KR20110001843A - Method of switching coordinator point in body area network - Google Patents

Abstract

PURPOSE: A method of switching a coordinator point in a body area network is provided to replace a CP(Coordinator Point) by adopting the performance of another wireless communication device in real time. CONSTITUTION: A candidate CP transmits a CP switch request message to a primary CP(S410), and the primary CP transmits a CP switch response message to the candidate CP(S420). The candidate CP is in a standby state for a limit time(S430). The candidate CP transmits to body area network devices the CP switch announcement message for informing the role of the CP function(S440). The candidate CP performs the CP function of the CP with the primary CP or performs CP role as sub CP.

Description

How to change the CPU in JAN {METHOD OF SWITCHING COORDINATOR POINT IN BODY AREA NETWORK}

The present invention relates to a wireless communication system, and more particularly, to a Coordinator Point (CP) in a body area network.

There is a growing interest in integrating information and communication technology into medical services around the world. These technologies include the process of measuring, transmitting, analyzing, and feeding back personal biosignal and medical information, which are being actively researched around the world, and the IEEE 802.15 WPAN Standardization Committee has established a medical wireless medical wireless network (BAN). A study group (BAN (Body Area Network)) was formed, and last year, TG (Task group) 6 was established under IEEE 802.15, and BAN is being standardized.

In addition, the frequency of 402 ~ 405MHz is used for medical use all over the world, and the research is actively conducted since the ISM (Industrial, Scientific and Medical) band and the UWB (Ultra Wide-Band) band can be used for the transmission of biological signals. It is becoming.

Body Area Network (BAN) is a communication network that occurs mainly in the vicinity of a human body. More specifically, it refers to communication and networks between devices in-body, on-body, and off-body. You can think of medical applications, but more diverse applications are possible. Since the technology developed in connection with BAN is not limited to the human body but also applied to an organism having an environment similar to that of an animal or other human being, the application field may become more diverse.

The human body is a radio communication environment that is somewhat different from a personal area network (PAN). Because PAN solves the problem of communication between devices on-body and other devices over 10 meters away, transmission through the body is not the primary target transmission environment, and also interferes with the body's radio transmission environment. Factors do not matter too much.

In contrast, BAN makes a difference in that the body makes itself the main environment for radio wave transmission. In addition, there may be various modes of communication of the BAN. In other words, there are various types of communication modes between devices in the body, devices in the body and devices on the body, devices on the body, devices on the body and devices near the body.

Considering these special propagation environments and various communication modes, there may be insufficient aspects of Bluetooth or ZigBee, which were previously developed as PANs, to be used as BANs, so signal transmission technology needs to be developed. Is recognized.

If we classify the BAN technology discussed so far, it can be classified into medical BAN (non-medical BAN) and non-medical BAN (Non-medical BAN) technology by application field, and from the human body surface to the coordinator by channel. It can be classified into communication, communication between the human body surface, communication between the human body and the human body surface, and communication within the human body. In addition, the media used may be classified into a method of using a radio, a method of using a wire, and a method of using a human body as a medium. It can be classified according to whether the built-in power supply exchanges only data, supplies power externally, or generates power within itself. The medical BAN may be classified into a wearable BAN, which is a network between nodes attached to the body, and an implant BAN, which is a network between implantable nodes implanted in the human body.

BAN supports low cost, low complexity, ultra-low power, and highly reliable wireless communication inside and outside the body. BAN also supports medical and non-medical applications.

In the case of a medical / healthcare application, a low data rate and ultra-low power of 10 Kbps or less are used. In addition, non-medical applications have a feature of using a high data rate and low power of 10Mbps or more.

As such, in BAN, various applications are supported and a network related to a human body may cause various situations according to each application. It is difficult to rule out the possibility of an emergency, especially in medical / healthcare applications. Therefore, in such a case, the development of technology to complement the function of the CP and to promote the stability of the system is required.

According to an embodiment of the present invention, when a CP failure occurs in a body area network (BAN), it is intended to provide a method for quickly solving this. In addition, to provide a method for detecting the failure of the CP, and to replace the CP to reflect the performance of the other wireless communication device in real time, to provide a method for adaptively coping with the failure of the CP. In particular, due to the nature of the BAN, there is a need for a technology for quickly resolving data or a situation sensitive to delay or loss by using another wireless communication device to replace the CP, rather than waiting for the CP to recover in case of an emergency or emergency.

