Patent Publication Number: US-11031008-B2

Title: Terminal device and method for controlling thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is based on and claims priority under 35 U.S.C. § 119(a) of a Korean patent application number 10-2018-0163354, filed on Dec. 17, 2018, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Field 
     The disclosure relates to a terminal device and a controlling method thereof. More particularly, the disclosure relates to a terminal device for determining a device, from among a plurality of terminal devices, to acquire a sound wave generated by a user to recognize voice, and a controlling method thereof. 
     2. Description of Related Art 
     In recent years, artificial intelligence (AI) systems that implement human intelligence have been used in various fields. An AI system is a system that the machine learns, judges, and becomes smart, unlike the existing rule-based smart system. As the use of AI systems improves, a recognition rate and understanding or anticipation of a user&#39;s taste may be performed more accurately. As such, existing rule-based smart systems are gradually being replaced by deep learning-based AI systems. 
     AI technology is composed of machine learning (for example, deep learning) and elementary technologies which utilizes machine learning. 
     Machine learning is an algorithm technology that is capable of classifying or learning characteristics of input data without additional information or intervention. Element technology is a technology that simulates functions such as recognition and judgment of human brain using machine learning algorithms such as deep learning. Machine learning relies on numerous technical fields such as linguistic understanding, visual understanding, reasoning, prediction, knowledge representation, motion control, etc. 
     Various fields in which AI technology is applied include, for example, linguistic understanding, visual understanding, inference prediction, knowledge representation, and motion control. Linguistic understanding is a technology for recognizing, applying, and/or processing human language or characters and includes natural language processing, machine translation, dialogue system, question and answer, voice recognition or synthesis, and the like. Visual understanding is a technique for recognizing and processing objects as human vision, including object recognition, object tracking, image search, human recognition, scene understanding, spatial understanding, image enhancement, and the like. Inference prediction is a technique for judging and logically inferring and predicting information, including knowledge-based and probability-based inference, optimization prediction, preference-based planning, and recommendation. Knowledge representation is a technology for automating human experience information into knowledge data, including knowledge building (data generation or classification) and knowledge management (data utilization). Motion control is a technique for controlling the autonomous running of the vehicle and the motion of the robot, including motion control (navigation, collision, driving), operation control (behavior control), and the like. 
     Meanwhile, in recent years, various services using an AI agent (for example, Bixby™, Assistant™, Alexa™, etc.) for providing a response to a user&#39;s voice input have been provided. However, when there is a plurality of devices in which include an artificial intelligent agent provided within a small geographical area, there is confusion such that a plurality of devices receiving a user&#39;s voice provide responses. 
     The above information is presented as background information only to assist with an understanding of the disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the disclosure. 
     SUMMARY 
     Aspects of the disclosure are to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the disclosure is to provide an electronic device which determines a device, from among a plurality of terminal devices, to acquire a sound wave generated by a user to recognize voice, and a controlling method thereof, in consideration of at least one of performance information and voice reception quality information. 
     Another aspect of the disclosure is to provide a communication interface comprising communication circuitry, and a processor configured to receive performance information of one or more other terminal devices from each of the one or more other terminal devices through the communication interface, identify an edge device to perform voice recognition from among the terminal device and the one or more other terminal devices based on the performance information received from each of the one or more other terminal devices, based on the terminal device being identified as the edge device, receive information associated with reception quality from one or more other terminal devices which receive a sound wave including a triggering word from among the one or more other terminal devices which transmit the performance information, determine a terminal device to acquire the sound wave for voice recognition from based on the received information associated with the reception quality, from among the one or more other terminal devices which receive the sound wave, and transmit, to the determined terminal device, a command to transmit the sound wave acquired for voice recognition to an external voice recognition device. 
     Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments. 
     The performance information received from each of the one or more other terminal devices comprises a first score that is acquired based on performance of the one or more other terminal devices, and the information associated with reception quality that is received from the one or more other terminal devices which receive the sound wave may include a second score that represents reception quality associated with the sound wave received by the one or more terminal devices. 
     The processor may determine a terminal device having a highest second score value, from among the one or more other terminal devices which receive the sound wave, as a terminal device to acquire the sound wave for voice recognition. 
     In accordance with an aspect of the disclosure, a terminal device is provided. The terminal device may further include a microphone, and the processor acquires a second score of the terminal device based on at least a part of the sound wave based on the sound wave including the triggering word being received at the microphone, determine a terminal device having a highest second score, from among the terminal device and the one or more other terminal devices which receive the sound wave, as a terminal device to acquire the sound wave for voice recognition, and based on the terminal device being determined as a terminal device to acquire the sound wave, acquire a portion of the sound wave that is received after the triggering word and transmit the acquired portion of the sound wave to an external voice recognition device. 
     The information on the reception quality may be acquired based on at least one of a signal to noise ratio (SNR), a volume of the received sound wave, a change rate of the volume of the received sound wave, sound pressure, and distance from a source of the sound wave. 
     The performance information may be acquired based on at least one of a number of connected other terminal devices, a number of types of available communication networks, a connection method with a server, a power supply method, processing performance, memory performance, and a location movement status. 
     The processor may, based on a second score of the determined terminal device being less than a preset value, change a terminal device having a highest second score value, from among the one or more other terminal devices which receive the sound wave, as a terminal device to acquire the sound wave for voice recognition. 
     At least one of a first score and a second score received from each of the one or more other terminal devices may include information on at least one of the first score and the second score of a terminal device which is in communication with the one or more other terminal devices and which is not in communication with the terminal device. 
     In accordance with another aspect of the disclosure, a terminal device is provided. The terminal device may further include a memory including a voice recognition module, the processor may, based on the sound wave being received from the determined terminal device, perform voice recognition on the sound wave using the voice recognition module, and transmit the voice recognition result to an external server, and the external server may determine a terminal device to perform an operation to correspond to the voice recognition result from among the terminal device and the one or more other terminal devices based on the voice recognition result, and transmit an operation execution command corresponding to the voice recognition result to a terminal device to perform the operation. 
     In accordance with another aspect of the disclosure, a terminal device is provided. The terminal device may further include a microphone, and the processor may, based on the first score of the terminal device being less than the first score of the one or more other terminal devices, determine other terminal device having a highest first score, from among the one or more other terminal devices, as an edge device, based on the sound wave including the triggering word being received at the microphone, acquire information associated with reception quality based on at least a part of the sound wave, and transmit the acquired information on the reception quality to the determined edge device. 
     The processor may, based on the second score of the terminal device being less than a preset value, not transmit the second score to the determined edge device. 
     In accordance with an aspect of the disclosure, a method of controlling a terminal device is provided. The method includes receiving information on performance information of the one or more other terminal devices from each of the one or more other terminal devices, identifying an edge device to determine a terminal perform voice recognition from among the terminal device and the one or more other terminal devices based on the performance information received from each of the one or more other terminal devices, based on the terminal device being identified as the edge device, receiving information associated with reception quality from one or more other terminal devices which receive a sound wave including a triggering word from among the one or more other terminal devices which transmit the performance information, determining a terminal device to acquire the sound wave for voice recognition from based on the received information associated with the reception quality, from among the one or more other terminal devices which receive the sound wave, and transmitting, to the determined terminal device, a command to transmit the sound wave acquired for voice recognition to an external voice recognition device. 
     The performance information received from each of the one or more other terminal devices may include a first score that is acquired based on performance of the other terminal devices, and the information associated with reception quality that is received from the one or more other terminal devices which receive the wound wave may include a second score that represents reception quality associated with the sound wave received by the one or more other terminal devices. 
     The determining may include determining a terminal device having a highest second score value, from among the one or more other terminal devices which receive the sound wave, as a terminal device to acquire the sound wave for voice recognition. 
     The determining may include, based on the sound wave including the triggering word being received the microphone, acquiring a second score of the terminal device based on at least a part of the sound wave, determining a terminal device having a highest second score, from among the terminal device and the one or more other terminal devices which receive the sound wave, as a terminal device to acquire the sound wave for voice recognition, based on the terminal device being determined as a terminal device to acquire the sound wave, acquiring a portion of the sound wave that is received after the triggering word, and transmitting the acquired portion of the sound wave to an external voice recognition device. 
     The information on the voice reception quality may be acquired based on at least one of a SNR, a volume of the received sound wave, a change rate of the volume of the received sound wave, sound pressure, and distance from the source of the sound wave. 
     The performance information may be acquired based on at least one of a number of connected other terminal devices, a number of types of available communication networks, a connection method with a server, a power supply method, processing performance, memory performance, and location movement status. 
     In accordance with an aspect of the disclosure, a controlling method is provided. The method includes, based on a second score of the determined terminal device being less than a preset value, changing a terminal device having a highest second score value, from among the one or more other terminal devices which receive the sound wave, as a terminal device to acquire the sound wave for voice recognition. 
     At least one of a first score and a second score received from each of the one or more other terminal devices may include information on at least one of the first score and the second score of a terminal device which is in communication with the one or more other terminal devices and which is not in communication with the terminal device. 
     In accordance with an aspect of the disclosure, a controlling method is provided. the method includes, based on the sound wave being received from the determined terminal device, performing voice recognition on the received sound wave using the voice recognition module stored in a memory, and transmitting the voice recognition result to an external server, and the external server may determine a terminal device to perform an operation to correspond to the voice recognition result from among the terminal device and the one or more other terminal devices based on the voice recognition result, and transmit an operation execution command corresponding to the voice recognition result to a terminal device to perform the operation. 
     Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  illustrates a voice recognition system according to an embodiment of the disclosure; 
         FIG. 2  is a block diagram illustrating a configuration of a terminal device according to an embodiment of the disclosure; 
         FIG. 3  is a block diagram illustrating a detailed configuration of the terminal device of  FIG. 2  according to an embodiment of the disclosure; 
         FIG. 4  illustrates a method for sharing performance information among a plurality of terminal devices according to an embodiment of the disclosure; 
         FIG. 5  illustrates a method for sharing performance information among a plurality of terminal devices according to an embodiment of the disclosure; 
         FIG. 6  illustrates a method for sharing performance information among a plurality of terminal devices according to an embodiment of the disclosure; 
         FIG. 7  illustrates an embodiment for determining a terminal device, from among terminal devices which receive voice including a triggering word or phrase, to perform voice recognition according to an embodiment of the disclosure; 
         FIG. 8  illustrates various embodiments of performing voice recognition by a server according to an embodiment of the disclosure; 
         FIG. 9  illustrates various embodiments of performing voice recognition by a server according to an embodiment of the disclosure; 
         FIG. 10  illustrates an embodiment of performing voice recognition by a terminal device determined by an edge device according to an embodiment of the disclosure; 
         FIG. 11  illustrates an embodiment of performing voice recognition by an edge device according to an embodiment of the disclosure; 
         FIG. 12  illustrates an embodiment of performing voice recognition by an edge device according to an embodiment of the disclosure; 
         FIG. 13  illustrates an embodiment of changing a device to receive a sound wave for voice recognition when a user utters voice while moving according to an embodiment of the disclosure; 
         FIG. 14  is a flowchart illustrating a controlling method of a terminal device according to an embodiment of the disclosure; and, 
         FIG. 15  is a sequence diagram illustrating a specific operation of the voice recognition system according to an embodiment of the disclosure. 
     
