Patent Publication Number: US-2022225449-A1

Title: Electronic device for switching communication connections according to noise environment and method for controlling the same

Description:
CROSS REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation application, claiming priority under § 365(c), of an International application No. PCT/KR2021/020009, filed on Dec. 28, 2021, which is based on and claims the benefit of a Korean patent application number 10-2021-0003876, filed on Jan. 12, 2021, in the Korean Intellectual Property Office, the disclosures of which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     1. Field 
     Certain embodiments of the disclosure relate to an electronic device for switching communication connections according to a noise environment and a method for controlling the same. 
     2. Description of Related Art 
     With digital technology advancing, electronic devices come in various types, such as smartphones, tablet personal computers (PCs), or personal digital assistants (PDAs). Electronic devices can be worn by users to enhance portability and user accessibility. 
     An electronic device may be an ear-wearable device including a pair of earphones (hereinafter, earbuds) that may be worn on the user&#39;s ears. The ear-wearable device may be connected with an external electronic device (e.g., a portable terminal). The ear-wearable device may transmit voice data to the external electronic device, and the external electronic device may transmit audio data (or audio content) to the ear-wearable device. The ear-wearable device may output the audio data (or audio content) received from the external electronic device through a speaker. 
     SUMMARY 
     Certain embodiments of the disclosure include a first electronic device, comprising at least one microphone, a communication circuit, and at least one processor, wherein the at least one processor is configured to: establish a first communication connection with an external electronic device using the communication circuit, transmit through the first communication connection, to the external electronic device, using the communication circuit, information for a first voice signal obtained using the at least one microphone, receive second noise information for a second voice signal from a second electronic device, by the communication circuit, wherein the second voice signal corresponding to the first voice signal was obtained by the second electronic device while the information for the first voice signal was transmitted to the external electronic device, and selectively transmit, based on whether first noise information for the first voice signal and the received second noise information satisfy a specified condition, first control information commanding, or for allowing the second electronic device to establish a second communication connection with the external electronic device, using the communication circuit. 
     Certain embodiments of the disclosure include a method for controlling a first electronic device. The method comprises: establishing a first communication connection with an external electronic device, using a communication circuit of the first electronic device; transmitting through the established first communication connection, to the external electronic device, using the communication circuit, information for a first voice signal obtained using at least one microphone of the first electronic device; receiving second noise information for a second voice signal from a second electronic device, using the communication circuit, wherein a second voice signal corresponding to the first voice signal is obtained by the second electronic device while the information for the first voice signal is transmitted to the external electronic device; and selectively transmitting, based on whether first noise information for the first voice signal and the received second noise information satisfy a specified condition, first control information commanding, or for allowing the second electronic device to establish a second communication connection with the external electronic device, using the communication circuit. 
     According to certain embodiments, an electronic device comprises: at least microphone; a communication circuit; and at least one processor, wherein the at least one processor is configured to: obtain a second voice signal using the at least one microphone, identify second noise information for the obtained second voice signal, transmit the identified second noise information to a first electronic device using the communication circuit, receive first control information; responsive to receiving the first control information, establish a communication connection with a second electronic device using the communication circuit based on the transmission of the second noise information, and establish a second communication connection with an external electronic device using the communication circuit, and transmit information for a voice signal obtained using the at least one microphone to the external electronic device through the established second communication connection. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram illustrating an electronic device in a network environment according to certain embodiments; 
         FIG. 2  is a block diagram illustrating a first electronic device that wirelessly receives audio data from an external electronic device, according to certain embodiments; 
         FIG. 3  is a block diagram illustrating a first external electronic device storing at least one electronic device, according to certain embodiments; 
         FIG. 4  is a view illustrating a first electronic device, a second electronic device, and/or an external electronic device in a wireless communication environment, according to certain embodiments; 
         FIG. 5A  is a flowchart illustrating a method in which a first electronic device controls a communication connection of a second electronic device by comparing noise at the first electronic device with noise at the second electronic device, according to certain embodiments; 
         FIG. 5B  is a view illustrating a method in which a first electronic device controls a communication connection of a second electronic device by comparing noise at the first electronic device with noise at the second electronic device, according to certain embodiments; 
         FIG. 6  is a flowchart illustrating a method in which a first electronic device transmits first control information to control a communication connection of a second electronic device by comparing noise at the first electronic device with noise at the second electronic device, according to certain embodiments; 
         FIG. 7  is a flowchart illustrating a method in which a first electronic device provides information about noise at the first electronic device to a second electronic device after releasing a communication connection with an external electronic device, according to certain embodiments; 
         FIG. 8A  is a flowchart illustrating a method in which a first electronic device re-establishes a communication connection with an external electronic device, according to certain embodiments; 
         FIG. 8B  is a view illustrating a method in which a first electronic device re-establishes a communication connection with an external electronic device, according to certain embodiments; 
         FIG. 9  is a view illustrating a method for maintaining or changing a setting of a master device according to comparison of noise at a first and second electronic device, performed in each preset period, according to certain embodiments; 
         FIG. 10  is a flowchart illustrating a method for operating a pair of earbuds, according to certain embodiments; and 
         FIG. 11  illustrates an example of a screen that may be displayed on a display of an external electronic device according to certain embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Earbuds may provide various functions. For example, each earbud may include a microphone to detect the user&#39;s voice and thus transmit data representing the user&#39;s voice to an external electronic device (e.g., a portable terminal). 
     An ear-wearable device composed of a pair of earbuds may be, e.g., a true wireless stereo (TWS) headset. The earbuds constituting the TWS headset may be wirelessly communicatively connected with each other. The microphone of one of the pair of earbuds may be used as the main microphone (MIC), and data for the user&#39;s voice detected through the main microphone may be transmitted to the external electronic device (e.g., a portable terminal). 
     If an external voice is detected in a noise environment, not only the user&#39;s voice but also noise from the ambient environment may be introduced with the voice through the microphone. In this case, the level of noise that may be detected by the microphone of each earbud may be different. For example, directional noise, such as wind, may cause relatively more noise to one earbud and may cause relatively less noise to the other earbud. If the main microphone for detecting the user&#39;s voice is fixed, a lot of noise may be introduced with the voice, so that the quality of the call through the user&#39;s voice may be degraded. 
     According to certain embodiments, there may be provided an electronic device for setting and/or changing a microphone to be used as a main microphone by identifying noise for each earbud and a method for controlling the same. 
     According to certain embodiments, there may be provided an electronic device for establishing or releasing a communication connection with an external electronic device to set and/or change a microphone to be used as a main microphone and a method for controlling the same. 
     According to certain embodiments, the electronic device may compare noises for the earbuds with each other and detect the user&#39;s voice through the microphone of the earbuds less influenced by the noise, thereby providing enhanced call quality. 
     Various effects achievable according to the disclosure are not limited by the foregoing effects. 
       FIG. 1  describes an electronic device wherein certain embodiments can be practiced. One or more electronic devices  102  may be wearable electronic devices such as earbuds. According to certain embodiments, the electronic device may compare noises for the earbuds with each other and detect the user&#39;s voice through the microphone of the earbuds less influenced by the noise, thereby providing enhanced call quality. Data for the user&#39;s voice detected through the main microphone may be transmitted to the external electronic device (e.g., a portable terminal). 
       FIG. 1  is a block diagram illustrating an electronic device  101  in a network environment  100  according to certain embodiments. Referring to  FIG. 1 , the electronic device  101  in the network environment  100  may communicate with at least one of an electronic device  102  via a first network  198  (e.g., a short-range wireless communication network), or an electronic device  104  or a server  108  via a second network  199  (e.g., a long-range wireless communication network). According to an embodiment, the electronic device  101  may communicate with the electronic device  104  via the server  108 . According to an embodiment, the electronic device  101  may include a processor  120 , memory  130 , an input module  150 , a sound output module  155 , a display module  160 , an audio module  170 , a sensor module  176 , an interface  177 , a connecting terminal  178 , a haptic module  179 , a camera module  180 , a power management module  188 , a battery  189 , a communication module  190 , a subscriber identification module (SIM)  196 , or an antenna module  197 . In some embodiments, at least one (e.g., the connecting terminal  178 ) of the components may be omitted from the electronic device  101 , or one or more other components may be added in the electronic device  101 . According to an embodiment, some (e.g., the sensor module  176 , the camera module  180 , or the antenna module  197 ) of the components may be integrated into a single component (e.g., the display module  160 ). 
     The processor  120  may execute, for example, software (e.g., a program  140 ) to control at least one other component (e.g., a hardware or software component) of the electronic device  101  coupled with the processor  120 , and may perform various data processing or computation. According to one embodiment, as at least part of the data processing or computation, the processor  120  may store a command or data received from another component (e.g., the sensor module  176  or the communication module  190 ) in volatile memory  132 , process the command or the data stored in the volatile memory  132 , and store resulting data in non-volatile memory  134 . According to an embodiment, the processor  120  may include a main processor  121  (e.g., a central processing unit (CPU) or an application processor (AP)), or an auxiliary processor  123  (e.g., a graphics processing unit (GPU), a neural processing unit (NPU), an image signal processor (ISP), a sensor hub processor, or a communication processor (CP)) that is operable independently from, or in conjunction with, the main processor  121 . For example, when the electronic device  101  includes the main processor  121  and the auxiliary processor  123 , the auxiliary processor  123  may be configured to use lower power than the main processor  121  or to be specified for a designated function. The auxiliary processor  123  may be implemented as separate from, or as part of the main processor  121 . 
     The term “processor” as used in this document shall be understood to refer to both the singular and plural contexts. 
     The auxiliary processor  123  may control at least some of functions or states related to at least one component (e.g., the display module  160 , the sensor module  176 , or the communication module  190 ) among the components of the electronic device  101 , instead of the main processor  121  while the main processor  121  is in an inactive (e.g., sleep) state, or together with the main processor  121  while the main processor  121  is in an active state (e.g., executing an application). According to an embodiment, the auxiliary processor  123  (e.g., an image signal processor or a communication processor) may be implemented as part of another component (e.g., the camera module  180  or the communication module  190 ) functionally related to the auxiliary processor  123 . According to an embodiment, the auxiliary processor  123  (e.g., the neural processing unit) may include a hardware structure specified for artificial intelligence model processing. The artificial intelligence model may be generated via machine learning. Such learning may be performed, e.g., by the electronic device  101  where the artificial intelligence is performed or via a separate server (e.g., the server  108 ). Learning algorithms may include, but are not limited to, e.g., supervised learning, unsupervised learning, semi-supervised learning, or reinforcement learning. The artificial intelligence model may include a plurality of artificial neural network layers. The artificial neural network may be a deep neural network (DNN), a convolutional neural network (CNN), a recurrent neural network (RNN), a restricted Boltzmann machine (RBM), a deep belief network (DBN), a bidirectional recurrent deep neural network (BRDNN), deep Q-network or a combination of two or more thereof but is not limited thereto. The artificial intelligence model may, additionally or alternatively, include a software structure other than the hardware structure. 
     The memory  130  may store various data used by at least one component (e.g., the processor  120  or the sensor module  176 ) of the electronic device  101 . The various data may include, for example, software (e.g., the program  140 ) and input data or output data for a command related thereto. The memory  130  may include the volatile memory  132  or the non-volatile memory  134 . 
     The program  140  may be stored in the memory  130  as software, and may include, for example, an operating system (OS)  142 , middleware  144 , or an application  146 . 
     The input module  150  may receive a command or data to be used by other component (e.g., the processor  120 ) of the electronic device  101 , from the outside (e.g., a user) of the electronic device  101 . The input module  150  may include, for example, a microphone, a mouse, a keyboard, keys (e.g., buttons), or a digital pen (e.g., a stylus pen). 
     The sound output module  155  may output sound signals to the outside of the electronic device  101 . The sound output module  155  may include, for example, a speaker or a receiver. The speaker may be used for general purposes, such as playing multimedia or playing record. The receiver may be used for receiving incoming calls. According to an embodiment, the receiver may be implemented as separate from, or as part of the speaker. 
     The display module  160  may visually provide information to the outside (e.g., a user) of the electronic device  101 . The display  160  may include, for example, a display, a hologram device, or a projector and control circuitry to control a corresponding one of the display, hologram device, and projector. According to an embodiment, the display  160  may include a touch sensor configured to detect a touch, or a pressure sensor configured to measure the intensity of a force generated by the touch. 
