WO2016167508A1 - Noise cancellation method and device for mobile sound device - Google Patents

Abstract

Disclosed is a noise cancellation method and device for a mobile sound device, which can cancel external noise, heard by a user through an ordinary earphone, using the earphone in a mobile device having a microphone. A method for cancelling noise, output to an earphone, by a noise cancellation device mounted or coupled to a mobile device comprises the steps of: receiving an input of ambient noise through a microphone of the mobile device; estimating repetitive noise heard by a user on the basis of the noise; generating an antiphase signal having inverted phase to the repetitive noise; and outputting the antiphase signal to the earphone connected to the mobile device.

Description

Noise canceling method and device for mobile audio equipment

Embodiments of the present invention relate to a noise reduction technology of a mobile acoustic device, and more particularly, to a noise reduction method and apparatus for a mobile acoustic device capable of removing noise from ordinary earphones connected to a mobile device. will be.

With the development of mobile devices and network technologies, the population and listening time of listening to music and broadcasting through mobile devices are increasing considerably. However, there is a lot of noise in the place where the sound is mainly listened. In the room, air conditioners and heaters generate noise, and in vehicles, such as airplanes, buses, and trains, noise is generated repeatedly by peripheral devices and people. In the presence of noise, if the user repeatedly listens to the sound using earphones connected to the mobile device, the user may hear a loud sound more than necessary, such as hearing loss and hearing loss.

To solve this problem, some earphones are currently on the market for noise reduction. These have a microphone attached directly behind the earphones and a separate circuit attached to the earphone wire. That is, the earphone with the conventional noise canceling function has a disadvantage in terms of design due to the addition of additional hardware or technology, the high price point is formed, as well as a separate noise canceling circuit coupled to the large earphone part and earphone cable. And, above all, since the role of removing noise is centered on the microphone attached to the earphone, it is inconvenient to always carry the corresponding earphone in order to listen to the sound from which the noise is removed.

An object of the present invention for solving the problems of the prior art as described above, the user using the normal earphones in the mobile device to remove the noise of the mobile acoustic device to be able to listen to the sound from which the noise repeatedly generated from the outside repeatedly To provide a method and apparatus.

In order to achieve the above object, in one aspect of the present invention, a method for removing noise heard by the user through the earphone in the noise reduction device mounted on or coupled to the mobile device, the step of receiving ambient noise through the microphone of the mobile device Estimating the repetitive noise the user hears based on the noise, generating an antiphase signal of the repetitive noise, and outputting the antiphase signal through an earphone connected to the mobile device. Provides noise reduction method.

Here, the estimating of the noise may use a sound related parameter according to a mobile device, a user-specified modeling parameter for the mobile device, a sound related parameter according to an earphone type, or a combination thereof. The user-defined modeling parameter may include relative position information between the right earphone, the left earphone, and the mobile device belonging to the earphone.

Here, the estimating of the noise may include determining a repetitive noise by analyzing a location and a shape of a noise source obtained from the mobile device, and a type of noise that the user hears through earphones connected to the mobile device with respect to the repetitive noise. It may include the step of modeling.

Here, the step of determining whether the noise is a repetitive noise, after cutting the noise of a certain time interval in a certain period, the portion of the waveform whose noise waveform in each period is similar or the magnitude difference of the noise is equal to or less than a certain threshold in a certain period in the entire period It can be determined whether it occupies more than one.

In the modeling step, the user input may be acquired through the user interface of the mobile device, and the noise may be predicted in the position of the earphone based on the obtained user input. The user input may include selection information about the type of earphone and relative position information between the right earphone, the left earphone, and the mobile device belonging to the earphone.

Here, after the step of generating the anti-phase signal, the noise canceling method, according to the user input obtained through the user interface of the mobile device to perform phase adjustment, gain adjustment, frequency fine adjustment or a combination thereof The method may further include a user feedback step.

Here, the user feedback step may further obtain a user input through a user interface for adjusting the position of the noise source, adjusting the relative position between the mobile device and the earphone, adjusting the earphone type, adjusting the gain for each frequency, or a combination thereof.

Here, in the step of estimating the noise, the noise obtained through a single microphone of the mobile device may be classified by frequency, and the noise by frequency may be determined using a filter to determine whether the noise is repetitive. In this case, generating the antiphase signal may generate a pseudo antiphase signal having an arbitrary phase and gain using repetitive noise.

Here, generating the anti-phase signal may include obtaining a user input for the pseudo anti-phase signal through a user interface, and responsive to the user input, phase adjustment, gain adjustment, frequency fine adjustment, or a combination thereof. Can be performed.

Here, generating the antiphase signal includes an amplitude interval of less than or equal to a certain magnitude for a predetermined time or more for the estimated repetitive noise or a composite signal of the antiphase signal and the estimated repetitive noise. The antiphase signal may be generated, or an antiphase signal may be generated by shifting or inverting the phase of the noise by a half cycle or 180 ° so as to have a value close to the amplitude 0 for a predetermined period.

Here, in the outputting of the antiphase signal, the antiphase signal may be output to the earphone together with the sound signal that the user wants to hear through the mobile device, or the antiphase signal may be combined with the sound signal and output.

In another aspect of the present invention to achieve the above object, a noise control device that is mounted on or coupled to a mobile device to remove noise that the user hears through earphones connected to the mobile device, the memory for storing the program, and connected to the memory And a processor configured to execute a program, wherein the processor receives, by the program, ambient noise through a microphone of the mobile device, estimates the repetitive noise heard by the user based on the noise, and generates an antiphase signal for the repetitive noise. Provided is a noise canceling device for a mobile audio device, which generates and outputs an antiphase signal to an earphone.

In another aspect of the present invention to achieve the above object, a noise canceling device for removing the noise that the user hears through the earphone connected to the mobile device mounted on or coupled to the mobile device, the ambient noise through the microphone of the mobile device The mobile audio device includes an input unit for receiving an input unit, an estimator for estimating the repetitive noise that the user hears based on the noise, a generator for generating an antiphase signal of the repetitive noise, and an output unit for outputting the antiphase signal to the earphones. To provide a noise reduction device.

Here, the estimator may estimate the noise using a sound related parameter according to the mobile device, a user-specified modeling parameter for the mobile device, a sound related parameter according to the earphone type, or a combination thereof. The custom modeling parameter may include relative position information between the right earphone, the left earphone, and the mobile device belonging to the earphone.

Here, the estimating unit, a repeating noise determination unit for determining whether the repetitive noise by analyzing the position and shape of the noise source of the noise in the mobile device, and a modeling unit for modeling the shape of the noise that the user of the earphone based on the repetitive noise It may include.

Here, the repetitive noise determination unit divides the noise of a predetermined time interval into a predetermined period, and determines whether a portion having a similar waveform or a magnitude difference of the noise in each period occupies a predetermined ratio or more in the entire period. Can be.

Here, the modeling unit may determine the noise type that the user hears through the earphone based on the user input obtained through the user interface of the mobile device. The user input may include relative position information between the right earphone and the left earphone and the mobile device belonging to the earphone, the type information of the earphone, and a combination thereof.

Here, the estimating unit may include a repetitive noise determination unit for dividing the noise acquired through the microphone for each frequency and determining whether the noise for each frequency is repetitive noise using a filter. The generator may include a pseudo signal generator or an antiphase signal generator that generates a pseudo antiphase signal having an arbitrary phase and gain using repetitive noise.

Here, the noise canceling device performs phase adjustment, gain adjustment, frequency fine adjustment, or a combination of the pseudo antiphase signals in response to user input obtained through the user interface of the mobile device, thereby converting the pseudo antiphase signals. The apparatus may further include an adjusting unit or a user adjusting module configured to correct or correct at least one or more times as an antiphase signal to be output to the earphone.

Here, the noise reduction device may further include a synthesis unit for outputting the antiphase signal to the earphone together with the sound signal that the user wants to hear through the mobile device, or by synthesizing the antiphase signal to the sound signal.