    
    
     Throughout the drawings, like reference numerals will be understood to refer to like parts, components, and structures. 
     DETAILED DESCRIPTION 
     The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of various embodiments of the disclosure as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein can be made without departing from the scope and spirit of the disclosure. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness. 
     The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the disclosure. Accordingly, it should be apparent to those skilled in the art that the following description of various embodiments of the disclosure is provided for illustration purpose only and not for the purpose of limiting the disclosure as defined by the appended claims and their equivalents. 
     It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces. 
     As embodiments may have a variety of modifications and several examples, certain embodiments will be exemplified in the drawings and described in detail in the description thereof. However, this does not necessarily limit the scope of the embodiments to a specific embodiment form. Instead, modifications, equivalents and replacements included in the disclosed concept and technical scope of this specification may be employed. While describing embodiments, if it is determined that the specific description regarding a known technology obscures the gist of the disclosure, the specific description is omitted. 
     In the disclosure, relational terms such as first and second, and the like, may be used to distinguish one entity from another entity, without necessarily implying any actual relationship or order between such entities. In embodiments of the disclosure, relational terms such as first and second, and the like, may be used to distinguish one entity from another entity, without necessarily implying any actual relationship or order between such entities. 
     The terms “include,” “comprise,” “is configured to,” etc., of the description are used to indicate that there are features, numbers, operations, elements, parts or combination thereof, and they should not exclude the possibilities of combination or addition of one or more features, numbers, operations, elements, parts or a combination thereof. 
     According to embodiments, a “module” or “unit” performs at least one function or operation, and may be implemented as hardware or software, or a combination of hardware and software. In addition, a plurality of ‘modules’ or a plurality of ‘units’ may be integrated into at least one module and may be realized as at least one processor except for ‘modules’ or ‘units’ that should be realized in a specific hardware. 
     Hereinafter, embodiments of the disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the disclosure. However, the disclosure may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the disclosure in the drawings, portions which are not related to the description have been omitted, and like reference numerals have been assigned to similar portions throughout the specification. 
     Hereinbelow, embodiments of the disclosure will be further described with reference to drawings. 
       FIG. 1  illustrates a voice recognition system according to an embodiment of the disclosure. 
     Referring to  FIG. 1 , a voice recognition system  1000  according to an embodiment of the disclosure may include a plurality of terminal devices  100 - 1  to  100 - 5 . For example, a first terminal device  100 - 1  (e.g., a smart TV), a second terminal device  100 - 2  (e.g., a smart speaker), and a fifth terminal device  100 - 5  (e.g., a mobile device) may perform direct communication with each other. That is, the first terminal device  100 - 1  may be configured to transmit messages to and/or receive messages from the second terminal device  100 - 2  and the fifth terminal device  100 - 5 , the second terminal device  100 - 2  may be configured to transmit messages to and/or receive messages from the first terminal device  100 - 1  and the fifth terminal device  100 - 5 , and the fifth terminal device  100 - 5  may be configured to transmit messages to and/or receive messages from the first terminal device  100 - 1  and the second terminal device  100 - 2 . Likewise, the second terminal device  100 - 2 , a third terminal device  100 - 3  (e.g., a home appliance), and a fourth terminal device  100 - 4  (e.g., a smart watch) may perform direct communication with each other. 
     While direct communication is described with respect to  FIG. 1 , one or more of the plurality of terminal devices  100 - 1  to  100 - 5  or other terminals not illustrated in  FIG. 1  but included in the voice recognition system  1000  may not establish direct communication while communicating with one or more other terminal devices within the voice recognition system  1000 . For example, one or more of the plurality of terminal devices  100 - 1  to  100 - 5  may perform indirect communication with another terminal device of the voice recognition system  1000  such that any communication may be transmitted between two terminal devices via a third terminal device. For example, if the fifth terminal device  100 - 5  intended to communicate with the third terminal device  100 - 3 , the fifth terminal device  100 - 5  may transmit a message to the second terminal device  100 - 2  and the second terminal device  100 - 2  may transmit the message received from the fifth terminal device  100 - 5  to the third terminal device  100 - 3 . 
     The terminal devices  100 - 1  to  100 - 5  may have a separate and/or different configuration from a server, and may refer to devices directly used by a user  10 . For example, the terminal device may be various electronic devices such as a television (TV), a mobile phone, a smartphone, a personal digital assistant (PDA), a notebook personal computer (PC), a desktop, a tablet PC, an electronic book, and an electronic frame, a kiosk, a refrigerator, a washing machine, a smart speaker, a smart watch, an air conditioner, an audio, a digital video disc (DVD) player, a microwave, an air cleaner, a door lock, a boiler, a closed-circuit television (CCTV), a fire alarm device, a home appliance, a home system or environment regulation device (e.g., heating, ventilation, humidifier, sump pump, water filtration, etc.), or the like. 
     As illustrated in  FIG. 1 , the user  10  may utter a voice (e.g., generate a sound wave) that is intended to trigger a response from one or more of the terminal devices  100 - 1  to  100 - 5  such that the one or more terminal devices  100 - 1  to  100 - 5  perform a function in response based on the generated sound wave ( 0 ), and at least one of the terminal devices  100 - 2  and  100 - 5 , from among a plurality of terminal devices  100 - 1  to  100 - 5 , may receive the sound wave (®). For example, a sound wave generated by user&#39;s voice that is received by the at least one terminal devices  100 - 2  and  100 - 5  may include a triggering word or phrase for activating a function. 
     If at least one terminal device  100 - 2  and  100 - 5  from among the plurality of terminal devices  100 - 1  to  100 - 5  of the voice recognition system  1000  receives the generated sound wave, the terminal device that receives the generated sound wave may forward the sound wave to the appropriate or intended terminal device suitable to perform an operation or function corresponding to the sound wave ( ). For example, as illustrated in  FIG. 1 , the second terminal device  100 - 2  may be both the terminal device that directly receives the sound wave as well as the terminal device that is intended to perform the operation corresponding to the sound wave based on a triggering word or phrase corresponding to the sound wave. Alternatively, the second terminal device  100 - 2  and the fifth terminal device  100 - 5  may receive the sound wave and one or more of the other terminal devices (e.g., terminal devices  100 - 1 ,  100 - 3 , and  100 - 4 ) may be the terminal device that is intended to perform the operation corresponding to the sound wave. As such, the terminal device that receives the sound wave may forward the sound wave or information associated with the sound wave to the intended terminal device such that the intended terminal device may perform the corresponding operation or function based on the sound wave. 
     The plurality of terminal devices  100 - 1  to  100 - 5  may be disposed in close proximity (e.g., within a predetermined space). Here, the predetermined space may be a space within a home such as a “living room”, “a main room”, “a kitchen”, etc. If different users in different spaces generate a sound wave including a triggering word or phrase at the same time, one terminal device in each space may receive a sound wave generated by the different users. 
     Exemplary processes to determine which terminal device of the plurality of terminal devices  100 - 1  to  100 - 5  of the voice recognition system  100  may perform an operation or function based on a sound wave received from one or more users will be described in detail with reference to the accompanying drawings. 
       FIG. 2  is a block diagram illustrating a configuration of a terminal device according to an embodiment of the disclosure. 
     Referring to  FIG. 2 , the terminal device  100  may include a communication interface  110  and a processor  120 . 
     The communication interface  110  may be configured to communicate with various types of external devices according to various types of communication methods. The external device communicating with the terminal device  100  may be a server and/or one or more other terminal devices. 
     Communication with the communication interface  110  with an external device may include communication via a third device (e.g., a repeater, a hub, an access point, a server, or a gateway). The communication interface  110  may be configured to communicate using wireless communication including cellular communication using at least one of the following, for example, long-term evolution (LTE), LTE advanced (LTE-A), a code division multiple access (CDMA), a wideband CDMA (WCDMA), and a universal mobile telecommunications system (UMTS), a wireless broadband (WiBro), or a global system for mobile communications (GSM) and the like. According to one embodiment, the wireless communication may additionally or alternatively include at least one of, for example, wireless fidelity (Wi-Fi), Bluetooth, Bluetooth low energy (BLE), Zigbee, near field communication (NFC), magnetic secure transmission, radio frequency (RF), or body area network (BAN). The communication interface  110  may be configured to communicate using wired communications. Wired communications may include at least one of, for example, a universal serial bus (USB), a high definition multimedia interface (HDMI), a recommended standard 232 (RS-232), a power line communication, or a plain old telephone service (POTS). The network over which the wireless or wired communication is performed may include at least one of a telecommunications network, e.g., a computer network (e.g., local area network (LAN) or wide area network (WAN)), the Internet, or a telephone network. 
     The processor  120  may be configured to control an operation of the terminal device  100 . 
     According to one embodiment, the processor  120  may be implemented as a digital signal processor (DSP), a microprocessor, or a time controller (TCON). However, the disclosure is not limited thereto, and may include or be defined as a central processing unit (CPU), a microcontroller unit (MCU), a micro processing unit (MPU), a controller, an application processor (AP), a communication processor (CP), and an Advanced reduced instruction set computer (RISC) Machines (ARM) processor. The processor  120  may be implemented as a system on chip (SoC), a large scale integration (LSI) with a built-in processing algorithm, or a field programmable gate array (FPGA). 
     In an exemplary embodiment, the processor  120  may share performance information with one or more other terminal devices connected through the communication interface  110 . For example, the processor  120  may transmit the performance information of the terminal device  100  to the one or more other terminal devices through the communication interface  110 , or may receive the performance information of each of the one or more other terminal devices from the one or more other terminal devices. 
     In this case, the performance information transmitted to or received from the one or more other terminal devices may be used for identifying an edge device for determining a terminal device from among a plurality of terminal devices to acquire a voice or sound wave for voice recognition. An edge device may be referred to as a main terminal device, an edge computing device, or the like. The plurality of terminal devices may include the terminal device  100  and one or more other terminal devices. 
     The performance information may include a score (hereinafter referred to as a first score or a performance score (P-score)) obtained based on the performance of each terminal device. 
     For example, a score based on performance is a score obtained by scoring a plurality of criteria, and examples of a plurality of criteria may be as Table 1. 
     
