Patent Description:
The voice recognition system and voice communication system usually use an acoustic microphone to sense sound waves generated by the user when the user is speaking to obtain the user's voice. With the maturity and wide-scale application of Internet technology and the popularization of Internet of Things (IoT) products, the requirements for voice processing are getting higher.

In the process of voice recognition and voice communication, the noise caused by the user's surroundings or the user is an important problem to be addressed in voice processing.

For some currently known headphone products, especially earbuds, their usage status is determined by sensing the wearer's bone conduction vibration, thereby improving the voice processing effect, such as improving voice intelligibility and reducing voice recognition error rate.

Those skilled in the art are also devoted to the exploration of the acquisition method of bone conduction vibration and the use of the acquired signal.

<CIT> discloses a headphone/earphone with an accelerometer for bone conduction sound detection. It does not disclose a gyroscope, and thus no quadrature error signal thereof.

<CIT> discloses a device with a sensor for bone conduction sound to be attached close to the ear of a user. The sensor is configured to, during operation of the bone conduction device, sense a non-audible input from a region of the user's skin. The sensor may include a gyroscope, among other sensors. It does not disclose that the gyroscope is used for detection of for bone conduction sound, nor a quadrature error signal.

<CIT> discloses a hand-worn device with a sensor of the movement and gesture of the finger. The sensor can be an accelerometer or a gyroscope. The voice module, the microphone, the bone conduction actuator and the sensor may be provided on the ring member. The bone conduction actuator can communicate with the communication module or with other communication devices or with a cellular network. It does not disclose that the gyroscope is used for detection of for bone conduction sound, nor a quadrature error signal.

In view of this, an objective of the present disclosure is to provide a headphone, including a gyroscope and a transmission assembly, wherein the gyroscope is configured to sense a bone conduction vibration and provide a quadrature error signal for reflecting the bone conduction vibration. The present invention provides a headphone according to claim <NUM>, and an electronic device, comprising the such a headphone, according to claim <NUM>.

The transmission assembly is configured to act directly or indirectly on the gyroscope or an inertial measurement unit (IMU) including the gyroscope. The transmission assembly is configured to transmit the bone conduction vibration to the gyroscope to make the gyroscope strain, thereby causing the quadrature error signal of the gyroscope to change.

The transmission assembly has at least one end fixed to the shell of the headphone and at least one end connected to, abutting against, or spaced a certain distance from the gyroscope or the IMU including the gyroscope.

The transmission assembly includes transmission bars. The connection of the transmission bars to the shell defining sensing positions; wherein when the headphone is worn, the sensing positions are located within the wearer's ear canal in contact with the wall of the ear canal, and the sensing positions are adapted to receive bone conduction vibrations generated by the wearer's speech.

Further, preferably, the transmission assembly has a symmetrical structure.

Further, preferably, the transmission assembly may include a first transmission component and a second transmission component, which may be respectively arranged on two sides of the gyroscope. The first transmission component has one end fixed to the shell of the headphone and the other end connected to, abutting against, or spaced a certain distance from the gyroscope or the IMU including the gyroscope. The second transmission component has one end fixed to the shell of the headphone and the other end connected to, abutting against, or spaced a certain distance from the gyroscope or the IMU including the gyroscope.

Further, preferably, the transmission assembly may include a first end, a second end, and a third end. The first end and the second end may be separately fixed to the shell of the headphone, and the third end may be connected to, abuts against, or may be spaced a certain distance from the gyroscope or the IMU including the gyroscope.

Further, preferably, the transmission assembly may be made of a rigid material or may be made of an elastic material suitable for transmitting the bone conduction vibration to the gyroscope or the IMU including the gyroscope and making the gyroscope strain.

Further, preferably, the gyroscope or the IMU including the gyroscope may be fixed to a base plate. The transmission assembly may directly act on the base plate, thereby indirectly acting on the gyroscope or the IMU including the gyroscope through the base plate.

The present disclosure further provides an electronic device including the above headphone.

Further, preferably, the quadrature error signal of the gyroscope may be used for user interface (UI) gesture detection, voice activity detection, voice recognition, active noise control, noise suppression, and voice intelligibility enhancement.

The headphone of the present disclosure has the following technical effects.

To make the objectives, features, and effects of the present disclosure fully understood, the concepts, specific structures, and technical effects of the present disclosure are clearly and completely described below in conjunction with the examples and drawings.