In case of using the method and apparatus for removing noise of a mobile acoustic device according to the present invention as described above, after modeling the noise to be heard by a user using a normal earphone in a mobile device having a microphone, the anti-phase modeled noise is anti-phase. ) By outputting the signal along with the original signal to be listened to, the user can hear the sound substantially removed when the user listens to the sound through the normal earphone.

That is, according to the present invention, by estimating the external noise that the user hears using a microphone provided in or coupled to a mobile device and general earphones, and outputting the anti-phase signal of the estimated noise to the earphone, It is possible to have the environment eliminated, and furthermore to have the effect of actually only hearing the sound originally intended to be heard.

In particular, when using the method and apparatus for noise reduction according to the present invention, since a microphone mounted on a mobile device capable of reproducing sound and the computing power of the mobile device itself are used, general earphones (low-cost earphones, etc.) without special earphones for noise reduction are used. It can also be applied to use, and thus has the advantage that it can be widely used for general users. In addition, there is an advantage that can be applied to most mobile devices with a built-in microphone.

In addition, the noise canceling method and apparatus of the mobile acoustic apparatus according to the present invention are more effective in a specific environment in which repeated noise occurs. For example, a user's mobile acoustic device located in such a repetitive noise environment in that a large number of users' acoustic listening is performed in fixed indoor environments such as vehicles (subway, buses, aircraft, ships), offices, and homes. The advantage of the noise reduction is very high.

In addition, in the case of using the noise canceling method and apparatus of the mobile acoustic device according to the present invention, providing a quiet environment in which the ambient noise is removed by simply plugging the general earphone plugged into the mobile audio device into the ear to a user who does not intend to listen to the sound. There is an advantage to this. That is, there is an advantage in that it is possible to provide a mobile device having a noise reduction function.

1 is an exemplary view for explaining a mobile acoustic listening environment using a noise canceling apparatus (hereinafter, simply referred to as a noise canceling apparatus) of a mobile acoustic apparatus according to an embodiment of the present invention in comparison with a comparative example.

FIG. 2 is a flowchart illustrating a noise canceling method (hereinafter, simply referred to as a noise canceling method) of the mobile acoustic device of the present embodiment applicable to the mobile device of FIG. 1.

FIG. 3 is a schematic block diagram of a mobile device equipped with the noise canceling apparatus of FIG. 1.

4 is an exemplary view of a mobile device incorporating a noise canceling device according to another embodiment of the present invention.

FIG. 5 is a schematic configuration diagram which may be employed in the noise reduction apparatus of FIG. 4.

6 is an exemplary view of a mobile device incorporating a noise canceling device according to another embodiment of the present invention.

Figure 7 is a schematic block diagram of a functional block that can be employed in the noise reduction device according to an embodiment of the present invention.

FIG. 8 is a block diagram of another embodiment of an estimator that may be employed in the apparatus for removing noise of FIG. 7.

FIG. 9 is a partial block diagram of a modification of the noise canceling apparatus of FIG. 7.

10 is a flowchart of a noise removing method according to another embodiment of the present invention.

FIG. 11 is a flowchart of user feedback that may be employed in the method for removing noise of FIG. 10.

FIG. 12 is an exemplary diagram illustrating a signal in a process of estimating an antiphase signal of noise by the user feedback of FIG. 11.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first, second, A, and B may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed in accordance with their meaning in the context of the related art, and shall not be construed in an ideal or excessively formal sense unless clearly defined herein.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention. As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. In the following description of the present invention, the same reference numerals are used for the same elements in the drawings and redundant descriptions of the same elements will be omitted. In addition, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is an exemplary view for explaining a mobile sound listening environment using a noise canceling device of a mobile sound device according to an embodiment of the present invention in comparison with a comparative example.

Referring to Figure 1 describes the noise reduction principle of the present invention based on the relationship between the user (M), the mobile device (3), the noise source (NS) as follows. This embodiment is an example and the actual situation may vary. For example, multiple sources of noise may be present in various locations, and the location may not be specified and may be omnidirectional.

Figure 1 (a) is a noise applied to the noise reduction method according to the embodiment of the present invention after modeling the ambient noise (N _L , N _R ) that the user hears through the earphone modeled after the estimated noise (N _L `, N <sub>R</sub> `) reverse phase (anti-phase) signal (hereinafter referred to as opposite phase signal) made in the state <sub>(/ N L`, / N</sub> R `) signals (S _L, S _R, which character original user to listen to), and Combined to provide the user through the earphone. Through this, the user M of the mobile device 3 can hear the sound of the original signal S _L , S _R , or a signal very similar to the original sound, as the sound of clean sound quality without noise.

When the noise canceling device 10 of the mobile acoustic device of the present embodiment is used, the noise source NS and various other information are used to estimate the noise (N _L , N _R ) to be heard by the user and anti-phase signal ( / N _L `, it can be transmitted to the user with a signal (S <sub>L,</sub> S <sub>R)</sub> to a chair user to hear the real / N <sub>R`).</sub> Of-phase signals output through the earpiece of the mobile device <sub>(/ N L `, / N</sub> R`) is sikimyeo offset the physical noise (N _L, N _R), Therefore, the user signal to party substantially original listening (hereinafter referred to as sound Only the signal (S _L , S _R ) can be heard. Physical noise (N _L, N _R) and the estimated noise (N _L `,` N _R) to remove noise in a noise cancellation method and apparatus by a similar performance is more excellent.

Figure 1 (b) is a comparative example of a conventional mobile device that does not use the noise removing device or method of the present embodiment described above, the noise (N _L , N _R ) generated from the noise source (NS) is the user M ) And merge with the original signal (S _L , S _R ). That is, the user hears both the ambient noise (N _L , N _R ) and the original signal S _L , S _R. Therefore, in the comparative example, the user does not have good listening to the sound, and by increasing the volume for accurate listening, the comparative example may cause the user's hearing loss, hearing loss, and the like.

In addition, in the mobile acoustic listening environment of FIGS. 1A and 1B, the mobile device 3 recognizes the ambient noise N _D flowing directly into the mobile device 3 and transmits it to the mobile device 3. It is possible to more accurately estimate the ambient noise (N _L , N _R ) flowing into the connected earphone (8).

The aforementioned mobile audio device refers to any mobile device that may have a built-in microphone or may be coupled to and output sound through earphones, and may be referred to simply as a mobile device.

The mobile device 3 is a laptop computer, a tablet PC, a wireless phone, a mobile phone, a smart phone, a smart watch, a smart glass ( smart glass, e-book reader, portable multimedia player, portable game console, navigation device, digital camera, digital multimedia broadcasting (DMB) player, digital audio recorder, digital It may have a form such as a digital audio player, a digital picture recorder, a digital picture player, a digital video recorder, a digital video player, or the like. .

The biggest difference between the noise canceling device 10 of the present embodiment and the existing noise canceling earphones is to estimate the noise encountered by the earphone user in the present embodiment. That is, the existing noise canceling earphones 'measure' the user's noise in real time using a microphone attached directly behind the earphone, but the noise canceling device implemented in this embodiment or the noise canceling method implemented by the device is the noise that the user hears. Is configured to 'estimate'.

In addition, the noise estimation for the noise removing method of the present embodiment may be applied to other methods depending on the situation. For example, the mobile device 3 may be divided into a case where a plurality of microphones are mounted so that the position of the noise source can be estimated and the position of the noise source cannot be detected by the mobile device 3. In addition, the noise estimation method may be applied to a method such as automatic setting, semi-automatic setting, manual setting. For example, when the position of the noise source can be estimated, some preset modeling forms are presented for the user to select, or when the position of the noise source cannot be estimated, the pseudo modeling form is presented and then corrected through user feedback. It can be implemented to.