According to an aspect of the present invention, in a method of changing a coordinator point (CP) in a body area network (BAN), transmitting a CP switch request message to a primary CP; Receiving a CP switch response message including CP change timeout information from a CP, CP change notification message if the data from the main CP is not received within the time limit according to the CP change timeout information Provided is a method of changing a CP in a BAN including transmitting a CP Switch Announcement Message to a DEV.

According to another aspect of the present invention, a wireless communication device for changing a CP in the BAN, the processor for generating a CP change request message and further generates a CP change notification message when detecting the failure of the main CP and the CP change request message Is transmitted to the main CP, receives a CP change response message from the main CP, and when the processor detects the failure of the main CP to change the CP in the BAN including an RF unit for transmitting the CP change notification message to another DEV A wireless communication device is provided.

When a CP failure occurs in a body area network (BAN), it can be quickly resolved. A standard for detecting a failure of a CP may be provided, and the CP may be replaced in real time to reflect the performance of another wireless communication device, thereby adaptively coping with the failure of the CP. In particular, due to the characteristics of the BAN, in case of an emergency or an emergency situation, by using another wireless communication device serving as a CP rather than waiting for the CP to be recovered, a problem that may occur when transmitting data sensitive to delay or loss can be solved quickly. Therefore, service stability and data transmission reliability may be improved in BAN communication.

1 is a diagram illustrating a system configuration of a BAN.

The BAN system may include a device acting as a central point (CP) 100 and the remaining terminal (s). In the BAN system, the terminal other than the CP may be simply displayed as body area network devices (DEVs) 110 and 120, and may perform a function of measuring or receiving a biosignal and delivering the signal to the CP 100. In addition, a portable terminal, a mobile communication terminal, a personal digital assistant (PDA), and the like may serve as the CP 100, and a biosignal collecting device, a biosignal measuring device, and a biosignal monitoring device may serve as the DEVs 110 and 120. can do.

The CP 100 serves as a coordinator in the BAN system from the DEVs 110 and 120, receives various signals transmitted through the BAN, processes the signals, stores them, and stores them therein. You can output In addition, the data transmission cycle or resource allocation of the various DEVs 110 and 120 may be controlled.

2 is a diagram illustrating a frame structure according to the IEEE 802.15.3 standard. IEEE 802.15.3 is a protocol for high rate wireless personal area network (WPAN).

The overall time may include several superframes, which are described as an example of the superframe #m 200, which is an arbitrary superframe. The super frame includes a beacon 210, a contention access period (CAP) 220, and a contention free period (CFP), and data transmission mainly occurs in the CFP period. The CFP period is indicated by a channel time allocation period (CTAP) 230. In the high speed WPAN according to IEEE 802.15.3, since there is no requirement for low power, an inactivity period is not defined separately.

The beacon frame 210 is used to transmit control information to the DEVs, allocate radio resources in the current super frame (super frame #m, 200), and synchronize time.

Contention access period 220 is used for authentication, connection request, connection response, data stream parameter negotiation, and the like. The CAP 220 uses a carrier sense multiple access / collision avoidance (CSMA / CA) mechanism for medium access.

Channel time allocation period (CTAP) 230 is composed of one or more channel time allocations (CTAs) 231, 232, ..., 239. It may include a management CTA. CTAs 231, 232, ..., 239 are used for instruction streams, concurrent streams, and asynchronous or asynchronous data connections. CTAP 230 may use a time division multiple access (TDMA) protocol when the DEVs have a specified time window.

3 is a diagram illustrating a frame structure according to the IEEE 802.15.4 standard. IEEE 802.15.4 is a protocol for low rate wireless personal area network (WPAN). In IEEE 802.15.4, a GTS (Guaranteed Time Slot) 321 is allocated for each DEV.

The super frame is defined by the beacon 305 transmitted by the CP, and can be divided into 16 equally sized slots. Any DEV that wishes to communicate during the competitive access cycle (CAP) 310 will compete with another DEV using the CSMA / CA mechanism.

The superframe is divided into a certain period of activity cycle and inactivity cycle 330. The activity cycle includes a competitive access cycle (CAP) 310 and a non-competitive cycle (CFP) 320. In the low speed WPAN of IEEE 802.15.4, an active period and an inactive period 330 are divided into a predetermined ratio. The ratio of active cycle to inactive cycle 330 is referred to as duty cycle. While the CP is in an inactive cycle, the CP enters a low power mode.

