Patent Publication Number: US-2013252555-A1

Title: Apparatus and method for link setup using electric field

Description:
CLAIM OF PRIORITY 
     This application claims priority under 35 U.S.C. §119 to an application filed in the Korean Intellectual Property Office on Mar. 20, 2012 and assigned Serial No. 10-2012-0028298, the contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclose relates generally to short range communications, and in particular, to an apparatus and method for performing short range wireless communications. 
     2. Description of the Related Art 
     Due to the development of communication technologies, a communication system now supports various communication schemes including both voice and data services as well as a high-capacity multimedia service. In addition, the communication system also supports a short range communication scheme for sharing information between adjacent electronic devices, such as Near Field Communication, Wireless Local Area Network (WLAN), Bluetooth, and Infrared Data Association (IrDA). 
     When setting up a communication link through a short range communication scheme, an electronic device may face a communication link setup delay due to various connection setup operations required in the short range communication scheme. For example, when setting up a communication link by using a Bluetooth communication scheme, an electronic device enters into an inquiry substate and initiates a device search process and a connection setup process in order to search another electronic device. In this case, when the electronic device fails to search another electronic device or when the preceding inquiry substate is not interrupted, the electronic device may experience a delay for performing the inquiry substate for 10.24 seconds, for example, according to the Bluetooth standard. 
     Therefore, there is a need for an improved scheme to establish a connection in a short range wireless communications. 
     SUMMARY OF THE INVENTION 
     Objects of the present disclose are to substantially solve at least the above problems and/or disadvantages and to provide at least the advantages below. Accordingly, the present disclose provides an apparatus and method for communicating data using an electric field in order to reduce a communication link setup delay. 
     Another aspect of the present disclose is to provide an apparatus and method for controlling a connection between electronic devices through Electric Field Communication (EFC). 
     Yet another aspect of the present disclose is to provide an apparatus and method for searching an electronic device for setting up a communication link through EFC. 
     According to a first aspect of the present disclose, a method for communication link setup in a first electronic device includes: setting up an Electric Field Communication (EFC) link with a second electronic device; determining connection setup information of the second electronic device through the EFC link; and setting up a short range communication link with the second electronic device by using the connection setup information. 
     According to a second aspect of the present disclose, an apparatus for a first electronic device includes: an Electric Field Communication (EFC) unit; a communication unit for short range communication; at least one processor; a memory; and at least one program stored in the memory and executed by the processor, wherein the program includes at least one instruction for setting up an EFC link with a second electronic device and setting up a short range communication link with the second electronic device through the communication unit by using connection setup information of the second electronic device determined through the EFC link. 
     According to a third aspect of the present disclose, an apparatus for a first electronic device includes: an Electric Field Communication (EFC) unit for setting up an EFC link with a second electronic device and determining connection setup information of the second electronic device through the EFC link; and a communication unit for setting up a short range communication link with the second electronic device by using the connection setup information of the second electronic device determined through the EFC unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the present disclose will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a diagram illustrating a configuration of an EFC system according to an exemplary embodiment of the present disclose; 
         FIG. 2  is a diagram illustrating a schematic configuration of an electronic device for EFC according to an exemplary embodiment of the present disclose; 
         FIG. 3  is a diagram illustrating a block configuration of an electronic device for EFC according to an exemplary embodiment of the present disclose; 
         FIG. 4  is a diagram illustrating a process for searching an opponent electronic device through EFC by an electronic device according to an exemplary embodiment of the present disclose; 
         FIG. 5  is a diagram illustrating a process for searching an opponent electronic device through EFC by a Bluetooth electronic device according to an exemplary embodiment of the present disclose; 
         FIG. 6  is a diagram illustrating a process for setting up a communication link in a Bluetooth electronic device according to an exemplary embodiment of the present disclose; 
         FIG. 7  is a diagram illustrating a process for searching an opponent electronic device through EFC by a WLAN electronic device according to an exemplary embodiment of the present disclose; and 
         FIG. 8  is a diagram illustrating a process for setting up a communication link in a WLAN electronic device according to an exemplary embodiment of the present disclose. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Exemplary embodiments of the present disclose will be described herein below with reference to the accompanying drawings. For the purposes of clarity and simplicity, detailed descriptions of well-known functions or configurations will be omitted as they would unnecessarily obscure the subject matters of the present disclose. Also, the terms used herein are defined according to the functions of the present disclose. Thus, the terms may vary depending on users&#39; or operators&#39; intentions or practices. Therefore, the terms used herein should be understood based on the descriptions made herein. 