If the noise source location can be estimated, after analyzing the position and characteristics of the ambient noise source using the microphones mounted on the mobile device (3), it can be used to model the noise that the user will hear. The noise reduction method including the modeling process is divided into three stages. In the first stage, the mobile device 3 analyzes the position of the surrounding sound source and the shape of the sound source and determines whether the noise is repetitive. . In the second step, the shape of the noise heard by the user through the earphone 8 in the mobile device 3 can be modeled for the repetitive noise. In the last step, an anti-phase signal of the estimated estimated noise generated by the user may be generated, and then output to the earphone 8 along with the signal originally intended by the user to be provided to the user M. have.

According to the present exemplary embodiment, the user may listen to the sound of the mobile device 3 by modeling and estimating the actual noise heard by the user M, and then the signal having the phase opposite to that of the original user M to listen to. The output may be performed together to allow the user M to hear the sound substantially free of noise.

In addition, even when the user M uses a general earphone without a microphone instead of an expensive earphone with a built-in microphone, the sound output to the general earphone 8 by using a microphone and a processor of the mobile device 3 is performed. Noise can be effectively removed. In addition, by outputting the anti-phase signal of the noise and the sound that the user wants to hear, the user M can not only remove the noise from the sound heard through the earphone 8, but also output only the anti-phase signal to the earphone 8 The user M can have a quiet environment with ambient noise removed.

In addition, in the process of estimating the actual noise heard by the user M, the hardware of the mobile device 3 causes the hardware of the ambient noise source to be changed by the amount of change of the signal acquired by the microphone of the mobile device 3 or the difference between the various sub-signals. If you can determine the location of each noise source, you can specify the location and shape of each noise source, and based on this, you can easily estimate the noise you hear, as well as hardware (processors, etc.) Even in difficult cases, in the process of estimating the actual noise heard by the user M, it is determined that the noise to be removed according to the repeatability of the corresponding sound source, and by correcting the repetitive noise through the user feedback, the user M has the earphone 8 You can effectively eliminate the noise you hear through.

2 is a flowchart illustrating a noise removing method of a mobile acoustic device according to another exemplary embodiment of the present invention.

Referring to Figure 2 describes the noise removing method according to the embodiment as follows.

First, estimate the obtained ambient noise, and the custom modeling parameters and repetitive noise that the user using the location and shape information of the noise source to hear that generates a noise _{(N L `, N R`} ) via a microphone on the mobile device (S21).

In this step (S21) it is possible to determine the location of the noise source and the type of noise generated from the noise source using at least two microphones mounted on the mobile device. Specifically, the intelligent robot and method (ETRI) capable of tracking sound sources of Korean Patent Publication No. 10-0943224 and the multi-source location tracking device of Korean Patent Publication No. 10-2011-0047870 and the method (Samsung Electronics) Reference may be made.

While the above existing technologies aim to track all sound sources occurring in the surroundings, the main purpose of the noise elimination method of the present embodiment is to find a repetitive noise source. Therefore, an additional module for analyzing the repeatability of each sound source and classifying it as noise is needed. Through such a configuration, the noise removing device of the present embodiment can grasp the position of the noise source and the shape of the noise that repeatedly generate the noise based on the mobile device. Repetitive noise referred to herein refers to noise in which waveforms in each cycle are similar to each other when the noise is cut off at a constant cycle. As a criterion for determining the similarity between the two periods, a ratio occupied in the entire period may be used for a portion where the difference in the loudness is less than or equal to a predetermined threshold.

The method of determining the location and shape of the ambient sound source to obtain the location and shape information of the repetitive noise source can use existing techniques, and can use at least two microphones mounted in the mobile device. In that case, some noise sources may be omnidirectional without specifying the direction in which they occur. Determination of repetitive noise may be determined by determining whether the corresponding noise is repeatedly generated in the same form through observation of at least several seconds. Non-repetitive noise sources are more likely to be non-noise, and even noise can be modeled and will be excluded from the noise reduction process below.

Next, to generate a noise reduction device is a custom model based on the parameter after the user model the noise to be heard, the user will hear that is opposite phase signal of noise <sub>(/ N L `, / N</sub> R`) (S22) .

In this step (S22) it is modeled how the noise detected in the above-described step (S21) is delivered to the user. For modeling noise, relative position information is needed between the mobile device measuring the noise source and the earphone located in the user's ear. Modules that can be tracked in fine units can also be attached to the earphones, but this will incur additional costs. Therefore, the user is involved to specify the relative position.

In this step (S22), the noise canceling device may use a user-defined modeling parameter, the user-defined modeling parameter is a sound effect according to the type of earphone currently used, the relative position information between the mobile device and both earphones, reverse phase Phase information for generating and the like. Both earphones include a right earphone and a left earphone belonging to a single earphone.

The information input process for the user-defined modeling parameter may be manually performed by a user in the mobile device, but is not limited thereto, and may be implemented to view or hear a result of various selection setting items given by the mobile device and to select at least one of them. Can be. In addition, this information may be updated every time the earphone is connected to the mobile device, but the present invention is not limited thereto, and the information may be stored in the memory of the mobile device in advance for frequently used specifications.

User input for custom modeling parameters, for example, can be placed parallel to the center of the user in front of the user (if it is not parallel, it can be corrected using a gyro sensor included in the mobile device) between the earphone and the mobile device. Select approximately the location of. This is possible by setting the left and right earphone gap and the vertical distance between the earphone and the mobile device. You can change these settings when you want, or you can register your favorite settings. In addition, the user may select at least one of various selection items given by the mobile device. When the relative position of the mobile device and the earphone is determined through the above example or other method, and the relative position and shape of the mobile device and the noise source are determined in the step S21, the noise is formed in the position of the earphone. You can predict what you will have.

In this modeling, not only the location information but also the sound insulation effect according to the type of earphone used by the user may be considered. For example, kernel-type earphones have more sound insulation than open earphones.

Next, the noise canceling device outputs an antiphase signal. That is, the mobile device may transmit the antiphase signal to the earphone together with the acoustic signals S _L and S _R that the user originally wants to hear (S23).

In this step (S23) outputs the anti-phase signal of the noise to be heard by the user modeled through the previous two steps (S21 and S22). Such an antiphase signal may be provided to the user in combination with a signal to be sent to the user in the mobile device. In that case, the user can hear the original wanted signal with the noise canceled out.

If the acoustic result with the noise removed is not satisfactory, the user can correct this through feedback. User feedback can be made by modifying the information needed to model the noise applied to the user. For example, the user input processed in the user feedback may include a noise source-specific position adjustment for correcting a noise generated by the omnidirectional sound from a specific location. In addition, the user input may include modifying the relative position information of the earphone and the mobile device, correcting the sound insulation effect of the earphone, and adjusting the gain for each frequency.

According to the above-described embodiment, the user can hear only the sound signal originally intended to be listened to by the antiphase signal canceled from the ambient noise among the signals finally transmitted to the earphone.

On the other hand, the process of creating the anti-phase signal of the noise that the user hears may be different from the actual because it depends on modeling. This difference can be corrected or minimized by applying feedback in a manner that the user modifies the modeling parameters if necessary.

FIG. 3 is a schematic block diagram of a mobile device equipped with the noise canceling apparatus of FIG. 1.

Referring to FIG. 3, the mobile device 3 equipped with the noise canceling device according to the present embodiment may include a processor 4 and a memory 5, and may include a peripheral device 6 according to an implementation. Peripheral device 6 may include a communication interface (I / F), an input / output system, a camera subsystem, a sensor, or a combination thereof. The noise canceling device 10 of the present embodiment may include, but is not limited to, a processor 4 and a memory 5, and further includes a specific peripheral device including a communication interface, an audio device, a microphone, or a combination thereof. It may include. The components of the mobile device 3 will be described in more detail as follows.

The processor 4 may include one or more cores, cache memory, memory interfaces, and peripheral interfaces. Multi-core refers to the integration of two or more independent cores into one package of a single integrated circuit. A single core may refer to a central processing unit. The CPU may be implemented as a system on chip (SOC) in which a micro control unit (MCU) and a peripheral device (an integrated circuit for an external expansion device) are arranged together, but is not limited thereto. The central processing unit includes a register that stores instructions to be processed, an arithmetic logical unit (ALU) that is responsible for comparison, determination, and operation, and a controller that internally controls the CPU for interpreting and executing the instructions ( control unit), internal bus, and the like.