That is, the activity cycle includes a beacon 305, CAP 310, CFP 320, data transmission mainly occurs in the CFP (320) section. For applications where transmission delay is an issue or for applications that require a specific data bandwidth, the CP can adjust the rate of activity periods in the super frame for that application. A guaranteed time slot (GTS) 321 means an activity cycle allocated in this way. The GTS 321 constitutes a non-competition period (CFP) 320.

4 is a flowchart illustrating a CP change method according to an embodiment of the present invention.

The candidate CP transmits a CP switch request message to a primary CP (S410). The candidate CP means a DEV capable of performing the role of CP among the DEVs. In an embodiment of the present invention, the candidate CP may be two or more. The CP change request message may be that the candidate CP actively requests a change of the CP to perform the role of the CP, or may indicate that it is possible to simply perform the role of the CP. In the latter case, the candidate CP may play the role of the CP by the judgment or necessity of the main CP rather than the candidate CP.

The main CP transmits a CP switch response message to the candidate CP in response to the CP change request message of the candidate CP (S420). The CP change response message includes information on a time limit for allowing the candidate CP to determine that the main CP has failed when the main CP does not transmit any frame within a predetermined time.

That is, if the candidate CP does not receive any signal or data from the main CP within the time limit included in the CP change response message, the candidate CP may determine that the main CP has failed. In this case, the candidate CP can play the role of the CP thereafter. The candidate CP that has performed the role of the CP may be referred to as a secondary CP. When the candidate CP plays the role of the CP as the secondary CP, the secondary CP may be performed together with the existing main CP or alternatively to the existing main CP to perform the role of the CP alone.

Therefore, the candidate CP waits until the time limit elapses from receiving the CP switch response message or before the frame is received from the main CP (S430). If a frame such as a signal or data is received from the main CP within the time limit, the candidate CP determines that the main CP operates normally, and does not need to change the CP or perform a role of the CP. Of course, there is no need to send a CP change notification message. However, when waiting for a time limit but nothing is received from the main CP, the candidate CP detects a failure as described above, and proceeds with the procedure for changing the CP.

The candidate CP, which has performed the role of the CP through the above-described process, is a secondary CP, and notifies the primary CP, which is not the existing primary CP, to function as a CP, or to the existing primary CP. In addition, a CP switch announcement message is transmitted to DEVs to inform that the corresponding candidate CP has been added as a device serving as a CP (S440). If the CP is changed, the candidate CP becomes the secondary CP, and instead of the main CP, the secondary CP plays a role as a CP, or the secondary CP plays a role as a CP together with the main CP. The CP change notification message may be transmitted by a multicast or broadcast method, and thus may also be received by an existing main CP.

In addition, when the secondary CP, which has played the role of the CP after the transmission of the CP change notification message, intends to stop performing the role of the CP, the secondary CP may transmit the CP change stop request message again. The step of transmitting the CP change stop request message is not shown in FIG. 4. In this case, the primary CP may respond to the request of the secondary CP by sending a CP change abort response message. In addition, the main CP or the sub-CP retransmits the CP change notification message to other DEVs, or sends a CP change stop notification message, indicating that the device acting as a CP has been changed to one of the existing main CP or another candidate CP. You will be notified.

5 is a diagram illustrating an example of a CP switch request message transmitted according to an embodiment of the present invention. 6 is a diagram illustrating an example of a CP switch response message transmitted according to an embodiment of the present invention.

The CP change request message may use the format of a CP Switch Request management frame, and the CP change response message may use the format of a CP Switch Response management frame. The CP change request management frame may include a category field 510, an action field 520, a dialog token field 530, a CP change code field 540, and a performance information field 550. In addition, the CP change response management frame includes a category field 610, an action field 620, a dialog token field 630, a CP change code field 640, a status code field 650, and a CP change timeout field 660. It may include.

The category fields 510 and 610 and the action fields 520 and 620 commonly included in the CP change request management frame and the CP change response management frame specify a category or a function of the corresponding frame. The category fields 510 and 610 may indicate, for example, a category such that the corresponding frame is not a data but a management frame or a management frame related to a change of a CP. The action fields 520 and 620 may indicate that the frames are intended to function to request or respond to a change of the CP. Also, the dialog token fields 530 and 630 are used as a transaction ID value between CP change request / CP switch response management frames.

In addition, the CP switch code field 540 in the CP change request management frame has a value corresponding to Active / Inactive. If a DEV becomes a candidate CP and wants to play a role of a CP, the CP change code is set to an active value. In addition, when the candidate CP wants to quit the role as a CP in the CP change response management frame, the candidate CP may transmit a CP change request management frame in which the CP switch code is set to inactive. That is, the CP change code field 540 includes information indicating whether the candidate CP plays the role of the CP or stops performing the CP role.