     The audio module  170  may convert a sound into an electrical signal and vice versa. According to an embodiment, the audio module  170  may obtain the sound via the input module  150 , or output the sound via the sound output module  155  or a headphone of an external electronic device (e.g., an electronic device  102 ) directly (e.g., wiredly) or wirelessly coupled with the electronic device  101 . 
     The sensor module  176  may detect an operational state (e.g., power or temperature) of the electronic device  101  or an environmental state (e.g., a state of a user) external to the electronic device  101 , and then generate an electrical signal or data value corresponding to the detected state. According to an embodiment, the sensor module  176  may include, for example, a gesture sensor, a gyro sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) sensor, a biometric sensor, a temperature sensor, a humidity sensor, or an illuminance sensor. 
     The interface  177  may support one or more specified protocols to be used for the electronic device  101  to be coupled with the external electronic device (e.g., the electronic device  102 ) directly (e.g., wiredly) or wirelessly. According to an embodiment, the interface  177  may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface, or an audio interface. 
     A connecting terminal  178  may include a connector via which the electronic device  101  may be physically connected with the external electronic device (e.g., the electronic device  102 ). According to an embodiment, the connecting terminal  178  may include, for example, a HDMI connector, a USB connector, a SD card connector, or an audio connector (e.g., a headphone connector). 
     The haptic module  179  may convert an electrical signal into a mechanical stimulus (e.g., a vibration or motion) or electrical stimulus which may be recognized by a user via his tactile sensation or kinesthetic sensation. According to an embodiment, the haptic module  179  may include, for example, a motor, a piezoelectric element, or an electric stimulator. 
     The camera module  180  may capture a still image or moving images. According to an embodiment, the camera module  180  may include one or more lenses, image sensors, image signal processors, or flashes. 
     The power management module  188  may manage power supplied to the electronic device  101 . According to one embodiment, the power management module  188  may be implemented as at least part of, for example, a power management integrated circuit (PMIC). 
     The battery  189  may supply power to at least one component of the electronic device  101 . According to an embodiment, the battery  189  may include, for example, a primary cell which is not rechargeable, a secondary cell which is rechargeable, or a fuel cell. 
     The communication module  190  may support establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device  101  and the external electronic device (e.g., the electronic device  102 , the electronic device  104 , or the server  108 ) and performing communication via the established communication channel. The communication module  190  may include one or more communication processors that are operable independently from the processor  120  (e.g., the application processor (AP)) and supports a direct (e.g., wired) communication or a wireless communication. According to an embodiment, the communication module  190  may include a wireless communication module  192  (e.g., a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module  194  (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). A corresponding one of these communication modules may communicate with the external electronic device  104  via a first network  198  (e.g., a short-range communication network, such as Bluetooth™, wireless-fidelity (Wi-Fi) direct, or infrared data association (IrDA)) or a second network  199  (e.g., a long-range communication network, such as a legacy cellular network, a 5G network, a next-generation communication network, the Internet, or a computer network (e.g., local area network (LAN) or wide area network (WAN)). These various types of communication modules may be implemented as a single component (e.g., a single chip), or may be implemented as multi components (e.g., multi chips) separate from each other. The wireless communication module  192  may identify or authenticate the electronic device  101  in a communication network, such as the first network  198  or the second network  199 , using subscriber information (e.g., international mobile subscriber identity (IMSI)) stored in the subscriber identification module  196 . 
     The wireless communication module  192  may support a 5G network, after a 4G network, and next-generation communication technology, e.g., new radio (NR) access technology. The NR access technology may support enhanced mobile broadband (eMBB), massive machine type communications (mMTC), or ultra-reliable and low-latency communications (URLLC). The wireless communication module  192  may support a high-frequency band (e.g., the mmWave band) to achieve, e.g., a high data transmission rate. The wireless communication module  192  may support various technologies for securing performance on a high-frequency band, such as, e.g., beamforming, massive multiple-input and multiple-output (massive MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, or large scale antenna. The wireless communication module  192  may support various requirements specified in the electronic device  101 , an external electronic device (e.g., the electronic device  104 ), or a network system (e.g., the second network  199 ). According to an embodiment, the wireless communication module  192  may support a peak data rate (e.g., 20 Gbps or more) for implementing eMBB, loss coverage (e.g., 164 dB or less) for implementing mMTC, or U-plane latency (e.g., 0.5 ms or less for each of downlink (DL) and uplink (UL), or a round trip of 1 ms or less) for implementing URLLC. 
     The antenna module  197  may transmit or receive a signal or power to or from the outside (e.g., the external electronic device). According to an embodiment, the antenna module  197  may include one antenna including a radiator formed of a conductor or conductive pattern formed on a substrate (e.g., a printed circuit board (PCB)). According to an embodiment, the antenna module  197  may include a plurality of antennas (e.g., an antenna array). In this case, at least one antenna appropriate for a communication scheme used in a communication network, such as the first network  198  or the second network  199 , may be selected from the plurality of antennas by, e.g., the communication module  190 . The signal or the power may then be transmitted or received between the communication module  190  and the external electronic device via the selected at least one antenna. According to an embodiment, other parts (e.g., radio frequency integrated circuit (RFIC)) than the radiator may be further formed as part of the antenna module  197 . 
     The antenna module  197  may form a mmWave antenna module. According to an embodiment, the mmWave antenna module may include a printed circuit board, a RFIC disposed on a first surface (e.g., the bottom surface) of the printed circuit board, or adjacent to the first surface and capable of supporting a designated high-frequency band (e.g., the mmWave band), and a plurality of antennas (e.g., array antennas) disposed on a second surface (e.g., the top or a side surface) of the printed circuit board, or adjacent to the second surface and capable of transmitting or receiving signals of the designated high-frequency band. 
     At least some of the above-described components may be coupled mutually and communicate signals (e.g., commands or data) therebetween via an inter-peripheral communication scheme (e.g., a bus, general purpose input and output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI)). 
     According to an embodiment, commands or data may be transmitted or received between the electronic device  101  and the external electronic device  104  via the server  108  coupled with the second network  199 . The external electronic devices  102  or  104  each may be a device of the same or a different type from the electronic device  101 . According to an embodiment, all or some of operations to be executed at the electronic device  101  may be executed at one or more of the external electronic devices  102 ,  104 , or  108 . For example, if the electronic device  101  should perform a function or a service automatically, or in response to a request from a user or another device, the electronic device  101 , instead of, or in addition to, executing the function or the service, may request the one or more external electronic devices to perform at least part of the function or the service. The one or more external electronic devices receiving the request may perform the at least part of the function or the service requested, or an additional function or an additional service related to the request, and transfer an outcome of the performing to the electronic device  101 . The electronic device  101  may provide the outcome, with or without further processing of the outcome, as at least part of a reply to the request. To that end, a cloud computing, distributed computing, mobile edge computing (MEC), or client-server computing technology may be used, for example. The electronic device  101  may provide ultra-low-latency services using, e.g., distributed computing or mobile edge computing. In another embodiment, the external electronic device  104  may include an internet-of-things (IoT) device. The server  108  may be an intelligent server using machine learning and/or a neural network. According to an embodiment, the external electronic device  104  or the server  108  may be included in the second network  199 . The electronic device  101  may be applied to intelligent services (e.g., smart home, smart city, smart car, or health-care) based on 5G communication technology or IoT-related technology. 
     As noted above, electronic devices  102  can be earbuds with microphones. If an external voice is detected in a noise environment, not only the user&#39;s voice but also noise from the ambient environment may be introduced with the voice through the microphone. In this case, the level of noise that may be detected by the microphone of each earbud may be different. For example, directional noise, such as wind, may cause relatively more noise to one earbud and may cause relatively less noise to the other earbud. If the main microphone for detecting the user&#39;s voice is fixed, a lot of noise may be introduced with the voice, so that the quality of the call through the user&#39;s voice may be degraded. 
     In  FIG. 2 , electronic device  201  establishes communication with a portable electronic device  205  and a second electronic device  202 . The electronic device  201  can correspond to a first earbud and the second electronic device  202  can correspond to a second earbud. The electronic device  201  includes a microphone  242  that obtains a voice signal. The second electronic device  202  obtains the voice signal from a different vantage point. The electronic device  201  receives the noise information from the second electronic device  202 . Based on the noise information from the voice signal received at the first electronic device  201  and the noise information received from the second electronic device  202 , electronic device  201  transmits control information commanding, or for allowing the second electronic device  202  to establish a communication connection to electronic device  205 . 
       FIG. 2  is a block diagram illustrating a first electronic device  201  (e.g., electronic device  102  of  FIG. 1 ) communicating with a second external electronic device  205  (e.g., the electronic device  101  of  FIG. 1 ). 
     When the first electronic device  201  is communicatively connected with the second electronic device  202 , the first electronic device  201  may become a master device and the second electronic device  202  may become a slave device. The first electronic device  201  serving as the master device may establish a communication connection with the second external electronic device  205  and receive data (e.g., an audio signal) from the second external electronic device  205  through the established communication connection. The first electronic device  201  serving as the master device may transmit voice data (e.g., information about a voice signal) to the second external electronic device  205  through the established communication connection. 
     The second electronic device  202  serving as the slave device does not establish a communication connection with the second external electronic device  205  and may obtain data (e.g., an audio signal) transmitted by the second external electronic device  205 . For example, the second electronic device  202  as a slave device may obtain the data (e.g., an audio signal) transmitted by the second external electronic device  205  by receiving the data (e.g., an audio signal), from the second external electronic device  205  via the first electronic device  201 . The second electronic device  202  may also receive the data by identifying (e.g., sniffing) the data (e.g., an audio signal) transmitted by the second external electronic device  205  using connection information for the communication connection formed between the first electronic device  201  and the second external electronic device  205 . The second electronic device  202  serving as the slave device may also establish a communication connection with the second external electronic device  205  and may also receive data (e.g., an audio signal) from the second external electronic device  205  through the established communication connection. 
     When the first electronic device  201  is communicatively connected with the second electronic device  202 , the first electronic device  201  may become a slave device and the second electronic device  202  may become a master device. A method for determining the first electronic device  201  and the second electronic device  202  as a master device or a slave device or a method for changing (e.g., switching) to a master device or slave device is described below in more detail with reference to the drawings. 
     The first electronic device  201  may include the same or similar components to at least one of the components (e.g., modules) of the electronic device  101  illustrated in  FIG. 1 . The first electronic device  201  may be the external electronic device  102  of  FIG. 1  or the external electronic device  104  of  FIG. 1 . The first electronic device  201  may include an antenna module  211  (e.g., the antenna module  197  of  FIG. 1 ), a communication module  210  (e.g., the communication module  190  of  FIG. 1 ), an input device  220  (e.g., the input device  150  of  FIG. 1 ), a sensor module  230  (e.g., the sensor module  176  of  FIG. 1 ), an audio processing module  240  (e.g., the audio module  170  of  FIG. 1 ), a memory  250  (e.g., the memory  130  of  FIG. 1 ), a power management module  260  (e.g., the power management module  188  of  FIG. 1 ), a battery  270  (e.g., the battery  189  of  FIG. 1 ), an interface  280  (e.g., the interface  177  of  FIG. 1 ), and a processor  290  (e.g., the processor  120  of  FIG. 1 ). 
     The microphone  242  may include at least one air conduction microphone and/or at least one bone conduction microphone for detecting voice. The air conduction microphone may detect the voice (e.g., the user&#39;s utterance) transferred through air and output a voice signal corresponding to the detected voice. The bone conduction microphone may measure the vibration of the user&#39;s bone (e.g., skull) due to the user&#39;s utterance and may output a voice signal corresponding to the measured vibration. The bone conduction microphone may be referred to as a bone conduction sensor or in other various terms. The voice detected by the air conduction microphone is a voice mixed with external noise while the user&#39;s utterance is transferred through the air, whereas the voice detected by the bone conduction microphone may be mixed with less noise (e.g., influence by noise) because it is detected from the vibration of the bone. Therefore, the bone conduction microphone may output a voice signal corresponding to the user&#39;s voice with reduced external noise even in a high-noise environment. Moreover, noise information can be deduced by comparing the voice signal from the bone conduction microphone and the voice signal received from the air conduction microphone, such as subtracting. The voice signal output from the microphone  242  may be transferred to the processor  290 . An acceleration sensor (e.g., the sensor module  230 ) may be used to obtain a voice signal corresponding to the user&#39;s voice with reduced external noise. For example, the acceleration sensor may measure the vibration of the user&#39;s skin due to the user&#39;s voice utterance and output a voice signal corresponding to the measured vibration to the processor  290 . Since the voice (e.g., vibration) detected by the acceleration sensor is detected from the vibration of the skin, the inflow of external noise (e.g., the influence by noise) may be small. The above-described bone conduction microphone and/or acceleration sensor may be referred to as a voice pickup unit (VPU) or may be referred to in other various terms. 