In addition, the processor 4 may include, but is not limited to, one or more data processors, an image processor, or a codec. The data processor, image processor or codec may be configured separately. The peripheral interface connects the processor 4 to the input / output system and various other peripheral devices, and the memory interface connects the processor 4 to the memory 5.

The processor 4 of the above-described configuration may execute various software programs to perform data acquisition, data processing, and data output for the noise canceling function in the mobile audio device 3. In addition, the processor 4 may execute a specific software module (instruction set) stored in the memory 5 to perform various specific functions corresponding to the module. That is, the processor 4 may remove noise that is heard by the user from earphones connected to the mobile sound device 3 by the noise canceling module included in the software modules stored in the memory 5.

The memory 5 may be coupled to a memory interface in the processor 4. The memory 5 may include fast random access memory and / or nonvolatile memory, such as one or more magnetic disk storage devices, one or more optical storage devices and / or flash memory.

The memory 5 may also store software, programs, instruction sets, or a combination thereof. Components of the software may include an operating system module, a communication module, a graphics module, a user interface module, a moving picture experts group (MPEG) module, a camera module, one or more application modules, and the like. A module can be represented as an instruction set or program as a set of instructions.

Operating systems include built-in operating systems such as MS WINDOWS, LINUX, Darwin, RTXC, UNIX, OS X, iOS, Mac OS, VxWorks, Google OS, Android, Sea (Samsung OS), Plan 9, etc. And various components for controlling system operation of the mobile device or noise reduction device.

For general system operation or control of functions other than control of the noise canceling function, the mobile device may include, for example, memory management and control, storage hardware control and management, power control and management, and the like. The operating system described above may include, but is not limited to, a function for performing communication between various hardware (devices) and software components (modules).

The communication I / F may include one or more wireless communication subsystems. The wireless communication subsystem may include a radio frequency receiver and transceiver and / or an optical (eg, infrared) receiver or transceiver. The communication interface may be a network, for example, a Global System for Mobile Communication (GSM) network, an Enhanced Data GSM Environment (EDGE) network, a Code Division Multiple Access (CDMA) network, a W-Code Division Multiple Access (W-CDMA) network, LTE (Long Term Evolution) network, Orthogonal Frequency Division Multiple Access (OFDMA) network, WiMax network, Wireless Fidelity (Wi-Fi) network, Bluetooth network and the like can support at least one communication protocol.

The input / output system may include a touch screen controller and / or other input / output controller. The touch screen controller can be connected to the touch screen. Touch screens and touch screen controllers include, but are not limited to, capacitive, resistive, infrared and surface acoustic wave technologies as well as other proximity sensor arrangements or other elements for determining one or more contact points with the touch screen. Any multi-touch sensing technique can be used to detect contact and movement or disruption thereof.

The touch screen is a kind of display module and can function as a user interface on the mobile device 3. That is, the touch screen may transmit a user's touch input to the processor 4. The touch screen may also operate as a means and / or component for visually showing information about sound output through the earphone 8 in the mobile device 3. The visual output may be in the form of text, graphics, video, or a combination thereof.

The touch screen described above may be manufactured in any one of various display types. For example, the touch screen may include, but is not limited to, a liquid crystal display (LCD), a light emitting diode (LED), a light emitting polymer display (LPD), an organic light emitting diode (OLED), and an active matrix organic light emitting (AMOLED). It may be implemented in the form of a diode) or FLED (flexible LED).

The other input / output controller may be connected to other input / output devices mounted on or coupled to the mobile device 3. Other input / output devices may include one or more buttons, rocker switches, thumb-wheels, dials, sticks, pointer devices such as stylus, audio devices, or combinations thereof. have.

In the case of an audio device, the other input / output device may be responsible for input and / or output of an audio stream such as voice recognition, voice replication, digital recording, or a telephone function. In addition, the audio device may communicate with the user through a speaker and / or a microphone. The audio device may receive a data stream through the peripheral interface of the processor 3, convert the received data stream into an electrical stream, and then transfer the converted electric signal to a speaker or earphone. The speaker or earphone may convert and output an electric stream into a sound wave that can be heard by a human. Once the converted electrical stream is delivered, the audio device may convert the electrical stream into an audio data stream and send the converted audio data stream to the peripheral interface. A microphone refers to a means for converting sound waves transmitted from a person or other sound source into an electric stream or a component for performing a function corresponding to the means.

The sensor may include at least one selected from an illumination sensor, a gyroscope sensor, a G sensor, a motion sensor, a biometric sensor, a position sensor, or the like mounted on or coupled to the mobile device 3. The illuminance sensor detects illuminance or brightness of the outside of the device and outputs a signal (eg, a trigger signal) for a preset operation. The gyroscope sensor can recognize the up, down, left and right movements of the mobile device 3, the G sensor can be used for the automatic adjustment of the width according to the width or height of the touch screen or the screen, the motion sensor is connected to the user interface and the user It can be used to detect access or specific user input actions. The biometric sensor may include a face recognition sensor, a fingerprint recognition sensor, and the like, and the position sensor may include a global positioning system (GPS), a sound source / noise source position estimation, or a position recognition sensor. In this case, the position sensor may be connected with a plurality of microphones.

On the other hand, the above-described noise control device is not limited to the above-described configuration, but by hardware, software, or a combination thereof, including one or more stream processing and / or application specific integrated circuits (ASICs). The noise canceling operation may be performed in the mobile audio device.

4 is a schematic block diagram of an apparatus for removing noise according to another embodiment of the present invention.

Referring to FIG. 4, the noise reduction device 10 according to the present embodiment has a separate device form detachably coupled to the audio terminal 7a of the mobile device 3. The noise reduction device 10 may be detachably connected to the mobile device 3 to remove noise that a user hears through the earphone of the mobile device 3.

The mobile device 3 is a conventional device that does not have a program that implements the noise canceling method described above, a recording medium storing such a program, or a noise canceling device, but when the removable noise canceling device 10 is combined, the mobile device ( Earphones connected to 3) may have a new function of removing noise that the user hears. The mobile device 3 is similar to the mobile device described above with a processor 4a, a memory 5a, other peripherals 6, earphone terminals 7a, at least one microphone 9, at least one microphone terminal. (9a) etc. can be provided. The processor 4a and the memory 5a do not directly include a software configuration such as a module, a program or an instruction set for implementing the noise canceling method of the present embodiment, or a hardware configuration that performs a function corresponding to the software configuration. Except for the processor 4 and the memory 5 of Figure 9 may be substantially the same.

A separate removable microphone 9b may be coupled to the microphone terminal 9a. In that case, the mobile device 3 has one or more built-in microphones 9 and / or one or more removable microphones 9b and uses a time difference of arrival (TDoA) or the like to reduce noise sources. Estimate the position of.

FIG. 5 is a block diagram of a configuration that can be employed in the noise reduction device of FIG. 4.

Referring to FIG. 5, the noise canceling apparatus 10 according to the present exemplary embodiment may include a memory 50, a memory controller 57, a first connector 57, a second connector 58, and internal interfaces 59a and 59b. And a housing 60.

The memory 50 is disposed outside the mobile device 3 and includes a first module 51, a second module 52, a third module 53, a fourth module 54, and a fifth module 55. ) May be included. The first to fifth modules 51 to 55 may correspond to the input unit, the estimation unit, the generation unit, the adjustment unit, and the output unit of FIG. 7 in the following order. Of course, the memory 50 may further include at least one module corresponding to the generation unit, the repetitive noise determination unit, the modeling unit, and the pseudo signal generation unit of FIGS. 7 to 9. Since the functions and configurations of the modules 51 to 55 are substantially the same as the functions and configurations of the input unit, the estimation unit, the generation unit, the adjustment unit, and the output unit, detailed description thereof will be omitted. However, the memory 50 may be referred to as a dedicated memory to mean a memory mainly storing a module, a program, an instruction set, or a combination thereof that implements the noise canceling method to distinguish it from the memory 5 of FIG. 3.