In the CP change request management frame, a capability information field 550 indicates information on capabilities that a corresponding candidate CP can support in performing a role as a CP. Information included in the performance information field 550 may be referred to as CP performance information. For example, CP capability information may refer to a power supply situation of the corresponding candidate CP. That is, in this case, CP capability information (CP Capability Information) indicates whether sufficient power is secured to the candidate CP to serve as a CP. If the candidate CP is a battery operated device powered by a battery, the performance information is the battery value, and if the candidate CP is the main powered device, the performance information is the main power value. Can be represented.

In the CP change response message, the information included in the CP change code field 640 of the CP change response management frame is the same as the CP change code requested by the candidate CP.

The status code field 650 has a value corresponding to Accept / Deny for the CP change code field 540 requested in the CP change request management frame.

There are two kinds of procedures for a candidate CP to start or stop performing a role as a CP. One is that the CP change is performed by the candidate CP transmitting the CP change request management frame to the main CP, and the main CP transmitting the CP change response management frame to the candidate CP. The other is that the main CP forcibly controls the change of the CP. That is, even if the main CP does not receive the CP change request management frame from the candidate CP, the CP change response management frame may be transmitted to the candidate CP. In this case, the CP change response management frame transmitted by the primary CP to the candidate CP or the secondary CP includes an instruction to start or stop performing the CP role.

This will be described with reference to the CP change code field 540 of the CP change request management frame, the CP change code field 640 and the status code field 650 of the CP change response management frame as follows.

First of all, the candidate CP transmits a CP change request management frame to the main CP in order to play a role of the CP. In this case, the candidate CP sets the field value of the CP change code field 540 of the CP change request management frame to ACTIVE and transmits the CP change request management frame to the main CP. The CP change code field 640 of the CP change response management frame, which is transmitted in response to the CP change request management frame in which the field value of the CP change code field 540 is set to ACTIVE, is the CP change code field of the CP change request management frame. It is set equally to ACTIVE according to the field value of 540. In addition, if the request content of the CP change request management frame is accepted, the status code field 650 of the CP change response management frame is set to ACCEPT, and if it is not accepted, the DENY is set to DENY. Therefore, in this case, the status code field 650 of the CP change response management frame is set to ACCEPT.

When the sub-CP, which was acting as a CP, transmits the CP change request management frame to stop performing the CP role, the sub-CP may transmit the CP change request management frame in which the CP change code field 540 is set to INACTIVE to the main CP. have. Then, in response to this, the CP change code field 640 of the CP change response management frame transmitted by the primary CP to the secondary CP is set to INACTIVE according to the field value of the CP change code field 540 of the CP change request management frame. do. Therefore, even in this case, the status code field 650 of the CP change response management frame is set to ACCEPT.

That is, when the CP change procedure is performed by the request of the candidate CP or the secondary CP and the positive response of the primary CP, the CP change response management frame may be configured according to the value of the CP change code field 540 of the CP change request management frame. The field value of the CP change code field 640 is set to ACTIVE or INACTIVE. If the main CP does not want to accept the request of the candidate CP or DEV, the field value of the CP change code field 640 of the CP change response management frame with the same value as the CP change code field 540 of the CP change request management frame. Setting the status code field 650 to DENY may indicate rejection of the CP change request.

Then, the following describes how the status code field 650 value of the CP change response management frame transmitted when the primary CP independently performs or forcibly controls the CP change procedure without a request of the candidate CP or the secondary CP is described. Do it.

A DEV or candidate CP that has been reported to have the capability to play the role of a CP but has not requested to function as a secondary CP, has a CP change code field 640 set to ACTIVE and a status code field 650 set to ACCEPT. The change response management frame may be transmitted. That is, in this case, the CP change response management frame transmitted with the status code field 650 set to ACCEPT may be understood as the main CP giving a CP role execution command to the candidate CP or DEV.

Accordingly, the corresponding DEV or candidate CP plays the role of CP as a secondary CP. Since the CP change response management frame is not transmitted in response to the CP change request management frame, it may be referred to as a name other than the CP change response management frame. However, the name does not affect the scope of the present invention.