     Hereinafter, the present disclose describes teachings of controlling a connection between electronic devices through Electric Field Communication (EFC). 
     In the following description, it is assumed that a communication system communicates signals through EFC. Accordingly, the communication system may be configured as illustrated in  FIG. 1   
     In the following description, examples of an electronic device include a mobile terminal, a personal digital assistant (PDA), a laptop computer, a smart phone, a netbook, a television, a mobile internet device (MID), an ultra mobile personal computer (UMPC), a tablet PC, a navigation device, an MP3 player, and any duplex systems. 
       FIG. 1  illustrates a configuration of an EFC system according to an embodiment of the present disclose. 
     As shown  FIG. 1 , the EFC system includes a plurality of electronic devices  100  and a body  110  for EFC. 
     The EFC supports the transmission of signals between electronic devices  101 ,  103  and  105  that are adjacent to the body  110  or are connected to the body  110  by using a low frequency band with near field characteristics as a channel and using the body  110  with conductivity as a communication channel. For example, the first electronic device  101  connected to a user may create an electric field of a predetermined range through the body  110  of the user and communicate signals with the second electronic device  103  or the third electronic device  105  that is located within the electric field. 
     As described above, the EFC is a communication scheme that communicates signals between electronic devices by using a minute electric field created at or around the body  110  of the user. Accordingly, the EFC may establish a signal transmission path through the body connected to the electronic device supporting EFC. 
       FIG. 2  illustrates a schematic configuration of an electronic device for EFC according to an embodiment of the present disclose. 
     As shown in  FIG. 2 , when a first electronic device  201  and a second electronic device  203  communicate signals by using EFC, the first electronic device  201  and the second electronic device  203  communicate signals through an electric field (E-Field) created between the first electronic device  201  and the second electronic device  203 . To this end, the electronic device performing EFC includes an EFC system processing signals communicated through an electric field. 
       FIG. 3  illustrates a block configuration of an electronic device for EFC according to an exemplary embodiment of the present disclose. 
     As shown in  FIG. 3 , an electronic device  300  includes a memory  310 , a processor unit  320 , a communication system  330 , an audio processing unit  340 , an external port  350 , an input/output (I/O) control unit  360 , a display unit  370 , an input device  380 , and an EFC system  390 . Herein, the memory  310 , the communication system  330 , and the external port  350  may be provided in multiples. 
     The memory  310  may include a data storage unit  311  for storing data generated during the execution of a program, and a program storage unit  312  for storing a program for controlling an operation of the electronic device  300 . 
     The program storage unit  312  may include an operation system (OS) program  313 , a communication program  314 , a graphic program  315 , a user interface (UI) program  316 , at least one application program  317 , and an EFC program  318 . Herein, the program included in the program storage unit  312  is a set of instructions and may be referred to an instruction set. 
     The OS program  313  includes at least one software element for controlling a general system operation. Also, the OS program  313  may perform a function for smoothing communication between a plurality of hardware and software elements. 
     The communication program  314  includes at least one software element for processing data communicated through the communication system  330  or the external port  350 . For example, the communication program  314  may include an instruction for performing communication connection with a second electronic device selected through the EFC system  390 . 
     The graphic program  315  includes at least one software element for providing and displaying graphics on the display unit  370 . 
     The UI program  316  includes at least one software element related to a user interface. 
     The application program  317  includes a software element for at least one application program installed in the electronic device  300 . 
     The EFC program  318  includes at least one software element for processing data communicated through the EFC system  390 . For example, the EFC program  318  may include an instruction for selecting an opponent electronic device to set a communication link through the EFC system  390 . 
     The processor unit  320  includes a memory interface  321 , at least one processor  322 , and a peripheral interface  323 . Herein, the memory interface  321 , the processor  322  and the peripheral interface  323  included in the processor unit  320  may be integrated into at least one integrated circuit or may be implemented in separate elements. 
     The memory interface  321  controls the access to the memory  310  by an element such as the processor  322  or the peripheral interface  323 . 
     The peripheral interface  323  controls the connection between the processor  322 , the memory interface  321  and a peripheral I/O device of the electronic device  300 . 
     The processor  322  uses at least one software program to perform control so that the electronic device  300  provides various multimedia services. In this case, the processor  322  executes at least one program stored in the memory  310  and provides a service corresponding to the program. For example, the processor  322  may include one or more data processors, image processors, and output control processors. 