The memory controller 57 controls the address of the storage area on the memory 50 and how to access the address, and may write or read data to a specific address of the memory 50. In addition, the memory controller 57 may perform a refresh of the memory 50, supply an operating voltage, communicate with a processor of the mobile device 3, or transmit and receive a signal.

The first connection 57 hardware-couples the noise canceling device 10 to the mobile device 3. According to the combination of the first connection unit 57, the data transmission line, the power transmission line and the audio transmission line of the noise canceling device 10 and the data transmission line, power transmission line and audio transmission line of the mobile device 3 respectively. Can be connected. In the present exemplary embodiment, the first connector 57 exemplifies one type of earphone jack which is widely used. However, the first connector 57 is not limited thereto, and any one of jacks connected to a combination of voice and data lines or a combination of voice, data and power lines may be used. The thing is not limited. For example, the first connector 57 may have a phone plug jack type, such as a 2.5TS jack, a 3.5TS jack, a 3.5TRS jack, and a 5.5TRS jack. However, of course, the first connection unit 57 may be implemented to be combined in a form such as a terminal and a fitting for the audio output terminal function of the mobile device 3.

The second connector 58 has the form of an audio female terminal. The second connector 58 may have a structure or shape substantially the same as an audio terminal coupled to a jack of an earphone in the mobile device 3. The second connector 58 may be connected to the first connector 57 through an internal bus or an internal wiring 59c, whereby the second connector 58 may be connected to an audio output terminal of the mobile device 3.

Internal interfaces 59a and 59b may include memory interface 59a and peripheral interface 59b. The memory interface 59a connects the memory 50 and the memory controller 56. The peripheral interface 59b connects the memory controller 56 and the first connector 57. The peripheral device 59b is connected to the peripheral device interface of the mobile device 3 through the first connector 57, thereby connecting the memory controller 56 and the processor of the mobile device. In this case, the first connector 57 may include a plurality of input / output terminals electrically separated from each other, some of the input / output terminals may be connected to the peripheral device interface 59b, and other portions of the input / output terminals may be connected to the internal wiring 59c. Can be.

The housing 60 is a component for supporting and protecting the memory 50, the memory controller 56, the first connector 57, the second connector 58, the internal interfaces 59a and 59b, and the like. In the present embodiment, the housing 60 may have a rectangular shape (for example, a hexahedral shape) on one side thereof, but is not limited thereto, and may have a spherical shape, a cylindrical shape, a conical shape, a tetrahedron, a polyhedron, or a combination thereof. That is, the housing 60 preferably has a size that is not thicker than the thickness of the mobile device 3 when combined with the mobile device 3 and is relatively small (eg, 1/8 or less) relative to the size of the mobile device.

For example, the size of the housing 60, except for the first connection portion 57, which protrudes outward, is about 5 mm to about 20 mm, about 5 mm in the order in which the width, length, and thickness are described based on the hexahedron shape. To about 20 mm, and about 3 mm to about 15 mm, but is not limited thereto, and may be slightly smaller or thinner than this example, and may also be slightly larger or thicker than the above example, depending on the implementation. .

6 is an exemplary view of a mobile device incorporating a noise canceling device according to another embodiment of the present invention.

Referring to FIG. 6, the noise reduction device 10 according to the present embodiment is detachably coupled to an external connection port 7c of the mobile device 3.

The mobile device 3 may include a processor 4a, a memory 5a, a peripheral device 6, an earphone terminal 7a, a cable port 7c, a microphone 9, and internal wiring. The components of the mobile device 3 may be substantially the same as the corresponding components of the other embodiments described above with reference to FIGS. 3 and 4.

The noise canceling apparatus 10 may have a memory, a memory controller, an internal interface, a third connection 7d, a microphone 7e and a housing similar to the noise canceling apparatus of FIGS. 3 and 4. The memory, memory controller, internal interface and housing may be substantially identical to the corresponding components of the noise canceling device of FIGS. 3 and 4 described above.

The third connection portion 7d is detachably coupled to the cable port 7c for the transmission of data and power. The third connection portion 7d may have a connector structure paired with the cable port 7c of the mobile device 3. For example, the third connector 7d may have a type of universal serial bus (USB) cable port of type A, type B, type C, mini-A, mini-B, micro-A or micro-B. .

The microphone 7e is installed in the noise canceling device 10 and may be detachably mounted to the mobile device 3 in addition to the microphone 9 mounted on the mobile device 3. When the microphone 7e is installed in the removable noise canceling device 10, the mobile device 3 may use at least one of the data input lines of the cable port 7c as the microphone input. In this case, the mobile device 3 may include a microphone input port in the cable port 7c in hardware, but is not limited thereto. The cable port may be changed in software by using an internal setting or an application. At least one of (7c) can be used as the microphone input port.

7 is a block diagram of a functional block that can be employed in the noise reduction apparatus according to the embodiment of the present invention.

Referring to FIG. 7, the noise canceling apparatus 10 according to the present exemplary embodiment includes an input unit 11, an estimation unit 12, a generation unit 13, an adjustment unit 14, a synthesis unit 15, and an output unit 16. ) May be included. The input unit 11, the estimating unit 12, the generating unit 13, the adjusting unit 14, the combining unit 15, and the output unit 16 may be implemented as a function module or a program mounted in a memory of the mobile device. It may be implemented by the processor of the mobile device to perform a corresponding function.

To describe each component in more detail, the input unit 11 receives ambient noise through a microphone (hereinafter, simply referred to as a microphone) of the mobile device. The input unit 11 may include an analog digital converter for converting an analog signal input through a microphone into a digital signal.

The estimator 12 estimates the noise that the user hears through the earphone in the mobile device based on the ambient noise obtained from the surroundings of the mobile device through the microphone of the mobile device. The estimator 12 may measure the noise that the user hears using the sound related parameter according to the mobile device, the user-specified modeling parameter for the mobile device, the sound related parameter according to the earphone type, or a combination thereof. The custom modeling parameter may include relative position information between the right earphone, the left earphone, and the mobile device belonging to the earphone.

In addition, the estimator 12 may determine the repetitive noise by analyzing the sound source position and the shape of the sound source of the ambient noise in the mobile device. In order to determine the repetitive noise, the estimator 12 cuts the ambient noise at regular intervals, and the acoustic section in which the waveforms of the truncated cycles are similar or the portion whose sound size difference is less than or equal to the predetermined threshold is previously selected or extracted. It can be determined whether the ratio occupies a certain percentage of the entire period of.

The generation unit 13 generates an antiphase signal of the estimated noise with respect to the noise heard by the user. When the estimator 12 determines the repetitive noise by using the filter, the generator 13 may generate a pseudo antiphase signal having an arbitrary phase and gain with respect to the repetitive noise from the estimator 12. . For example, the generation unit 13 generates an antiphase signal having an amplitude zero section in which the combination of the antiphase signal and the ambient noise in the estimation unit 12 has a certain amplitude zero section or more, or a value close to the amplitude zero for a certain section. It is possible to generate an antiphase signal by shifting or inverting the phase of the ambient noise by a half cycle or 180 degrees.

The adjusting unit 14 receives the user's feedback. The adjusting unit 14 may receive the user feedback after generating the anti-phase signal in the generating unit 13. That is, the adjuster 14 may adjust or change a parameter of the current antiphase signal or the pseudo antiphase signal in order to generate a final antiphase signal in response to a user input obtained through the user interface. The user interface may display a setting value for adjusting the position of the sound source, adjusting the relative position between the mobile device and the earphone, adjusting the earphone type, adjusting the gain for each frequency, or a combination thereof, or include an input window for user input.

The synthesizer 15 synthesizes a signal (hereinafter, referred to as an acoustic signal) that the user wants to hear through the mobile device and an antiphase signal generated by the generator 13. The synthesizing unit 15 may be implemented as a means for synthesizing two acoustic signals or a component for performing a function corresponding to such means. For example, the synthesis unit 15 may be implemented by a program execution of an processor, an electronic circuit, or a mechanical device, but is not limited thereto. Any one or more of various conventional sound synthesis methods may be used. It can be implemented using.

