WO2019009686A1

WO2019009686A1 - Method and apparatus for discovering device by using bluetooth low energy technology

Info

Publication number: WO2019009686A1
Application number: PCT/KR2018/007757
Authority: WO
Inventors: 백종현; 이민수
Original assignee: 엘지전자 주식회사
Priority date: 2017-07-07
Filing date: 2018-07-09
Publication date: 2019-01-10

Abstract

The present invention relates to a method and an apparatus for discovering a neighboring device by using Bluetooth low energy (LE). In particular, a method performed by a second device may comprise the steps of: receiving, from a first device, a write request message which instructs a change in an advertising channel map and a scanning channel map, wherein the write request message includes an advertisement channel map characteristic and a scanning channel map characteristic; transmitting a write response message to the first device in response to the write request message; transmitting, to a controller of the second device by a host of the second device, a host controller interface (HCI) command which instructs the controller of the second device to change the advertisement channel map on the basis of the advertisement channel map characteristic; and transmitting, to the first device by the controller of the second device, an advertising message by using the changed advertisement channel map.

Description

Method and apparatus for discovering devices using Bluetooth low power energy technology

The present invention relates to a method and apparatus for searching for a device using Bluetooth as a short-range technology in a wireless communication system, and more particularly, to a method and apparatus for searching for an advertisement channel used for device search using Bluetooth low energy (BLE) The present invention relates to a method and an apparatus for protecting a user.

Bluetooth is a short-range wireless technology standard that allows data to be exchanged by wirelessly connecting various devices at a short distance. In order to perform wireless communication between two devices using Bluetooth communication, the user performs a procedure of searching for Bluetooth devices to be communicated and requesting a connection do. In the present invention, a device may mean a device or an apparatus.

At this time, the user can search for the Bluetooth device according to the Bluetooth communication method to be used by using the Bluetooth device, and then perform the connection.

Bluetooth communication methods include BR / EDR (Basic Rate / Enhanced Data Rate) and LE (Low Energy). The BR / EDR scheme may be referred to as Bluetooth Classic. The Bluetooth classical method includes a Bluetooth technology using Bluetooth Basic 1.0 and a Bluetooth technology using an Enhanced Data Rate supported from Bluetooth 2.0.

Bluetooth low energy (hereinafter referred to as Bluetooth LE) technology has been applied since Bluetooth 4.0, and can consume less power and reliably provide information of several hundred kilobytes (KB). These Bluetooth low-power energy technologies use the Attribute Protocol to exchange information between devices. This Bluetooth LE scheme can reduce energy overhead by reducing header overhead and simplifying operation.

Some Bluetooth devices do not have a display or a user interface. The complexity of connection / management / control / disconnection between various types of Bluetooth devices and Bluetooth devices with similar technologies is increasing.

In addition, Bluetooth can be relatively fast at relatively low power and low cost, but the transmission distance is limited to a maximum of 100 m, which is suitable for use in a limited space.

In the current BLE technology, it is impossible to advertise on a channel other than the basic advertisement channel set. Therefore, a new link layer protocol and a new host controller interface (HCI) are required to carry out advertisement using four advertisement channels.

In the case where an advertisement channel set needs to be changed according to the presence or absence of interference, it is necessary to share relevant information between an advertiser and a scanner. However, in the case of using an advertisement PDU defined in the existing BLE technology There is a problem that the above-described technique can not be implemented.

Accordingly, an object of the present invention is to propose a link layer protocol and a host controller interface to solve such a problem and to avoid interference occurring at the band boundary.

The technical objects to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical subjects which are not mentioned are to be clearly understood by those skilled in the art to which the present invention belongs It will be possible.

According to one aspect of the present invention, there is provided a method for discovery of an adjacent device in a wireless communication system using Bluetooth LE (Low Energy), the method being performed in a second device, an advertising channel map and a scanning channel map, the write request message including an advertisement channel map characteristic and a scanning channel map characteristic; Transmitting a write response message to the first device in response to the write request message; The host of the second device transmits a host controller interface (HCI) command for instructing the controller of the second device to change the advertisement channel map based on the advertisement channel map characteristic step; And a controller of the second device transmitting an advertisement message to the first device using the changed advertisement channel map.

Preferably, the advertisement channel map characteristic includes at least one of index information of an available advertisement channel or advertisement channel information included in the advertisement channel map, and the scanning channel map characteristic includes at least one of an available scanning channel Index information or the number of scanning channels included in the scanning channel map.

Preferably, the advertisement channel map may be modified to include at least one advertisement channel in addition to the existing advertisement channel map including three advertisement channels.

Preferably, the host of the second device transmits an HCI command instructing the controller of the second device to change the scanning channel map based on the scanning channel map characteristic.

Advantageously, the scanning channel map may be modified to additionally include at least one scanning channel in addition to the existing scanning channel map including three advertisement channels.

According to another aspect of the present invention, there is provided a second device for discovery of an adjacent device in a wireless communication system using Bluetooth LE (Low Energy), comprising: a communication unit for wirelessly or wiredly communicating with an external device; And a processor operatively connected to the communication unit, wherein the processor receives a write request message for instructing a change of an advertising channel map and a scanning channel map from the first device, The write request message including an advertisement channel map characteristic and a scanning channel map characteristic; Sending a write response message to the first device in response to the write request message; The host of the second device transmits a host controller interface (HCI) command for instructing the controller of the second device to change the advertisement channel map based on the advertisement channel map characteristic ; And the controller of the second device may transmit an advertising message to the first device using the modified advertisement channel map.

Preferably, the host of the second device may transmit an HCI command instructing the controller of the second device to change the scanning channel map based on the scanning channel map characteristic.

According to an exemplary embodiment of the present invention, additional advertisement channels are additionally included in the basic advertisement channel set used in the existing BLE technology, thereby preventing ad / scanning efficiency degradation despite the presence of interference occurring at the boundary of the BLE frequency band BLE device discovery reliability can be increased.

The effects obtainable in the present specification are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description will be.

1 is a schematic diagram illustrating an example of a wireless communication system that utilizes the Bluetooth low power energy technology proposed herein.

Figure 2 shows an example of an internal block diagram of a device capable of implementing the methods proposed herein.

Figure 3 shows an example of a Bluetooth low power energy topology.

4 is a diagram illustrating an example of a Bluetooth communication architecture to which the methods proposed herein can be applied.

5 is a diagram illustrating an example of a structure of a GATT (Generic Attribute Profile) of Bluetooth low-power energy.

