WO2019132083A1

WO2019132083A1 - V2x communication device and geonetworking transmission method

Info

Publication number: WO2019132083A1
Application number: PCT/KR2017/015763
Authority: WO
Inventors: 김진우; 고우석; 백서영
Original assignee: 엘지전자(주)
Priority date: 2017-12-29
Filing date: 2017-12-29
Publication date: 2019-07-04

Abstract

A GeoNetworking transmission method for a V2X communication device is disclosed. The GeoNetworking transmission method according to an embodiment of the present invention can comprise the steps of: receiving a GeoNetworking packet, wherein the GeoNetworking packet includes I2I priority information for indicating whether I2I forwarding is prioritized and I2I lifetime information for providing I2I lifetime-related information; determining, on the basis of the I2I priority information, whether the I2I forwarding is prioritized; determining, on the basis of the I2I lifetime information, whether the lifetime of the I2I forwarding has expired when the I2I forwarding is prioritized; and transmitting the GeoNetworking packet when the lifetime of the I2I forwarding has not expired.

Description

V2X communication device and geo-networking transfer method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for V2X communication and a geo-networking transmission method thereof, and more particularly, to a packet transmission method capable of reliably transmitting a geo-networking packet.

In recent years, vehicles have become a result of complex industrial technology that is a fusion of electric, electronic, and communication technologies centering on mechanical engineering. In this respect, vehicles are also called smart cars. Smart cars have been providing various customized mobile services as well as traditional vehicle technologies such as traffic safety / complicatedness by connecting drivers, vehicles, and transportation infrastructures. This connectivity can be implemented using V2X (Vehicle to Everything) communication technology.

Various services can be provided through V2X communication. In addition, a plurality of frequency bands have been used to provide various services. In this environment, reliable communication and delivery of safety service is very important because of the nature of vehicle communication.

In V2X communication, a geo-networking transmission method using hopping can be used to transmit data outside the transmission range. In geo-networking transmissions, packet forwarding algorithms can be used for data hopping and destination delivery. Particularly, in the V2X communication environment where the communication environment changes dynamically, the efficiency and reliability of the packet forwarding algorithm must be considered.

The geo-networking transmission method of a V2X communication apparatus according to an exemplary embodiment of the present invention is a method of receiving a geo-networking packet, the geo-networking packet including I2I priority information indicating whether I2I forwarding has priority, And I2I lifetime information providing lifetime related information; Determining whether I2I forwarding is prioritized based on the I2I priority information; If the I2I forwarding has a priority, determining whether the lifetime of the I2I forwarding has expired based on the I2I lifetime information; And transmitting the geo-networking packet if the lifetime of the I2I forwarding has not expired.

As an embodiment, the step of transmitting the geo-networking packet comprises: determining as a forwarder a V2X communication device capable of I2I forwarding based on location information, the location information comprising at least one neighbor V2X communication executing a geo-networking protocol Comprising: < / RTI > And transmitting the geo-networking packet to the forwarder.

In an embodiment, the location information is configured based on a beacon packet received from the at least one neighbor V2X communication device, the beacon packet comprising I2I indicating the I2I forwarding capability of the V2X communication device transmitting the beacon packet And may include capability information.

In an embodiment, the beacon packet includes IRL information including information about at least one neighboring RIS in the vicinity of the V2X communication device transmitting the beacon packet, the IRL information indicating the number of neighboring RIS An RIS count field, and an RIS geolocation field that provides location information for the neighboring RIS.

In an embodiment, the I2I lifetime information includes lifetime type information indicating a type of the I2I lifetime and lifetime value information indicating a value of the I2I lifetime according to the type, wherein the type of the I2I lifetime is the lifetime type of the I2I lifetime May be a first type indicated by the maximum allowed time or a second type indicated by the number of hops remaining in the I2I lifetime.

In an embodiment, when the type of I2I lifetime is a first type, the lifetime value information indicates a value of a maximum allowed time until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding, When the type of I2I lifetime is the second type, the lifetime value information may indicate a value of the remaining hop count until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding.