       
         
           
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
             
            
               
                 C 1   
                 Number of Neighboring Devices 
                 Networking Criteria 
               
               
                 C 2   
                 Network IF (Wi-Fi, BT/BLE, etc.) 
               
               
                 C 3   
                 Server Connection 
               
               
                   
                 (Wired/Wireless) 
               
               
                 . . . 
                 . . . 
               
               
                 C k−2   
                 Power Supply (Battery/DC) 
                 Performance Criteria 
               
               
                 C k−1   
                 Computing Power (Processor) 
               
               
                 C k   
                 Computing Power (Memory) 
               
               
                 . . . 
                 . . . 
               
               
                 C n−1   
                 Mobile/Stationary 
                 Stability Criteria 
               
               
                 C n   
                 Stable Time 
               
               
                 . . . 
                 . . . 
               
               
                 C p−1   
                 (Touch) Screen 
                 User Interface Criteria 
               
               
                 C p   
                 Sound/Audio 
               
               
                   
               
            
           
         
       
     
     Referring to Table 1, the processor  120  may obtain a score based on performance on a basis of various criteria such as networking criteria, performance criteria, stability criteria, user interface criteria, or the like. 
     Specifically, the performance information is for determining an edge device and may include whether a device is advantageous for data processing. For example, the networking criteria may include the number of neighboring devices, an operable networking IF, and a server connection via wire or wireless communication, or the like. For example, the terminal device  100  may receive a high score when the number of other connected terminal devices is large, the number of operable networking methods is large, and communication between the server and the terminal device  100  is a wired connection. 
     Alternatively, or additionally, performance criteria may include power supply (e.g., battery vs. DC), processing or computing power (processor, memory), and the like. In an exemplary embodiment, the terminal device  100  may obtain a higher score when power is supplied to the terminal device  100  directly (e.g., via DC connections) rather than from the battery. In another exemplary embodiment, the terminal  100  may obtain a higher score based on the amount of power consumed during processing or interactions with the memory. 
     Alternatively, or additionally, the performance criteria may include a stability criteria such as a mobility factor (e.g., how much a device is changing location), a stationary factor, a stable time, and the like may be considered. When the change in position or movement is not frequent and the stabilization time is longer, the terminal device  100  may be assigned a higher score. 
     Alternatively, or additionally, the user interface criterion may include a relatively auxiliary criterion, and when a touch screen is provided or sound output is available, a high score may be obtained. 
     The processor  120  may evaluate the performance of the terminal device  100  according to one or more of the plurality of criteria and calculate the performance as a score. The processor  120  may obtain a score based on the performance information of the terminal device  100  by summing the scores reflecting the weights according to the importance of each of the plurality of criteria as shown in the following Equation 1.
 