6 is a flowchart showing a method of forming a connection using Bluetooth LE (Low Energy) between devices.

FIG. 7 is a diagram for explaining a frequency band of a BLE advertisement channel, to which the present invention can be applied.

8 is a diagram for explaining a frequency band of an advertisement channel, to which the present invention can be applied.

9 is a diagram showing an example of an attribute of a Generic Attribute Profile (GATT) according to an embodiment of the present invention.

10 is a diagram illustrating an example of a characteristic of a GATT (Generic Attribute Profile) according to an embodiment of the present invention.

11 is a diagram illustrating a control message format of a host controller interface according to an embodiment of the present invention.

12 is a diagram illustrating a control message format of a host controller interface according to an embodiment of the present invention.

FIG. 13 is a flowchart illustrating a method of changing a set of advertisement channels based on a GATT (Generic Attribute Profile) according to an embodiment of the present invention.

FIG. 14 is a diagram showing an example of a method for protecting an advertisement channel, to which the present invention can be applied.

The above objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. It is to be understood, however, that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and similarities. Like reference numerals designate like elements throughout the specification. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, a method and an apparatus according to the present invention will be described in detail with reference to the drawings. The suffix " module " and " part " for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role.

The wireless communication system 100 includes at least one server device 120 and at least one client device 110.

The server device and the client device perform Bluetooth communication using Bluetooth low energy (BLE) technology.

First, the BLE technology has a relatively small duty cycle and can be manufactured at a low price compared with the Bluetooth BR / EDR (Basic Rate / Enhanced Data Rate) technology. Since the data rate is low, When using a coin cell battery, it can operate for more than one year.

In addition, BLE technology simplifies the connection procedure between devices, and packet size is designed smaller than Bluetooth BR / EDR technology.

In BLE technology, (1) the number of RF channels is 40, (2) the data rate is 1Mbps, (3) the topology is a scatternet structure, (4) the latency is 3ms, (5) Is less than 15mA, (6) the output power is less than 10mW (10dBm), and (7) it is mainly used in applications such as mobile phones, watches, sports, health care, sensors and device control.

The server device 120 may operate as a client device in relation to another device, and the client device may operate as a server device in relation to another device. That is, in the BLE communication system, any one of the apparatuses can operate as a server apparatus or a client apparatus, and if necessary, can operate simultaneously with the server apparatus and the client apparatus.

The server device 120 includes a data service device, a slave device device, a slave device, a server, a conductor, a host device, a gateway, A monitoring device, a first device, and the like. The client device 110 may include a master device, a master, a client, a member, a sensor device, A sink device, a collector, a second device, a third device, or the like.

The server device and the client device correspond to the main components of the wireless communication system, and the wireless communication system may include other components besides the server device and the client device.

The server device is a device that receives data from a client device, communicates directly with the client device, and provides data to the client device through a response when receiving a data request from the client device.

In addition, the server apparatus sends a Notification message and an Indication message to the client apparatus to provide data information to the client apparatus. In addition, when transmitting an instruction message to the client apparatus, the server apparatus receives a confirmation message corresponding to the instruction message from the client.

In addition, the server device may provide data information to a user through an output unit in a process of transmitting / receiving notifications, instructions, and confirmation messages to / from a client device, or may receive a request input from a user through an input unit (User Input Interface) can do.

In addition, the server apparatus can read data from a memory unit or write new data into a corresponding memory in a process of transmitting and receiving a message with the client apparatus.

In addition, one server device can be connected to a plurality of client devices, and can easily reconnect (or connect) with client devices using bonding information.

The client device 120 is a device that requests data transmission and data transmission to the server device.

The client device receives data from the server device through a notification message or an instruction message and sends a confirmation message in response to the instruction message when receiving an instruction message from the server device.

The client device may also provide information to the user through the output unit or receive input from the user through the input unit during the transmission and reception of messages with the server apparatus.

In addition, the client device can read data from the memory or write new data into the memory in the course of transmitting and receiving messages with the server device.

Hardware components such as the output unit, the input unit, and the memory of the server apparatus and the client apparatus will be described in detail with reference to FIG.

Also, the wireless communication system can configure a personal area networking (PAN) through Bluetooth technology. For example, in the wireless communication system, it is possible to quickly and safely exchange files, documents, etc. by establishing a private piconet between devices.

In addition, there are many devices for measuring human physical activity using a specific device, but there is no device that transmits measured data through Bluetooth to show a user a specific data value or the like.

Accordingly, in order to solve such a problem, the present invention proposes a method of measuring human physical activity, transmitting measured data through a Bluetooth LE, processing the data, and providing the measured data to a user.

2, the server device includes a display unit 111, a user input interface 112, a power supply unit 113, a processor 114, a memory unit 115, a Bluetooth interface 116, another communication interface 117, and a communication unit (or a transmission / reception unit 118).

The output section 111, the input section 112, the power supply section 113, the processor 114, the memory 115, the Bluetooth interface 116, the other communication interface 117 and the communication section 118, And is functionally linked to carry out the method.

The client device includes a display unit 121, a user input interface 122, a power supply unit 123, a processor 124, a memory unit 125, a Bluetooth interface (Bluetooth Interface) 126 and a communication unit (or a transmission / reception unit 127).

The output unit 121, the input unit 122, the power supply unit 123, the processor 124, the memory 125, the Bluetooth interface 126, and the communication unit 127 may be used to perform the method proposed herein Functionally connected.

The Bluetooth interfaces 116 and 126 are units (or modules) capable of request / response, commands, notifications, indication / confirmation messages, or data transmission between devices using Bluetooth technology.

The

memories

115 and 125 are units implemented in various types of devices, and are units storing various kinds of data.

The

processor

114 or 124 is a module for controlling the overall operation of the server device or the client device, and controls to process a message requesting transmission and receiving a message through a Bluetooth interface and another communication interface.

The

processors

114 and 124 may be represented by a control unit, a control unit, a controller, and the like.

The

processors

114 and 124 may include application-specific integrated circuits (ASICs), other chipsets, logic circuits, and / or data processing devices.

Wherein the processor (114,124) controls the communication unit to receive an advertisement message from a server device, transmits a scan request message to the server device, and receives a scan request from the server device in response to the scan request Controls the communication unit to receive a response message, and controls the communication unit to transmit a connection request message to the server device in order to establish a Bluetooth connection with the server device.

After the Bluetooth LE connection is established through the connection procedure, the

processors

114 and 124 may read the data using the attribute protocol from the server device, .