     The communication system  330  performs a communication function for voice communication and data communication of the electronic device  300  through a short range communication scheme. The communication system  330  may be divided into a plurality of communication submodules supporting different communication networks. Examples of the communication networks include, but are not limited to, Wireless Local Area Network (WLAN), Bluetooth Network, Infrared Data Association (IrDA), and Near Field Communication (NFC). 
     The audio processing unit  340  provides an audio interface between a user and the electronic device  300  through a speaker  341  and a microphone  342 . 
     The external port  350  includes a connection interface for connecting the electronic device  300  directly to an external electronic device or connecting the electronic device  300  to any other electronic device through a network. For example, the external port  350  includes a Universal Serial Bus (USB) port, a High-Definition Multimedia Interface (HDMI) port, and a FIREWIRE port. 
     The I/O control unit  360  provides an interface between the peripheral interface  323  and I/O devices such as the display unit  370  and the input device  380 . 
     Under the control of the graphic program  315 , the display unit  370  displays status information of the electronic device  300 , characters input by the user, moving pictures, still pictures, and the like. 
     The input device  380  provides input data generated by user selection to the processor unit  320  through the I/O control unit  360 . In this case, the input device  380  includes a keypad including at least one hardware button, and a touchpad detecting touch information. For example, the input device  380  provides touch information, such as a touch release, a touch motion and a touch detected through a touch pad, to the processor  322  through the I/O control unit  360 . 
     The EFC system  390  performs a communication function for communicating signals through an electric field. For example, the EFC system  390  may include an electrode unit for creating an electric field and a communication system for processing signals communicated through the electric field. 
     Although not illustrated, the electronic device  300  may further include a broadband communication system performing a communication function for voice communication and data communication through a broadband communication network. Examples of the broadband communication network may include a GSM (Global System for Mobile Communication) network, an EDGE (Enhanced Data GSM Environment) network, a CDMA (Code Division Multiple Access) network, a W-CDMA (W-Code Division Multiple Access) network, an LTE (Long Term Evolution) network, and an OFDMA (Orthogonal Frequency Division Multiple Access) network. 
     In the above-described embodiment, the electronic device  300  includes the communication program  314  and the EFC program  318  performing control so that an initial setup for communication link setup through the communication system  330  is performed through the EFC system  390 . 
     In another embodiment, the electronic device  300  may include a separate processor performing control so that an initial setup for communication link setup through the communication system  330  is performed through the EFC system  390 . 
     As described above, the electronic device  300  sets up a communication link with another electronic device selected through the EFC system  390  by using the communication system  330 . In this case, the electronic device  300  operates as illustrated in  FIG. 4 . 
       FIG. 4  illustrates a process for searching another electronic device through EFC by an electronic device according to an embodiment of the present disclose. 
     Referring to  FIG. 4 , in step  401 , the electronic device determines whether to set up a communication link for data communication through a short range communication network. For example, the electronic device determines whether an application program for data communication is executed. As another example, the electronic device may determine whether a service function for data communication is set up. 
     When a communication link for data communication is not set up, the electronic device ends the present algorithm. 
     On the other hand, when a communication link for data communication is set up, the electronic device performs step  403 . In step  403 , the electronic device determines whether an EFC network can be established. For example, the electronic device determines whether a second electronic device for establishing an EFC network is present in the periphery. More particularly, the electronic device determines whether there is a second electronic device for establishing a transmission path through an electric field created through a body of a user. 
     When an EFC network cannot be established due to the absence of an electric field detection, the electronic device performs step  413 . In step  413 , the electronic device performs a general communication link setup process to set up a communication link with the second electronic device for performing data communication. 
     On the other hand, when an EFC network can be established, the electronic device performs step  405 . In step  405 , the electronic device sets up an EFC link with the second electronic device. To achieve this, the electronic device transmits an EFC connection request message to the second electronic device through the EFC network. Thereafter, when the second electronic device accepts the EFC connection setup request, the electronic device sets up an EFC link with the second electronic device. 
     After setting up the EFC link with the second electronic device, the electronic device performs step  407 . In step  407 , the electronic device determines connection setup information for setting up a communication link with the second electronic device through the EFC link. For example, the electronic device exchanges connection setup information with the second electronic device through the EFC link. Here, the connection setup information includes at least one of a Bluetooth address and a Bluetooth profile of the second electronic device. Alternatively, the connection setup information includes Extensible Authentication Protocol (EAP) authentication information. 