 P   i =Σ k   w   k   C   k   Equation 1
 
     Here, P i  is a first score of the terminal device i, w k  is a weight of the criteria, and C k  may be a score of the criteria. 
     For example, since the performance criteria described above are relatively important, the weights are high, and the user interface criteria are relatively low in importance, so the weights may be low. Also, if the item is not applied, the weight may be zero. 
     The processor  120  may transmit performance information of the terminal device  100  obtained on the basis of various criteria to the one or more other terminal devices as described above. Specifically, the processor  120  may transmit a first score based on the performance information to the one or more other terminal devices. 
     Meanwhile, the processor  120  may receive performance information of the one or more other terminal devices from the one or more other terminal devices. In an exemplary embodiment, the terminal device  100  may receive a first score of the one or more other terminal devices calculated by the one or more other terminal devices, or receive information on the performance of the one or more other terminal devices, and calculate the first score of the one or more other terminal devices by the processor  120 . 
     The performance information received from the one or more other terminal devices may include performance information associated with the terminal devices connected to the one or more other terminal devices. Accordingly, the processor  120  may acquire performance information of not only a 1-hop neighbor device directly connected to the terminal device  100  but also a 2-hop or more neighbor device connected only to the one or more other terminal device (1-hop neighbor device), and identify an edge device including 2-hop or more neighbor device. The operation of sharing the performance information with the one or more other terminal devices will be described in detail with reference to  FIGS. 4 to 6 . 
     The processor  120  may identify the edge device using the performance information of the obtained terminal device  100  and the performance information of the received one or more other terminal devices. Specifically, the processor  120  may identify the terminal device with the highest first score based on performance information as the edge device. 
     In an exemplary embodiment, the edge device may be a local terminal device rather than a server. As the amount of data has drastically increased due to the popularization of the Internet (Internet of things (IoT)) device, cloud computing has faced limitations. The edge device as determined in exemplary embodiments herein may be a device that can implement edge computing technology to overcome the limitations introduced by using a server. In an exemplary embodiment, the edge device may be a device that can perform all or part of the computing tasks performed in a server according to the related art. 
     The edge device identified in this embodiment may determine a device to perform voice recognition from among a plurality of terminal devices. Performing voice recognition may include at least one of an operation of activating a microphone to receive a sound wave, an operation of transmitting information associated with a received sound wave to a server for performing voice recognition, as well as an operation of performing voice recognition by the device that receives the sound wave via a microphone. 
     Based on the performance information, when the terminal device  100  is identified as an edge device, the processor  120  may receive information on the voice reception quality from one or more other terminal devices. For example, the one or more other terminal devices transmitting the information on the sound wave reception quality may be at least one terminal device which has received the sound wave including the triggering word or phrase among the one or more other terminal devices. In an exemplary embodiment, the triggering word or phrase may be a call word or phrase for activating an artificial intelligence (AI) assistant function of the terminal device  100  and may be referred to as a wake-up word, such as “Bixby”, “Siri”, “Okay Google” and “Alexa” or the like. 
     In an exemplary embodiment, the information associated with the sound wave reception quality may be for determining a device to which the sound wave generated by a user is received (e.g., as an input at a receiving device) with the best quality. For example, the information associated with the sound wave reception quality may include a score (hereinafter a second score, or quality score (Q-score)) obtained based on at least one of information on the performance of the microphone in the terminal device  100 , the signal to noise ratio (SNR), the volume associated with the received sound wave, the change rate of the volume of the received sound wave, sound pressure, and information associated with a distance between the user that generated the sound wave and the terminal device  100 . 
     In an exemplary embodiment, the information associated with the distance between the user that generated the sound wave and the terminal device  100  may be obtained by at least one sensor (e.g., sensor  160 ) provided in the terminal device  100 . 
     According to the embodiment, the terminal device  100  may receive the score calculated by the one or more other terminal devices, receive the sound wave signal received by the one or more other terminal devices, and obtain the second score of the one or more other terminal devices by the processor  120 . 
     In an exemplary embodiment, the performance information received from the one or more other terminal devices may include information on the sound wave reception quality of the terminal devices connected to the one or more other terminal devices. Accordingly, the processor  120  may acquire information on the sound wave reception quality of the terminal device (e.g., a 2-hop or more neighbor device) connected only to the one or more other terminal devices without being connected to the terminal device  100 . 
     The processor  120  may determine a device to perform voice recognition based on information on the sound wave reception quality of each of the at least one terminal device that has received the sound wave including the triggering word or phrase. Specifically, the processor  120  may determine a device to perform voice recognition using the second score of the at least one terminal device that has received the sound wave including the triggering word or phrase. 
     Specifically, the processor  120  may determine the terminal device having the highest second score value among the at least one terminal device that has received the sound wave as a device to perform voice recognition. 
     Meanwhile, the processor  120  may determine a device to perform voice recognition including not only information of the sound wave reception quality but also performance information of at least one terminal device which received the sound wave. Then, the processor  120  may transmit a voice recognition command to the determined terminal device. 
     Specifically, the processor  120  may obtain B-score to determine a device which is most suitable to perform voice recognition according to summation of the first score and the second score which reflect the weights according to a degree of importance as shown in the Equation 2 below.
 