The

memory

115, 125 may comprise a read-only memory (ROM), a random access memory (RAM), a flash memory, a memory card, a storage medium, and /

The

communication units

118 and 127 may include a baseband circuit for processing a radio signal. When the embodiment is implemented in software, the above-described techniques may be implemented with modules (processes, functions, and so on) that perform the functions described above. The module is stored in memory and can be executed by the processor.

The

memories

115 and 125 may be internal or external to the

processors

114 and 124 and may be coupled to the

processors

114 and 124 in various well known ways.

The

output units

111 and 121 are modules for providing status information and message exchange information of a device to a user through a screen.

The power supply unit (power supply units 113 and 123) is a module that receives external power and internal power under the control of the control unit and supplies power required for operation of each component.

As we have seen, the BLE technology has a small duty cycle and can significantly reduce power consumption through a low data rate, so that the power supply requires less than 10mW (10dBm) of output power to operate each component. Power can be supplied.

The

input unit

112 or 122 is a module that allows a user to control an operation of a device by providing a user with an input of a user as a screen button.

Figure 3 shows an example of a Bluetooth low power energy topology.

Referring to FIG. 3, a device A corresponds to a master in a piconet (piconet A, shaded area) having devices B and C as slaves.

Here, a piconet is a set of devices occupying a shared physical channel in which one of a plurality of devices is a master and the remaining devices are connected to a master device.

BLE slaves do not share a common physical channel with the master. Each slave communicates with the master via a separate physical channel. There is another piconet (piconet F) having a master device F and a slave device G.

Device K is on the scatternet K. Here, a scatternet refers to a group of piconets in which a connection exists between different piconets.

The device K is the master of the device L and the slave of the device M.

Device O is also on the scatternet O. Device O is a slave of device P and slave of device Q.

As shown in FIG. 2, there are five different device groups.

1. Device D is an advertiser, and device A is an initiator (group D).

2. Device E is a scanner, and device C is an advertiser (group C).

3. Device H is the advertiser, and devices I and J are the scanners (group H).

4. Device K is also an advertiser, and device N is an initiator (group K).

5. Device R is the advertiser and device O is the initiator (group R).

Devices A and B use one BLE piconet physical channel.

Devices A and C use another BLE piconet physical channel.

In group D, device D advertises using ad events connectable on ad physical channels, and device A is an initiator. Device A may establish a connection with device D, and may add a device to piconet A.

In group C, device C advertises on the ad physical channel using some type of ad event captured by scanner device E.

Groups D and C may use different ad physical channels or use different times to avoid collisions.

The piconet F has one physical channel. Devices F and G use one BLE piconet physical channel. Device F is the master, and device G is the slave.

Group H has one physical channel. Devices H, I, and J use one BLE ad physical channel. Device H is an advertiser, and devices I and J are a scanner.

In scatternet K, devices K and L use one BLE piconet physical channel. Devices K and M use another BLE piconet physical channel.

In group K, device K advertises using ad events that are connectable over ad physical channels, and device N is an initiator. Device N may form a connection with device K. Here, the device K becomes a slave of two devices and becomes a master of one device at the same time.

On Scatternet O, devices O and P use one BLE piconet physical channel. Devices O and Q use another BLE piconet physical channel.

In group R, device R advertises using ad events that are connectable on the ad physical channel, and device O is the initiator. Device O can form a connection with device R. Here, the device O becomes a slave of the two devices and becomes the master of one device at the same time.

4, (a) shows an example of a protocol stack of Bluetooth Basic Rate / EDR (Enhanced Data Rate), (b) shows a protocol stack of Bluetooth LE (Low Energy) As shown in FIG.

4 (a), the Bluetooth BR / EDR protocol stack includes a controller stack 10 on the upper side of a host controller interface (HCI) 18, (Host Stack, 20).

The host stack (or the host module) 20 refers to a wireless transmitting / receiving module that receives a Bluetooth signal of 2.4 GHz and hardware for transmitting or receiving a Bluetooth packet. The Bluetooth module is connected to the controller module 10, And performs the operation.

The host stack 20 may include a BR / EDR PHY layer 12, a BR / EDR baseband layer 14, and a link manager layer 16.

The BR / EDR PHY layer 12 is a layer for transmitting and receiving a 2.4 GHz radio signal. When using GFSK (Gaussian Frequency Shift Keying) modulation, the BR / EDR PHY layer 12 can transmit data by hopping 79 RF channels.

The BR / EDR baseband layer 14 transmits a digital signal, selects a channel sequence hopping 1400 times per second, and transmits a time slot having a length of 625us for each channel.

The link manager layer 16 controls the overall operation (link setup, control, security) of the Bluetooth connection using the LMP (Link Manager Protocol).

The link manager layer 16 may perform the following functions.

- ACL / SCO logical transport, logical link setup and control.

- Detach: Aborts the connection and informs the partner device of the reason for the interruption.

- Power control and Role switch.

- It performs Security (authentication, pairing, encryption) function.

The host controller interface layer 18 provides an interface between the host module and the controller module so that the host provides commands and data to the controller, and the controller can provide events and data to the host.

The host stack (or host module 20) includes a logical link control and adaptation protocol (L2CAP) 21, a security manager (SM) 22, an attribute protocol 23, a generic attribute profile GATT, 24), a Generic Access Profile (GAP, 25), and a BR / EDR profile 26.

The logical link control and adaptation protocol (L2CAP, 21) may provide one bi-directional channel for transmitting data to a specific protocol or file.

The L2CAP 21 can multiplex various protocols, profiles, and the like, which are provided by the Bluetooth upper layer.

Bluetooth BR / EDR L2CAP uses dynamic channel, supports protocol service multiplexer, retransmission, streaming mode, and provides segmentation and reassembly, per-channel flow control and error control.

The security manager (SM) 22 is a protocol for authenticating a device and providing key distribution.

The General Attributes Profile (GATT) 24 may be operable as a protocol that describes how the attribute protocol 23 is used in constructing services. For example, the general property profile 24 may be operable to define how ATT attributes are grouped together into services, and be operable to describe features associated with the services.

Thus, the general attribute profile 24 and the attribute protocol (ATT) 23 may use features to describe the state and services of the device and how the features are related to one another and how they are used.

The attributes Protocol 23 and Profiles 26 define a service using BLITS BR / EDR and an application protocol for sending and receiving these data, and the Generic Access Profile (GAP) 25 ) Defines device discovery, connectivity, and means of providing information to users and provides privacy.