     The communication module  210  may include a wireless communication module (e.g., a cellular communication module, a wireless-fidelity (Wi-Fi) communication module, a Bluetooth communication module, a near-field communication (NFC) communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). A corresponding communication module among these communication modules may communicate with at least one of a first external electronic device  204  (e.g., a charger), a second external electronic device  205  (e.g., a portable terminal), or a second electronic device  202  through a first network (e.g., the first network  198  of  FIG. 1 ) or a second network (e.g., the second network  199  of  FIG. 1 ). The second electronic device  202  may be an earbud configured in pair with the first electronic device  201 . The communication module  210  may include one or more communication processors that are operable independently from the processor  290  and supports a direct (e.g., wired) communication or a wireless communication. 
     The antenna module  211  may transmit a signal or power to, or receive a signal or power from, another electronic device (e.g., the external electronic device  204  or  205  or the second electronic device  202 ). The antenna module  211  may include one antenna including a radiator formed of a conductor or conductive pattern formed on a substrate (e.g., a printed circuit board (PCB)). The antenna module  211  may include a plurality of antennas. In this case, at least one antenna appropriate for a communication scheme used in a communication network, such as the first network (e.g., the first network  198  of  FIG. 1 ) or the second network (e.g., the second network  199  of  FIG. 2 ), may be selected from the plurality of antennas by, e.g., the communication module  210 . The signal or the power may then be transmitted or received between the communication module  210  and another electronic device via the selected at least one antenna. According to an embodiment, other parts (e.g., radio frequency integrated circuit (RFIC)) than the radiator may be further formed as part of the antenna module  211 . 
     The antenna module  211  may include at least one of a coil, where current may be induced by a magnetic field, a resonator, where a resonance phenomenon is generated by a magnetic field having a specific resonant frequency, or a plurality of patch antennas for receiving electromagnetic waves, to wirelessly receive power from another electronic device (e.g., the external electronic device  204  or  205  or the second electronic device  202 ). 
     The input device  220  may be configured to generate various input signals required to operate the first electronic device  201 . The input device  220  may include a touch pad, a touch panel, or a button. The touch pad may recognize touch inputs in at least one of capacitive, resistive, infrared, or ultrasonic methods. If a capacitive touch pad is provided, physical contact or proximity recognition may be possible. The touch pad may further include a tactile layer. The touch pad including the tactile layer may provide a tactile response to the user. The button may include, e.g., a physical button or an optical key. 
     The input device  220  may generate a user input regarding the turn-on/off of the first electronic device  201 . The input device  220  may receive a user input for a communication connection between the first electronic device  201  and the second external electronic device  205 . The input device  220  may receive a user input associated with audio data (or audio content). For example, the user input may be associated with functions of starting playback of audio data, pausing playback, stopping playback, adjusting playback speed, adjusting playback volume, or muting. The operation of the first electronic device  201  may be controlled by various gestures, such as tapping or swiping up/down the surface on which the touch pad is installed. If a gesture related to a single tap is detected through the input device  220 , the first electronic device  201  (or the processor  290 ) plays or pause the playback of audio data. If a gesture related to a double tap is detected through the input device  220 , the first electronic device  201  may switch the playback to the next audio data. If a gesture related to a triple tap is detected through the input device  220 , the first electronic device  201  may switch the playback to the previous audio data. According to an embodiment, if a gesture of swiping up or down is detected through the input device  220 , the first electronic device  201  may adjust the volume related to the playback of audio data. If a gesture related to a double tap is detected through the input device  220  when an incoming call is received, the first electronic device  201  may connect the call. 
     The sensor module  230  may measure a physical quantity or detect an operational state of the first electronic device  201 . The sensor module  230  may convert the measured or detected information into an electrical signal. The sensor module  230  may include, e.g., an acceleration sensor, a gyro sensor, a geomagnetic sensor, a magnetic sensor, a proximity sensor, a gesture sensor, a grip sensor, or a biometric sensor. According to an embodiment, the first electronic device  201  may further include an optical sensor. The optical sensor may include a light emitting unit (e.g., a light emitting diode (LED)) that outputs light of at least one wavelength band. The optical sensor may include a light receiving unit (e.g., a photodiode) that receives light of one or more wavelength bands scattered or reflected from an object and generates an electrical signal. 
     The audio processing module  240  may support an audio data gathering function. The audio processing module  240  may play the gathered audio data. According to an embodiment, the audio processing module  240  may include an audio decoder (not shown) and a D/A converter (not shown). The audio decoder may convert audio data stored in the memory  250  into a digital audio signal. The D/A converter may convert the digital audio signal converted by the audio decoder into an analog audio signal. The audio decoder may convert audio data received from the second external electronic device  205  through the communication module  210  and stored in the memory  250  into a digital audio signal. The speaker  241  may output the analog audio signal converted by the D/A converter. According to an embodiment, the audio processing module  240  may include an A/D converter (not shown). The A/D converter may convert the analog audio signal transferred through the microphone  242  into a digital voice signal. 
     The audio processing module  240  may play various audio data set in the operation of the first electronic device  201 . For example, if it is detected that the first electronic device  201  is plugged or unplugged into/from an ear, the audio processing module  240  may be designed to play audio data related to a corresponding effect or guide sound. According to certain embodiments, if it is detected that the first electronic device  201  is coupled to, or decoupled from, the first external electronic device  204 , the audio processing module  240  may be designed to play audio data related to a corresponding effect or guide sound. The output of the sound effect or guide sound may be omitted according to the user setting or the designer&#39;s intention. The audio processing module  240  may be designed to be included in the processor  290 . 
     The memory  250  may store various data used by at least one component (e.g., the processor  290  or a sensor module  230 ) of the electronic device  201 . The various data may include, for example, software and input data or output data for a command related thereto. The memory  250  may include a volatile memory or a non-volatile memory. 
     The memory  250  may include a non-volatile memory that stores the first audio data (non-volatile audio data) received from the second external electronic device  205 . The memory  250  may include a volatile memory that stores second audio data (e.g., volatile audio data) received from the second external electronic device  205 . 
     The memory  250  may store local address information, peer address information, and authentication address information. The local address information for the first electronic device  201  may indicate a Bluetooth device address (e.g., BD_ADDR) of the first electronic device  201 , and peer address information for the first electronic device  201  may indicate the Bluetooth device address of the counterpart device (e.g., the second electronic device  202 ) configured in pair with the first electronic device  201  in the Bluetooth network. The local address information and the peer address information for the first electronic device  201  may be used for a communication connection between the first electronic device  201  and a counterpart device (e.g., the second electronic device  202 ) configured in pair or for communication connection with the second external electronic device  205 . The local address information or the peer address information may be in the form of a 6-byte Bluetooth device address (e.g., BD_ADDR) or LE address information generated based on the Bluetooth device address. The authentication address information for the first electronic device  201  may be address information for the first external electronic device  204  for storing the first electronic device  201  and may include communication address information (e.g., MAC address or Bluetooth address) of the first external electronic device  301  or unique identification information, such as a serial number set by the manufacturer of the first external electronic device  301 , and may be set in the first electronic device  201 . The initial state of the first electronic device  201  may include a state in which authentication address information is not set. 
     The power management module  260  may manage power supplied to the first electronic device  201 . The power management module  260  may be implemented as at least part of, for example, a PMIC. The power management module  260  may include a battery charging module. If another electronic device (e.g., the external electronic device  204  or  205  or the second electronic device  202 ) is electrically connected with the first electronic device  201  (wirelessly or wiredly), the power management module  260  may receive power from the other electronic device to charge the battery  270 . If the first electronic device  201  is inserted into the first external electronic device  204 , with the first electronic device  201  powered off, the first electronic device  201  may power on the first electronic device  201  or turn on at least part of the communication module  210  based on the power received from the other electronic device. 
     The battery  270  may supply power to at least one component of the first electronic device  201 . The battery  270  may include, for example, a primary cell which is not rechargeable, a secondary cell which is rechargeable, or a fuel cell. If the first electronic device  201  is inserted into the first external electronic device  204 , the first electronic device  201  may charge the battery  270  to a previously designated charge level and then power on the first electronic device  201  or turn on at least part of the communication module  210 . 
     The interface  280  may support one or more specified protocols to be used for the first electronic device  201  to be coupled with the external electronic device  204  or  205  directly (e.g., wiredly) or wirelessly. The interface  280  may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface, or an audio interface. The interface  280  may include a connecting terminal for forming a physical connection with the first external electronic device  204 . 
     The first electronic device  201  may include a display device (not shown). The display device may be configured to provide various screen interfaces required for operation of the first electronic device  201 . The display device may provide the user interface related to the play of audio data. The display device may provide a user interface related to a function of receiving audio data from the second external electronic device  205  or a function of transmitting audio data to the second external electronic device  205 . The display device may include a light emitting means, such as an LED. For example, the light emitting means may be controlled to emit a color of light corresponding to charging or completion of charging. For example, if the first electronic device  201  is communicatively connected with the second external electronic device  205 , the light emitting means may be controlled to emit a specific color of light. For example, the light emitting means may be controlled to emit a specific color of light depending on the playing state of the audio data (e.g., during play or pause). For example, the light emitting means may be controlled to emit a specific color of light according to a user input generated through the input device. 
     The processor  290  may execute, e.g., software to control at least one other component (e.g., a hardware or software component) of the first electronic device  201  connected with the processor  290  and may process or compute various data. As at least part of the data processing or computation, the processor  290  may load a command or data received from another component (e.g., the sensor module  230  or communication module  210 ) onto a volatile memory  250 , process the command or the data stored in the volatile memory, and store resulting data in a non-volatile memory. 
     The processor  290  may identify whether an electrical connection is formed between the first electronic device  201  and the first external electronic device  204  through the sensor module  230  or the interface  280 . The processor  290  may recognize a magnet installed in the first external electronic device  204  through a magnetic sensor (e.g., a hall sensor) included in the sensor module  230 , thereby identifying whether an electrical connection is formed between the first electronic device  201  and the first external electronic device  204 . The processor  290  may recognize that the connecting terminal included in the interface  280  contacts the connecting terminal installed in a mounting part of the first external electronic device  204 , thus identifying whether an electrical connection is formed between the first electronic device  201  and the first external electronic device  204 . The processor  290  may identify whether the first electronic device  201  is worn on the ear through the sensor module  230 . 
     The first electronic device  201  may further include various modules depending on the form in which it is provided. There are many variations according to the convergence trend of digital devices, so it is not possible to list them all, but components equivalent to the above-mentioned components may be further included in the first electronic device  201 . Further, it is apparent that in the first electronic device  201  according to an embodiment, specific components may be excluded from the above components or replaced with other components according to the form in which it is provided. This will be easily understood by those of ordinary skill in the art. 
     The second electronic device  202  configured in pair with the first electronic device  201  may include the same components as those included in the first electronic device  201  and may perform all or some of the operations of the first electronic device  201  described below in connection with the drawings. 
     Operations described in the disclosure may be operations performed by the processor  290  of the first electronic device  201  or the second electronic device  202  unless otherwise specified. 
       FIG. 3  is a block diagram illustrating a first external electronic device  301  (e.g., the first external electronic device  204  of  FIG. 2 ) storing at least one electronic device (e.g., the first electronic device  201  and/or the second electronic device  202  of  FIG. 2 ) according to certain embodiments. 
     The first external electronic device  301  may be a case device for storing the first electronic device  201  and the second electronic device  202 . The first external electronic device  301  may include a processor  310 , an antenna module  321 , a communication module  320 , a sensor module  330 , at least one charging indicator  335 , an input device  340 , an electronic device interface  345 , a power interface  350 , a memory  360 , a power management module  370 , and a battery  380 . 
     The processor  310  may execute, e.g., software to control at least one other component (e.g., a hardware or software component) of the first external electronic device  301  connected with the processor  310  and may process or compute various data. According to an embodiment, as at least part of the data processing or computation, the processor  310  may load a command or data received from another component (e.g., the sensor module  330  or communication module  320 ) onto a volatile memory  360 , process the command or the data stored in the volatile memory, and store resulting data in a non-volatile memory. 