     Thereafter, in step  409 , the electronic device sets up a communication link with the second electronic device for short range communication by using the connection setup information. For example, when a Bluetooth scheme is used, the electronic device sets up a Bluetooth communication link with the second electronic device by using Bluetooth connection setup information determined through the EFC link. Alternatively, when a WLAN scheme is used, the electronic device sets up a WLAN communication link with the second electronic device by using WLAN connection setup information determined through the EFC link. 
     After setting up the communication link with the second electronic device, the electronic device performs step  411 . In step  411 , the electronic device communicates data with the second electronic device through the communication link with the second electronic device. 
     Thereafter, the electronic device ends the present algorithm. 
     As described above, the electronic device determines connection setup information for setting up a communication link with the second electronic device through the EFC link. That is, the electronic device performs an initial setup of a communication link corresponding to a communication scheme such as Bluetooth or WLAN by using EFC, thereby reducing a communication link setup delay. The EFC is a communication scheme that uses a body of a user of the electronic device and an electric field created near the body. Accordingly, by recognizing that the second electronic device capable of setting the EFC link is adjacent to the electronic device, without performing a separate scan for communication link setup, the electronic device recognizes that a communication link of another communication scheme can be set up. 
     For example, when the electronic device sets up a communication link with the second electronic device by using a Bluetooth scheme, the electronic device may perform an initial setup for a Bluetooth communication link with the second electronic device by using EFC, as illustrated in  FIG. 5 . 
       FIG. 5  illustrates a process for searching another electronic device through EFC by a Bluetooth electronic device according to an embodiment of the present disclose. 
     Referring to  FIG. 5 , in step  501 , the electronic device determines whether a Bluetooth connection event occurs. For example, the electronic device determines whether an application program for Bluetooth connection is selected. 
     When a Bluetooth connection event does not occur, the electronic device ends the present algorithm. On the other hand, when a Bluetooth connection event occurs, the electronic device performs step  503 . In step  503 , the electronic device determines whether an EFC network can be established. For example, the electronic device determines whether a second electronic device for establishing an EFC network is present in the periphery. That is, the electronic device may determine whether there is a second electronic device for establishing a transmission path through an electric field created through a body of a user. 
     When an EFC network cannot be established, the electronic device performs step  517 . In step  517 , the electronic device performs a general Bluetooth communication link setup process to set up a Bluetooth communication link with the second electronic device. 
     On the other hand, when an EFC network can be established, the electronic device performs step  505 . In step  505 , the electronic device sets up an EFC link with the second electronic device. For example, the electronic device transmits an EFC connection request message to the second electronic device through the EFC network. Thereafter, when the second electronic device accepts the EFC connection setup request, the electronic device sets up an EFC link with the second electronic device. 
     After setting up the EFC link with the second electronic device, the electronic device performs step  507 . In step  507 , the electronic device requests connection setup information for communication link setup from the second electronic device through the EFC link. Herein, the connection setup information includes a Bluetooth profile and a Bluetooth address of the second electronic device. 
     Thereafter, in step  509 , the electronic device determines whether a response message to the connection setup information request is received from the second electronic device through the EFC link. 
     When a response message to the connection setup information request is not received from the second electronic device for a predetermined time, the electronic device recognizes that a Bluetooth communication link with the second electronic device cannot be set up. Accordingly, the electronic device ends the present algorithm. Alternatively, the electronic device may re-request connection setup information from the second electronic device. 
     When a response message to the connection setup information request is received from the second electronic device, the electronic device performs step  511 . In step  511 , the electronic device determines whether to set up a Bluetooth communication link with the second electronic device. For example, the electronic device compares the Bluetooth connection application program generated in step  501  with the Bluetooth profile of the second electronic device to determine whether to set up a Bluetooth communication link with the second electronic device. 
     When a Bluetooth communication link with the second electronic device cannot be set up, the electronic device recognizes that a Bluetooth communication link with the second electronic device cannot be set up. Accordingly, the electronic device ends the present algorithm. 
     On the other hand, when a Bluetooth communication link with the second electronic device can be set up, the electronic device performs step  513 . In step  513 , the electronic device sets up a Bluetooth communication link with the second electronic device by pairing with the second electronic device. 
     After setting up the communication link with the second electronic device, the electronic device performs step  515 . In step  515 , the electronic device communicates data with the second electronic device through the communication link with the second electronic device. 
     Thereafter, the electronic device ends the present algorithm. 