As shown in FIG. 4B, the Bluetooth LE protocol stack includes a controller stack 30 operable to process timing-critical wireless device interfaces, and a host capable of handling high level data And a stack (Host stack) 40.

First, the controller stack 30 may be implemented using a communication module, which may include a Bluetooth wireless device, for example, a processor module that may include a processing device, such as a microprocessor.

The host stack may be implemented as part of an operating system running on a processor module, or as instantiation of a package on an OS.

In some instances, the controller stack and host stack may operate or run on the same processing device within the processor module.

The controller stack 30 includes a physical layer (PHY) 32, a link layer 34, and a host controller interface 36.

The physical layer (PHY, wireless transmission / reception module) 32 is a layer for transmitting and receiving a 2.4 GHz radio signal, and uses a frequency hopping scheme composed of GFSK modulation and 40 RF channels.

The link layer 34, which is responsible for transmitting or receiving a Bluetooth packet, performs advertising and scanning functions using three advertising channels, and then creates a connection between devices. The link layer 34 transmits up to 257 bytes of data packets And the like.

The host stack includes a generic access profile (GAP) 40, a logical link control and adaptation protocol (L2CAP) 41, a security manager (SM) 42, an attribute protocol (ATT) (Generic Attribute Profile, GATT, 44), Generic Access Profile (25), LT profile (46). However, the host stack 40 is not limited thereto and may include various protocols and profiles.

The host stack uses L2CAP to multiplex various protocols and profiles provided by the Bluetooth host.

First, the L2CAP 41 may provide a bi-directional channel for transmitting data to a specific protocol or profile.

The L2CAP 41 may be operable to multiplex data between higher layer protocols, to segment and reassemble packages, and to manage multicast data transmissions.

Bluetooth LE uses three fixed channels (one for the signaling CH, one for the Security Manager, and one for the Attribute protocol).

On the other hand, the basic rate / enhanced data rate (BR / EDR) uses dynamic channels, and supports protocol service multiplexers, retransmission, and streaming modes.

SM (Security Manager) 42 is a protocol for authenticating a device and providing key distribution.

ATT (Attribute Protocol) 43 defines a rule for accessing data of a partner device in a server-client structure. ATT has the following six message types (Request, Response, Command, Notification, Indication, Confirmation).

1) Request and Response Message: The Request message is a request message for requesting specific information from the client device to the server device. The Response message is a response message to the Request message, which is a message transmitted from the server device to the client device.

Command message: A message transmitted from a client device to a server device in order to instruct a specific operation command. The server device does not transmit a response to the command message to the client device.

(3) Notification message: A message transmitted from the server device to the client device for notification such as an event, and the client device does not transmit a confirmation message for the notification message to the server device.

Indication and Confirm message: A message transmitted from the server device to the client device for notification such as an event. Unlike the Notification message, the client device transmits a confirmation message for the Indication message to the server device.

In the GATT profile using the attribute protocol (ATT) 43, a value for a data length in a long data request is transmitted so that the client can clearly know the data length, and the characteristic is transmitted from the server using the UUID. Value can be transmitted.

The Generalized Access Profile (GAP) 45 is a newly implemented layer for Bluetooth LE technology, used to control how role selection and multi-profile operations occur for communication between Bluetooth LE devices.

In addition, the general access profile 45 is mainly used in device discovery, connection creation and security procedures, defines a method for providing information to a user, and defines the following attribute types.

① Service: Define the basic behavior of the device by combining the behavior related to the data.

② Include: Define the relationship between services

③ Characteristics: Data value used in service

④ Behavior: Computer-readable format defined by UUID (Universal Unique Identifier, value type)

The LE profile 46 is applied to Bluetooth LE devices primarily with GATT-dependent profiles. The LE profile 46 may be, for example, Battery, Time, FindMe, Proximity, Time, Object Delivery Service, etc. The concrete contents of the GATT-based Profiles are as follows.

① Battery: How to exchange battery information

② Time: Time information exchange method

③ FindMe: Provide distance alarm service

④ Proximity: How to exchange battery information

⑤ Time: Time information exchange method

The General Attributes Profile (GATT) 44 may be operable as a protocol that describes how the attribute protocol 43 is used in constructing services. For example, the general property profile 44 may be operable to define how the ATT attributes are grouped together into services, and be operable to describe features associated with the services.

Accordingly, the general property profile 44 and the attribute protocol (ATT) 43 may use features to describe the state and services of the device and how the features are related to each other and how they are used.

Hereinafter, procedures of the Bluetooth low energy (BLE) technology will be briefly described.

The BLE procedure can be divided into a device filtering procedure, an advertising procedure, a scanning procedure, a discovery procedure, and a connecting procedure.

디바이스device 필터링Filtering 절차(Device Filtering Procedure) Procedure (Device Filtering Procedure)

The device filtering procedure is a method for reducing the number of devices that respond to requests, instructions, notifications, etc. in the controller stack.

Since it is unnecessary to respond when receiving requests from all devices, the controller stack can reduce the number of requests sent to control power consumption in the BLE controller stack.

The advertisement device or the scanning device may perform the device filtering procedure to restrict a device receiving an advertisement packet, a scan request, or a connection request.

Here, the advertisement device refers to a device that transmits an advertisement event, that is, performs an advertisement, and is also referred to as an advertiser.

The scanning device refers to a device that performs scanning, and a device that transmits a scanning request.

In a BLE, when a scanning device receives some ad packets from an ad device, the scanning device must send a scan request to the ad device.

However, if a device filtering procedure is used and scanning request transmission is unnecessary, the scanning device may ignore the advertisement packets transmitted from the advertisement device.

The device filtering procedure can also be used in the connection request process. If device filtering is used in the connection request process, it is unnecessary to transmit a response to the connection request by ignoring the connection request.

광고 절차(Advertising Procedure)Advertising Procedure

The advertisement device performs an advertisement procedure to perform an omni-directional broadcast to the devices in the area.

Here, the non-directional broadcast refers to a broadcast in all (all) directions, not a broadcast in a specific direction.

A directional broadcast, on the other hand, is a broadcast in a particular direction. A non-directional broadcast occurs without a connection procedure between an advertisement device and a device in a listening (or listening) state (hereinafter referred to as a listening device).

The ad procedure is used to establish a Bluetooth connection with a nearby initiating device.

Alternatively, the advertising procedure may be used to provide a periodic broadcast of user data to the scanning devices that are listening on the advertising channel.

In the advertising process, all advertisements (or advertisement events) are broadcast through the ad physical channel.