     The communication module  320  may include a wireless communication module (e.g., a cellular communication module, a wireless-fidelity (Wi-Fi) communication module, a Bluetooth communication module, a near-field communication (NFC) communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). A corresponding communication module among these communication modules may communicate with at least one of an external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ) (e.g., a portable terminal), or electronic devices  201  and  202  through a first network (e.g., the first network  198  of  FIG. 1 ) or a second network (e.g., the second network  199  of  FIG. 1 ). The communication module  320  may include one or more communication processors that are operable independently from the processor  310  and supports a direct (e.g., wired) communication or a wireless communication. 
     The antenna module  321  may transmit a signal or power to another electronic device (e.g., an external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ) or electronic devices  201  and  202 ) or receive a signal or power from the other electronic device. According to an embodiment, the antenna module  321  may include one antenna including a radiator formed of a conductor or conductive pattern formed on a substrate (e.g., a printed circuit board (PCB)). According to an embodiment, the antenna module  321  may include a plurality of antennas. In this case, at least one antenna appropriate for a communication scheme used in a communication network, such as the first network (e.g., the first network  198  of  FIG. 1 ) or the second network (e.g., the second network  199  of  FIG. 2 ), may be selected from the plurality of antennas by, e.g., the communication module  320 . The signal or the power may then be transmitted or received between the communication module  320  and another electronic device via the selected at least one antenna. According to an embodiment, other parts (e.g., radio frequency integrated circuit (RFIC)) than the radiator may be further formed as part of the antenna module  321 . 
     The antenna module  321  may include at least one of a coil, where current may be induced by a magnetic field, a resonator, where a resonance phenomenon is generated by a magnetic field having a specific resonant frequency, or a plurality of patch antennas for receiving electromagnetic waves, to wirelessly receive power from a power source  305  or an external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ). 
     The antenna module  321  may include at least one of a coil forming a change in magnetic field, a resonator for forming a magnetic field with a specific resonant frequency, or a plurality of patch antennas for transmitting electromagnetic waves so as to wirelessly transmit power to the electronic devices  201  and  202 . 
     The sensor module  330  may measure a physical quantity or detect an operational state of the first external electronic device  301 . The sensor module  330  may convert the measured or detected information into an electrical signal. The sensor module  330  may include, e.g., an acceleration sensor, a gyro sensor, a geomagnetic sensor, a magnetic sensor, a proximity sensor, a gesture sensor, a grip sensor, an optical sensor, or a biometric sensor. According to an embodiment, the sensor module  330  may detect whether one or more of the electronic devices  201  and  202  are positioned in the first external electronic device  301 . According to an embodiment, the sensor module  330  may detect when the cover of the first external electronic device  301  is in an open state and when the cover is in a closed state. According to an embodiment, the processor  310  may be electrically connected with the sensor module  330  and may receive a signal indicating the open state and the closed state of the cover from the sensor module  330 . When one or more of the electronic devices  201  and  202  are positioned in the first external electronic device  301  and the cover is changed from the closed state to the open state, the processor  310  may generate a signal to turn on communication modules (e.g., the communication module  210  of  FIG. 2 ) of the electronic devices  201  and  202  and, when one or more of the electronic devices  201  and  202  are positioned in the first external electronic device  301  and the cover is changed from the open state to the closed state, the processor  310  may generate a signal to turn off the communication modules (e.g., the communication module  210  of  FIG. 2 ) of the electronic devices  201  and  202 . According to an embodiment, if the cover of the sensor module  330  is in the open state, the processor  310  may be triggered to allow the electronic devices  201  and  202  and the external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ) to enter a pairing mode. 
     The at least one charging indicator  335  may indicate the charge level of the battery  380  and/or the batteries (e.g., the battery  270  of  FIG. 2 ) of the electronic devices  201  and  202 . Through the charging indicator  335  on the surface of the first external electronic device  301 , the user may identify the amount of charge of the battery  380  of the first external electronic device  301  or the amount of charge of the batteries (e.g., the battery  270  of  FIG. 2 ) of the electronic devices  201  and  202 . The charging indicator  335  may be implemented as a display or may be implemented as an LED. 
     The input device  340  may be configured to generate various input signals required to operate the first external electronic device  301 . The input device  340  may include a touch pad, a touch panel, or a button. The touch pad may recognize touch inputs in at least one of capacitive, resistive, infrared, or ultrasonic methods. If a capacitive touch pad is provided, physical contact or proximity recognition may be possible. The touch pad may further include a tactile layer. The touch pad including the tactile layer may provide a tactile response to the user. The button may include, e.g., a physical button or an optical key. 
     The electronic device interface  345  may support one or more specified protocols to be used for the first external electronic device  301  to be connected with the electronic devices  201  and  202  directly or wirelessly. According to an embodiment, the electronic device interface  345  may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface, or an audio interface. According to an embodiment, the interface  345  may include connecting terminals for forming physical connections with the electronic devices  201  and  202 . According to an embodiment, the processor  310  may identify whether a physical connection is formed between the first external electronic device  301  and the electronic devices  201  and  202  through the electronic device interface  345 . According to an embodiment, if the processor  310  identifies a physical contact between the first external electronic device  301  and the electronic devices  201  and  202  through the electronic device interface  345 , the processor  310  may generate a charging signal that initiates charging of the electronic devices  201  and  202 . According to an embodiment, the processor  310  may identify, through the electronic device interface  345 , that either or both of the electronic devices  201  and  202  have been removed from the first external electronic device  301 , and the processor  310  may generate a removal signal for stopping charging of the removed electronic device  201  and/or  202 . 
     The power interface  350  may support one or more specified protocols to be used for the first external electronic device  301  to be connected with the power source  305  or the external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ) directly or wirelessly. The power interface  350  according to an embodiment may include some of a USB connector, a lightening connector, or a receptacle connector for another connector capable of providing power to the first external electronic device  301 . The power interface  350  according to an embodiment may adopt a structure including an antenna module  321  to wirelessly receive power from the power source  305  or an external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ). 
     The memory  360  may store various data used by at least one component (e.g., the processor  310  or a sensor module  330 ) of the first external electronic device  301 . The various data may include, for example, software and input data or output data for a command related thereto. The memory  360  may include a volatile memory or a non-volatile memory. 
     The memory  360  may store setting information related to a Bluetooth communication connection. The setting information may include at least one of first Bluetooth address information, second Bluetooth address information, or identification information for the first external electronic device  301 . According to an embodiment, the first Bluetooth address information or the second Bluetooth address information may include a Bluetooth device address (e.g., BD_ADDR) or LE address information generated based on the Bluetooth device address. According to an embodiment, the first Bluetooth address information or the second Bluetooth address information may further include device type information indicating one of a right earbud or a left earbud. According to an embodiment, the first Bluetooth address information or the second Bluetooth address information may further include device type information indicating one of a master device or a slave device. According to an embodiment, the first Bluetooth address information and the second Bluetooth address information may include different Bluetooth device addresses and device type information. According to an embodiment, the setting information regarding the Bluetooth communication connection may further include identification information for the first external electronic device  301 . According to an embodiment, the identification information for the first external electronic device  301  may include communication address information (e.g., MAC address or Bluetooth address) of the first external electronic device  301  or may include unique identification information, such as a serial number, set by the manufacturer of the first external electronic device  301 . The identification information for the first external electronic device  301  is not limited to the above example and may include information in various formats for identifying the first external electronic device  301 . 
     The memory  360  may store information regarding use of at least one of an NFC tag, a radio frequency identification (RFID) tag, a magnetic secure transmission (MST) device, a quick response (QR) code, or a bar code. According to certain embodiments, at least one of the NFC tag, the RFID tag, the MST device, the QR code, or the barcode may be included in the first external electronic device  301  or may be included in a component of the first external electronic device  301  illustrated in  FIG. 3  or may be implemented as a separate component in the first external electronic device  301 . At least one of the NFC tag, the RFID tag, the MST device, the QR code, or the barcode may store at least one of first Bluetooth address information, second Bluetooth address information, or identification information for the first external electronic device  301 . 
     The power management module  370  may manage power supplied to the first external electronic device  301 . According to one embodiment, the power management module  370  may be implemented as at least part of, for example, a PMIC. According to an embodiment, the power management module  370  may include a battery charging module. According to an embodiment, the power management module  370  may wirelessly or wiredly receive power from the power source  305  or an external electronic device (e.g., the second external electronic device  205  of  FIG. 2 ) under the control of the processor  310  and charge the battery  380 . According to an embodiment, the power management module  370  may wirelessly or wiredly provide the power of the battery to the electronic devices  201  and  202  through the electronic device interface  345  or the antenna module  321  under the control of the processor  310 . 
     The battery  380  may supply power to at least one component of the first external electronic device  301 . According to an embodiment, the battery  380  may include, for example, a primary cell which is not rechargeable, a secondary cell which is rechargeable, or a fuel cell. 
     The first electronic device  201  may identify at least one of the first Bluetooth address information, the second Bluetooth address information, or the identification information for the first external electronic device  301  stored in at least one of the memory  360 , the NFC tag, the RFID tag, the MST device, the QR code, or the barcode from the first external electronic device  301  through a communication module (e.g., the communication module  210  of  FIG. 2 ) or a sensor module (e.g., the sensor module  230  of  FIG. 2 ). 
     The first external electronic device  301  may further include various modules depending on the form in which it is provided. There are many variations according to the convergence trend of digital devices, so it is not possible to list them all, but components equivalent to the above-mentioned components may be further included in the first external electronic device  301 . Further, it is apparent that in the first external electronic device  301  according to an embodiment, specific components may be excluded from the above components or replaced with other components according to the form in which it is provided. This will be easily understood by those of ordinary skill in the art. 
       FIG. 4  is a view illustrating a first electronic device  201 , a second electronic device  202 , and/or an external electronic device  401  (e.g., the second external electronic device  205 ) in a wireless communication environment according to certain embodiments. 
     Either the first electronic device  201  forms a first communication connection  403 , with the external electronic device  401 , or the second electronic device  202  forms a second communication connection with the external electronic device  401 . The one of the first and second electronic device  201  and  202  that form the respective communication connection can be deemed the master device, while the other can be deemed the slave device. Additionally, the first electronic device  201  and the second electronic device  202  form a third communication connection  407  with each other. 
     Both the first electronic device  201  and the second electronic device  202  receive a voice signal output from their respective microphones. As noted above, the first electronic device  201  and the second electronic device  202  can determine noise information by comparing the voice signal output from the air conduction microphone with the voice signal output from the bone conduction microphone and/or acceleration sensor. The slave device provides the noise information to the master device. The master device compares the noise information from the slave device with the noise information at the master device. Where the master device determines that the slave device has less noise or a higher signal to noise ratio, the master device can transmit control signals on the third communication connection  407  to initiate change of roles where the master device becomes the slave device and vice versa. The master device, which was previously the slave device establishes a communication connection with the external electronic device  401 , while the slave device which was previously the master device releases a communication connection with the external electronic device  401 . 
       FIGS. 4-6  describe how the first electronic device  201  begins as the master device and maintains a first communication connection  403 . When the first electronic device  201  determines that the second electronic device  202  has less noise, the second electronic device  202  becomes the master device. The first electronic device  201  releases the first communication connection  403  and the second electronic device  202  establishes the second communication connection  405 . 
     The first electronic device  201  and/or the second electronic device  202  may be communicatively connected with the external electronic device  401 . For example, a communication connection (or a communication link) (e.g., the first communication connection  403  and/or the second communication connection  405 ) between the first electronic device  201  and/or the second electronic device  202  and the external electronic device  401  may be formed based on Bluetooth communication (e.g., Bluetooth low energy (BLE) communication and/or Bluetooth legacy communication). The above-described communication connection (or communication link) (e.g., the first communication connection  403  and/or the second communication connection  405 ) may be formed based on various communication schemes (e.g., Wi-Fi communication) other than Bluetooth communication and is not limited to the above-mentioned example. 
     The first electronic device  201  and the second electronic device  202  may be communicatively connected. For example, the communication connection (e.g., the third communication connection  407 ) between the first electronic device  201  and the second electronic device  202  may be formed based on Bluetooth communication (e.g., BLE communication). 