A V2X communication apparatus according to an embodiment of the present invention includes a memory for storing data; A communication unit for transmitting and receiving a radio signal including geo-networking packets; And a processor for controlling the memory and the communication unit, the processor receiving a geo-networking packet, the geo-networking packet including I2I priority information indicating that I2I forwarding has priority and I2I priority information indicating I2I forwarding priority, I2I lifetime information providing lifetime related information; Determine whether I2I forwarding is prioritized based on the I2I priority information; If the I2I forwarding has a priority, determining whether the lifetime of the I2I forwarding has expired based on the I2I lifetime information; If the lifetime of the I2I forwarding has not expired, the geo-networking packet can be transmitted.

According to the present invention, the efficiency of multi-hop packet delivery using V2V communication can be enhanced by transmitting geo-networking packets using an infrastructure network. Also, by using the geo-networking packet tunneling technique, transmission delay can be minimized even when an upper layer protocol is incompatible when connecting an infrastructure network. Additional and various other effects of the present invention are described together with the constitution of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

1 shows a protocol structure of an ITS system according to an embodiment of the present invention.

2 shows a packet structure of a network / transport layer according to an embodiment of the present invention.

3 is a header structure of a geo-networking packet according to an embodiment of the present invention, and shows a structure of a basic header and a common header.

FIG. 4 illustrates a geographically-scoped unicast (GUC) type geo-networking method according to an embodiment of the present invention and a GUC packet header structure according to the method.

5 is a topologically scoped broadcast (TSB) type geo-networking method according to another embodiment of the present invention and a TSB packet header structure according to the method.

6 illustrates a SHB (Single Hop Broadcast) type geo-networking method and an SHB packet header configuration according to another embodiment of the present invention.

FIG. 7 illustrates a Geographically-Scope Broadcast (GBC) / Geographic-Scoped Anycast (GAC) type geo-networking method and a BC / GAC packet header according to another embodiment of the present invention.

FIG. 8 illustrates a beacon type geo-networking according to another embodiment of the present invention, and a beacon packet header according to the present invention.

FIG. 9 shows a structure of an LS (Location Service) request packet header and an LS response packet header according to an embodiment of the present invention.

FIG. 10 shows position vector information according to an embodiment of the present invention.

11 shows a packet forwarding method of a greedy forwarding algorithm according to an embodiment of the present invention.

12 illustrates a packet delivery method of a non-area contention-based algorithm according to an embodiment of the present invention.

13 shows a packet delivery method of an area contention-based algorithm according to an embodiment of the present invention.

14 shows a multi-channel allocation used in an ITS system operation according to an embodiment of the present invention.

FIG. 15 illustrates a geo-networking packet forwarding method of an ITS station according to an embodiment of the present invention.

16 illustrates a method for delivering an ITS message using an infrastructure in a C-ITS according to an embodiment of the present invention.

FIG. 17 shows a protocol stack of an ITS station for an ITS message delivery method using the infrastructure of FIG. 16;

18 illustrates a method of transmitting a geo-networking packet using an infrastructure network according to an embodiment of the present invention.

FIG. 19 illustrates a method of transmitting a geo-networking packet using an infrastructure network according to another embodiment of the present invention.

20 shows a structure of a geo-networking header according to an embodiment of the present invention.

Figure 21 shows a first I2I signaling field according to an embodiment of the present invention.

22 shows a second I2I signaling field according to an embodiment of the present invention.

23 shows a structure of a geo-networking header according to another embodiment of the present invention.

24 shows a structure of an IRL field according to an embodiment of the present invention.

25 illustrates a method for delivering geo-networking packets using an infrastructure according to an embodiment of the present invention.

26 illustrates a hybrid geo-networking method utilizing I2I forwarding via cellular handover in accordance with an embodiment of the present invention.

27 is a flow diagram illustrating a geo-networking operation of a source station in accordance with an embodiment of the present invention.

FIG. 28 is a flowchart illustrating a geo-networking operation of a VIS-in forwarding station according to an embodiment of the present invention.

29 is a flow diagram illustrating the geo-networking operation of a forwarding station that is an RIS adjacent to a source station in accordance with an embodiment of the present invention.

FIG. 30 is a flowchart illustrating a geo-networking operation of a forwarding station that is an RIS adjacent to a destination station according to an embodiment of the present invention.

31 shows a configuration of a V2X communication apparatus according to an embodiment of the present invention.

32 is a flowchart illustrating a geo-networking transmission method of a V2X communication apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description with reference to the attached drawings is for the purpose of illustrating preferred embodiments of the present invention rather than illustrating only embodiments that may be implemented according to embodiments of the present invention. The following detailed description includes details in order to provide a thorough understanding of the present invention, but the present invention does not require all of these details. The present invention is not limited to the embodiments described below. Multiple embodiments or all of the embodiments may be used together, and specific embodiments may be used as a combination.