 B   i   =w   1   P   i   +w   2   Q   i   Equation 2
 
     Here, P i  is the first score of the terminal device i, w 1  is the weight of the first score, Q i  is the second score of the terminal device i, and w 2  is the weight of the second score. 
     For example, as for a score for determining a device that is most suitable to perform voice recognition, quality of received sound wave is important. When a terminal device which receives a sound wave directly performs voice recognition without transmitting the received sound wave to a server according to an embodiment, performance of a terminal device and the first score may be considered together. When the received sound wave is transmitted to a server, w 1  may be low or zero. 
     In another embodiment, when information associated with the sound wave reception quality is received from a plurality of terminal devices that have received the sound wave, if the difference between the second scores or the B-score between the plurality of terminal devices is within a predetermined value, the processor  120  may determine a terminal device that has transmitted information on the received sound wave reception quality as a voice recognition device. Through this, the real-time property can be secured in the voice recognition process. 
     In the meantime, when the terminal device  100  is an edge device, the processor  120  may determine the terminal device having the highest B-score as a terminal device to perform voice recognition. Then, the processor  120  may transmit a voice recognition command to the determined terminal device. 
     In an exemplary embodiment, when the terminal device  100 , which is an edge device, is a device capable of analyzing the sound wave to discern an intention of the user, the processor  120  may receive the sound wave signal which is input from the device that receives the voice. For example, the voice recognition may include an analysis on the intention of the user. The processor  120  may generate an operation execution command through voice recognition, and may determine a terminal device to perform an operation corresponding to the input sound wave. The processor  120  may transmit a generated operation execution command to the terminal device to perform the operation corresponding to the sound wave. 
     In one embodiment, the processor  120  may determine a device that performs an intention analysis of the sound wave generated by the user, depending on the length of the sound wave. For example, if the length of the sound wave is short, the number of words may be small, or the word corresponding to a specific terminal device may be included, the processor  120  can directly perform the intention analysis of the sound wave generated by the user. The word corresponding to a specific terminal device may be a term mainly used in a terminal device included in the voice recognition system  1000 . For example, “please turn up/down the temperature”, “temperature” is a term mainly used in environmental regulations such as heating, air conditioning, etc. If “temperature” is determined to be included in the sound wave, the processor  120  may directly analyze the intention of the user that generated the sound wave, generate a corresponding control command, and transmit the generated control command to the terminal device that is an air-conditioner. 
     If the length of the sound wave is long or the number of words associated with the sound wave is large, the processor  120  may transmit the received voice signal to the external server for the purpose of analyzing the sound wave generated by the user. For example, the processor  120  may transmit the voice signal (e.g., sound wave) that is input or received at the input device to a server, or receive only length information of the voice signal that is input from the input device and transmit the information on whether to transmit to a server or the terminal device  100  to the device which receives the voice. 
     As described above, even if a plurality of terminal devices simultaneously receives a sound wave generated by a user, by identifying an edge device among a plurality of terminal devices and determining a device for performing voice recognition by the identified edge device, it may be possible to perform an operation corresponding to the sound wave generated by a user only in one terminal device. 
       FIG. 3  is a block diagram illustrating a detailed configuration of the terminal device of  FIG. 2  according to an embodiment of the disclosure. 
     Referring to  FIG. 3 , the terminal device  100  may include a communication interface  110 , a processor  120 , a microphone  130 , a memory  140 , a display  150 , a sensor  160 , and a speaker  170 . 
     Some operations of the communication interface  110  and the processor  120  are the same as those of  FIG. 2 , overlapped description will be omitted. 
     The microphone  130  may receive a sound wave generated by a user. The microphone  130  generates (or converts) a voice or a sound wave received from the outside under the control of the processor  120  into an electrical signal. The electrical signal generated by the microphone  130  may be converted by the processor  120  and stored in the memory  140  or may be transmitted to an external device for performing voice recognition through the communication interface  110 . 
     In an exemplary embodiment, when a sound wave including a triggering word or phrase is received via the microphone  130 , the terminal device to perform voice recognition may be determined as the terminal device  100 . The edge device for determining the device to perform voice recognition may or may not be the terminal device  100 . 
     For example, if the terminal device  100  is an edge device, and when the terminal device  100  is determined as a device to recognize the sound wave based on at least one of the first score and the second score, the processor  120  may perform voice recognition with respect to the sound wave received after identifying that the sound wave includes the triggering word or phrase. 
     In an exemplary embodiment, the processor  120  may transmit the electrical signal associated with the received sound wave, after the triggering word or phrase is identified, to an external server for performing voice recognition. For example, the external server may perform voice recognition, determine a terminal device to generate an operation execution command and perform operation based on the voice recognition result, and transmit an operation performing command to the determined terminal device. 
     If the terminal device  100 , which is an edge device, is a device capable of performing voice recognition, the processor  120  can perform voice recognition on the received sound after the triggering word or phrase is identified. the received sound wave may be received by the terminal device  100  through the microphone  130 , or may be an electrical signal associated with a sound wave which is provided by the one or more other terminal devices. 
     The processor  120  may transmit the voice recognition result to the external server. Based on the voice recognition result, the external server may transmit, to a terminal device to perform an operation corresponding to a voice recognition result from among a plurality of terminal devices, an operation execution command corresponding to the voice recognition result. According to an embodiment of the disclosure, the processor  120  may not transmit the voice recognition result to the external server, but directly transmit the operation execution command corresponding to the voice recognition result to the terminal device that performs the operation corresponding to the voice recognition result, from among the plurality of terminal devices. 
     In the meantime, if the first score of the one or more other terminal devices is higher than the first score of the terminal device  100 , the processor  120  may determine the terminal device having the highest first score among the one or more other terminal devices as the edge device. In an exemplary embodiment, upon receiving a sound wave including the triggering word or phrase via the microphone  130 , the processor  120  may acquire information on the reception quality of the sound wave based on at least a part of the received sound wave. For example, the processor  120  may acquire information on the reception quality based on a sound wave including a triggering word or phrase, a sound wave received for a predetermined time after the triggering word or phrase including the triggering word or phrase, and a sound wave received for a predetermined time after the triggering word or phrase excluding the triggering word or phrase. The information on the reception quality may include the second score. Then, the processor  120  may control the communication interface  110  to transmit information on the acquired reception quality to the edge device. 
     At this time, if the acquired reception quality is less than a preset criteria, the processor  120  may discard information on the acquired reception quality without transmitting the information to the edge device. Specifically, if the acquired second score is less than a predetermined value, the processor  120  may discard the acquired second score without transmitting the second score to the edge device. 
     The memory  140  may store various programs and data necessary for the operation of the terminal device  100 . For example, at least one instruction may be stored in the memory  140 . The processor  120  may perform the operations described above by executing instructions stored in the memory  140 . The memory  140  may be implemented as a non-volatile memory, a volatile memory, a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD). 
     The learned AI model may be stored in the memory  140 . In an exemplary embodiment, the learned AI model may be learned to recognize the received sound wave and convert the sound wave into text, or to determine the intention of the user based on the sound wave. As such, if the learned AI model for voice recognition is stored in the memory  140 , the processor  120  may perform voice recognition using the stored AI model without transmitting the electrical signal associated with the received sound wave to an external server for performing voice recognition. 
     The display  150  may display various information under the control of the processor  120 . In an exemplary embodiment, the display  150  may be implemented as a touch screen together with a touch panel. According to various embodiments, the display  150  may not be provided in the terminal device  100 . For example, when the terminal device  100  is a smart speaker or the like, the display  150  may not be provided. 
     The sensor  160  may sense various status information of the terminal device  100  or the user. For example, the sensor  160  may include a motion sensor (e.g., a gyro sensor, an acceleration sensor, or the like) capable of sensing motion information of the terminal device  100 , a sensor capable of sensing location information (e.g., a global positioning system sensor), a sensor capable of sensing environmental information (e.g., a temperature sensor, a humidity sensor, an air pressure sensor, an ultrasonic sensor, and an infrared sensor, etc.), and a sensor capable of sensing biological user information of the terminal device  100  (e.g., a blood pressure sensor, a blood glucose sensor, a pulse rate sensor, etc.), or the like. In addition, the sensor  160  may further include an image sensor (e.g., a camera) for photographing or capturing images of the environment outside of the terminal device  100 . 
     The processor  120  may determine whether the user moves according to a distance and a change in distance between the user and the terminal device  100 , based on various sensed values by the sensor  160 . In an exemplary embodiment, the processor  120  can acquire information on the voice reception quality based on the distance between the user and the terminal device  100 . 
     The speaker  170  may have a configuration to output various kinds of notification sounds or voice messages as well as various audio data for which various processing jobs such as decoding, amplification, noise filtering, etc. are performed by the audio processor. In particular, the speaker  170  may output a response to a sound wave generated by a user as a voice message in a natural language format. The configuration to output audio may be implemented as a speaker, but this can be implemented as an output terminal capable of outputting audio data. 
       FIGS. 4, 5, and 6  illustrate a method for sharing performance information among a plurality of terminal devices according to an embodiment of the disclosure. 
     Specifically,  FIG. 4  illustrates a method of sharing performance information when a new device accesses a voice recognition system. Here, a TV  400 - 1 , a speaker  400 - 2 , and a refrigerator  400 - 3  are already connected to the network and may be in a state of sharing information with each other. 
     Referring to  FIG. 4 , when a new terminal device  400 - 4  accesses a network, the new terminal device  400 - 4  may transmit an information request signal to at least one of a plurality of terminal devices connected to the network in operation S 401 . In an exemplary embodiment, the new terminal device  400 - 4  may transmit an information request signal in a multicast method. The new terminal device  400 - 4  may transmit performance information associated with the new terminal device  400 - 4  including the P-score to the other terminal device together with the information request signal or separately. 