     As described above, the electronic device determines connection setup information for setting up a Bluetooth communication link with the second electronic device through the EFC link. That is, the electronic device performs an initial setup for a Bluetooth communication link for EFC. In this case, the second electronic device setting a Bluetooth communication link with the electronic device operates as illustrated in  FIG. 6 . 
       FIG. 6  illustrates a process for setting up a communication link in a Bluetooth electronic device according to an embodiment of the present disclose. 
     Referring to  FIG. 6 , it is assumed that the second electronic device operates in an idle state in step  601 . 
     Thereafter, in step  603 , the second electronic device determines whether an EFC network can be established. For example, the second electronic device determines whether an electric field for EFC is detected. 
     When an EFC network cannot be established due to the absence of an electric field detection, the second electronic device ends the present algorithm. 
     On the other hand, when an EFC network can be established, the second electronic device performs step  605 . In step  605 , the second electronic device determines whether an EFC connection request message is received from the electronic device creating the electric field. 
     When an EFC connection request message is not received, the second electronic device ends the present algorithm. 
     On the other hand, when an EFC connection request message is received, the second electronic device performs step  607 . In step  607 , the second electronic device sets up an EFC link with the electronic device. For example, when an EFC connection request message is received, the second electronic device determines whether to accept the EFC connection setup request. When accepting the EFC connection setup request of the electronic device, the second electronic device may transmit an EFC connection setup accept message to the electronic device to set up an EFC link with the electronic device. On the other hand, when not accepting the EFC connection setup request of the electronic device, the second electronic device may end the present algorithm. 
     After setting up the EFC link with the electronic device, the second electronic device performs step  609 . In step  609 , the second electronic device determines whether a connection setup information request message is received from the electronic device through the EFC link. 
     When a connection setup information request message is not received for a predetermined time after establishment of the EFC link, the second electronic device ends the present algorithm. 
     On the other hand, when a connection setup information request message is received from the electronic device through the EFC link, the second electronic device performs step  611 . In step  611 , the second electronic device transmits connection setup information to the electronic device through the EFC link. Herein, the connection setup information includes a Bluetooth profile and a Bluetooth address of the second electronic device. 
     Thereafter, in step  613 , the second electronic device sets up a Bluetooth communication link with the electronic device by pairing with the electronic device. 
     After setting up the communication link with the electronic device, the second electronic device performs step  615 . In step  615 , the second electronic device communicates data with the electronic device through the communication link with the electronic device. 
     Thereafter, the second electronic device ends the present algorithm. 
     In the above-described embodiment, the electronic device sets up a Bluetooth communication link with the second electronic device. 
     In another embodiment, the electronic device may set up a WLAN communication link with the second electronic device as illustrated in  FIG. 7 . 
       FIG. 7  illustrates a process for searching an opponent electronic device through EFC by a WLAN electronic device according to an embodiment of the present disclose. 
     Referring to  FIG. 7 , in step  701 , the electronic device searches peripheral APs. 
     Thereafter, in step  703 , the electronic device determines whether an AP supporting a WPS (Wi-Fi Protected Setup) function is present among the peripheral APs. Herein, the AP supporting a WPS function includes a WSC (Wi-Fi Simple Config Specification) IE. 
     When an AP supporting a WPS function is not present among the peripheral APs, the electronic device ends the present algorithm. 
     On the other hand, when an AP supporting a WPS function is present among the peripheral APs, the electronic device performs step  705 . In step  705 , the electronic device determines whether an EFC network can be established. For example, the electronic device determines whether a second electronic device for establishing an EFC network is present in the periphery. That is, the electronic device may determine whether there is a second electronic device for establishing a transmission path through an electric field created through a body of a user. 
     When an EFC network cannot be established, the electronic device performs step  719 . In step  719 , the electronic device performs a general WLAN communication link setup process to set up a WLAN communication link with the second electronic device. 
     On the other hand, when an EFC network can be established, the electronic device performs step  707 . In step  707 , the electronic device sets up an EFC link with the second electronic device. For example, the electronic device transmits an EFC connection request message to the second electronic device through the EFC network. Thereafter, when the second electronic device accepts the EFC connection setup request, the electronic device sets up an EFC link with the second electronic device. 
     After setting up the EFC link with the second electronic device, the electronic device performs step  709 . In step  709 , the electronic device performs an Extensible Authentication Protocol (EAP) authentication process with the second electronic device through the EFC link. 