It should be understood that, in the description of the present disclosure, the orientation or position relationships indicated by terms, such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", and "counterclockwise", are based on what are illustrated in the drawings. These terms are merely intended to facilitate and simplify the description of the present disclosure, rather than to indicate or imply that the mentioned device or components must have a specific orientation or must be constructed and operated in a specific orientation. Therefore, these terms should not be understood as a limitation to the present disclosure. The drawings are schematic diagrams or conceptual diagrams, in which the relationship between the thickness and width of each part and the proportional relationship between each part are not completely consistent with the actual value.

<FIG> and <FIG> are schematic diagrams according to an embodiment of the present disclosure. A headphone <NUM> includes a shell <NUM>, a printed circuit board (PCB) <NUM>, a transmission assembly <NUM>, and a gyroscope <NUM>.

The PCB <NUM> is fixedly provided in the shell <NUM>, and the gyroscope <NUM> is fixed on the PCB <NUM>. The transmission assembly <NUM> includes transmission bars <NUM> and <NUM>. The transmission bars <NUM> and <NUM> are made of the same material and have the same structure.

In this embodiment, the gyroscope <NUM> is provided in the shell <NUM> and close to an upper part of the headphone <NUM>. The transmission bars <NUM> and <NUM> are symmetrically arranged on two sides of the gyroscope <NUM>. The transmission bar <NUM> has one end fixed to one inner side of the shell <NUM> and the other end connected to the gyroscope <NUM>. The transmission bar <NUM> has one end symmetrical with the one end of the transmission bar <NUM> and fixed to the other inner side of the shell <NUM> and the other end connected to the gyroscope <NUM>.

In this embodiment, the transmission bars <NUM> and <NUM> are fixedly connected to the gyroscope <NUM> by welding. They may also be fixedly connected by other means, such as gluing, etc., which are not limited herein.

The connection of the transmission bars <NUM> and <NUM> to the shell <NUM> defines sensing positions <NUM> and <NUM>. The sensing positions <NUM> and <NUM> must satisfy the following condition. When the headphone <NUM> is worn, the sensing positions <NUM> and <NUM> are located within the wearer's ear canal in contact with the wall of the ear canal, and the contact positions are adapted to receive bone conduction vibrations generated by the wearer's speech. The bone conduction vibrations are generated by the movement of the bones and soft tissues of the head and face of the wearer when the wearer speaks. The bone conduction vibrations are transmitted to the wall of the ear canal. The sensing positions <NUM> and <NUM> should be suitable for sensing bone conduction vibrations.

When the wearer is speaking, bone conduction vibrations on the wall of the ear canal act on the sensing positions <NUM> and <NUM>. In other words, the stress states at the sensing positions <NUM> and <NUM> are constantly changing with the vibrations. The bone conduction vibrations sensed by the sensing positions <NUM> and <NUM> are transmitted to the gyroscope <NUM> through the transmission bars <NUM> and <NUM>, respectively, such that the stress state of the gyroscope <NUM> changes continuously with the vibrations. If the gyroscope <NUM> is strained under a stress, the strain state also changes continuously with the vibration. This strain can be sensitively detected by the gyroscope <NUM>.

<FIG> is a schematic diagram of quadrature coupling of a capacitive micro-electromechanical-system (MEMS) gyroscope. The capacitive MEMS gyroscope is a micro-machined device. It mainly relies on a Coriolis force to detect an angular velocity signal and has two working modes, namely a drive mode and a detection mode. Ideally, when a drive end of the gyroscope applies an eigenfrequency electrical signal in the drive mode, a proof mass of the gyroscope will vibrate back and forth at an eigenfrequency on a drive axis (X-axis in <FIG>). When there is a Z-axis angular velocity input from outside, under the action of the Coriolis force, the proof mass will vibrate on a detection axis (Y-axis in <FIG>) at the same time. There is a linear relationship between the vibration amplitude and the angular velocity, and the current angular velocity can be calculated by detecting the vibration amplitude of the proof mass on the detection axis.

Manufacturing process defects in micromachining can lead to a non-ideal structure in the gyroscope. Thus, in actual operation, the proof mass does not vibrate strictly on the drive axis in the drive mode. The actual vibration direction may have a small angular deviation from the drive axis. This deviation will cause the vibration of the drive axis to couple directly to the detection axis, such that the gyroscope will still have a detection signal output even when the angular velocity input is zero. This phenomenon is called a quadrature error.

The quadrature error signal of the gyroscope is easily affected by stress and deformation. However, since the quadrature error signal and the detection signal have a <NUM>° phase difference, it can be prevented from being demodulated during the demodulation process to avoid its change from affecting the normal output result of the gyroscope. Therefore, the influence of the external force on the gyroscope can be reflected and quantified by demodulating the quadrature error signal.