     According to certain embodiments, either the first electronic device  201  or the second electronic device  202  may be communicatively connected with the external electronic device  401 . For example, either the first electronic device  201  or the second electronic device  202  may be set as the master device, and the other may be set as a slave device. The master device may establish a communication connection with the external electronic device  401  to transmit and/or receive data to/from the external electronic device  401 . The slave device may transmit and/or receive data to/from the external electronic device  401  through the master device. More specifically, the slave device may receive at least a portion of data transmitted by the external electronic device  401  or data related thereto from the master device through the third communication connection  407 . The slave device may transmit data to be transmitted to the external electronic device  401  to the master device through the third communication connection  407 . At least a portion of the transmitted data or data related thereto may be transmitted to the external electronic device  401  by the master device. As another example, the slave device may obtain, from the master device, connection information for the communication connection formed between the master device and the external electronic device  401  (e.g., at least one of address information for the electronic device, clock information, channel information, service discovery protocol (SDP) result information, supported features, manufacture data, or key information (e.g., link key)). The slave device may obtain at least a portion of data transmitted by the external electronic device  401  and received by the master device based on the obtained connection information. 
     As described above, either the first electronic device  201  or the second electronic device  202  may be set as the master device, and the other may be set as a slave device. The master device may directly transmit and/or receive data through a communication connection to/from the external electronic device  401 . The slave device may receive data from the master device through a communication connection (e.g., the third communication connection  407 ) with the master device without forming a direct communication connection with the external electronic device  401  or may obtain data transmitted and/or received through the communication connection formed between the master device and the external electronic device  401 . A third communication connection  407  may be formed between the master device and the slave device, and data may be transmitted and/or received therebetween through the third communication connection  407 . 
     According to an embodiment, both the first electronic device  201  and the second electronic device  202  may be communicatively connected with the external electronic device  401 . For example, both the first communication connection  403  and the second communication connection  405  of  FIG. 4  may be formed. Data transmission and/or reception between the first electronic device  201  and the external electronic device  401  may be performed through the first communication connection  403 , and data transmission and/or reception between the second electronic device  202  and the external electronic device  401  may be performed through the second communication connection  405 . The communication connection (e.g., the third communication connection  407 ) between the first electronic device  201  and the second electronic device  202  may be omitted. 
     The first electronic device  201  and the second electronic device  202  each may include at least one microphone (e.g., the microphone  242  of  FIG. 2 ). The first electronic device  201  and the second electronic device  202  may detect (e.g., sense) an external voice using at least one microphone included therein. According to certain embodiments, since the external voices detected by the first electronic device  201  and the second electronic device  202  are detected every same time, they may be voices corresponding to (e.g., synchronized with) each other. The detected external voice may include the user&#39;s voice according to the user&#39;s utterance and/or noise from the ambient environment. 
     The first electronic device  201  and the second electronic device  202  obtain at least one voice signal output from their respective at least one microphone to obtain information for the noise from the ambient environment (hereinafter, noise information). For example, the first electronic device  201  and the second electronic device  202  may obtain noise information based on the voice signal output from an air conduction microphone and the voice signal output from a voice pickup unit (VPU) (e.g., a bone conduction microphone and/or an acceleration sensor). The operations for the first electronic device  201  and the second electronic device  202  to obtain noise information may be performed in synchronization with each other. For example, the operation in which each of the first electronic device  201  and the second electronic device  202  obtains noise information may be performed from the time when both the first electronic device  201  and the second electronic device  202  are removed from the first external electronic device (e.g., the first external electronic device  204  of  FIG. 2 ) or when both are plugged into the user&#39;s body (e.g., ears). When the first electronic device  201  and the second electronic device  202  each are removed from the first external electronic device  204  or worn on the user&#39;s body (e.g., ears), it may transmit an indication to the counterpart device to inform the counterpart device that it has been removed from the first external electronic device  204  or that it has been worn on the user&#39;s body (e.g., ear). The operation for each of the first electronic device  201  and the second electronic device  202  to obtain noise information may be performed every preset period (e.g., every same preset period). For example, the operation in which each of the first electronic device  201  and the second electronic device  202  obtains noise information may be performed, every preset period, from the time when both the first electronic device  201  and the second electronic device  202  are removed from the first external electronic device (e.g., the first external electronic device  204  of  FIG. 2 ) or when both are plugged into the user&#39;s body (e.g., ears). The noise information may include characteristics of ambient noise (e.g., noise level and/or noise type). For example, the noise type may be identified based on a variation in noise level. For example, the noise information may include average characteristics (e.g., long-term characteristics) of ambient noise that are measured for a preset time period (e.g., measured every preset period). As another example, the noise information may include instant characteristics (e.g., short-term characteristics) of ambient noise measured in real time. The noise information may include at least one of the presence or absence of directional noise (e.g., wind) detected from each of the first electronic device  201  and the second electronic device  202 , the magnitude of directional noise detected from each device, the level (e.g., magnitude) of noise detected from each device, or the signal-to-noise ratio (SNR) of the voice signal detected (or obtained) from each device, as identified from the characteristics of ambient noise (e.g., noise level and/or noise type). 
     The first electronic device  201  and the second electronic device  202  may obtain information for the ambient noise-reduced voice from at least one obtained voice signal based on their respective noise information. For example, the ambient noise-reduced voice may be a voice in which ambient noise has been reduced (or removed) from the external voice detected by at least one microphone. The user&#39;s voice according to the user&#39;s utterance may be detected more accurately. According to an embodiment, the first electronic device  201  and the second electronic device  202  perform signal processing (e.g., voice activity detection (VAD)) on at least one voice signal output from their respective at least one microphone, obtaining information for the ambient noise-reduced voice. 
     The first electronic device  201  or the second electronic device  202  may transmit its obtained noise information to the counterpart device. For example, of the first electronic device  201  and the second electronic device  202 , the electronic device set as the slave device may transmit its obtained noise information to the electronic device set as the master device through the third communication connection  407 . The master device may compare the noise information received from the slave device with its obtained noise information and set (e.g., change) the electronic device set as the slave device to the master device or maintain as the slave device, which is described in more detail in connection with the drawings. 
     The first electronic device  201  or the second electronic device  202  may transmit information for the voice signal to the external electronic device  401 . For example, information for the voice signal transmitted to the external electronic device  401  may include information for ambient noise-reduced voice. As another example, the information for the voice signal transmitted to the external electronic device  401  may include information for at least one voice signal obtained through at least one microphone by the first electronic device  201  or the second electronic device  202  (e.g., information for voice without reduction in ambient noise). The electronic device that transmits information for the voice signal to the external electronic device  401  may be the electronic device set as the master device. For example, of the first electronic device  201  and the second electronic device  202 , the electronic device set as the master device may transmit information for its obtained voice signal through a communication connection (e.g., the communication connection, corresponding to the master device, of the first communication connection  403  or the second communication connection  405 ) to the external electronic device  401 . For example, of the first electronic device  201  and the second electronic device  202 , the electronic device set as the slave device may not transmit information for its obtained voice signal to the external electronic device  401 . The electronic device set as the slave device may perform an operation for transmitting its obtained noise information to the master device without obtaining information for the voice signal. 
     In the following drawings, for convenience of description, the first electronic device  201  may be set as the master device, and the second electronic device  202  is set as the slave device unless otherwise specified. 
       FIG. 5A  is a flowchart  500   a  illustrating a method in which a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ) compares noise at the first electronic device  201  and noise at a second electronic device (e.g., the second electronic device  202  of  FIG. 2 ) and controls communication connection of the second electronic device  202 .  FIG. 5B  is a view illustrating a method in which a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ) compares noise at the first electronic device  201  and noise at a second electronic device (e.g., the second electronic device  202  of  FIG. 2 ) and controls communication connection of the second electronic device  202 . This is described below with reference to  FIGS. 5A and 5B  together. 
     The first electronic device  201  may establish a first communication connection  403  with an external electronic device (e.g., the external electronic device  401  of  FIG. 4 ) in operation  510   a . For example, each of the first electronic device  201  and the second electronic device  202  may identify whether it is worn on the user&#39;s ear using a sensor module (e.g., the sensor module  230  of  FIG. 2 ) (e.g., a proximity sensor) included therein. If it is identified that the first electronic device  201  is worn on the user&#39;s ear before the second electronic device  202  is worn, the first electronic device  201  may transmit information (e.g., an indication) indicating that the first electronic device  201  has been worn on the user&#39;s ear to the second electronic device  202  through to a third communication connection (e.g., the third communication connection  407  of  FIG. 4 ). Upon receiving the information (e.g., an indication) indicating that the first electronic device  201  is worn on the user&#39;s ear from the first electronic device  201  before it is identified that the second electronic device  202  is worn on the user&#39;s ear, the second electronic device  202  may identify that the second electronic device  202  is worn on the user&#39;s ear after the first electronic device  201  is worn. Upon identifying that the first electronic device  201  is worn on the user&#39;s ear before receiving the information (e.g., an indication) indicating that the second electronic device  202  is worn on the user&#39;s ear from the second electronic device  202 , the first electronic device  201  may identify that the first electronic device  201  is worn on the user&#39;s ear earlier than the second electronic device  202 . The first electronic device  201  first worn on the user&#39;s ear may be set as the master device, and the second electronic device  202  worn later on the user&#39;s ear may be set as the slave device. The first electronic device  201  set as the master device may establish a communication connection (e.g., the first communication connection  403 ) with the external electronic device  401  using a communication circuit (e.g., the communication module  210  of  FIG. 2 ) included in the first electronic device  201 . The second electronic device  202  set as the slave device may not form a communication connection (e.g., the second communication connection  405  of  FIG. 4 ) with the external electronic device  401 . 
     The first electronic device  201  may transmit information for a first voice signal to the external electronic device  401  through the first communication connection  403  in operation  530   a . For example, the first electronic device  201  may detect an external voice through at least one microphone (e.g., the microphone  242  of  FIG. 2 ) included in the first electronic device  201  and may obtain at least one voice signal (hereinafter, a first voice signal) output from at least one microphone (e.g., the microphone  242 ). The processor of the first electronic device  201  (e.g., the processor  290  of  FIG. 2 ) may obtain, from the obtained first voice signal, information for an ambient noise-reduced voice signal (hereinafter, information for the first voice signal). The processor  290  of the first electronic device  201  may transmit the information for the first voice signal to the external electronic device  401  through the first communication connection  403  using a communication circuit (e.g., the communication module  210 ). The transmitted information for the first voice signal may be transmitted, as call voice data, to another external electronic device (e.g., the electronic device  104 ) that, along with the external electronic device  401 , forms (e.g., is on the phone with the user of the external electronic device  401 ) a second network (e.g., the second network  199  of  FIG. 1 ). 
     The first electronic device  201  may receive second noise information for the second voice signal from the second electronic device  202  in operation  550   a . For example, like the first electronic device  201 , the second electronic device  202  may also detect an external voice through at least one microphone (e.g., the microphone  242 ) included in the second electronic device  202  and may obtain at least one voice signal (hereinafter, a second voice signal) output from at least one microphone (e.g., the microphone  242 ). The second voice signal may correspond to the first voice signal obtained by the first electronic device  201 . For example, the second voice signal may be a voice signal for the voice detected every same time as the voice of the first voice signal. The second electronic device  202  may obtain noise information for the second voice signal (hereinafter, second noise information) and may transmit the obtained second noise information to the first electronic device  201  through the third communication connection  407 . If it is identified based on the second noise information that the level of the ambient noise is greater than or equal to a threshold level (e.g., a second threshold level), the second electronic device  202  may transmit the second noise information to the first electronic device  201 . 
     In operation  570   a , the first electronic device  201  may transmit first control information to allow the second electronic device  202  to establish the second communication connection  405  with the external electronic device  401  based on the first noise information for the first voice signal and second noise information. For example, the first noise information may be noise information for the first voice signal obtained by the first electronic device  201 . For example, the first control information may include instructions (e.g., a command) commanding, or for allowing, the second electronic device  202  to establish the second communication connection  405  with the external electronic device  401 . For example, the first control information may include device information for the external electronic device  401 . The first electronic device  201  may identify an electronic device relatively less influenced by external noise by comparing the first noise information and the second noise information. If it is identified based on the first noise information that the level of the ambient noise is greater than or equal to a threshold level (e.g., the second threshold level), the first electronic device  201  may compare the first noise information and the second noise information. If it is identified that the voice detected from the second electronic device  202  is relatively less influenced by ambient noise as a result of comparison, the first electronic device  201  may perform at least one procedure to set the second electronic device  202  as the master device. For example, the first electronic device  201  may transmit the first control information to the second electronic device  202  through the third communication connection  407  to control the second electronic device  202  to form the second communication connection  405  (e.g., to allow the second electronic device  202  to initiate at least one procedure to form the second communication connection  405  with the external electronic device  401 ). As another example, the first electronic device  201  may transmit the first control information to the external electronic device  401  through the first communication connection  403  to control the external electronic device  401  to form the second communication connection  405  (e.g., to allow the external electronic device  401  to initiate at least one procedure to form the second communication connection  405  with the external electronic device  202 ). For example, the first electronic device  201  may release the formed first communication connection  403  based on transmitting the first control information (in other words, disconnect the first communication connection with the external electronic device  401 ). As another example, after transmitting the first control information, the first electronic device  201  may release the first communication connection  403  if receiving information indicating that the second communication connection  405  is established from the second electronic device  202  or the external electronic device  401 . As described above, it may be described as the communication connection between the first and second electronic devices  201  and  202  and the external electronic device  401  being switched  501  from the first communication connection  403  to the second communication connection  405 . 