The ad devices may receive a scan request from the listening devices that are listening to obtain additional user data from the ad device. The advertisement device transmits a response to the scan request to the device that transmitted the scan request through the same advertisement physical channel as the advertisement physical channel that received the scan request.

The broadcast user data sent as part of the ad packets is dynamic data, while the scan response data is generally static data.

The ad device may receive a connection request from an initiating device on an ad (broadcast) physical channel. If the advertisement device has used the connectable advertisement event and the initiating device has not been filtered by the device filtering procedure, the advertisement device stops the advertisement and enters the connected mode. The ad device may start advertising again after the connection mode.

스캐닝 절차(Scanning Procedure)Scanning Procedure

The device performing the scanning, i.e., the scanning device, performs a scanning procedure to listen to the non-directional broadcast of the user data from the advertisement devices using the advertisement physical channel.

The scanning device sends a scan request to the advertisement device via the ad physical channel to request additional user data from the advertisement device. The advertisement device transmits a scan response, which is a response to the scan request, including the additional user data requested by the scanning device through the advertisement physical channel.

The scanning procedure may be used during connection with other BLE devices in the BLE piconet.

If the scanning device receives an advertisement event to be broadcast and is in an initiator mode capable of initiating a connection request, the scanning device transmits a connection request to the advertisement device via the advertisement physical channel, And start a Bluetooth connection.

When the scanning device sends a connection request to the advertisement device, the scanning device stops the initiator mode scanning for additional broadcast and enters the connection mode.

디스커버링Discovering 절차(Discovering Procedure) Procedure (Discovering Procedure)

A device capable of Bluetooth communication (hereinafter referred to as a 'Bluetooth device') performs an advertisement procedure and a scanning procedure to discover nearby devices or to be discovered by other devices in a given area.

The discovery procedure is performed asymmetrically. A Bluetooth device that is trying to find other devices nearby is called a discovering device and listens to find devices that advertise a scanable advertisement event. A Bluetooth device found and available from another device is called a discoverable device and broadcasts an advertisement event so that another device can actively scan through the advertisement (broadcast) physical channel.

Both the discovering device and the discoverable device may already be connected to other Bluetooth devices in the piconet.

연결 절차(Connecting Procedure)Connecting Procedure

The connection procedure is asymmetric, and the connection procedure requires that another Bluetooth device perform a scanning procedure while a particular Bluetooth device performs the ad procedure.

That is, an advertising procedure may be the object, and as a result, only one device will respond to the advertisement. After receiving the connectable advertisement event from the advertisement device, it can initiate the connection by sending a connection request to the advertisement device via the advertisement (brocastcast) physical channel.

Next, an operation state in the BLE technology, that is, an advertisement state, a scanning state, an initiating state, and a connection state will be briefly described.

광고 상태(Advertising State)Advertising State

The link layer LL enters the advertisement state by the instruction of the host (stack). When the link layer is in an ad state, the link layer sends ad PDUs (Packet Data Units) at the ad events.

Each advertisement event is composed of at least one advertisement PDUs, and the advertisement PDUs are transmitted through the used advertisement channel indexes. The advertisement event may be terminated when the advertisement PDU is respectively transmitted through the advertisement channel indexes used, or may terminate the advertisement event earlier if the advertisement device needs to secure space for performing other functions.

스캐닝 상태(Scanning State)Scanning State

The link layer enters the scanning state by the instruction of the host (stack). In the scanning state, the link layer listens for the advertisement channel indexes.

There are two types of scanning states: passive scanning and active scanning. Each scanning type is determined by the host.

No separate time or channel index is defined for scanning.

During the scanning state, the link layer listens for the advertisement channel index during the scanWindow duration. The scan interval (scanInterval) is defined as the interval (interval) between the start points of two successive scan windows.

If there is no conflict of scheduling, the link layer must listen for completion of all scan intervals of the scan window as indicated by the host. In each scan window, the link layer must scan another advertisement channel index. The link layer uses all available ad channel indexes.

At passive scanning, the link layer only receives packets and does not transmit any packets.

When active scanning, the link layer performs listening to rely on the advertisement PDU type and the advertisement PDU type that can request additional information related to the advertisement device to the advertisement device.

개시 상태(Initiating State)Initiating State

The link layer enters the initial state by the instruction of the host (stack).

When the link layer is in the initiating state, the link layer performs listening to the advertisement channel indexes.

During the initiation state, the link layer listens for the advertisement channel index during the scan window period.

연결 상태(connection state)Connection state

The link layer enters a connection state when the device performing the connection request, i. E., The initiating device sends a CONNECT_REQ PDU to the ad device, or when the ad device receives a CONNECT_REQ PDU from the initiating device.

After entering the connection state, a connection is considered to be created. However, it does not need to be considered to be established at the time the connection enters the connection state. The only difference between the newly created connection and the previously established connection is the link layer supervision timeout value.

When two devices are connected, the two devices act in different roles.

The link layer that performs the master role is called the master, and the link layer that acts as the slave is called the slave. The master controls the timing of the connection event, and the connection event refers to the time at which the master and the slave are synchronized.

Hereinafter, a packet defined in the Bluetooth interface will be briefly described. BLE devices use the packets defined below.

패킷 포맷(Packet Format)Packet Format

The link layer has only one packet format used for both the ad channel packet and the data channel packet.

Each packet consists of four fields: a preamble, an access address, a PDU, and a CRC.

When one packet is transmitted on the ad physical channel, the PDU will be an ad-channel PDU, and when one packet is transmitted on the data physical channel, the PDU will be a data channel PDU.

광고 채널 Ad channel PDUPDU (Advertising Channel (Advertising Channel PDUPDU ))

The advertisement channel PDU (Packet Data Unit) has a 16-bit header and payloads of various sizes.

The PDU type field of the advertisement channel PDU included in the header indicates the PDU type as defined in Table 1 below.

광고 Advertising PDUPDU (Advertising (Advertising PDUPDU ))

The following ad channel PDU types are called ad PDUs and are used in specific events.

ADV_IND: connectable non-directional ad event

ADV_DIRECT_IND: Attachable directional ad event

ADV_NONCONN_IND: Non-directional ad event not reachable

ADV_SCAN_IND: Scannable non-directional ad event

The PDUs are transmitted in the link layer in the advertisement state and received by the link layer in the scanning state or the initiating state.

스캐닝 scanning PDUPDU (Scanning (Scanning PDUPDU ))

The following advertisement channel PDU type is called a scanning PDU and is used in the state described below.