The output unit 16 outputs the signal synthesized by the synthesizer 15 to the earphone connected to the mobile device. In this case, the user may hear the acoustic signal from which the noise is removed through the general earphone.

In addition, the output unit 16 may output an antiphase signal through an earphone connected to a mobile device without an acoustic signal. In such a case, when the synthesizer 15 does not operate or the reverse phase signal is output to the earphone through the output unit 16 in a structure in which the synthesizer 15 is omitted, the user attaches the earphone connected to the mobile device to the ear. Just plug it in to provide a quiet environment with no noise around you.

In the present embodiment, for convenience of description, a configuration including an input unit 11, an estimation unit 12, a generation unit 12, an adjustment unit 14, a synthesis unit 15, and an output unit 16 will be described. It is not limited to this. According to the implementation of the mobile device or the noise canceling device, the adjusting unit 14 may be omitted, or the combining unit 15 or the output unit 16 may be selectively provided.

FIG. 8 is a block diagram of another embodiment of an estimator that may be employed in the apparatus for removing noise of FIG. 7.

Referring to FIG. 8, the estimation unit 12 of the noise removing apparatus according to the present embodiment includes a repetitive noise determination unit 122 and a modeling unit 124. The present embodiment may correspond to a case in which a single microphone or a small number of microphones is mounted on the mobile device, and thus it is difficult to determine the location of the noise source.

The repetitive noise determiner 122 may first classify the ambient noise obtained from the microphone by frequency, and determine whether the ambient noise classified by frequency is a repetitive noise using a filter. The filter may include one or more subfilters, and may have at least one of lowpass, bandpass, highpass, and bandstop, and may use decibels as a unit of the noise level.

The modeling unit 124 may model the type of noise that the user hears based on the ambient noise input to the mobile device with respect to the repetitive noise determined by the repetitive noise determiner 122. For modeling the noise that the user hears, the modeling unit 124 outputs a plurality of settings stored in advance with respect to the relative position between the mobile device and the earphone, and the ambient noise based on the user input information received through the user interface. The shape of the earphone can be predicted (modeled) according to its shape. For example, the modeling unit 124 may perform modeling by extracting a parameter corresponding to user input information from a lookup table or the like. The user input information may include setting information about the type of earphone or user selection information.

FIG. 9 is a partial block diagram of a modification of the noise canceling apparatus of FIG. 7.

Referring to FIG. 9, the noise removing apparatus 10 according to the present exemplary embodiment may include a repetitive noise determiner 122 and a pseudo signal generator 132. This embodiment may correspond to other embodiments of the estimator 12 and the generator 13 in the noise reduction apparatus of FIG. 7.

The repetitive noise determiner 122 may be included in the estimator 12, and the pseudo signal generator 132 may be included in the generator 13, but is not limited thereto. The noise removing device may be a separate component. 10 may be provided. The repetitive noise determiner 122 may be substantially the same as a corresponding component of the noise canceling apparatus described above with reference to FIG. 8.

The pseudo signal generator 132 generates a pseudo antiphase signal based on the repetitive noise determined by the repetitive noise determiner 122. The pseudo anti-phase signal may refer to an anti-phase signal in which the estimation of noise that the user hears through the earphone is not accurate and thus the noise cannot be removed below a certain level. In the present embodiment, the user interface provided by the pseudo signal generator 132 receives user feedback allowing phase adjustment, gain adjustment, frequency fine adjustment, and the like for the pseudo antiphase signal, and is based on one or more user feedbacks. It can be implemented to look for an antiphase signal that substantially removes noise from the pseudo antiphase signal. When user authentication is obtained for a pseudo anti-phase signal reflecting one or more user feedbacks, the pseudo signal generator 132 may be configured to provide a pseudo anti-phase signal, i.e., an anti-phase signal of noise, to the mobile device. You can output

10 is a flowchart illustrating a noise canceling method of a mobile acoustic device according to another exemplary embodiment of the present invention.

In the present embodiment, when the number of microphones mounted on the mobile device is insufficient or the diversity of directions is not enough to determine the location of the noise source, the user may be assigned to each noise after specifying the ambient sound source by frequency using the microphone of the mobile device. It describes the process of modeling the noise audible to the user by adjusting gain and phase. That is, when the location of the sound source cannot be specified in the mobile device, when the user distinguishes the ambient sound source using the frequency characteristic, the user hears the sound from which the repeated ambient noise is removed. FIG. 10 may correspond to a case in which the noise canceling method of FIG. 2 is described in more detail except for the number of microphones as a single microphone instead of a plurality of microphones.

Referring to FIG. 10, the noise canceling apparatus mounted on the mobile device first identifies a repetitive noise source by using frequency characteristics (S101), and the repetitive noise identified thereafter is a set of noise sources {n ₁ , n ₂ ,. , n _M }.

Initialize the noise modeling settings to identify repetitive noise sources. Initializing the noise modeling settings may include initializing the repetitive noise data stored in the memory. For example, k is set to 0 to initialize the noise modeling setting (S102).

Next, it is determined whether k is M (S103). According to the step S103, the user feedback module may operate for all frequency bands from k to 1.

In the above determination step (S103), if k is not M, k is increased by 1 until k is a predetermined value (M) (S104) and each noise source n _k is filtered through a band pass filter ( S105). Noise sources obtained through the microphone of the mobile device may be obtained for the right earphone and the left earphone, respectively. Then, an antiphase signal of each filtered noise source is generated (S106). The antiphase signals of each noise source can be accumulated and generated as antiphase signals for repetitive noise. The antiphase signal for repetitive noise includes an antiphase signal for repetitive noise of a right earphone (hereinafter, a right antiphase signal) (/ N _RK ) and a repetitive noise for a left earphone. Signal (hereinafter, referred to as a left antiphase signal) / N _LK .

Next, at least one or more phase adjustments, gain adjustments, and frequency fine adjustments of the right and left antiphase signals / N _RK and / N _LK are performed through the user feedback (S107). That is, in the present embodiment, the right and left antiphase signals (/ N _RK , / N _LK ) are fed back to all frequency bands of the M noise sources divided by k until k becomes a predetermined value M, thereby providing user feedback ( S107) may be repeated.

On the other hand, in the above determination step (S103), if k is M, and transmits or outputs the anti-phase signal for the repetitive noise with the signal (S _L , S _R ) that the user wants to hear (S108). The output signal output to the earphone connected to the mobile device may include a right earphone output signal NR + NE1 and a left earphone output signal NL + NE2. The right antiphase signal NE1 included in the right earphone output signal is the above-described right antiphase signal / N _RK , and the left antiphase signal NE2 included in the left earphone output signal is the above left antiphase signal ( / N _LK ), the two antiphase signals NE1 and NE2 may be identical to each other, but are not limited thereto and may have different phases, gains, frequencies, or a combination thereof. The output signals NR + NE1 and NL + NE2 are represented by Equation 1 below.

FIG. 11 is a flowchart illustrating a user feedback process used in the noise removing method of FIG. 10.

FIG. 11 may be an example of a user feedback module that may be employed in the noise canceling method of FIG. 10, in which case the noise control device of the present embodiment includes a user input for adjusting or correcting an antiphase of repetitive noise through a user interface. can do. Such a configuration may be used in various modifications of the embodiment of the present invention where user feedback is required in addition to FIG. 10.

Referring to FIG. 11, the noise reduction apparatus according to the present embodiment includes a user feedback module. The user feedback module may include an anti-phase signal generation module 13a and a user adjustment module 14a for anti-phase generation of noise. The antiphase signal generation module 13a includes at least some functional units or components of the estimator (see 12 in FIG. 2) described above, and at least some functional units or components of the generator (see 13 in FIG. 2) described above. The user adjustment module 14a may be at least some functional units or components of the above-described adjustment unit (see 14 of FIG. 2).

