This application is the National Stage filing under 35 U.S.C. 371 of International Application No. PCT/KR2017/014752, filed on Dec. 14, 2017, the contents of which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates to a device for V2X communication and a communication method thereof, and more particularly to configuration of a service advertisement message for receiving services through V2X communication.

BACKGROUND ART

The present disclosure relates to a V2X communication device and a communication method thereof and, more particularly, to a communication method of a hybrid V2X communication device performing communication based on a WLAN V2X communication protocol and a cellular V2X communication protocol.

DISCLOSURE

Technical Problem

Various services can be provided through V2X communication. Furthermore, a plurality of frequency bands was used to provide the various services. Even in such an environment, highly reliable forwarding and providing of safety services are very important matters considering characteristics of vehicle communication.

A service advertisement message is sent to provide services through the V2X communication. As the V2X communication environment develops, it is necessary to improve and reinforce the service advertisement message.

Technical Solution

In order to solve the above-described and other problems, in one aspect, there is provided a communication method of a V2X communication device comprising accessing a first channel; receiving a network protocol data unit (NPDU) including a service advertisement message (SAM) on the first channel; and based on the service advertisement message, accessing a service channel and receiving service data, wherein the NPDU includes a N-header, a T-header, and a body, wherein the N-header provides network related information, the T-header provides transport related information, and the body includes the service advertisement message, wherein the service advertisement message provides service information and information about the service channel on which a service is provided.

The service advertisement message may include a header part and a body part. The header part may include at least one of SAM ID information, SAM count information, and SAM extension information, and the body part may include service information and channel information.

The N-header may include channel busy ratio (CBR) information on the first channel and additional CBR information on an additional channel, and the CBR information may indicate a percentage of channel usage for a specific channel.

The N-header may include at least one of multichannel access mode information and multichannel access interval information.

The multichannel access mode information may indicate at least one of an asynchronous multichannel access mode, an overlapping multichannel access mode, a sequential multichannel access mode, or a mixed multichannel access mode.

The N-header may include at least one of transmission mode information of the service advertisement message and service channel number information on which the service advertisement message is transmitted.

The transmission mode information of the service advertisement message may indicate at least one of a first mode in which the service advertisement message is transmitted on a control channel, a second mode in which the service advertisement message is transmitted on one reference service channel, a third mode in which the service advertisement message is transmitted on all of SCHs, or a fourth mode in which channels are divided into a plurality of sub-bands, and the service advertisement message is transmitted on one reference service channel in the divided sub-band.

In another aspect, there is provided a V2X communication device comprising a memory configured to store data; a communication unit configured to transmit and receive a radio signal; and a processor configured to control the memory and the communication unit, wherein the V2X communication device is configured to access a first channel, receive a network protocol data unit (NPDU) including a service advertisement message (SAM) on the first channel, and based on the service advertisement message, access a service channel and receive service data, wherein the NPDU includes a N-header, a T-header, and a body, wherein the N-header provides network related information, the T-header provides transport related information, and the body includes the service advertisement message, wherein the service advertisement message provides service information and information about the service channel on which a service is provided.

Advantageous Effects

The present disclosure can help V2X devices to select channel when accessing a multichannel by providing CBR information on an additional channel by a NPDU including a service advertisement message. Further, the V2X device provides/receives services with reference to CBR information on a plurality of channels, and thus can distribute traffic concentration for a specific channel and improve resource usage efficiency. The present disclosure can allow the V2X device to flexibly change a multichannel access mode by transmitting multichannel access mode information. The present disclosure supports various transmission modes and enables a flexible operation of the V2X device by transmitting transmission mode information of the service advertisement message.