On the contrary, if the secondary CP, which was playing the role of CP, does not want to perform the CP role anymore, or if it tries to forcibly suppress the CP role in response to unnecessary or inappropriate CP role, the main CP gives the CP. The CP change response management frame in which the change code field 640 is set to INACTIVE and the status code field 650 is set to ACCEPT is transmitted. In this case, the CP change response management frame in which the CP change code field 640 and the status code field 650 are set as described above may be understood as a command for the main CP to stop the CP from serving as a CP.

In the above-described example, the name or value of the CP change code field 540 of the CP change request management frame, the CP change code field 640 or the status code field 650 of the CP change response management frame may be used for explanation and understanding. It is merely an example for the sake of clarity, and thus the scope of the invention is not limited or affected.

In the CP Switch Response management frame of FIG. 6, the CP Switch Timeout field 660 is used to enable a candidate CP to detect CP Failure of the main CP. Indicates the timeout value.

That is, the timeout value shown in the CP change timeout field 660 may be understood as a time limit. The timeout here is that if the candidate CP receives a CP change response message from the main CP and does not receive any other frame within that time limit, the candidate CP may determine that a failure has occurred in the main CP. it means. Accordingly, if the candidate CP receives no frame from the main CP during the time limit according to the CP change timeout field 660 from the main CP, the candidate CP determines that this is a failure for the main CP, so that other DEVs fail the main CP. And / or inform the CP change.

7 is a diagram illustrating an example of a CP change notification message transmitted according to an embodiment of the present invention. The CP change notification message may include a CP switch announcement information element. 7 shows the format of the CP change notification information element.

The CP Switch Announcement Information element is transmitted from the candidate CP to the other DEVs to perform the role of the CP. In this case, a candidate CP that is supposed to play a role of CP is referred to as a secondary CP. The CP change notification information element may be transmitted by being included in a beacon frame by the secondary CP or may be transmitted in a separate message such as a CP change notification message. The secondary CP informs the DEV and the main CP of the CP change (CP Switch) by sending a CP change notification message.

The element ID field 710 serves as an identifier for identifying that the element is related to CP change, and the length field 720 indicates the length of the element.

The primary CP address field 730 includes address information of the primary CP which failed to perform the CP role. The address information of the main CP may include information indicating that the CP is changed or added by specifying the failed main CP, or that the previous main CP may no longer function as the CP. It may include.

The Group Transient Key field 740 corresponds to the value of the shared security key managed in connection with the DEVs connected when the failed main CP plays the role of the CP. When a group is multicasted or broadcasted, the transmission group cipher can limit the participation of other DEVs even if a DEV that is not in the transmission group receives the frame.

In addition, the secondary CP may include its own address information in the CP change notification message. Information on when the secondary CP will play the role of the CP may be included in the CP change notification message, and if the secondary CP's role is restricted by conditions other than the time, The information may also be included in the CP change notification message.

8 is a diagram illustrating a wireless communication apparatus for performing a method of changing a CP in a BAN according to an embodiment of the present invention. The wireless communication apparatus described with reference to FIG. 8 corresponds to a secondary CP among candidate CPs in the CP change method in the BAN according to the embodiment of the present invention described above.

The BAN according to the technical field to which the present invention belongs may support various types of applications. In addition, various applications such as medical and non-medical can be applied to the BAN. Therefore, various situations may occur according to each application, for example, an emergency situation may also occur. The CP may support various applications or one application.

In addition, the device operating as a CP may not be permanently determined, and according to the performance of each DEV, one or more of the DEVs may play the role of the CP. DEV also receives transmission power control information from a Coordinator Point (CP) in such a BAN, and thus serves to transmit emergency data and / or non-emergency data. The terminal may be a biometric device, a biosignal receiving device, or the like.

The BAN wireless communication device includes a processor 810 and an RF unit 820. The RF unit 820 transmits and receives a radio signal, and the processor 810 generates a radio signal or generates control information according to an embodiment of the present invention.

The memory 830 is connected to the processor 810 and stores various information for driving the processor 810. The memory 830 may include read-only memory (ROM), random access memory (RAM), flash memory, memory card, storage medium, and / or other storage device. In addition, the wireless communication device may further include a display unit or a user interface, but is not illustrated in the drawings, and detailed description thereof will be omitted.

The processor 810 may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and / or a data processing device. The processor 810 generates data or control signals to be transmitted to other terminals. That is, the processor 810 generates a CP change request message that is transmitted according to an embodiment of the present invention, and receives a frame from the CP within a time limit according to the CP change response message received in response thereto. Detect If a CP failure is detected, a CP change notification message is generated.