     In an exemplary embodiment, the speaker  400 - 2  and the refrigerator  400 - 3 , which are terminal devices receiving the request from the new terminal device  400 - 4 , may transmit own performance information including the P-score to the new terminal device  400 - 4  in operations S 402  and S 403 . 
     The new terminal device  400 - 4  may request a device list  410  to at least one of the plurality of terminal devices connected to the network in operation S 404 . In an exemplary embodiment, the device list  410  may be a list recording of other terminal devices capable of communicating. The new terminal device  400 - 4  may request the device list  410  to all of the one or more other terminal devices that transmit the performance information, or request the device list  410  to the one or more other terminal devices having the highest performance based on the performance information received from the one or more other terminal devices. Although it has been described above that the device list  410  is requested after receiving the performance information, the device list  410  may be requested simultaneously in an exemplary embodiment. 
     The new terminal device  400 - 4  may receive the device list  410  of the speaker from the speaker  400 - 2  which is the other terminal device in operation S 405 . For example, the device list  410  of the speaker may include information associated with the one or more other terminal devices capable of communicating with the speaker  400 - 2 . Therefore, the device list  410  may include information associated with the one or more other terminals device not communicating with the new terminal device  400 - 4 . 
     As an embodiment, in  FIG. 4 , information associated with the TV  400 - 1  that communicates with the speaker  400 - 2  in the device list  410  of the speaker but does not communicate with the new terminal device  400 - 4  may be included. Accordingly, the new terminal device  400 - 4  may acquire information associated with the one or more other terminal devices not directly communicating with each other. 
     The device list  410  may include information on ID, name, address, performance information (P-score), direct communication (1-Hop), or the like. 
     Accordingly, as shown in  FIG. 5 , each of the plurality of terminal devices  400 - 1  to  400 - 4  connected to the network may share information of the one or more other terminal devices. Each of the plurality of terminal devices  400 - 1  to  400 - 4  may identify an edge device among the plurality of terminal devices  400 - 1  to  400 - 4  based on the shared performance information. 
     Referring to  FIG. 5 , each of the plurality of terminal devices  400 - 1  to  400 - 4  may identify the TV  400 - 1  having the highest P-score as an edge device. 
     In an exemplary embodiment, each of the plurality of terminal devices  400 - 1  to  400 - 4  may update the shared performance information if the predetermined condition is satisfied. For example, each of the plurality of terminal devices  400 - 1  to  400 - 4  may update the shared performance information according to a predetermined cycle or update the shared performance information when the new terminal device  400 - 4  requests performance information. In an exemplary embodiment, each terminal device may identify a new edge device based on the updated performance information. For example, each terminal device may identify a new edge device each time the performance information is updated, and if there is a terminal device having a P-score higher than the P-score of the terminal device identified as the current edge device, may identify the terminal device having a higher P-score as a new edge device. 
     Alternatively, as shown in  FIG. 6 , when the new terminal device  400 - 4  that is connected to the network is out of communication with the voice recognition system, the shared performance information can be updated. For example, each of the plurality of terminal devices  400 - 1  to  400 - 3  can delete information about the new terminal device  400 - 4  that is out of communication with the voice recognition system from the device list  410 . 
     When the edge device is out of communication with the voice recognition system, each terminal device may identify a new edge device based on the shared performance information. 
       FIGS. 4, 5, and 6  merely illustrate an embodiment of identifying an edge device based on performance information of a plurality of terminal devices, but in various embodiments, an edge device may be identified through input of a manipulation to select an edge device by a user. 
     In consideration of the disabled state of the identified edge device the next-ranked edge device candidates can be selected together at the time of identifying the edge device. In an exemplary embodiment, the next-ranked edge device candidate may be a terminal having second highest score based on the performance information, or may be identified by the user&#39;s selection. Accordingly, when the identified edge device is in the disabled state such as power-off or failure, the automatically determined next-ranking edge device candidate may be changed to the edge device without performing the edge device identification process again. 
       FIG. 7  illustrates an embodiment for determining a terminal device to perform voice recognition among terminal devices receiving a voice including a triggering word or phrase according to an embodiment of the disclosure. 
     First,  FIG. 7  illustrates an embodiment in which the TV  700 - 1  having the highest P-score of 200 may be identified as an edge device in accordance with performance information sharing among a plurality of terminal devices  700 - 1  to  700 - 5  (e.g., TV  700 - 1 , refrigerator  700 - 2 , smart watch  700 - 3 , mobile device  700 - 4 , and smart speaker  700 - 5 ) connected to the network. 
     Referring to  FIG. 7 , when the user  10  utters the triggering phrase “Hi, Bixby”, a smart watch  700 - 3 , a mobile device  700 - 4 , and a smart speaker  700 - 5 , from among the plurality of terminal devices  700 - 1  to  700 - 5  may receive the sound wave generated by the user including the triggering phrase. 
     In an exemplary embodiment, each of the smart watch  700 - 3 , the mobile device  700 - 4 , and the smart speaker  700 - 5  that has received the sound wave including the triggering phrase may acquire information on the reception quality of the sound wave based on at least one of a microphone performance, a volume of the received sound wave, a rate of change of the volume of the received sound wave, the sound pressure, and the distance prediction with the user that generated the sound wave. In an exemplary embodiment, the information associated with the reception quality may include a Q-score indicating the reception quality of the sound wave. 
     Each terminal device that has received the sound wave including the triggering phrase can transmit information on the obtained reception quality to the TV  700 - 1  which is the edge device. If the acquired voice reception quality is less than a predetermined level, the terminal device that has received the sound wave including the triggering word can discard or disregard the information associated with the reception quality without transmitting the information to the edge device. For example, if the predetermined reference value of the Q-score for the reception quality is 15, as shown in  FIG. 7 , the smart watch  700 - 3  having the acquired Q-score which is less than 15 may delete the information associated with the reception quality, without transmitting the reception quality information to the TV  700 - 1  which is the edge device. 
     The TV  700 - 1  which receives the reception quality information from the mobile device  700 - 4  and the smart speaker  700 - 5  as one or more other terminal devices may determine a device for performing voice recognition based on performance information of the mobile device  700 - 4  and the smart speaker  700 - 5  and reception quality information. In an exemplary embodiment, the meaning of performing voice recognition may be an operation of transmitting an electrical signal corresponding to the received sound wave to the server for voice recognition, or an operation of performing voice recognition by the terminal itself. 
     In an exemplary embodiment, the TV  700 - 1  which is the edge device may determine a device to perform voice recognition using at least one of a P-score, which is a score for performance information, and a Q-score, which is a score for reception quality. The edge device can reflect the weight to each of the P-score and the Q-score and then add the sum, which may vary according to the embodiment. For example, if the voice recognition is performed by the device receiving the sound wave generated by the user, the performance information is also important. Therefore, the weight of the P-score may be increased. If voice recognition is performed in an external server, only reception quality may be important and the weight of the P-score may be lower. 
     The edge device which determines a device to perform voice recognition based on performance information and reception quality may transmit a voice recognition execution command to the determined terminal device. 
     For example, if the weights of the P-score and the Q-score are respectively  1 , the TV  700 - 1  may transmit the voice recognition execution command to the mobile device  700 - 4  having the highest sum of the P-score and the Q-score. The mobile device  700 - 4  receiving the voice recognition execution command can perform voice recognition on the portion of the sound wave following the triggering word or phrase. For example, the mobile device  700 - 4  may transmit a sound wave including the phrase “Please turn on a song on a speaker”, which is provided after a sound wave including the triggering phrase “Hi, Bixby” is received, to a server for voice recognition, or perform voice recognition by itself. 
     In the above description, the TV  700 - 1 , which is the edge device, can recognize a sound wave including the triggering word or phrase, and the TV  700 - 1  as the edge device may be determined as a voice recognition performing device, according to the embodiment. Various embodiments of the voice recognition subject will be described in detail with reference to  FIGS. 8, 9, 10, 11, and 12 . 
     Meanwhile, according to the embodiment, information on the reception quality can be transmitted to the edge device at a predetermined cycle. For example, when the user  10  generates a sound wave while moving, the plurality of terminal devices receiving the sound wave of the user  10  may transmit information on the reception quality associated with the received sound wave to the edge device in a predetermined cycle. Accordingly, the device for performing voice recognition may be changed during the duration of the sound wave. 
     Specifically, when the reception quality of the terminal device determined as a device performing voice recognition is degraded, the edge device may change the terminal device to perform voice recognition. For example, the plurality of terminal devices receiving the sound wave generated by the user  10  may transmit information on the reception quality to the edge device at a predetermined cycle, or if the second score of the terminal device which is determined as a device to perform voice recognition is reduced to less than a predetermined value, the edge device may request information on the reception quality to the plurality of terminal devices which receive the electrical signal associated with the sound wave generated by the user  10  and receive information on the reception quality of the plurality of terminal devices receiving the voice of the user  10 . At this time, the edge device can change the terminal device having the highest second score among the plurality of terminal devices to a device for performing voice recognition. 
     That is, voice recognition of the sound wave that is generated prior to a change of the terminal device to perform voice recognition is performed by the terminal device before change, and a portion of the sound wave received after the change may be recognized by the changed terminal device. For example, the terminal devices for performing voice recognition before change and after change, respectively, may transmit electrical signals associated with the received sound wave to a server or an edge device for voice recognition. According to still another embodiment, if the terminal devices for performing voice recognition before change and after change transmit the received voice to the edge device respectively, the edge device may stitch the received portions of the sound wave into one sound wave, transmit the stitched one sound wave to a server for voice recognition, or the edge device may directly perform voice recognition. In an exemplary embodiment, the edge device may transmit information associated with a device to perform an operation corresponding to voice recognition to the server, taking account of accounts of terminal devices that have transmitted the electrical signals corresponding to the received sound wave. 
     As described above, even if the sound wave generated by the user is received at a plurality of terminal devices, only one device performs voice recognition, unnecessary resource consumption can be reduced, and conflict among devices in performing an operation with respect to a user&#39;s voice command may be prevented. 
       FIGS. 8 and 9  are views for describing various embodiments in which voice recognition is performed by a server according to an embodiment of the disclosure. 