     According to certain embodiments, as the second electronic device  202  is set (e.g., changed) to the master device while the information for the voice signal obtained through at least one microphone (e.g., the microphone  242 ) of the first electronic device  201  is transmitted to the external electronic device  401 , the information for the voice signal obtained through at least one microphone (e.g., the microphone  242 ) of the second electronic device  202  may be transmitted to the external electronic device  401 . 
     According to certain embodiments, if it is identified as a result of comparison that the voice detected by the first electronic device  201  is relatively less influenced by ambient noise, the first electronic device  201  may maintain the existing settings of the master device and the slave device. 
     The obtaining of a voice signal using at least one microphone of each of the first electronic device  201  and the second electronic device  202  may be performed regardless of the settings of the master device or the slave device. For example, the first electronic device  201  and the second electronic device  202  may receive the external voice through their at least one microphone regardless of whether the communication connection is established with the external electronic device  401 . The obtaining of the noise information for each of the first electronic device  201  and the second electronic device  202  may be performed irrespective of settings as the master device or the slave device. 
     As described above, the master device may compare the noise information for its obtained voice signal with the noise information for the voice signal obtained by the slave device and allows the user&#39;s voice, obtained through the electronic device relatively less influenced by external noise, to be transferred to the external electronic device, thereby enhancing call quality. 
       FIG. 6  is a flowchart  600  illustrating a method in which a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ) compares noise at the first electronic device  201  and noise at a second electronic device (e.g., the second electronic device  202  of  FIG. 2 ) and transmits first control information to control communication connection of the second electronic device  202 . It is assumed below that the first electronic device  201  may be set as the master device, and the second electronic device  202  is set as the slave device unless otherwise specified. 
     The first electronic device  201  may identify the first noise information and the second noise information in operation  610 . The first noise information may be noise information for the first voice signal obtained by the first electronic device  201 , and the second noise information may be noise information for the second voice signal obtained by the second electronic device  202 . For example, the first electronic device  201  may receive the second noise information from the second electronic device  202  and identify the second noise information. 
     According to certain embodiments, in operation  630 , the first electronic device  201  may identify whether the noise of the first voice signal exceeds the noise of the second voice signal. For example, the first electronic device  201  may identify characteristics of ambient noise included in each of the first noise information and the second noise information. The first electronic device  201  may identify whether the magnitude (e.g., level) of ambient noise included in the first noise information exceeds the magnitude (e.g., level) of ambient noise included in the second noise information. As another example, the first electronic device  201  may identify information identified from the characteristics of ambient noise included in each of the first noise information and the second noise information. The first electronic device  201  may identify whether the SNR of the first voice signal included in the first noise information is less than the SNR of the second voice signal included in the second noise information. As another example, if directional noise is detected from the first electronic device  201  (or the level of the directional noise is identified as greater than or equal to a threshold), and if directional noise is not detected from the second electronic device  202  (or the level of the directional noise is identified as less than the threshold) based on the first noise information and the second noise information, the first electronic device  201  may perform operation  650 . The first electronic device  201  may identify whether a difference between the noise of the first voice signal and the noise of the second voice signal is equal to or greater than a threshold level (e.g., the first threshold level) and, if it is identified that the difference between the noise of the first voice signal and the noise of the second voice signal is equal to or greater than the threshold level (e.g., the first threshold level), the first electronic device  201  may perform operation  650 . 
     According to certain embodiments, if it is identified that the noise of the first voice signal exceeds the noise of the second voice signal (e.g., if it is identified that the voice detected from the second electronic device  202  is relatively less influenced by ambient noise), the first electronic device  201  may transmit the first control information in operation  650 . For example, the first control information may include instructions to enable the second electronic device  202  to establish a communication connection (e.g., the second communication connection  405  of  FIG. 4 ) with the external electronic device  401 . According to certain embodiments, after transmitting the first control information, the first electronic device  201  may release the communication connection (e.g., the first communication connection  403  of  FIG. 4 ) with the external electronic device  401 . 
     According to certain embodiments, if it is identified that the noise of the first voice signal does not exceed the noise of the second voice signal (e.g., if it is identified that the voice detected from the first electronic device  201  is relatively less influenced by ambient noise), the first electronic device  201  may not transmit the first control information. Accordingly, the settings of the master device and the slave device may be maintained. 
     It is noted that after the second electronic device  202  becomes the master device, a circumstance may occur that the noise at the first electronic device  201  is less. Accordingly,  FIG. 7-8B  describe how the second electronic device  202  starts as the master device and becomes the slave device, and the first electronic device  201  starts as the slave device and becomes the master device. 
       FIG. 7  is a flowchart  700  illustrating a method in which a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ) provides information for noise at the first electronic device  201  to the second electronic device (e.g., the second electronic device  202  of  FIG. 2 ) after the communication connection (e.g., the first communication connection  403  of  FIG. 4 ) with the external electronic device according to certain embodiments. 
     The first electronic device  201  may transmit first control information and may release the first communication connection  403  in operation  710 . The second electronic device  202  may form the second communication connection (e.g., the second communication connection  405  of  FIG. 2 ) with the external electronic device (e.g., the external electronic device  401  of  FIG. 4 ) based on the transmission of the first control information. The first electronic device  201  may be set as the slave device (e.g., changed (e.g., switched) from the master device to the slave device), and the second electronic device  202  may be set as the master device (e.g., changed (e.g., switched) from the slave device to the master device). 
     According to certain embodiments, in operation  730 , the first electronic device  201  may obtain a third voice signal while the first communication connection  403  is released. For example, while the first communication connection  403  is released, the first electronic device  201  may detect an external voice through at least one microphone (e.g., the microphone  242  of  FIG. 2 ) included in the first electronic device  201  and may obtain at least one voice signal (hereinafter, a third voice signal) output from at least one microphone (e.g., the microphone  242 ). 
     The first electronic device  201  may identify the third noise information for the third voice signal in operation  750 . For example, the third noise information may include average characteristics (e.g., long-term characteristics) of ambient noise measured for a preset time while the first communication connection  403  is released. As another example, the third noise information may include instant characteristics (e.g., short-term characteristics) of ambient noise measured in real time while the first communication connection  403  is released. The operation of identifying the third noise information by the first electronic device  201  may be performed every preset period (e.g., every same preset period). 
     The first electronic device  201  may transmit third noise information to the second electronic device  202  in operation  770 . For example, the first electronic device  201  may transmit the third noise information identified while the first communication connection  403  is released, through the third communication connection (e.g., the third communication connection  407  of  FIG. 4 ) to the second electronic device  202 . 
     As described above, even after the first electronic device  201 , which used to be the master device, is changed (e.g., switched) to the slave device, the first electronic device  201  may perform the operations of obtaining the voice signal and identifying the noise information and may transmit (e.g., report) noise information to the second electronic device  202 . 
       FIG. 8A  is a flowchart  800   a  illustrating a method in which a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ) reestablishes a communication connection (e.g., the first communication connection  403  of  FIG. 2 ) with an external electronic device (e.g., the external electronic device  401  of  FIG. 4 ) according to certain embodiments.  FIG. 8B  is a view illustrating a method in which the first electronic device  201  reestablishes a communication connection (e.g., the first communication connection  403 ) with the external electronic device  401  according to certain embodiments. This is described below with reference to  FIGS. 8A and 8B  together. 
     The first electronic device  201  may transmit first control information and may release the first communication connection  403  in operation  810 A. The second electronic device (e.g., the second electronic device  202  of  FIG. 2 ) may form the second communication connection (e.g., the second communication connection  405  of  FIG. 2 ) with the external electronic device  401  based on the transmission of the first control information. The first electronic device  201  may be set as the slave device (e.g., changed (e.g., switched) from the master device to the slave device), and the second electronic device  202  may be set as the master device (e.g., changed (e.g., switched) from the slave device to the master device). 
     The first electronic device  201  may transmit third noise information for the third voice signal to the second electronic device  202  in operation  830   a.    
     According to certain embodiments, in operation  850   a , the first electronic device  201  may receive second control information for forming the first communication connection  403  with the external electronic device  403  based on the third noise information and fourth noise information for a fourth voice signal corresponding to the third voice signal. For example, like the first electronic device  201 , the second electronic device  202  may obtain the fourth voice signal by detecting an external voice through at least one microphone (e.g., the microphone  242  of  FIG. 2 ) included in the second electronic device  202 . The fourth voice signal obtained by the second electronic device  202  may be the voice signal for the voice detected every same time as the voice of the third voice signal. The second electronic device  202  may obtain noise information for the fourth voice signal (hereinafter, fourth noise information) and may compare the third noise information received from the first electronic device  201  with the obtained fourth noise information. If it is identified that the voice detected from the first electronic device  201  is relatively less influenced by ambient noise as a result of comparison, the second electronic device  202  may perform at least one procedure to set (e.g., change) the first electronic device  201  as the master device. For example, the second electronic device  202  may transmit the second control information to the first electronic device  201  through the third communication connection  407  to control the first electronic device  201  to form (e.g., reestablish) the first communication connection  403  (e.g., to allow the first electronic device  201  to initiate at least one procedure to reestablish the released first communication connection  403  with the external electronic device  401 ). As another example, the second electronic device  202  may transmit the second control information to the external electronic device  401  through the second communication connection  405  to control the external electronic device  401  to form (e.g., reestablish) the first communication connection  403  (e.g., to allow the external electronic device  401  to initiate at least one procedure to reestablish the released first communication connection  403  with the first electronic device  201 ). For example, the second control information may include instructions (e.g., a command) for allowing the first electronic device  201  to establish the first communication connection  403  with the external electronic device  401 . For example, the second control information may include device information for the external electronic device  401 . According to certain embodiments, while the first electronic device  201  establishes the first communication connection  403 , the second communication connection  405  of the second electronic device  202  may be released. As described above, it may be described as the communication connection between the first and second electronic devices  201  and  202  and the external electronic device  401  being switched  801  from the second communication connection  405  to the first communication connection  403 . According to certain embodiments, as the first electronic device  201  is set (e.g., changed) to the master device while the information for the voice signal obtained through at least one microphone (e.g., the microphone  242 ) of the second electronic device  202  is transmitted to the external electronic device  401 , the information for the voice signal obtained through at least one microphone (e.g., the microphone  242 ) of the first electronic device  201  may be transmitted to the external electronic device  401 . 
     According to certain embodiments, if it is identified that the voice detected by the second electronic device  202  is relatively less influenced by ambient noise, the second electronic device  202  may maintain the existing settings of the master device and the slave device. 
     As described above, the first electronic device  201 , which used to be the master device, may transmit (e.g., report) noise information to the second electronic device  202  even after changed (e.g., switched) to the slave device and may be changed (e.g., switched) back to the master device based on the control of the second electronic device  202  that has been changed (e.g., switched) to the master device. Thus, as the master device to detect the user&#39;s voice to be transmitted to the external electronic device  401  is changed back to the first electronic device  201 , call quality may be enhanced. 
     In certain embodiments, the noise information can be compared over regular intervals, e.g., t 1 , t 2 , t 3 , t 4 , and t 5 . In  FIG. 9 , it can be seen the first electronic device  201  is the master device at t 1 . At time t 3 , second electronic device  202  is becomes the master device. At the next interval, t 4 , first electronic device  201  becomes the master device. 
       FIG. 9  is a view illustrating a method for maintaining or changing a setting of a master device according to comparison of noise at a first and second electronic device (e.g., the first and second electronic devices  201  and  202  of  FIG. 2 ), performed in each preset period, according to certain embodiments. 