The RF unit 820 is connected to the processor 810, transmits radio signals generated by the processor 810, and receives a radio signal sent by another radio communication device. The RF unit 820 may include a baseband circuit for processing a wireless signal. The BAN wireless communication device transmits a CP change request message to the CP through the RF unit 820 and receives a CP change response message from the CP. When CP failure is detected by the processor 810, the CP change notification message may be transmitted to other DEVs. Since the CP change request message, the CP change response message, the CP change notification message, and their transmission methods have already been described, a repeated description thereof will be omitted.

After transmitting the CP change notification message, the processor 810 and the RF unit 820 perform a function as a CP, and performs communication according to the existing CP and other DEVs and BANs.

All the above-described methods may be performed by a processor such as a microprocessor, a controller, a microcontroller, an application specific integrated circuit (ASIC), or the like according to software or program code coded to perform the method, or a processor of a terminal shown in FIG. 3. have. The design, development and implementation of the code will be apparent to those skilled in the art based on the description of the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention. You will understand. Therefore, the present invention is not limited to the above-described embodiment, and the present invention will include all embodiments within the scope of the following claims.

1 is a diagram illustrating a system configuration of a BAN.

2 is a diagram illustrating a frame structure according to the IEEE 802.15.3 standard.

3 is a diagram illustrating a frame structure according to the IEEE 802.15.4 standard.

4 is a flowchart illustrating a CP change method according to an embodiment of the present invention.

5 is a diagram illustrating an example of a CP switch request message transmitted according to an embodiment of the present invention.

6 is a diagram illustrating an example of a CP switch response message transmitted according to an embodiment of the present invention.

7 is a diagram illustrating an example of a CP change notification message transmitted according to an embodiment of the present invention.

8 is a diagram illustrating a wireless communication apparatus for performing a method of changing a CP in a BAN according to an embodiment of the present invention.

Claims (14)

In the method of changing a Coordinator Point (CP) in a body area network (BAN), Transmitting a CP switch request message to a primary CP; Receiving a CP switch response message including CP change timeout information from the main CP; And transmitting a CP Switch Announcement Message to the DEV when there is no signal received from the main CP within the time limit according to the CP change timeout information. The method of claim 1, The CP change request message includes CP capability information, and the CP capability information is information indicating that a candidate CP corresponding to the CP change request message can serve as a CP. How to change CP in BAN. The method of claim 1, The CP change request message includes information indicating whether or not the candidate CP corresponding to the CP change request message to play the role of CP. The method of claim 1, If the candidate CP corresponding to the CP change request message becomes a sub-CP and performs the role of CP and stops performing the role of the CP, transmitting a CP change stop request message to the main CP further comprising: How to change CP. The method of claim 1, The CP change response message includes information indicating whether to continue performing the function as a CP, CP change method in a BAN. The method of claim 1, The CP change notification message includes information indicating that a candidate CP transmitting the CP change request message becomes a sub-CP and replaces the main CP or plays a role as a CP together with the main CP. How to change CP. The method of claim 1, Wherein the CP change notification message includes address information of the main CP. The method of claim 1, The CP change notification message includes a transmission group cipher that allows a DEV that receives the CP change notification message to participate in a transmission group including the candidate CP that has transmitted the CP change notification message. How to change CP. The method of claim 1, The CP change notification message includes information about the time when the candidate CP plays the role of CP. The method of claim 1, And the CP change notification message includes address information of the candidate CP. In the wireless communication device for changing the CP in the BAN, A processor for generating a CP change request message and further generating a CP change notification message when detecting a failure of the main CP; And And an RF unit for transmitting the CP change request message to the main CP, receiving a CP change response message from the main CP, and transmitting the CP change notification message to another DEV when the processor detects a failure of the main CP. Wireless communication device for changing the CP in the BAN. The method of claim 11, The CP change response message includes time-out information for the processor to detect the failure of the main CP, and if the processor does not receive a frame received through the RF unit from the main CP within the time-out, The wireless communication device for changing the CP in the BAN characterized in that it determines that the failure. The method of claim 11, And the CP change request message includes performance information indicating whether a candidate CP transmitting the CP change request message can function as a CP. The method of claim 12, The CP change notification message includes one or more of the address information of the main CP and a transmission group cipher for joining a transmission group managed by the candidate CP when the candidate CP transmitting the CP change notification message serves as a CP. Wireless communication device for changing the CP in the BAN, characterized in that.

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