resistor is connected to the first input end of the operational amplifier, the front end of the second adjustable resistor is connected to the output end of the bone conduction filter circuit, and the rear end of the second adjustable resistor is connected to the first input end of the operational amplifier; The third adjustable resistor is used to adjust the amplification gain after signal mixing, wherein the third adjustable resistor is connected between the first input terminal of the operational amplifier and the output terminal of the operational amplifier; The operational amplifier is used to perform signal amplification processing on the voice signal input from the first input terminal of the operational amplifier, wherein the second input terminal of the operational amplifier is grounded.

9. The bone conduction pickup earphone according to claim 8, characterized in that: The bone conduction pickup earphone also includes: a first adjusting component, configured to adjust the resistance of at least one of the first adjustable resistor and the second adjustable resistor; a second adjusting component, configured to adjust the resistance of the third adjustable resistor; Wherein, the first adjusting component and the second adjusting component are the same component or different components.

10. The bone conduction pickup earphone according to any one of claims 1 to 9, characterized in that: The bone conduction pickup earphone also includes: PTT button and speaker.

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