SCAN_REQ: Sent by the link layer in the scanning state, and received by the link layer in the advertisement state.

SCAN_RSP: sent by the link layer in the advertisement state, and received by the link layer in the scanning state.

개시 Start PDUPDU (Initiating (Initiating PDUPDU ))

The following advertisement channel PDU type is called a start PDU.

CONNECT_REQ: Sent by the link layer in the initiated state, and received by the link layer in the advertised state.

데이터 채널 Data channel PDUPDU (Data Channel (Data Channel PDUPDU ))

A data channel PDU may have a 16-bit header, payloads of various sizes, and may include a Message Integrity Check (MIC) field.

The procedures, states, packet formats, and the like in the BLE technology discussed above can be applied to perform the methods proposed in this specification.

5 is a diagram illustrating an example of a structure of a Bluetooth low power energy GATT Profile.

Referring to FIG. 5, a structure for exchange of profile data of Bluetooth low power energy can be examined.

Specifically, the GATT (Generic Attribute Profile) defines a method of exchanging data using services and characteristics between Bluetooth LE devices.

In general, a Peripheral device (e.g., a sensor device) serves as a GATT server and has a definition of Service and Characteristic.

To read or write data, the GATT client sends a data request to the GATT server, and all transactions start at the GATT client and receive a response from the GATT server.

The GATT-based operation structure used in the Bluetooth LE is based on a profile, a service, and a characteristic, and can have a vertical structure as shown in FIG.

The Profile may consist of one or more services, which may consist of one or more characteristics or other services.

The service serves to divide data into logical units and may include one or more characteristics or other services. Each service has a 16-bit or 128-bit separator called a Universal Unique Identifier (UUID).

The above characteristic is the lowest unit in the GATT-based operation structure. The characteristic includes only one data, and has a 16-bit or 128-bit UUID similar to the service.

The attribute is defined as a value of various information, and one attribute is required to contain each information. The above properties Several continuous attributes can be used.

The attribute consists of four components and has the following meaning.

- handle: the address of the attribute

- Type: Type of attribute

- Value: the value of the attribute

- Permission: Access to the property

In the present invention, a sensor measures and stores human activity using a GATT-based operation structure of the Bluetooth LE, and a method for a client to retrieve information stored from the sensor.

6, for the Bluetooth LE connection between the first device 300 and the second device 400, the first device 300 transmits an advertisement message to the second device 300 (S6010).

As described above, the advertisement message is used to provide its own information to another device using the Bluetooth LE, and may include various information such as service information and user information provided by the device.

The second device 400 confirms the information included in the advertisement message transmitted by the first device 300 and transmits a connection request message to the first device 300 to request the Bluetooth LE connection message (S6020), and the first device 300 and the second device 400 form a Bluetooth LE (Low Energy) connection (S6030).

Bluetooth standard technology (for example, Bluetooth Specification V4.0) distinguishes core specifications from BR / EDR (Basic Rate / Enhanced Data Rate) and LE (Low Energy). Here, BR / EDR is a wireless communication technology applied to many products, which has dominant market dominance of short-range wireless personal area network (WPAN) technology.

And Bluetooth LE (Bluetooth Low Energy) (BLE) is a technology announced since V4.0 of Bluetooth standard and is designed for high energy efficiency compared to existing Bluetooth BR / EDR.

These BLEs communicate using the Industry-Science-Medical (ISM) frequency band (or band) (e.g., 2.4-2.4835 GHz) in the 2.4 GHz band. As described above, in the BLE, three advertisement channels are used for device discovery. At this time, two channels among the three designated primary advertisement channels are present at a band edge. Will be described with reference to the following drawings. In the present invention, the three basic advertisement channels are collectively referred to as a primary advertising channel set. The three advertisement channels included in the basic advertisement channel set may be preset in the device using the Bluetooth protocol, and in this specification, the

channel indexes

37, 38 and 39 are assumed to be premised, but the present invention is not limited thereto Alternatively, it may have a different channel index value.

Referring to FIG. 7, a total of 40 channels from CH0 to CH39 can be used within the operating frequency band of the BLE, and frequency bands can be assigned to each channel. As described above, in the BLE technology, the 2.4 GHz ISM band is used as the operating frequency, and specifically, the frequency band of 2400 to 2483.5 MHz can be used. In this case, a frequency band may be allocated to each of the k-th channel (where k = 0, ..., 39) to have a center frequency of 2402 + k * 2 MHz.

The default ad channel set 7010 may include CH37, CH38, and CH39 as illustrated in FIG. The default ad channel set 7010 may comprise a channel that is used only for advertising purposes. On the other hand, the data channel set 7020 represents the remaining data channels except for the three advertisement channels included in the basic advertisement channel set 7010 among the entire channels, and the data channel represents a channel used for data transmission / reception.

In the present invention, the data channel set 7020 may be referred to as a secondary advertisement channel set. That is, in the following embodiment, in the remaining data channels excluding the three advertisement channels included in the basic advertisement channel set 7010, one or more data channels in the data channel set 7020 may be used as supplementary advertisement channels have.

At this time, among the advertisement channels of the basic advertisement channel set 7010, CH37 and CH39 are located at the boundaries of the BLE frequency band including 40 channels. Some channels among the basic advertisement channel set 7010 used only for advertisement or scanning may be located on both sides of the entire frequency band, resulting in a problem that efficiency of advertisement and device search due to interference is lowered. Will be described with reference to the following drawings.

Referring to FIG. 8, interference due to other communication techniques may occur at the boundary of the BLE frequency band using the 2.4 GHz ISM band. Specifically, at the border around CH37, there is an auction plan by Ofcom (UK Broadcasting Commission) for the LTE service in the band 2350-2390 MHz.

In the vicinity of the boundary including Ch39, a terrestrial low-power service band (2473-2495 MHz) by Globalstar (US satellite phone service provider) is proposed following the mobile satellite service band (2483.5-2495 MHz) currently provided.

In this way, interference may occur at the boundary of the BLE frequency band due to other communication techniques. Therefore, a channel having

channel indexes

37 and 39 located at the boundary of the BLE frequency band among the basic advertisement channel set 8010 is used for the advertisement There is a problem of lowering the efficiency of the advertisement.

Recently, a method of adding an advertisement channel having a channel index of 40 in addition to the three existing advertisement channels in addition to the basic advertisement channel set 8010 is being discussed.

Accordingly, the present invention proposes a new link layer protocol and a new host controller interface (HCI) for performing advertisement using four channels.