Most of the terms used in the present invention are selected from common ones widely used in the field, but some terms are arbitrarily selected by the applicant and the meaning will be described in detail in the following description as necessary. Accordingly, the invention should be understood based on the intended meaning of the term rather than the mere name or meaning of the term.

The present invention relates to a V2X communication device, wherein the V2X communication device is included in an Intelligent Transport System (ITS) system to perform all or some of the functions of the ITS system. V2X communication devices can communicate with vehicles and vehicles, vehicles and infrastructure, vehicles and bicycles, and mobile devices. The V2X communication device may be abbreviated as a V2X device. As an embodiment, the V2X device may correspond to an on-board unit (OBU) of a vehicle or may be included in an OBU. The OBU may also be referred to as OBE (On Board Equipment). The V2X communication device may correspond to an infrastructure's road side unit (RSU) or may be included in an RSU. The RSU may also be referred to as RSE (Road Side Equipment). Alternatively, the V2X communication device may correspond to the ITS station (ITS-S) or may be included in the ITS station. Any OBU, RSU, mobile device, etc. performing V2X communication may be referred to as an ITS station or a V2X communication device. In geo-networking communications, a V2X communications device may be referred to as a router.

The V2X communication device can communicate based on various communication protocols. The V2X communication device can implement IEEE 1609.1 ~ 4 Wireless In Vehicular Environments (WAVE) protocols. In this case, the V2X communication device may be referred to as a WAVE device or a WAVE communication device.

The V2X communication device can transmit a Cooperative Awareness Message (CAM) or a Decentralized Environmental Notification Message (DENM). The CAM is distributed in the ITS network and provides information about at least one of the presence, location, communication state, or operating state of the ITS station. DENM provides information about detected events. The DENM may provide information about any driving situation or event detected by the ITS station. For example, DENM can provide information on situations such as emergency electronic brakes, vehicle accidents, vehicle problems, traffic conditions, and so on.

Application layer: The application layer can implement and support various use cases. For example, the application may provide road safety, Efficient Traffic Information, and other application information.

Facilities layer: The facilities layer can support various applications defined at the application layer effectively. For example, the facility layer can perform application support, information support, and session / communication support.

Access layer: The access layer can transmit the message / data received from the upper layer through the physical channel. For example, the access layer may include an ITS-G5 wireless communication technology based on IEEE 802.11 and / or 802.11p standards based communication technology, a physical transmission technology of the IEEE 802.11 and / or 802.11p standard, a satellite / And can perform / support data communication based on 2G / 3G / 4G (LTE) / 5G wireless cellular communication technology, broadband terrestrial digital broadcasting technology such as DVB-T / T2 / ATSC, GPS technology and IEEE 1609 WAVE technology.

Network and Transport Layer: The network / transport layer can configure a network for vehicle communication between homogenous and heterogeneous networks by using various transport protocols and network protocols.

The transport layer is the link layer between the services provided by the upper layer (session layer, presentation layer, application layer) and lower layer (network layer, data link layer, physical layer). The transport layer can manage the transmission data to arrive at the destination exactly. At the transmitting end, the transport layer processes the data into packets of reasonable size for efficient data transmission, and at the receiving end, the transport layer can perform processing to recover the received packets back to the original file. As an example, protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and Basic Transport Protocol (BTP) may be used as the transport protocol.

The network layer manages the logical address and can determine the delivery path of the packet. The network layer can receive the packet generated at the transport layer and add the logical address of the destination to the network layer header. As an embodiment, the packet path may be considered for unicast / broadcast between vehicles, between vehicle and fixed stations, and between fixed stations. As an example, Geo-Networking, IPv6 support with mobility support, and IPv6 over geo-networking may be considered as networking protocols.

The ITS architecture may further include a management layer and a security layer.

The transport layer may generate BTP packets, and the network layer may encapsulate BTP packets to generate geo-networking packets. Geo-networking packets can be encapsulated in LLC packets. In the embodiment of FIG. 2, the data may comprise a message set, and the message set may be a basic safety message.