<FIG> shows a flowchart of processing an output signal of the gyroscope according to the embodiment. A signal output by a detection capacitor is converted by C/V, and an angular velocity detection signal for characterizing the angular velocity and a quadrature error signal are demodulated, respectively.

As previously mentioned, the quadrature error is caused by the non-ideal structure produced by the manufacturing process defect of the micromachining, which is determined by the micromechanical structure. When the gyroscope is in a normal state, the quadrature error signal will not change regardless of whether there is an angular velocity input.

However, when the gyroscope is subj ected to an external force to cause stress and deformation, the quadrature error signal will change greatly. Although the stress and deformation will act on the angular velocity detection signal and the quadrature error signal of the gyroscope at the same time, the influence on the quadrature error signal is much greater than that on the angular velocity detection signal. In an actual experiment, the change of the quadrature error signal and the change of the angular velocity detection signal under the strain state were compared for gyroscopes with different structural designs. The experiment found that the change caused by the quadrature error signal was about <NUM>-<NUM> times larger than that caused by the angular velocity detection signal. For the same structural design, the ratio of the change of the quadrature error signal to the change of the angular velocity detection signal is basically fixed. It can be seen that, compared with the angular velocity detection signal, the quadrature error signal has a higher sensitivity to the external force. Thus, as long as the external force is controlled within an appropriate range, the gyroscope can be used to detect external forces without affecting its normal function (angular velocity detection).

In this embodiment, when the wearer does not speak, the stress states at the sensing positions <NUM> and <NUM> basically do not change. The quadrature error signal of the gyroscope <NUM> is basically unchanged, and the quadrature error signal of the gyroscope <NUM> is not affected regardless of whether there is an angular velocity input. When the wearer speaks, bone conduction vibrations are created in the wall of the ear canal and the bone conduction vibrations are sensed at the sensing positions <NUM> and <NUM>. The bone conduction vibrations are conducted to the gyroscope <NUM> through the transmission bars <NUM> and <NUM>. Under the action of the bone conduction vibrations, the stress state of the gyroscope <NUM> is constantly changing, and the strain state caused by the external force is also constantly changing. When the strain state changes, the quadrature error signal of the gyroscope <NUM> correspondingly fluctuates. As mentioned earlier, the quadrature error signal is affected by the strain change approximately <NUM> to <NUM> times more than the angular velocity detection signal. The strain of the gyroscope <NUM> caused by the bone conduction vibrations can be sensitively reflected by the quadrature error signal of the gyroscope. The influence on the angular velocity detection signal is easy to control within an acceptable range that is relatively small.

To transmit the bone conduction vibrations to the gyroscope <NUM>, the transmission bars <NUM> and <NUM> are preferably made of a rigid material and may also be made of an elastic material suitable for transmitting the bone conduction vibrations to the gyroscope <NUM> and making the gyroscope <NUM> strain.

In this embodiment, the transmission bars <NUM> and <NUM> act on one end of the gyroscope <NUM> and are fixedly connected to the gyroscope <NUM>. However, based on the principle that the gyroscope <NUM> senses the bone conduction vibrations, a non-fixed connection may be used. For example, the transmission bars <NUM> and <NUM> may act on one end of the gyroscope <NUM> and abut against the gyroscope <NUM> to realize vibration conduction. In actual assembly, the transmission bars <NUM> and <NUM> may not completely fit against the gyroscope <NUM>. However, if vibration conduction can be achieved (acting on or intermittently acting on the gyroscope <NUM> during the conduction vibration), even a small gap is acceptable.

<FIG> shows an alternative transmission bar configuration. One end of each of transmission bars <NUM> and <NUM> acting on the gyroscope <NUM> is configured as a concave structure matching the shape of the gyroscope <NUM>. The concave structure does not need to be fixedly connected to the gyroscope <NUM> and can also achieve stable position limiting.

<FIG> are structural diagrams according to another embodiment of the present disclosure. A headphone <NUM> includes a shell <NUM>, a PCB <NUM>, a transmission assembly <NUM>, and a gyroscope <NUM>.