In particular, the present invention proposes a protocol for exchanging channel index information used for advertisement / scanning between devices in an environment where advertisements are performed using four channels.

In addition, the present invention proposes a channel map for advertisement or scanning in an environment in which advertisements are performed using four channels.

According to the embodiment of the present invention, it is possible to reduce the interference occurring at the band boundary and to search the device with high reliability.

In one embodiment of the present invention, attributes may be defined as shown in FIG. 9 when a total of four advertisement channels with channel indexes of 37, 38, 39 and 40 are used.

An advertisement / scanning channel update request can be performed in the GATT-based profile through the attribute shown in Fig. Specifically, the attribute may include an attribute handle, an attribute type, an attribute value, and an attribute permission attribute (or field).

At this time, the attribute handle field may include identification information or index information of the proposed attribute. The attribute type field may include UUID information of an advertisement channel protection (or an advertisement channel protection mode) using four advertisement channels. In addition, the attribute permission may include information on Readable without authentication or Authorization, Writable with authentication or authorization.

In particular, the attribute value field may include at least one of an advertisement channel property (or an advertisement channel map property, an advertisement channel set property, and an advertisement channel update property) and / or a scanning channel property (or a scanning channel map property, Which may be referred to as channel update characteristics. In the embodiment of the present invention, not only the channels advertised by the device but also the information about the channels to be scanned are transmitted through the advertisement channel characteristic and the scanning channel characteristic, . Will be described with reference to the following drawings.

Referring to FIG. 10 (a), an example of an advertisement channel characteristic is shown. The advertisement channel characteristic may have a value of 0 to 3 bits (or an index) and may indicate the availability of a total of four advertisement channels from 37 to 40 according to each bit value.

Referring to FIG. 10 (b), an example of a scanning channel characteristic is shown. The scanning channel characteristic may have a value of 0 to 3 bits (or an index), and may indicate the availability of a total of four scanning channels from 37 to 40 according to each bit value.

In the embodiment of the present invention, information on a channel advertised by the device and information on a channel to be scanned can be transmitted through the advertisement channel characteristic and the scanning channel characteristic shown in FIG.

Referring to FIG. 11A, a host of a server device transmits a control message instructing update of an advertisement channel to a link layer (LL) of a server device through a host controller interface (HCI) ). In the present invention, the control message indicating the update of the advertisement channel may be referred to as an LE Set Advertising Channel Update command.

The LE Set Advertising Channel Update command may include an ad channel map parameter. The advertisement channel map parameter may have the same format as the advertisement channel characteristic described above with reference to FIG. 10 (a).

Referring to FIG. 11 (b), the host of the server device can transmit a control message instructing the update of the scanning channel to the LL of the server device through the HCI command. In the present invention, the control message indicating the update of the scanning channel may be referred to as an LE Set Scanning Channel Update command.

The LE Set Scanning Channel Update command may include a scanning channel map parameter. The scanning channel map parameter may have the same format as the scanning channel characteristic described above with reference to FIG. 10 (b).

An advertiser may perform an advertisement using a physical advertisement channel set determined (or updated) by an advertisement channel map parameter (or an advertisement channel characteristic). Then, the scanner can perform scanning using the physical advertisement channel set determined (or updated) by the scanning channel map parameter (or the scanning channel characteristic).

In an embodiment of the present invention, the host of the server device may send a control message including the advertisement channel map and the scanning channel map information to the LL of the server device via the HCI command.

Referring to FIG. 12 (a), in the present invention, the control message indicating the control message including the advertisement channel map and the scanning channel map information may be referred to as an LE Set Advertising Parameters command. The LE Set Advertising Parameters command may include an advertisement channel map and a scanning channel map parameter, including various parameters related to advertisement channel setting. The advertisement channel map and the scanning channel map parameters may have the same format as the advertisement channel characteristic and the scanning channel characteristic described above with reference to FIG.

12 (b), in the present invention, the control message indicating the control message including the advertisement channel map and the scanning channel map information may be referred to as an LE Set Extended Advertising Parameters command. The LE Set Extended Advertising Parameters command may include an advertisement channel map and a scanning channel map parameter, including various parameters related to advertisement channel setting. The advertisement channel map and the scanning channel map parameters may have the same format as the advertisement channel characteristic and the scanning channel characteristic described above with reference to FIG.

As described above, a basic advertisement channel set can be configured using four advertisement channels, and advertisement or scan can be performed using the corresponding basic advertisement channel. Hereinafter, a method of applying a protection mode of an advertisement channel according to presence or absence of interference will be described using a basic advertisement channel including three advertisement channels.

In one embodiment of the present invention, a protected mode is applied when interference is present, and a non-protected mode may be applied if no interference is present. The BLE device may be aware of the presence of interference in existing ad channel sets in a variety of ways. For example, the device may be aware of the presence or absence of interference at a higher level, using an application, or may receive relevant information from a user.

In the absence of interference, i. E., In the non-protected mode, the advertiser can carry out the same advertisement as before. If there is interference, i.e., in protected mode, the advertiser can perform ads on four ad channels (new ad channel addition) or on three ad channels (interfering channel replacement). Then, the scanner determines whether or not the advertiser is in the protection mode, and when the protection mode is applied, scanning can be performed using the four channels.

In the case of using four advertisement channels in the protection mode, there is an advantage that the scanner is not required to know which channel the interference exists in, and that advertisement / scan can be performed using the four promised channels in advance. On the other hand, the advertising efficiency may be degraded due to continuous use of the channel in which the interference exists. In this case, it is necessary for the advertiser and the scanner to share the use of the protection mode.

When three advertisement channels are used in the protection mode, the search time or search efficiency can be increased because the advertisement / scan is not performed in the channel where the interference exists. On the other hand, advertisers and scanners need to share about which channel to discard, or which channel has interference. Even in this case, it is necessary for the advertiser and the scanner to share the use of the protection mode.

Referring to FIG. 13, the first device may request the second device to update (or change) the advertisement channel map and / or the scanning channel map based on the GATT. 13, the first device may be a scanner device and the second device may be an advertiser device.

Specifically, the host (or the attribute) of the first device transmits an attribute write request message including the advertisement channel map information and the scanning channel map information to the host of the second device (S13010). The host of the second device transmits an attribute response request message of the first device to the host of the first device in response to the write request message (S13020).

That is, the first device and the second device can set the advertisement channel set and the scanning channel set based on the GATT in the connected state. In this case, a step of forming a Bluetooth LE connection between the first device and the second device may be performed prior to steps S13010 and S13020.