The anti-phase signal generation module 13a estimates an anti-phase signal of the input noise n _k (S712), and transmits the anti-phase signal of noise to the user through the earphone through the estimated anti-phase signal / n _k . (134). And with the user's approval (example of 136), the mobile device or the noise canceling device coupled to the mobile device can maintain the current noise canceling state, either alone or with an acoustic signal to listen to the antiphase signal (/ n _k ). Can be sent to the user.

On the other hand, if the user's approval for the current noise canceling state is denied (NO in 136), the noise canceling device provides a user interface for phase adjustment, gain adjustment and frequency fine adjustment to the user through the user adjustment module 14a. And adjust the phase according to the user input signal in the user interface (S74), adjust the gain (S75), or perform frequency fine tuning (S76). The output signal of the user adjustment module (14a) may be used to input noise (n _k) estimated in combination with or input noise (n _k) in place of the reverse phase signal (/ n _k) of the noise again 132.

According to the present exemplary embodiment, the phase adjustment, the gain adjustment, the frequency fine adjustment, or a combination of the antiphase signals according to the user feedback may be performed to effectively remove noise that the user hears through the earphone. In particular, in the case of using the noise canceling method or the noise canceling apparatus of the present embodiment, the user manually estimates or corrects the reverse phase of the repetitive noise according to the user's earphone usage environment, regardless of the user's various earphone usage types and earphone types. The user can effectively eliminate the repetitive noise that the user hears through the earphone. A change in the actual signal in the noise canceling method described above is illustrated in FIG. 12.

FIG. 12 is an exemplary diagram illustrating a signal in a process of estimating an antiphase signal of noise by the user feedback of FIG. 11. FIG. 12 may be a description of a process of estimating a reverse phase of a corresponding noise by receiving a user's feedback in FIG. 10, or may be an example of an actual use result of the user feedback module of FIG. 11.

The noise canceling apparatus according to the present exemplary embodiment may adjust the phase, the gain, the frequency, and the like of the antiphase signal according to a user input signal through the user interface.

First, as shown in (a) of FIG. 12, the combination signal NR + NE of the antiphase signal NE estimated based on the repetitive noise NR and the repetitive noise is similar to the repetitive noise or antiphase signal. It can be seen that it still has a repetitive noise pattern. In other words, the combination signal NR + NE of (a) fails to correctly estimate phase and gain for the antiphase signal of repetitive noise, indicating that the user is listening to the same amount or shape of noise as before.

Next, as shown in FIGS. 12B and 12C, two phases of user feedback are repeated to adjust phase and gain, and as shown in FIGS. 12D and 12E, iteratively. It can be seen that the anti-phase signal NE for the noise NR is correctly estimated so that the noise that the user hears with the earphone is almost canceled out. In this case, the combined signal NR + NE has a flat signal shape with little change in phase or gain relative to noise or antiphase signals.

According to the present embodiment, the number of phase and gain adjustments of the anti-phase signal in the user feedback is not limited, and the order of phase adjustment, gain adjustment and frequency fine adjustment are adjusted in turn until the user satisfies the noise canceling performance. Can be. In addition, if the phase and gain are adjusted to a certain degree of accuracy, the noise is reduced to a degree that the user does not feel, so the noise canceller does not always need to generate a perfectly phased antiphase signal for the noise.

The embodiments described above with reference to FIGS. 10 to 12 are more useful for a process in which a user listens to a sound from which ambient noise is removed when the mobile device is equipped with a small number of microphones or a single microphone, and thus it is impossible to estimate the location of the noise source. Do.

In particular, if the location of the noise source cannot be determined due to the small number of microphones installed in the mobile device or the insufficient diversity of directions, the user can obtain the gain and phase for each noise source after specifying the ambient sound source by frequency using the mobile device's microphone. You can adjust the frequency, frequency, etc. to model the noise you hear.

A microphone of a mobile device may be used to distinguish surrounding sound sources by frequency, and a band pass filter may be used to determine noise by each sound source of each frequency. Noise is judged based on repeatability. That is, if the noise of a specific frequency band is repeated to a certain size, it is regarded as noise. If the sound source of the frequency is determined to be noise, the anti-phase signal of the noise that the user will hear is estimated with an arbitrary phase and gain for future user adjustment. Send an arbitrary estimated antiphase signal to the user so that the user can offset the noise heard by the earphones by manually adjusting the phase and gain, and in some cases fine-tuning the frequency. do. After repeating the above process for all external sound sources separated by frequency, the anti-phase signals of all noise sources can be combined and transmitted to the user. As a result, the user can hear the sound originally intended to be noise-free.

If desired, the user can redo the process of adjusting the out-of-phase of any noise source. In addition, if there is a change in the noise source of a certain frequency, the mobile device may recommend the user to recalibrate, or recalibrate the mobile device itself according to the automatic execution setting of the pre-stored noise canceling function.

In the case of a sound listening environment that is frequently used by a user, data that stores frequency characteristics of a noise source, etc. may be used to reduce an operation time.

According to the present embodiment, due to the limitation of the mobile device, only the frequency characteristics are used to specify the ambient noise source, so that the user has much more involvement and relatively long time to set the environment compared to the method of individually identifying the location of the noise source. It can take. However, most mobile audio devices now include at least one microphone for recording, so they do not require any additional hardware and are easy to expand.

According to the above embodiments, the following effects can be obtained.

First, it is possible to effectively remove noise of a general earphone connected to a mobile device by using a processor and a microphone of the mobile device.

Second, in the process of estimating the actual noise that the user will hear, when the relative position of the mobile device and the earphone is specified, the user manually inputs the location information or listens and selects various results according to the location provided by the mobile device. This information can be registered and used to remove earphone noise.

Third, in the process of estimating the actual noise heard by the user, it can be modeled by reflecting the feedback of the user. Here, the feedback of the user may be made by modifying information necessary for modeling. For example, the feedback of the user may include location adjustment for each noise source, location adjustment between the user and the mobile device, gain, phase, and fine frequency adjustment for each identified noise source, and sound insulation effect correction for the earphone.

Fourth, in the process of estimating the actual noise to be heard by the user, if the user needs to modify the noise to be heard, such as the presence or absence of noise source, the location of the noise source can be automatically recalculated. For example, when a gyro sensor or the like is mounted on the mobile device, the location change of the mobile device may be grasped, and the noise source may be re-inspected at a predetermined time interval, thereby real-time remodeling of the noise heard by the user with the earphone.

Fifth, in the process of estimating the actual noise to be heard by the user, when hardware such as a microphone built in the mobile device cannot determine the location of the ambient noise source, each sound source divided by frequency by dividing the ambient sound source by frequency It is possible to determine whether repetitive noise with respect to the model and to remove the actual noise that the user hears through the earphone based on the determined repetitive noise.

Sixth, in the process of estimating the actual noise to be heard by the user, in consideration of the sound insulation effect according to the type of earphone currently being used, information about it can be registered and the earphone noise can be removed using the same.

Seventh, it is possible to provide an optimum noise canceling performance by estimating an antiphase signal to each user having an approximate phase and gain for each noise source divided by frequency and then sending the user to fine tune it. In this case, for each noise source with different frequencies, the user can adjust gain, phase, detail frequency, etc. while listening to the external noise and the estimated antiphase signal together until the noise is sufficiently reduced. In addition, it may be implemented to select one of several noise canceling function setting candidates heard from the mobile device.

Eighth, if there is a change in the noise source of a specific frequency, the mobile device may be implemented to encourage the user to readjust or to readjust the mobile device itself.

Ninth, the frequency characteristics of the noise source can be stored and used in advance for an environment frequently used to shorten the preparation time.

The present invention is not only applicable to all kinds of mobile devices for listening to sound, but also can use general earphones on the market, and thus can have a great impact in noise reduction function.