Different from the structure shown in <FIG>, in this embodiment, the transmission bars <NUM> and <NUM> are symmetrically arranged on two sides of the PCB <NUM>. As shown in <FIG>, extension lines of the transmission bars <NUM> and <NUM> pass through the gyroscope <NUM>. The transmission bar <NUM> has one end fixed to an inner side of the shell <NUM> and the other end connected to the PCB <NUM>. The transmission bar <NUM> has one end symmetrical with the transmission bar <NUM> and fixed to the other inner side of the shell <NUM> and the other end connected to the PCB <NUM>. The methods of connecting the transmission bars <NUM> and <NUM> to the PCB <NUM> include but are not limited to, fixed connection by welding, gluing, etc., and plug connection realized by matching grooves provided on the PCB <NUM> and the transmission bars <NUM> and <NUM>. Of course, the transmission bars <NUM> and <NUM> may also abut against the PCB <NUM> or have an acceptable gap, which is not limited herein.

In this embodiment, the transmission bars <NUM> and <NUM> transmit the bone conduction vibrations to the PCB <NUM>. The PCB <NUM> generates a strain, thereby driving the gyroscope <NUM> to strain. In this way, bone conduction vibration sensing is achieved through the gyroscope <NUM>. Specifically, the bone conduction vibrations are reflected by the quadrature error signal of the gyroscope <NUM>.

For the connection or cooperation (non-fixed connection) method of the transmission assembly <NUM> and the gyroscope <NUM>, the selection of the material of the transmission assembly <NUM>, the selection of the connection positions of the transmission assembly <NUM> and the shell <NUM>, and the sensing positions defined by the connection positions, reference can be made to the above embodiments, which will not be repeated herein.

<FIG> is a structural diagram according to another preferred embodiment of the present disclosure. A headphone <NUM> includes a shell <NUM>, a PCB <NUM>, a transmission assembly <NUM>, and a gyroscope <NUM>.

In this embodiment, the gyroscope <NUM> is provided in the shell <NUM> and at a central part of the headphone <NUM>. The transmission bars <NUM> and <NUM> are symmetrically arranged on two sides of the gyroscope <NUM>. The transmission bar <NUM> has one end fixed to one inner side of the shell <NUM> and the other end connected to the gyroscope <NUM>. The transmission bar <NUM> has one end symmetrical with the one end of the transmission bar <NUM> and fixed to the other inner side of the shell <NUM> and the other end connected to the gyroscope <NUM>.

Different from the structure shown in <FIG>, in this embodiment, since the position of the gyroscope <NUM> is moved downward, the transmission bars <NUM> and <NUM> are not in the same extending direction but are at an angle with respect to the gyroscope <NUM>. Likewise, the bone conduction vibrations are transmitted to the gyroscope <NUM> through the transmission bars <NUM> and <NUM> to make the gyroscope strain, such that bone conduction vibration sensing is realized through the gyroscope <NUM>. Specifically, the bone conduction vibrations are reflected by the quadrature error signal of the gyroscope <NUM>.

<FIG> is a structural diagram according to another embodiment of the present disclosure. A headphone <NUM> includes a shell <NUM>, a PCB <NUM>, a transmission assembly <NUM>, and a gyroscope <NUM>.

The PCB <NUM> is fixedly provided in the shell <NUM>, and the gyroscope <NUM> is fixed on the PCB <NUM>. The transmission assembly <NUM> includes a transmission section <NUM>, a transmission section <NUM>, and a transmission section <NUM>. The transmission section <NUM>, the transmission section <NUM>, and the transmission section <NUM> are integrally formed.

In this embodiment, the gyroscope <NUM> is provided in the shell <NUM> and at a lower part of the headphone <NUM>. The transmission section <NUM> and the transmission section <NUM> are arranged symmetrically. The transmission section <NUM> extends along an axis of symmetry of the transmission section <NUM> and the transmission section <NUM>. One end of each of the three sections is connected at one place to form a Y-shaped structure. The other end of the transmission section <NUM> is fixed on one inner side of the shell <NUM>, the other end of the transmission section <NUM> is symmetrical with the transmission section <NUM> and fixed on the other inner side of the shell <NUM>, and the other end of the transmission section <NUM> is connected to the gyroscope <NUM>.

For the connection or cooperation (non-fixed connection) method of the transmission section <NUM> and the gyroscope <NUM>, the selection of the material of the transmission assembly <NUM>, the selection of the connection positions of the transmission assembly <NUM> and the shell <NUM>, and the sensing positions defined by the connection positions, reference can be made to the above embodiments, which will not be repeated herein.

When the wearer is speaking, bone conduction vibrations on the wall of the ear canal act on the sensing positions (the sensing positions in this embodiment are the same as the sensing positions <NUM> and <NUM> shown in <FIG>). The transmission sections <NUM> and <NUM> transmit the bone conduction vibrations to the transmission section <NUM>. The transmission section <NUM> then transmits the bone conduction vibrations to the gyroscope <NUM>. In this way, bone conduction vibration sensing is achieved through the gyroscope <NUM>. Specifically, the bone conduction vibrations are reflected by the quadrature error signal of the gyroscope <NUM>.