       FIGS. 8 and 9  illustrate that the TV  800 - 1  having the highest P-score is identified as the edge device in accordance with sharing of performance information of a plurality of terminal devices  800 - 1  to  800 - 3  connected to the network, and the mobile device  800 - 2  is determined as a device to perform voice recognition by the TV  800 - 1 . 
     Referring to  FIG. 8 , the mobile device  800 - 2  receiving the portion of the sound wave after the triggering word or phrase “Turn on the music on the speaker”, may transmit the electrical signal corresponding to the received sound wave to the server  200  for perform voice recognition ({circle around ( 1 )}). 
     The server  200  may perform voice recognition on the received electrical signal corresponding to the sound wave to determine a terminal device to generate an operation execution command and perform an operation command corresponding to the sound wave ({circle around ( 2 )}). For example, as a result of voice recognition, the server  200  may determine a smart speaker  800 - 3  as a terminal device to generate a music reproduction command and perform the operation command. The server  200  may transmit the generated operation execution command to the smart speaker  800 - 3  ({circle around ( 3 )}). 
     The smart speaker  800 - 3  receiving the operation command from the server  200  can perform an operation corresponding to the received command ({circle around ( 4 )}). For example, the smart speaker  800 - 3  can reproduce music based on the received reproduction command. 
     While the user  10  has generated a sound wave including the subject of the operation, if the user  10  further says “please turn on the music”, the server  200  may determine a terminal device to perform an operation command based on various criteria. For example, a terminal device having the closest distance from the user  10  or a terminal device with the best audio output performance may be determined as a device to perform an operation command, and an operation command may be transmitted. 
     As illustrated in  FIG. 9 , when a plurality of terminal devices is determined as terminal devices to perform an operation command, a device to perform a final operation may be determined according to a user&#39;s selection. 
     Referring to  FIG. 9 , the server  200  may perform voice recognition on the electrical signal associated with received sound wave generated by the user  10  ({circle around ( 1 )}) from the mobile device  800 - 2  ({circle around ( 2 )}). As a result of performing voice recognition, if it is determined that voice recognition is performed by a plurality of terminal devices, the server  200  may transmit an operation execution command to the determined plurality of terminal devices  800 - 2  and  800 - 3  ({circle around ( 3 )}). 
     In this case, the user  10  can be requested to select one of the plurality of terminal devices  800 - 2  and  800 - 3  ({circle around ( 4 )}). For example, the terminal device requesting the user  10  to select one device may be at least one of the plurality of terminal devices  800 - 2  and  800 - 3 . 
     If the user  10  selects one device according to the selection request ({circle around ( 5 )}), the selected device can perform an operation command corresponding to the sound wave generated by the user ({circle around ( 6 )}). For example, when the user  10  selects the smart speaker  800 - 3  among the mobile device  800 - 2  and the smart speaker  800 - 3  which receive the operation execution command, the selected smart speaker  800 - 3  may reproduce music according to the received operation command. 
     In the above description, it is described that the server  200  transmits an operation execution command to a plurality of the determined terminal devices  800 - 2  and  800 - 3 . However, in an alternative embodiment, if it is determined that the plurality of terminal devices perform voice recognition, the server  200  may transmit a command for the terminal device selection request to the device  800 - 2  that has transmitted the voice signal, and if the device  800 - 2  that has transmitted the electrical signal associated with the received sound wave transmits a response to the user&#39;s selection to the server  200 , the server  200  may be configured to transmit an operation execution command to the selected terminal device. 
     Hereinabove, an embodiment of performing a voice recognition operation regarding the received voice is performed by an external server is described. Hereinbelow, an embodiment of performing a voice recognition by a terminal device will be described. 
       FIG. 10  is a view for describing an embodiment in which voice recognition is performed by the terminal device determined by the edge device according to an embodiment of the disclosure. 
       FIG. 10  illustrates an embodiment after the TV  800 - 1  having the highest P-score is identified as the edge device in accordance with sharing of performance information of the plurality of terminal devices  800 - 1  to  800 - 3  connected to the network, and the mobile device  800 - 2  is determined as a device for performing voice recognition by the TV  800 - 1 . 
     Referring to  FIG. 10 , the mobile device  800 - 2  which receives the sound wave corresponding to the phrase “please turn on music on the speaker”, which is a sound wave received after a triggering word or phrase is uttered by the user  10 , may perform voice recognition regarding the received sound wave ({circle around ( 1 )}). 
     Specifically, the mobile device  800 - 2  may perform voice recognition on the received sound wave and determine a terminal device to generate an operation execution command corresponding to a sound wave and perform an operation command. For example, the mobile device  800 - 2  may generate a music reproduction command in accordance with the intention of the user  10  as a result of voice recognition, and determine the smart speaker  800 - 3  as the terminal device to perform the operation command. Then, the mobile device  800 - 2  may transmit the generated operation execution command to the smart speaker  800 - 3  ({circle around ( 2 )}). 
     The smart speaker  800 - 3  receiving the operation command from the mobile device  800 - 2  can perform an operation corresponding to the received command ({circle around ( 3 )}). For example, the smart speaker  800 - 3  may reproduce music based on the received reproduction command. 
     In the above description, the user  10  has generated the sound wave including the subject of performing the operation, but if the user generates a sound wave corresponding to the phrase “please turn the music”, the mobile device  800 - 2  may determine the terminal device to execute the command based on various criteria. For example, a terminal device having the closest distance from the user  10  or a terminal device with the best audio output performance may be determined as a device to perform an operation command, and an operation command may be transmitted. Therefore, the mobile device  800 - 2  that has performed the voice recognition may be determined as a device to execute an operation command. In this case, the mobile device  800 - 2  may directly provide the user  10  with a response corresponding to the voice recognition result. 
     In the meantime, if a plurality of terminal devices is determined as the terminal devices to perform the operation command, the mobile device  800 - 2  may request a user  10  to select a device, and determine a device to perform a final operation. 
       FIGS. 11 and 12  illustrate an embodiment in which voice recognition is performed by the edge device according to an embodiment of the disclosure. 
     First,  FIGS. 11 and 12  illustrate an embodiment after the TV  800 - 1  having the highest P-score is identified as the edge device in accordance with sharing of performance information of the plurality of terminal devices  800 - 1  to  800 - 3  connected to the network, and the mobile device  800 - 2  is determined as a device to perform voice recognition by the TV  800 - 1 . 
     Referring to  FIG. 11 , the mobile device  800 - 2  that has received the sound wave generated by the user after the triggering word or phrase is uttered by the user  10 , “Please turn on music on the speaker” may transmit the received voice signal to the TV  800 - 1 , which is the edge device for performing voice recognition ({circle around ( 1 )}). 
     The TV  800 - 1  as the edge device may perform voice recognition of the received sound wave to determine a terminal device to generate an operation command corresponding to the sound wave and to perform an operation command ({circle around ( 2 )}). For example, the TV  800 - 1 , which is the edge device, may generate a music reproduction command in accordance with the utterance intention of the user  10  as a result of voice recognition, and determine the smart speaker  800 - 3  as a terminal device to perform an operation command. Then, the TV  800 - 1  as the edge device may transmit the generated operation execution command to the smart speaker  800 - 3  ({circle around ( 3 )}). 
     The smart speaker  800 - 3  which receives the operation command from the TV  800 - 1  which is the edge device may perform an operation corresponding to the received command ({circle around ( 4 )}). For example, the smart speaker  800 - 3  may reproduce music based on the received reproduction command. 
     In the above description, the user  10  has generated a sound wave including the subject of the operation, but when the user  10  generates a sound wave associated with the phrase “turn on the music”, the TV  800 - 1 , which is the edge device, may determine a terminal device to perform an operation command. For example, a terminal device having the closest distance from the user  10  or a terminal device with the best audio output performance may be determined as a device to execute an operation command, and an operation command may be transmitted. Therefore, the TV  800 - 1 , which is the edge device, may be determined as a device to perform an operation command. In this case, the TV  800 - 1  as the edge device can directly provide the user  10  with a response corresponding to the voice recognition result. 
     When the plurality of terminal devices is determined as the terminal devices to perform an operation command, the mobile device  800 - 2  may request the user  10  to select a device and determine a device to perform final operation according to selection of the user  10 . 
     When the terminal device  800 - 4  to perform the operation command corresponding to the sound wave generated by the user  10  determined by the TV  800 - 1  as the edge device is not a terminal device directly communicating with the TV  800 - 1  as the edge device, as illustrated in  FIG. 12 , an operation execution command may be transmitted to the terminal device  800 - 3  which is connected to both the TV  800 - 1  which is the edge device and the terminal device  800 - 4  to perform the operation command. 
     This operation may be possible by sharing information of each terminal device. The operation of  FIG. 12 , when the mobile device  800 - 2  performing voice recognition determines a terminal device to perform an operation command, may be applied to a case where a terminal device not directly communicating with the mobile device  800 - 2  is determined as a device to perform an operation execution command. 
       FIG. 13  illustrates an embodiment of changing a device to receive a sound wave for voice recognition when a first user  10  utters the sound wave while moving according to an embodiment of the disclosure. 
     Referring to  FIG. 13 , when the first user  10  generates a sound wave including a triggering word or phrase (e.g., wake-up word or phrase) ({circle around ( 1 )}) and a first terminal device  1300 - 1  receives the sound wave generated by the user, the first terminal device  1300 - 1  may be activated according to the reception of the sound wave including the triggering word, and may recognize the speaker (e.g., the user that generated the sound wave) of the received sound wave ({circle around ( 2 )}). In an exemplary embodiment, the first terminal device  1300 - 1  may be one terminal device that has received the voice of the first user  10 , or a selected terminal device that has acquired the sound wave for voice recognition among a plurality of terminal devices that have received the sound wave generated by the user. 
     Thereafter, when the sound quality of the sound wave received by the first terminal device  1300 - 1  is reduced, the first terminal device  1300 - 1  may transmit a wake-up request to peripheral devices  1300 - 2  to  1300 - 4 . In an exemplary embodiment, the sound quality of the sound wave received at the first terminal device  1300 - 1  may be reduced due to the movement of the first user  10 . 
     Then, the first terminal device  1300 - 1  may transmit the information associated with the recognized sound wave together with the activation request ({circle around ( 3 )}). Accordingly, even if a sound wave generated by a second user  20  is recognized in the activated second terminal device  1300 - 2 , the second terminal device  1300 - 2  may not perform the operation for the voice recognition of the second user  20 . 
     In an exemplary embodiment, after the peripheral devices  1300 - 2  to  1300 - 4  are activated, the peripheral devices may transmit a control command to minimize an operation noise to at least some terminal devices from among the peripheral devices to minimize noise of a surrounding environment. 