Meanwhile, in the above-described embodiments, the components (11 to 16, 122, 124, and 132 of FIGS. 7 to 9) of the noise canceling device of the mobile acoustic device are functional blocks or modules mounted on the mobile device or the computer device. It may be, but is not limited thereto. The aforementioned components are stored on a computer readable medium (recording medium) in the form of software for implementing a series of functions (method of noise canceling of a mobile audio device) which they perform or transmitted to a remote place in the form of a carrier for various computer devices. It may be implemented to operate. In this case, the computer readable medium may be coupled to a plurality of computer devices or cloud systems connected through a network, and at least one or more of the plurality of computer devices or cloud systems may be noise-removed from the mobile acoustic device of the present embodiment in a memory system. You can save the program or source code to perform the method.

That is, the computer readable medium may be embodied in the form of a single or combination of program instructions, data files, data structures, and the like. The programs recorded on the computer readable medium may be those specially designed and configured for the present invention, or may be known and available to those skilled in computer software.

In addition, the computer readable medium may include a hardware device that is specially configured to store and execute program instructions, such as a ROM, a RAM, a flash memory, and the like. Program instructions may include high-level language code that can be executed by a computer using an interpreter, as well as machine code such as produced by a compiler. The hardware device may be configured to operate with at least one software module to perform the noise canceling method of the present embodiment, and vice versa.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Explanation of the sign

3: mobile audio device or mobile device 4: processor

5: memory 6: peripherals

8: earphone 10: noise canceling device

11: input unit 12: estimating unit

13: generator 13a: anti-phase signal generation module

14: control unit 14a: user adjustment module

15: synthesis section 16: output section

122: repetitive noise determination unit 124: modeling unit

132: pseudo signal generator

Claims (20)

1. As a method of removing noise from a user through earphones in a noise canceling device mounted on or coupled to a mobile device,

   Receiving ambient noise through a microphone of the mobile device;

   Estimating repetitive noise heard by a user based on the noise;

   Generating an antiphase signal of the repetitive noise; And

   And outputting the anti-phase signal through an earphone connected to the mobile device.
2. The method according to claim 1,

   The estimating of the noise may include a sound related parameter according to the mobile device, a user specified modeling parameter for the mobile device, a sound related parameter according to an earphone type, or a combination thereof, wherein the user specified modeling parameter The noise canceling method of the mobile acoustic device includes relative position information between the right earphone and the left earphone and the mobile device belonging to the earphone.
3. The method according to claim 1,

   Estimating the noise,

   Determining whether the noise is repetitive by analyzing a position and a shape of the noise source of the noise obtained from the mobile device; And

   And modeling the type of noise that the user hears through the earphone connected to the mobile device with respect to the repetitive noise.

   How to reduce noise in mobile audio equipment.
4. The method according to claim 3,

   The step of determining whether the noise is a repetitive noise, after cutting the noise of a certain time interval in a certain period, the portion of the waveform of similar noise or the magnitude difference of the noise in each period is less than a certain threshold value in a certain period or more in a certain ratio How to reduce the noise of the mobile audio device.
5. The method according to claim 3,

   The modeling may include obtaining a user input through a user interface of the mobile device and predicting the shape of the noise at the position of the earphone based on the obtained user input, wherein the user input is a type of the earphone. And selection information about and relative position information between the right earphone and the left earphone belonging to the earphone and the mobile device.
6. The method according to claim 1,

   After generating the anti-phase signal, the method further includes a user feedback step of performing phase adjustment, gain adjustment, frequency fine adjustment, or a combination thereof in accordance with a user input through a user interface of the mobile device. How to remove noise of mobile audio equipment.
7. The method according to claim 6,

   The user feedback step may include the anti-phase according to a user input obtained through a user interface for adjusting the position of the sound source, adjusting the relative position between the mobile device and the earphone, adjusting the earphone type, adjusting the gain for each frequency, or a combination thereof. A noise canceling method of a mobile audio device, correcting or correcting a signal.
8. The method according to claim 1,

   The estimating of the noise may include classifying the noise by frequency and determining whether the noise by frequency is a repetitive noise using a filter.

   Generating the antiphase signal may include generating a pseudo antiphase signal having an arbitrary phase and gain by using the repetitive noise.

   How to reduce noise in mobile audio equipment.
9. The method according to claim 8,

   The generating of the anti-phase signal may include receiving a user input for the pseudo anti-phase signal through a user interface, and responsive to the user input, phase adjustment, gain adjustment, frequency fine adjustment, or a combination thereof. Noise canceling method of a mobile acoustic device, performing a combination.
10. The method according to claim 1,

    Generating the antiphase signal has an amplitude interval of less than or equal to a certain magnitude for a predetermined time or more for an estimated repetitive noise or for a composite signal of the antiphase and the estimated repetitive noise. Generating an anti-phase signal or an anti-phase signal in which the phase of the noise is shifted or inverted by 180 degrees or inverted so as to have a value close to zero amplitude for a predetermined period.
11. The method according to claim 1,

    The outputting of the antiphase signal may include outputting the antiphase signal to the earphone together with the sound signal that the user wants to hear through the mobile device, or synthesizing the antiphase signal with the sound signal. How to remove noise from sound equipment.
12. A noise control device mounted on or coupled to a mobile device to remove noise that a user hears through earphones connected to the mobile device.

    Memory to store the program: and

    A processor coupled to the memory to perform the program;

    The processor by the program,

    Receiving ambient noise through a microphone of the mobile device, estimating repetitive noise heard by a user based on the noise, generating an antiphase signal for the repetitive noise, and outputting the antiphase signal to the earphone ,

    Noise canceling device for mobile audio equipment.
13. A noise canceling device mounted on or coupled to a mobile device to remove noise that a user hears through earphones connected to the mobile device.

    An input unit configured to receive ambient noise through a microphone of the mobile device;

    An estimator estimating the repetitive noise heard by the user based on the noise;

    A generator configured to generate an anti-phase signal of the repetitive noise; And

    An output unit for outputting the anti-phase signal,

    Noise canceling device for mobile audio equipment.
14. The method according to claim 13,

    The estimator estimates the noise using a sound related parameter according to the mobile device, a user specified modeling parameter for the mobile device, a sound related parameter according to an earphone type, or a combination thereof, wherein the user specified modeling The parameter includes relative positional information between the right earphone and the left earphone belonging to the earphone and the mobile device, the type information of the earphone, or both.
15. The method according to claim 13,

    The estimating unit,

    A repetitive noise determiner for determining whether the repetitive noise is analyzed by analyzing the position and shape of the noise source with respect to the noise in the mobile device; And

    And a modeling unit for modeling a type of noise heard by the user of the earphone based on the repetitive noise.
16. The method according to claim 15,

    The repetitive noise determination unit divides the noise of a predetermined time interval into a predetermined cycle, and determines whether a portion having a similar waveform or a difference in magnitude of the noise in each cycle occupies a predetermined ratio or more in the entire cycle. ,

    Noise canceling device for mobile audio equipment.
17. The method according to claim 15,

    The modeling unit models a noise type that the user hears through the earphone based on a user input obtained through a user interface of the mobile device, wherein the user input is between a right earphone and a left earphone belonging to the earphone and the mobile device. A noise canceling device for a mobile audio device comprising relative position information, type information of the earphone, and both.
18. The method according to claim 13,

    The estimating unit includes a repeating noise determination unit for classifying the noise by frequency and determining whether the noise for each frequency is repetitive noise by using a filter.

    The generation unit may include a pseudo signal generator or an antiphase signal generation module for generating a pseudo antiphase signal having an arbitrary phase and gain by using the repetitive noise.
19. The method according to claim 18,

    An antiphase signal to output the pseudo antiphase signal to the earphone by performing phase adjustment, gain adjustment, frequency fine adjustment, or a combination thereof in response to the user input obtained through the user interface of the mobile device. The noise canceling device of the mobile audio device further comprises an adjustment unit or a user adjustment module to correct more than once.
20. The method according to claim 13,

    The apparatus may further include a synthesizer configured to output the antiphase signal to the earphone together with an acoustic signal that a user wants to hear through the mobile device, or to output the antiphase signal to the acoustic signal. Device.

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