In all the above embodiments, the gyroscope is provided in the headphone. In other embodiments, the headphone is provided with an IMU, and the gyroscope is included in the IMU. Correspondingly, the same technical effect can also be achieved by replacing the gyroscope in all the above embodiments with the IMU.

In all the above embodiments, the transmission assembly has a symmetrical structure. This is because the gyroscope or IMU is located at a central axis, and the transmission assembly with the symmetrical structure facilitates the manufacture of each component (reduces the types of component manufacture). Regardless of whether the gyroscope or IMU is provided at the central axis or is provided away from the central axis, the asymmetrical structure of the transmission assembly will not affect the gyroscope's bone conduction vibration sensing, as long as the transmission assembly can play the role of conducting vibration.

The processing and utilization of the quadrature error signal of the gyroscope can be implemented in a circuit manner and/or by a processor. For example, if the headphone is connected to an electronic device, such as an audio playback device, a mobile phone, an augmented reality (AR) device, or a virtual reality (VR) device, or is used as an integral part of the electronic device, the processing and utilization of the quadrature error signal can be completed by the processor in the electronic device. The specific implementation is not limited herein.

In the above solution, the gyroscope can be used to sense the external force, such as the bone conduction vibration, and reflect the received external force through the quadrature error signal. Based on this, in the above solution, the quadrature error signal provided by the gyroscope can be used for data and audio processing or as a necessary means to realize functions, including but not limited to user interface (UI) gesture detection, voice activity detection, voice recognition, active noise control, noise suppression, and voice intelligibility enhancement, etc..

For example, when the headphone in the above embodiments detects the bone conduction vibrations from the wearer, it can be determined that the headphone wearer is speaking, which will facilitate some functional improvements. When the headphone wearer uses a voice, such as "Hi, Siri" to wake up the mobile phone, the gyroscope senses the bone conduction vibrations, and the quadrature error signal generated by the gyroscope changes accordingly. These signals are picked up by the mobile phone connected to the headphone. The mobile phone determines that the wearer of the headphone is speaking according to the signal and deems that the voice that wakes up the mobile phone is sent by the wearer of the headphone. If no bone conduction vibrations are detected, the quadrature error signal has little or no change, it is considered that the voice that wakes up the mobile phone is not provided by the wearer of the headphone, so the mobile phone cannot be woken up.

For another example, when a call is answered, when bone conduction vibrations from the headphone wearer are detected, it is determined that the headphone wearer is speaking, and the audio signal detected by a microphone is conducted to a receiving party. When no bone conduction vibrations are detected, it is determined that the headphone wearer is not speaking. In this case, the audio signal detected by the microphone is regarded as ambient noise, and there is no need to transmit the microphone signal to the receiving party, thereby improving voice recognition and call quality.

The above description is intended to illustrate that the quadrature error signal of the gyroscope in the above solution can be used for many functions to improve existing functions or generate new functions but is not intended to limit the scope of application.

Claim 1:
A headphone, comprising a gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) and a transmission assembly (<NUM>, <NUM>, <NUM>, <NUM>), wherein the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) is configured to sense a bone conduction vibration and provide a quadrature error signal for reflecting the bone conduction vibration; the transmission assembly (<NUM>, <NUM>, <NUM>, <NUM>) is configured to act directly or indirectly on the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) or an inertial measurement unit (IMU) comprising the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>), the transmission assembly (<NUM>, <NUM>, <NUM>, <NUM>) has at least one end fixed to a shell (<NUM>, <NUM>, <NUM>, <NUM>) of the headphone (<NUM>, <NUM>, <NUM>, <NUM>) and at least one end connected to, abutting against, or spaced a certain distance from the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) or the IMU comprising the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>), the transmission assembly (<NUM>, <NUM>, <NUM>, <NUM>) is further configured to transmit the bone conduction vibration to the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) to make the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) strain, thereby causing the quadrature error signal of the gyroscope (<NUM>, <NUM>, <NUM>, <NUM>) to change; and wherein the transmission assembly includes transmission bars, the connection of the transmission bars to the shell (<NUM>, <NUM>, <NUM>, <NUM>) defining sensing positions; wherein when the headphone (<NUM>, <NUM>, <NUM>, <NUM>) is worn, the sensing positions are located within the wearer's ear canal in contact with the wall of the ear canal, and the sensing positions are adapted to receive bone conduction vibrations generated by the wearer's speech.