The host of the second device transmits an LE Set Advertising Channel Update command to the link layer (LL) of the second device to update the advertisement channel map (S13030). At this time, the HCI command described in FIG. 11 (a) can be used for the LE Set Advertising Channel Update command.

The LL of the second device may transmit a command completion message to the host of the second device indicating that the command has been successfully completed (S13040). If the existing three advertisement channels are changed to four advertisement channels, the protection mode can be triggered thereby. Thereafter, the advertisement channel (or the advertisement channel map, the advertisement channel set) may be changed. After the connection with the first device is released, the second device may perform advertisement using the updated advertisement channel in step S13040 in the reconnection step.

The host of the second device transmits an LE Set Scanning Channel Update command to the LL of the second device to update the scanning channel map (S13050). At this time, the LE Set Scanning Channel Update command may be the HCI command described above with reference to FIG. 11 (b).

The LL of the second device may transmit a command completion message indicating that the command has been successfully completed to the host of the second device (S13060). If the scanning channel is changed from the existing three scanning channels to the four scanning channels, the protection mode can be triggered thereby. Thereafter, the scanning channel (or the scanning channel map, the scanning channel set) may be changed. After the connection with the first device is released, in the reconnection step, the second device may recognize that the first device performs the scanning using the updated scanning channel in step S13060.

14, it is assumed that the first device is a scanner device and the second device is an advertiser device.

The second device receives a write request message instructing to change an advertising channel map and a scanning channel map from the first device (S14010).

As described above with reference to FIGS. 9 and 10, the write request message may include an advertisement channel map characteristic and a scanning channel map characteristic information. The advertisement channel map characteristic may include at least one of index information of an available advertisement channel or advertisement channel information included in the advertisement channel map. The scanning channel map characteristic may include at least one of an available scanning channel And information on the number of scanning channels included in the scanning channel map.

The second device transmits a write response message to the first device in response to the write request message (S14020).

The host of the second device transmits a host controller interface (HCI) command instructing the controller of the second device to change the advertisement channel map based on the advertisement channel map characteristic (S14030).

The HCI command may be configured with the HCI command described above with reference to FIGs. 11 and 12. FIG.

The controller of the second device transmits an advertisement message to the first device using the changed advertisement channel map (S14040).

As described above, the advertisement channel map may be modified to additionally include at least one advertisement channel in addition to the existing advertisement channel map including three advertisement channels.

13, the host of the second device can transmit the HCI command instructing the controller of the second device to change the scanning channel map based on the scanning channel map characteristic. In this case, the scanning channel map may be modified so as to additionally include at least one scanning channel in addition to the existing scanning channel map including three advertisement channels.

The embodiments described above are those in which the elements and features of the present invention are combined in a predetermined form. Each component or feature shall be considered optional unless otherwise expressly stated. Each component or feature may be implemented in a form that is not combined with other components or features. It is also possible to construct embodiments of the present invention by combining some of the elements and / or features. The order of the operations described in the embodiments of the present invention may be changed. Some configurations or features of certain embodiments may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments. It is clear that the claims that are not expressly cited in the claims may be combined to form an embodiment or be included in a new claim by an amendment after the application.

Embodiments in accordance with the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of hardware implementation, an embodiment of the present invention may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs) field programmable gate arrays, processors, controllers, microcontrollers, microprocessors, and the like.

In the case of an implementation by firmware or software, an embodiment of the present invention may be implemented in the form of a module, a procedure, a function, or the like for performing the functions or operations described above. The software code can be stored in memory and driven by the processor. The memory is located inside or outside the processor and can exchange data with the processor by various means already known.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. Accordingly, the foregoing detailed description is to be considered in all respects illustrative and not restrictive. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined by the appended claims. , Substitution or addition, or the like.

Claims

A method for discovery of an adjacent device in a wireless communication system using Bluetooth LE (Low Energy), the method being performed in a second device,

Receiving a write request message instructing to change an advertising channel map and a scanning channel map from the first device,

Wherein the write request message includes an advertisement channel map characteristic and a scanning channel map characteristic;

Transmitting a write response message to the first device in response to the write request message;

The host of the second device transmits a host controller interface (HCI) command for instructing the controller of the second device to change the advertisement channel map based on the advertisement channel map characteristic step; And

The controller of the second device sending an advertising message to the first device using the modified advertisement channel map.
The method according to claim 1,

Wherein the advertisement channel map characteristic includes at least one of index information of an available advertisement channel or information on the number of advertisement channels included in the advertisement channel map,

Wherein the scanning channel map characteristic includes at least one of index information of available scanning channels or information on the number of scanning channels included in the scanning channel map.
The method according to claim 1,

Wherein the advertisement channel map is further modified to include at least one advertisement channel in addition to an existing advertisement channel map including three advertisement channels.
The method according to claim 1,

The host of the second device sending an HCI command instructing the controller of the second device to change the scanning channel map based on the scanning channel map characteristic.
5. The method of claim 4,

Wherein the scanning channel map is modified to additionally include at least one scanning channel in addition to an existing scanning channel map including three advertisement channels.
A second device for discovery of an adjacent device in a wireless communication system using Bluetooth LE (Low Energy)

A communication unit for wirelessly or wiredly communicating with an external device; And

And a processor operatively connected to the communication unit,

Receiving a write request message instructing to change an advertising channel map and a scanning channel map from the first device,

Wherein the write request message includes an advertisement channel map characteristic and a scanning channel map characteristic;

Sending a write response message to the first device in response to the write request message;

The host of the second device transmits a host controller interface (HCI) command for instructing the controller of the second device to change the advertisement channel map based on the advertisement channel map characteristic ; And

Wherein the controller of the second device transmits an advertising message to the first device using the modified advertisement channel map.
The method according to claim 6,

Wherein the advertisement channel map characteristic includes at least one of index information of an available advertisement channel or information on the number of advertisement channels included in the advertisement channel map,

Wherein the scanning channel map characteristic includes at least one of index information of available scanning channels or information on the number of scanning channels included in the scanning channel map.
The method according to claim 6,

Wherein the advertisement channel map is further modified to include at least one advertisement channel in addition to an existing advertisement channel map including three advertisement channels.
The method according to claim 6,

And the host of the second device sends an HCI command instructing the controller of the second device to change the scanning channel map based on the scanning channel map characteristic.
10. The method of claim 9,

Wherein the scanning channel map is further modified to include at least one scanning channel in addition to an existing scanning channel map including three advertisement channels.