     According to certain embodiments, at t 1 , the first electronic device  201  may be set as the master device. For example, if the first electronic device  201  is worn on the user&#39;s ear before the second electronic device  202  is worn, the first electronic device  201  may be set as the master device, and that the second electronic device  202  may be set as the slave device. According to certain embodiments, as the first electronic device  201  is set as the master device at t 1 , the first electronic device  201  may establish a communication connection (e.g., the first communication connection  403  of  FIG. 4 ) with the external electronic device  401  and may transmit and/or receive data to/from the external electronic device  401  through the established communication connection (e.g., the first communication connection  403 ). For example, the first electronic device  201  may transmit information for the user&#39;s voice (e.g., information for the voice signal) detected through at least one microphone (e.g., the microphone  242  of  FIG. 2 ) included in the first electronic device  201  to the external electronic device  401  and receive, from the external electronic device  401 , data (e.g., data for call voice received from another external electronic device (e.g., the electronic device  104  of  FIG. 1 ) forming the second network (e.g., the second network  199  of  FIG. 1 ) with the external electronic device  401 ). Information for the user&#39;s voice detected by the first electronic device  201  may be transmitted to the other external electronic device  401  (e.g., the electronic device  104 ) forming the second network  199  with the external electronic device  401 , and the data received from the external electronic device  401  may be output through a speaker (e.g., the speaker  241  of  FIG. 2 ) of the first electronic device  201 . 
     According to certain embodiments, at t 2 , noises at the first electronic device  201  and the second electronic device  202  may be compared. The time interval (e.g., period) between t 1  and t 2  may be previously set. According to certain embodiments, at t 2 , the first electronic device  201 , which is the master device, may receive noise information for the external voice detected by the second electronic device  202  after t 1  (or from t 1 ) from the second electronic device  202  and compare it with noise information for the external voice detected by the first electronic device  201  after t 1  (or from t 1 ). If it is identified as a result of comparison that the voice detected by the first electronic device  201  is relatively less influenced by ambient noise, the first electronic device  201  may maintain the settings of the master device and the slave device. According to certain embodiments, as it is determined to maintain the settings of the master device and slave device at t 2 , the first electronic device  201  may continuously transmit and/or receive data to/from the external electronic device  401 . 
     According to certain embodiments, at t 3 , noises at the first electronic device  201  and the second electronic device  202  may be compared. The time interval (e.g., period) between t 2  and t 3  may be identical to the time interval between t 1  and t 2 , and may be preset. According to certain embodiments, at t 3 , the first electronic device  201 , which is set as the master device, may receive noise information for the external voice detected by the second electronic device  202  after t 2  (or from t 2 ) from the second electronic device  202  and compare it with noise information for the external voice detected by the first electronic device  201  after t 2  (or from t 2 ). If it is identified as a result of comparison that the voice detected by the second electronic device  202  is relatively less influenced by ambient noise, the first electronic device  201  may change the settings of the master device and the slave device. According to certain embodiments, as the settings of the master device and slave device are changed at t 3 , the second electronic device  202  may transmit and/or receive data to/from the external electronic device  401 . 
     According to certain embodiments, at t 4 , noises at the first electronic device  201  and the second electronic device  202  may be compared. The time interval (e.g., period) between t 3  and t 4  may be identical to the time interval between t 1  and t 2  and the time interval between t 2  and t 3  and may be preset. According to certain embodiments, at t 4 , the second electronic device  202 , which is set as the master device, may receive noise information for the external voice detected by the second electronic device  202  after t 3  (or from t 3 ) from the first electronic device  201  and compare it with noise information for the external voice detected by the second electronic device  202  after t 3  (or from t 3 ). If it is identified as a result of comparison that the voice detected by the first electronic device  201  is relatively less influenced by ambient noise, the second electronic device  202  may change the settings of the master device and the slave device. According to certain embodiments, as the settings of the master device and slave device are changed at t 4 , the first electronic device  201  may transmit and/or receive data to/from the external electronic device  401 . 
     According to certain embodiments, at t 5 , noises at the first electronic device  201  and the second electronic device  202  may be compared. The time interval (e.g., period) between t 4  and t 5  may be the same as the above-described time intervals. According to certain embodiments, even after t 5 , the electronic device set as the master device may receive noise information from the counterpart device (e.g., the slave device) every same time interval (e.g., period) and compare it with noise information for its detected external voice, maintaining or changing the settings of the master device and slave device. 
       FIG. 10  is a flowchart  1000  illustrating a method for operating a pair of earbuds (e.g., the first and second electronic devices  201  and  202  of  FIG. 2 ) according to certain embodiments. 
     It is assumed below that the first electronic device  201  is the left earbud and the second electronic device  202  is the right earbud. 
     In operation  1010 , an earbud to be used as a master device, of the left earbud or the right earbud, may be determined. For example, of the left earbud or the right earbud, the earbud first worn on the user&#39;s body (e.g., ear) may be determined as the earbud to be used as the master device. Of the left earbud or the right earbud, the earbud worn later on the user&#39;s body (e.g., ear) may be determined as the earbud to be used as the slave device. According to certain embodiments, a communication connection (e.g., the third communication connection  407  of  FIG. 4 ) may be formed between the left earbud and the right earbud, and a communication connection (e.g., the communication connection, corresponding to the master device, of the first communication connection  403  or the second communication connection  405  of  FIG. 4 ) may be formed between the earbud determined as the master device and the external electronic device (e.g., the external electronic device  401  of  FIG. 4 ). 
     In operation  1020 , noise information may be calculated from each earbud. For example, external voices may be detected through the microphone of the left earbud (e.g., the microphone  242  of  FIG. 2 ) and the microphone of the right earbud (e.g., the microphone  242 ), and noise information for the external voice detected by each earbud may be calculated (e.g., identified). 
     In operation  1030 , the slave device may transfer noise information to the master device. For example, the earbud determined as the slave device may transmit noise information, it calculated (e.g., identified), to the master device through the communication connection (e.g., the third communication connection  407 ) formed with the master device. For example, an operation in which the slave device transfers noise information may be performed every preset period. 
     In operation  1040 , the master device may identify noise information from both the earbuds. For example, the master device may identify each of the noise information transferred from the slave device and the noise information it calculated (e.g., identified). 
     In operation  1050 , the master device may identify whether the noise at the left earbud is greater than the noise at the right earbud. For example, the master device may compare the identified noise information to identify whether the influence of external noise on the voice detected by the left earbud is greater than the influence of the external noise on the voice detected by the right earbud. 
     If it is not identified that the noise at the left earbud is greater than the noise at the right earbud, in operation  1060 , the left earbud may be set as the master device. For example, if the left earbud is the earbud determined as the master device in operation  1010 , the settings of the master device and the slave device may be maintained. For example, if the left earbud is the earbud determined as the slave device in operation  1010 , the settings of the master device and the slave device may be changed according to the control of the master device (e.g., the right earbud). 
     In operation  1070 , the left earbud may transfer the voice obtained by the microphone (e.g., the microphone  242  of  FIG. 2 ) to the external electronic device  401 . The left earbud may receive data (e.g., call voice data) from the external electronic device  401  and output the call voice through a speaker (e.g., the speaker  241  of  FIG. 2 ) included in the left earbud. The right earbud may receive data (e.g., call voice data), received by the left earbud from the external electronic device  401 , from the left earbud or may obtain data (e.g., call voice data) based on connection information for the communication connection formed between the left earbud and the external electronic device  401  and output the call voice through a speaker (e.g., the speaker  241 ) included in the right earbud. Even thereafter, the right earbud set (or changed) as the slave may obtain an external voice through a microphone (e.g., the microphone  242 ), identify noise information for the external voice, and transfer it to the left earbud. 
     According to certain embodiments, if it is identified that the noise at the left earbud is greater than the noise at the right earbud, in operation  1080 , the right earbud may be set as the master device. For example, if the right earbud is the earbud determined as the master device in operation  1010 , the settings of the master device and the slave device may be maintained. For example, if the right earbud is the earbud determined as the slave device in operation  1010 , the settings of the master device and the slave device may be changed according to the control of the master device (e.g., the left earbud). 
     In operation  1090 , the right earbud may transfer the voice obtained by the microphone (e.g., the microphone  242 ) to the external electronic device  401 . The left earbud may receive data (e.g., call voice data) from the external electronic device  401  and output the call voice through a speaker (e.g., the speaker  241 ) included in the right earbud. The left earbud may receive data (e.g., call voice data), received by the right earbud from the external electronic device  401 , from the right earbud or may obtain data (e.g., call voice data) based on connection information for the communication connection formed between the right earbud and the external electronic device  401  and output the call voice through a speaker (e.g., the speaker  241 ) included in the left earbud. Even thereafter, the left earbud set (or changed) as the slave may obtain an external voice through a microphone (e.g., the microphone  242 ), identify noise information for the external voice, and transfer it to the right earbud. 
     The above-described operations of the left earbud and right earbud (e.g., the first and second electronic devices  201  and  202 ) may be described below as an example. 
     For example, it may be hypothesized that the user rides and drives a vehicle while wearing the left earbud and the right earbud on her ears. If the user puts the left earbud on the ear before the right earbud, the left earbud may be set as the master device, and the right earbud may be set as the slave device. If the user is on a call with another person, the user&#39;s voice detected through the microphone of the left earbud, which is the master device, may be transferred to the device of the other person on the call. It may be assumed that the user opens the left window while sitting on the left seat of the vehicle. If wind enters the vehicle through the left window, wind noise may have a more influence on the left earbud than the right earbud. The master device, the left earbud, may identify that the noise to itself is greater than the noise to the right earbud, and the right earbud may be set to the master device, and the left earbud may be changed to the slave device. Thereafter, the user&#39;s voice detected through the microphone of the right earbud set (e.g., changed) as the master device may be transferred to the device of the other party on the call. It may be assumed that the user opens the right window while sitting on the left seat of the vehicle. If wind enters the vehicle through the right window, wind noise may have a more influence on the right earbud than the left earbud. The master device, the left earbud, may identify that the noise to itself is smaller than the noise to the right earbud, and the settings of the master device and slave device may be maintained. 
     As described above, the ear-wearable device composed of a pair of earbuds allows the user&#39;s voice detected through the earbuds with less noise influence (e.g., noise) to be transferred to the other party on the call, enhancing call quality. 
     In certain embodiments, the master and slave device can be changed in response to user input. When the left earbud  1109  is the master electronic device and detects that the right earbud  1111  has less noise, the left earbud  1109  can cause electronic device  401  to display a graphical user interface  1103  indicating the same. The graphical user interface  1103  can ask the user whether they would like to switch to using the microphone with the right earbud  1111 . Responsive to selection of the YES button  1105 , the left earbud  1109  and right earbud  1111  swap roles. 
       FIG. 11  illustrates an example of a screen that may be displayed on a display  1101  (e.g., the display module  160  of  FIG. 1 ) of the external electronic device  401  according to certain embodiments. 
     The external electronic device  401  may receive a message indicating that the settings of the master device and the slave device may be changed from a first electronic device (e.g., the first electronic device  201 ) and/or a second electronic device (e.g., the second electronic device  202  of  FIG. 2 ). For example, the external electronic device  401  may receive a message indicating that the master device may be changed to the slave device from the master device of the first electronic device  201  and the second electronic device  202 . 
     According to certain embodiments, if the message indicating that the settings of the master device and the slave device are changed is received, the external electronic device  401  may display a notification message  1103  illustrated in  FIG. 11  on the display  1101 . The notification message  1103  may include information (e.g., “The performance of the microphone currently in use has reduced”) indicating that the noise of the external voice detected by the master device exceeds a certain level or the noise of the external voice detected by the master device is relatively larger than the noise for the external voice detected by the slave device. The notification message  1103  may include information (e.g., “Do you want to continue the call on a new microphone?”) indicating that the settings of the master device and the slave device may be changed. The notification message  1103  may include information for the earbud currently set as the master device (e.g., “Microphone currently in use: L”) and/or information for the earbud to be set (or changed) as the master device (e.g., “New microphone: R”). 
     According to certain embodiments, if an input (e.g., a touch input) for selecting a first option  1105  is detected through the display  1101  (e.g., a touchscreen), the external electronic device  401  may transmit an approval message to the master device (e.g., the earbud corresponding to L). The master device (e.g., the earbud corresponding to L) may change the settings of the master device and the slave device if the approval message is received. For example, the master device (e.g., the earbud corresponding to L) may transmit control information for establishing a communication connection between the external electronic device  401  and the slave device to the slave device (e.g., the earbud corresponding to R) or the external electronic device  401 . The master device (e.g., the earbud corresponding to L) may be changed to the slave device (e.g., the communication connection between the earbud corresponding to L and the external electronic device  401  is released), and the slave device (e.g., the earbud corresponding to R) may be changed to the master device (e.g., a communication connection between the earbud corresponding to R and the external electronic device  401  is formed). 