     Thereafter, in step  711 , the electronic device determines whether the EAP authentication has succeeded. 
     When the EAP authentication has not succeeded, the electronic device recognizes that a WLAN communication link with the second electronic device cannot be set up. Accordingly, the electronic device ends the present algorithm. 
     On the other hand, when the EAP authentication has succeeded, the electronic device performs step  713 . In step  713 , the electronic device attempts to connect with the second electronic device for WLAN communication link setup based on connection information received in the EAP authentication process. Herein, the second electronic device includes an AP or a host electronic device supporting a WLAN direct technology. 
     Thereafter, in step  715 , the electronic device determines whether the connection with the second electronic device has succeeded. 
     When the connection with the second electronic device has failed, the electronic device ends the present algorithm. 
     On the other hand, when the connection with the second electronic device has succeeded, the electronic device performs step  717 . In step  717 , the electronic device communicates data with the second electronic device through the WLAN communication link with the second electronic device. 
     Thereafter, the electronic device ends the present algorithm. 
     As described above, the electronic device performs an initial setup for a WLAN communication link for EFC. In this case, the second electronic device setting a WLAN communication link with the electronic device operates as illustrated in  FIG. 8 . 
       FIG. 8  illustrates a process for setting up a communication link in a WLAN electronic device according to an embodiment of the present disclose. 
     Referring to  FIG. 8 , in step  801 , the second electronic device determines whether an EFC network can be established. For example, the second electronic device determines whether an electric field for EFC is detected. 
     When an EFC network cannot be established due to the absence of an electric field detection, the second electronic device ends the present algorithm. 
     On the other hand, when an EFC network can be established, the second electronic device performs step  803 . In step  803 , the second electronic device determines whether an EFC connection request message is received from the electronic device creating the electric field. 
     When an EFC connection request message is not received, the second electronic device ends the present algorithm. 
     On the other hand, when an EFC connection request message is received, the second electronic device performs step  805 . In step  805 , the second electronic device sets up an EFC link with the electronic device. For example, when an EFC connection request message is received, the second electronic device determines whether to accept the EFC connection setup request. When accepting the EFC connection setup request of the electronic device, the second electronic device may transmit an EFC connection setup accept message to the electronic device to set up an EFC link with the electronic device. On the other hand, when not accepting the EFC connection setup request of the electronic device, the second electronic device may end the present algorithm. 
     After setting up the EFC link with the electronic device, the second electronic device performs step  807 . In step  807 , the second electronic performs EAP authentication of the electronic device through the EFC link. 
     Thereafter, in step  809 , the second electronic device determines whether the EAP-authenticated electronic device requests a connection. 
     When the electronic device does not request a connection for a predetermined time after the EAP authentication, the second electronic device ends the present algorithm. 
     On the other hand, when the EAP-authenticated electronic device requests a connection, the second electronic device performs step  811 . In step  811 , the second electronic device sets up a WLAN communication link with the electronic device. 
     After setting up the communication link with the electronic device, the second electronic device performs step  813 . In step  813 , the second electronic device communicates data with the electronic device through the communication link with the electronic device. 
     Thereafter, the second electronic device ends the present algorithm. 
     As described above, the connection between electronic devices is controlled through EFC, thereby making it possible to reduce a time delay for searching an opponent electronic device to set up a communication link. 
     The above-described methods according to the present disclose can be implemented in hardware, firmware or as software or computer code that can be stored in a recording medium such as a CD ROM, an RAM, a floppy disk, a hard disk, or a magneto-optical disk or computer code downloaded over a network originally stored on a remote recording medium or a non-transitory machine readable medium and to be stored on a local recording medium, so that the methods described herein can be rendered in such software that is stored on the recording medium using a general purpose computer, or a special processor or in programmable or dedicated hardware, such as an ASIC or FPGA. As would be understood in the art, the computer, the processor, microprocessor controller or the programmable hardware include memory components, e.g., RAM, ROM, Flash, etc. that may store or receive software or computer code that when accessed and executed by the computer, processor or hardware implement the processing methods described herein. In addition, it would be recognized that when a general purpose computer accesses code for implementing the processing shown herein, the execution of the code transforms the general purpose computer into a special purpose computer for executing the processing shown herein. 
     While the disclose has been shown and described with reference to certain exemplary 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 disclose as defined by the appended claims. Therefore, the scope of the disclose is defined not by the detailed description of the disclose but by the appended claims, and all differences within the scope will be construed as being included in the present disclose.