     For example, when the noise of the surrounding environment is equal to or greater than a preset value, the activated third terminal device  1300 - 3  may request a low noise operation mode to the fourth terminal device  1300 - 3  and the fifth terminal device  1300 - 5  having a big operation noise ({circle around ( 4 )}). Accordingly, the fourth terminal device  1300 - 4  (e.g., an air conditioner) may be changed to a silent or still air mode and the fifth terminal device  1300 - 5  (e.g., a robot cleaner) may be changed to the low noise cleaning mode ({circle around ( 5 )}). 
     When noise of a surrounding environment is less than a preset value, the activated third terminal device  1300 - 3  may omit an operation to request a low noise operation mode to other terminal devices. 
     Thereafter, when the first user  10  generates a sound wave associated with the phrase “news briefing” ({circle around ( 6 )}), from among the first terminal device  1300 - 1  which is a smart speaker capable of news briefing operation among the terminal devices  1300 - 1  to  1300 - 4  receiving the sound wave generated by the first user  10  and the third terminal device  3   1300 - 3  which is a smart TV, the smart TV  1300 - 3  having good reception quality may perform an operation corresponding to sound wave and voice recognition of the first user  10 . 
     When the first user  10  generates a sound wave associated with the phrase “Turn on a still air mode” ({circle around ( 7 )})”, among the terminal devices  1300 - 1  to  1300 - 4  receiving the sound wave generated by the first user  10 , the fourth terminal device  1300 - 4  capable of operating in still air mode may perform an operation corresponding to the voice recognition based on the sound wave generated by the first user  10 . 
     When the reception quality of the sound wave received by the fourth terminal device  1300 - 4  activated by the first terminal device  1300 - 1  is less than a preset value as the first user  10  generates the sound wave while moving, the fourth terminal device  1300 - 4  may transmit the information on the recognized utterance and/or the recognized user together with the activation request to the peripheral terminal devices. 
     As described above, by receiving the triggering word or phrase and requesting the activated terminal device to activate the peripheral terminal devices in accordance with the movement of the first user, the first user  10  may control various devices with voice commands without repeatedly uttering the triggering word or phrase, thereby improving convenience of a user recognition performance and voice recognition performance. 
     If the first user  10  does not utter the triggering word for deactivating the voice recognition function of the terminal device or does not generate a sound wave for a predetermined time, the terminal device may terminate the voice recognition function. For example, if the first user  10  utters a triggering word or phrase for deactivating the voice recognition function such as “Bye, Bixby” or does not generate a sound wave over a predetermined time, the terminal can end the voice recognition function. 
       FIG. 14  is a flowchart to describe a controlling method of a terminal device according to an embodiment of the disclosure. 
     Referring to  FIG. 14 , a terminal device may receive performance information of one or more other terminal devices from each of the one or more other terminal devices in operation S 1401 . In an exemplary embodiment, the received performance information may include information about a terminal device that is in communication with the other terminal device but does not communicate with the terminal device. 
     The terminal device may identify the edge device based on the received performance information in operation S 1402 . For example, the edge device may be a device for determining a device to perform voice recognition among a plurality of terminal devices. The edge device may be determined in consideration of processing performance, computing performance, movement status, or the like. 
     If the terminal device is identified as the edge device according to the aforementioned criteria in operation S 1403 -Y, the terminal device may receive, from other terminal devices receiving the triggering word, information on the reception quality in operation S 1404 . 
     The terminal device may determine a terminal device to acquire a sound wave generated by a user for voice recognition based on performance information of the other terminal device and information on the reception quality in operation S 1405 . In an exemplary embodiment, the terminal device for performing voice recognition may be a device for acquiring a sound wave generated by a user for voice recognition. The terminal device may transmit a voice recognition execution command to the one or more other terminal devices determined to perform voice recognition. 
     When the terminal device is not the edge device in operation S 1403 -N, if the terminal device receives a sound wave including the triggering word or phrase, information associated with the reception quality of the sound wave can be transmitted to the terminal device determined as the edge device in operation S 1406 . For example, the information associated with the voice reception quality may be obtained based on the received sound wave generated by the user. In an exemplary embodiment, if the voice reception quality is less than the preset level, the terminal device can discard the information associated with the reception quality of the sound wave without transmitting the information associated with the reception quality of the sound wave to the edge device. 
     Thereafter, upon receiving a voice recognition command from the edge device, the terminal device can perform voice recognition on the sound wave after the sound wave following the triggering word or phrase. For example, voice recognition may refer to an operation of transmitting a received sound wave generated by a user to a server for voice recognition or an operation of the terminal device performing voice recognition to determine the user&#39;s intention associated with the sound wave. 
     As described above, even though a plurality of terminal devices has received the sound wave generated by the user, a single device determined by the edge device may perform voice recognition, and accordingly, unnecessary resource consumption may be reduced and collision between devices in performing an operation on a command included in the sound wave generated by the user may be prevented. 
       FIG. 15  illustrates an operation of the voice recognition system according to an embodiment of the disclosure. 
     Referring to  FIG. 15 , the voice recognition system  1000  of the disclosure may include the plurality of terminal devices  100 - 1  to  100 - 4  and the server  200 . In an exemplary embodiment, the server  200  may include a configuration to determine the user&#39;s intention through voice recognition. If voice recognition is possible by the terminal device, the server  200  may be omitted. 
     The plurality of terminal devices  100 - 1  to  100 - 4  in the voice recognition system  1000  may share performance information and determine the edge device in operation S 1501 . In  FIG. 15 , the first terminal device  100 - 1  is the edge device. 
     Thereafter, when a sound wave generated by the user including the triggering word or phrase is received by at least one of the plurality of terminal devices  100 - 1  to  100 - 4 , the at least one terminal device that has received the sound wave including the triggering word may transmit the reception quality information associated with the received sound wave to the edge device  100 - 1 . In an exemplary embodiment, the reception quality information may be a Q-score obtained by at least one terminal device that has received the sound wave including the triggering word or phrase, and may be the received sound wave. In an exemplary embodiment, the score for the reception quality of each terminal device may be calculated by the edge device. 
     For example, when the second terminal device  100 - 2  and the third terminal device  100 - 3  of the plurality of terminal devices  100 - 1  to  100 - 4  receive the sound wave generated by the user including the triggering word or phrase in operation S 1502 , the second terminal device  100 - 2  and the third terminal device  100 - 3  may transmit the reception quality information to the edge device  100 - 1  in operations S 1503 , S 1504 . 
     The first terminal device  100 - 1  as the edge device may determine the voice recognition device based on the information on the received voice reception quality in operation S 1505 . For example, the voice recognition device may be a device for acquiring a sound wave generated by a user for voice recognition. The first terminal device  100 - 1  as the edge device may transmit a voice recognition command to the terminal device to perform the determined voice recognition. For example, if the second terminal device  100 - 2  is determined as a terminal device for performing voice recognition, the first terminal device  100 - 1  may transmit a voice recognition command to the second terminal device in operation S 1506 . 
     Even after the sound wave including the triggering word or phrase is received by the second terminal device  100 - 2  and the third terminal device  100 - 3  in operation S 1507 , only the second terminal device  100 - 2  which receives the voice recognition command may transmit the received sound wave to the server  200  in operation S 1508 . In  FIG. 15 , although operations S 1502  and S 1507 , which are first sound wave and second sound wave receiving operations respectively, are shown as separate operations, in actual implementation, the operations may be continuous operations, and operation S 1507  may be performed simultaneously with operations S 1503  to S 1506 . For example, S 1502  and S 1507  may be a single sound wave generated by a user. 
     The server  200  may perform voice recognition of the received sound wave and may determine a device to perform an operation corresponding to the sound wave in operation S 1509 . For example, the server  200  may generate an operation command corresponding to the sound wave based on the voice recognition result, and determine the terminal device to perform the operation command. 
     The server  200  may transmit the generated operation execution command to the terminal device determined to execute the operation command. For example, if the terminal device determined to perform the operation command is the fourth terminal device  100 - 4 , the server  200  may transmit the operation execution command to the fourth terminal device  100 - 4  in operation S 1510 . The fourth terminal device  100 - 4  receiving the operation execution command can perform an operation corresponding to the command in operation S 1511 . 
     As described above, even though a plurality of terminal devices have received the sound wave generated by the user, one device determined by the edge device may perform voice recognition, and transmits an operation execution command to only one terminal device according to the result of voice recognition, and thus, unnecessary resource consumption may be reduced, and conflict among devices in performing an operation for a command included in the sound wave generated by the user may be prevented. 
     Meanwhile, the various embodiments described above can be implemented in a recording medium that can be read by a computer or a similar device using software, hardware, or a combination thereof. In accordance with a hardware implementation, the embodiments described in the disclosure may be implemented using at least one of application specific integrated circuits (ASICs), DSPs, digital signal processing devices (DSPDs), programmable logic devices (PLDs), FPGAs, processors, controllers, microcontrollers, microprocessors, and an electrical unit for carrying out other functions. In some cases, the embodiments described herein may be implemented by the processor itself. According to a software implementation, embodiments such as the procedures and functions described herein may be implemented with separate software modules. Each of the software modules may perform one or more of the functions and operations described herein. 
     Meanwhile, the method according to various embodiments of the disclosure described above may be stored in a non-transitory readable medium. Such non-transiently readable media may be used in various devices and used. 
     Non-volatile computer readable medium means a medium that stores data for a short period of time such as a register, a cache, a memory, etc., but semi-permanently stores data and can be read by a device. Specific examples of non-transitory computer readable media include compact disc (CD), DVD, hard disk, Blu-ray disk, USB, memory card, read only memory (ROM), etc. 
     According to one embodiment, a method according to various embodiments disclosed herein may be provided in a computer program product. A computer program product may be traded between a seller and a purchaser as a commodity. A computer program product may be distributed in the form of a machine readable storage medium (e.g., CD-ROM) or distributed online through an application store (e.g.: PlayStore™). In the case of on-line distribution, at least a portion of the computer program product may be stored temporarily or at least temporarily in a storage medium such as a manufacturer&#39;s server, a server in an application store, or a memory in a relay server. 
     While the disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims and their equivalents.