     According to certain embodiments, if an input (e.g., a touch input) for selecting a second option  1107  is detected through the display  1101  (e.g., a touchscreen), the external electronic device  401  may transmit no approval message or a rejection message to the master device (e.g., the earbud corresponding to L). The master device (e.g., the earbud corresponding to L) may maintain the settings of the master device and the slave device if an approval message is not received or a rejection message is received within a preset time. 
     According to certain embodiments, information (e.g., text and/or images) indicating the current settings of the master device and the slave device may be displayed on the display  1101 . For example, a first object  1109  representing the left earbud and a second object  1111  representing the right earbud may be displayed. According to the current settings of the master device and the slave device, the first object  1109  and the second object  1111  may be displayed to be visually distinguished from each other. For example, if the left earbud is set as the master device, a visual effect (e.g., a shadow effect) may be displayed on the image of the first object  1109 , or text (e.g., “L”) of the first object  1109  may be displayed in bold. According to certain embodiments, if the settings of the master device and the slave device are changed, the display of the first object  1109  and/or the second object  1111  may be changed to correspond to the changed settings. For example, if the right earbud is changed to the master device, a visual effect (e.g., a shadow effect) may be displayed on the image of the second object  1111 , or the text (e.g., “R”) of the second object  1111  may be displayed in bold. 
     According to certain embodiments, a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ) may comprise at least one microphone (e.g., the microphone  242  of  FIG. 2 ), a communication circuit (e.g., the communication module  210  of  FIG. 2 ), and at least one processor (e.g., the processor  290  of  FIG. 2 ). The at least one processor may be configured to establish a first communication connection with an external electronic device using the communication circuit, transmit, through the first communication connection, to the external electronic device, using the communication circuit, information for a first voice signal obtained using the at least one microphone, receive second noise information for a second voice signal from a second electronic device (e.g., the second electronic device  202  of  FIG. 2 ), by the communication circuit, wherein the second voice signal corresponding to the first voice signal was obtained by the second electronic device while the information for the first voice signal was transmitted to the external electronic device, and transmit, based on first noise information for the first voice signal and the received second noise information, first control information for allowing the second electronic device to establish a second communication connection with the external electronic device, using the communication circuit. 
     According to certain embodiments, the at least one processor may be further configured to disconnect the first communication connection established with the external electronic device, responsive to transmitting of the first control information. 
     According to certain embodiments, the at least one processor may be further configured to obtain a third voice signal using the at least one microphone, while the first communication connection is disconnected, identify third noise information for the obtained third voice signal, and transmit the identified third noise information to the second electronic device using the communication circuit. 
     According to certain embodiments, the at least one processor may be further configured to after disconnecting the first communication connection, receive second control information for reestablishing the first communication connection with the external electronic device using the communication circuit, and reestablish the first communication connection based on the receiving of the second control information. 
     According to certain embodiments, the at least one processor may be configured to identify a difference between a noise of the first voice signal and a noise of the second voice signal, based on the first noise information and the received second noise information. 
     According to certain embodiments, the at least one processor may be configured to identify whether the difference between the noise of the first voice signal and the noise of the second voice signal is equal to or greater than a first threshold, and transmit the first control information, based on identifying that the difference between the noise of the first voice signal and the noise of the second voice signal is equal to or greater than the first threshold. 
     According to certain embodiments, the at least one processor may be further configured to identify the first noise information, identify whether a noise of the first voice signal is equal to or greater than a second threshold, and compare the first noise information and the received second noise information, based on identifying that the noise of the first voice signal is equal to or greater than the second threshold. 
     According to certain embodiments, the at least one processor may be further configured to identify at least one of whether a directional noise exists, a magnitude of the directional noise, a level of noise detected from the first electronic device and the second electronic device, or a signal-to-noise ratio (SNR) of a voice signal detected from the first electronic device and the second electronic device, based on the first noise information and the second noise information. 
     According to certain embodiments, the first noise information may include an average value of noise information of a voice signal obtained during a predetermined period using the at least one microphone. The average value of the noise information may be identified every preset period. 
     According to certain embodiments, the first electronic device may be set as a master device while the first communication connection is established, and the second electronic device may be set as the master device while the second communication connection is established. An electronic device set as the master device between the first electronic device and the second electronic device may be configured to compare noise information and transmit information for a voice signal to the external electronic device. 
     According to certain embodiments, a method for controlling a first electronic device may comprise establishing a first communication connection with an external electronic device, using a communication circuit of the first electronic device, transmitting through the established first communication connection, to the external electronic device, using the communication circuit, information for a first voice signal obtained using at least one microphone of the first electronic device, receiving second noise information for a second voice signal from a second electronic device, using the communication circuit, wherein a second voice signal corresponding to the first voice signal is obtained by the second electronic device while the information for the first voice signal is transmitted to the external electronic device; and transmitting, based on first noise information for the first voice signal and the received second noise information, first control information for allowing the second electronic device to establish a second communication connection with the external electronic device, using the communication circuit. 
     The method may further comprise disconnecting the first communication connection established with the external electronic device, responsive to the transmitting of the first control information. 
     According to certain embodiments, the method may further comprise obtaining a third voice signal, using the at least one microphone, while the first communication connection is disconnected, identifying third noise information for the obtained third voice signal, and transmitting the identified third noise information to the second electronic device using the communication circuit. 
     According to certain embodiments, the method may further comprise, after disconnecting the first communication connection, receiving second control information for reestablishing the first communication connection with the external electronic device using the communication circuit, and reestablishing the first communication connection, based on the receiving of the second control information. 
     According to certain embodiments, transmitting the first control information, based on the first noise information and the received second noise information, may include identifying a difference between a noise of the first voice signal and a noise of the second voice signal, based on the first noise information and the received second noise information. 
     According to certain embodiments, the method for controlling the first electronic device may further comprise identifying the first noise information, identifying whether noise of the first voice signal is a second threshold or more, and comparing the first noise information and the received second noise information based on identifying that the noise of the first voice signal is the second threshold or more. 
     According to certain embodiments, the method may further comprise identifying whether the difference between the noise of the first voice signal and the noise of the second voice signal is equal to or greater than a first threshold, and wherein the specified condition is whether the difference between the noise of the first voice signal and the noise of the second voice signal is equal to or greater than the first threshold. 
     According to certain embodiments, the method may further comprise identifying the first noise information, identifying whether a noise of the first voice signal is equal to or greater than a second threshold, and comparing the first noise information and the received second noise information, based on identifying that the noise of the first voice signal is equal to or greater than the second threshold. 
     According to certain embodiments, the method may further comprise identifying at least one of whether a directional noise exists, a magnitude of the directional noise, a level of noise detected from the first electronic device and the second electronic device, or a signal-to-noise ratio (SNR) of a voice signal detected from the first electronic device and the second electronic device, based on the first noise information and the second noise information. 
     According to certain embodiments, the first noise information includes an average value of noise information of a voice signal obtained during a predetermined period using the at least one microphone, and wherein the average value of the noise information is identified every preset period. 
     According to certain embodiments, a second electronic device (e.g., the second electronic device  202  of  FIG. 2 ) may comprise at least one microphone (e.g., the microphone  242  of  FIG. 2 ), a communication circuit (e.g., the communication module  210  of  FIG. 2 ), and at least one processor (e.g., the processor  290  of  FIG. 2 ). The at least one processor may be configured to obtain a second voice signal using the at least one microphone, the second voice signal being obtained while information for a first voice signal corresponding to the second voice signal, obtained by a first electronic device (e.g., the first electronic device  201  of  FIG. 2 ), is transmitted to an external electronic device, identify second noise information for the obtained second voice signal, transmit the identified second noise information to the first electronic device using the communication circuit, receive first control information for establishing a second communication connection with the second electronic device using the communication circuit based on the transmission of the second noise information, establish a second communication connection with the external electronic device using the communication circuit based on the reception of the first control information, and transmit information for a voice signal obtained using the at least one microphone to the external electronic device through the established second communication connection. 
     The at least one processor may be configured to receive, from the first electronic device, third noise information for a third voice signal obtained by the first electronic device while the second communication connection is established, using the communication circuit and transmit second control information for allowing the first electronic device to establish the first communication connection with the external electronic device using the communication circuit based on fourth noise information for the fourth voice signal corresponding to the third voice signal and the received third noise information. The fourth voice signal may be obtained using the at least one microphone. 
     The at least one processor may be configured to disconnect the second communication connection established with the external electronic device, based on the transmission of the second control information. 
     The at least one processor may be configured to obtain a fifth voice signal using the at least one microphone, while the second communication connection is disconnected, identify fifth noise information for the obtained fifth voice signal, and transmit the identified fifth noise information to the first electronic device using the communication circuit. 
     The electronic device according to certain embodiments may be one of various types of electronic devices. The electronic devices may include, for example, a portable communication device (e.g., a smart phone), a computer device, a portable multimedia device, a portable medical device, a camera, a wearable device, or a home appliance. According to an embodiment of the disclosure, the electronic devices are not limited to those described above. 
     It should be appreciated that certain embodiments of the present disclosure and the terms used therein are not intended to limit the technological features set forth herein to particular embodiments and include various changes, equivalents, or replacements for a corresponding embodiment. With regard to the description of the drawings, similar reference numerals may be used to refer to similar or related elements. It is to be understood that a singular form of a noun corresponding to an item may include one or more of the things, unless the relevant context clearly indicates otherwise. As used herein, each of such phrases as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B, or C,” “at least one of A, B, and C,” and “at least one of A, B, or C,” may include all possible combinations of the items enumerated together in a corresponding one of the phrases. As used herein, such terms as “1st” and “2nd,” or “first” and “second” may be used to simply distinguish a corresponding component from another, and does not limit the components in other aspect (e.g., importance or order). It is to be understood that if an element (e.g., a first element) is referred to, with or without the term “operatively” or “communicatively”, as “coupled with,” “coupled to,” “connected with,” or “connected to” another element (e.g., a second element), it means that the element may be coupled with the other element directly (e.g., wiredly), wirelessly, or via a third element. 
     As used herein, the term “module” may include a unit implemented in hardware, software, or firmware, and may interchangeably be used with other terms, for example, “logic,” “logic block,” “part,” or “circuitry”. A module may be a single integral component, or a minimum unit or part thereof, adapted to perform one or more functions. For example, according to an embodiment, the module may be implemented in a form of an application-specific integrated circuit (ASIC). 
     Certain embodiments as set forth herein may be implemented as software (e.g., the program  140 ) including one or more instructions that are stored in a storage medium (e.g., internal memory  136  or external memory  138 ) that is readable by a machine (e.g., the electronic device  101 ). For example, a processor (e.g., the processor  120 ) of the machine (e.g., the electronic device  101 ) may invoke at least one of the one or more instructions stored in the storage medium, and execute it, with or without using one or more other components under the control of the processor. This allows the machine to be operated to perform at least one function according to the at least one instruction invoked. The one or more instructions may include a code generated by a complier or a code executable by an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. Wherein, the term “non-transitory” simply means that the storage medium is a tangible device, and does not include a signal (e.g., an electromagnetic wave), but this term does not differentiate between where data is semi-permanently stored in the storage medium and where the data is temporarily stored in the storage medium. 
     According to an embodiment, a method according to certain embodiments of the disclosure may be included and provided in a computer program product. The computer program products may be traded as commodities between sellers and buyers. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read only memory (CD-ROM)), or be distributed (e.g., downloaded or uploaded) online via an application store (e.g., Play Store™), or between two user devices (e.g., smart phones) directly. If distributed online, at least part of the computer program product may be temporarily generated or at least temporarily stored in the machine-readable storage medium, such as memory of the manufacturer&#39;s server, a server of the application store, or a relay server. 
     According to certain embodiments, each component (e.g., a module or a program) of the above-described components may include a single entity or multiple entities. Some of the plurality of entities may be separately disposed in different components. According to certain embodiments, one or more of the above-described components may be omitted, or one or more other components may be added. Alternatively or additionally, a plurality of components (e.g., modules or programs) may be integrated into a single component. In such a case, The integrated component may still perform one or more functions of each of the plurality of components in the same or similar manner as they are performed by a corresponding one of the plurality of components before the integration. According to certain embodiments, operations performed by the module, the program, or another component may be carried out sequentially, in parallel, repeatedly, or heuristically, or one or more of the operations may be executed in a different order or omitted, or one or more other operations may be added.