BTP is a protocol for transmitting messages such as CAM and DENM generated by the facility layer to the lower layer. The BTP header consists of A type and B type. The A-type BTP header may include a destination / destination port and a source port required for transmission / reception for interactive packet transmission. The B type header may include destination and destination port information required for transmission for non-interactive packet transmission. The fields / information included in the header are as follows.

Destination Port: The destination port identifies a facility entity corresponding to the destination of the data (BTP-PDU) contained in the BTP packet.

Source Port: A field created in the case of the BTP-A type, indicating the port of the protocol entity of the facility layer at the source from which the packet is transmitted. This field may have a size of 16 bits.

Destination Port Info: This field is created for the BTP-B type. It can provide additional information if the destination port is the best known port. This field may have a size of 16 bits.

A geonetworking packet includes a basic header and a common header according to a protocol of a network layer, and optionally includes an extension header according to a geo networking mode. The geo-networking header is described below again.

An LLC header is added to the geo-networking packet to generate an LLC packet. The LLC header provides a function to distinguish and transmit IP data from geo-networking data. IP data and geo-networking data can be distinguished by SNAP's Ethertype. As an embodiment, when IP data is transmitted, the Ether type may be set to 0x86DD and included in the LLC header. As an embodiment, if geo-networking data is transmitted, the Ether type may be set to 0x86DC and included in the LLC header. The receiver can identify the Ethertype field of the LLC packet header and forward and process the packet to the IP data path or the geo networking path according to the value.

3 (a) shows the basic header of the geo-networking packet header shown in Fig. 2, and Fig. 3 (b) shows the common header of the geo-networking packet header shown in Fig.

The basic header can be 32 bits (4 bytes). The basic header may include at least one of a version field, an NH field (Next Header), a LT (LifeTime) field, and a Remaining Hop Limit (RHL) field. Fields included in the basic header are described below. The bit size constituting each field is only an embodiment and may be changed.

Version (4-bit): The version field indicates the version of the geo-networking protocol.

NH (4 bits): NH (Next Header) field indicates the type of the following header / field. If the field value is 1, a common header is followed. If the field value is 2, a secured packet can be followed.

LT (8 bits): The LT (LifeTime) field indicates the maximum lifetime of the packet.

RHL (8 bits): The Remaining Hop Limit (RHL) field indicates the residual hop limit. The RHL field value can be reduced by one for each forwarding on the GeoAdhoc router. When the RHL field value reaches 0, the packet is no longer forwarded.

The common header can be 64 bits (8 bytes). The common header includes a Next Header (NH) field, an HT (HeaderType) field, a HST (Header Sub-Type) field, a TC (Traffic Class) field, a Flags field, a PayloadLength Or the like. The description of each field is as follows.

NH (4 bits): NH (Next Header) field indicates the type of the following header / field. If the field value is 0, it indicates an undefined "ANY" type, 1 indicates a BTP-A type packet, 2 indicates a BTP-B type packet, and 3 indicates an IP diagram of IPv6.

HT (4 bits): The header type field indicates the geo-networking type. Geo-networking types include Beacon, GeoUnicast, GeoAnycast, GeoBroadcast, Topologically-Scoped Broadcast (TSB), and Location Service (LS).

HST (4 bits): The header subtype field indicates the header type as well as the detailed type. As an example, when the HT type is set to TSB, a single hop is indicated when the HST value is '0', and a multi-hop can be designated when the HST value is '1'.

TC (8 bits): The traffic class field may include Store-Carry-Forward (SCF), Channel Offload (Channel Offload), and TC ID. The SCF field indicates whether to store the packet if there is no neighbor to which to transmit the packet. The channel offload field indicates that a packet can be delivered to another channel in the case of a multi-channel operation. The TC ID field is a value assigned at the time of packet forwarding in the facility layer and can be used to set the contention window value at the physical layer.

Flag (8 bits): The flag field indicates whether the ITS device is mobile or stationary, and may be the last one bit as an example.

PL (8 bits): The payload length field indicates the length of data, in bytes, following the geo-networking header. For example, in the case of a geo-networking packet carrying a CAM, the PL field may indicate the length of the BTP header and the CAM.

MHL (8 bits): The Maximum Hop Limit (MHL) field can indicate the maximum number of hops.

The geo-networking header includes the above-described basic header, common header, and extended header. The configuration of the extension header differs depending on the geo-networking type. Hereinafter, a header configuration according to each geo networking type will be described.

In this specification, a V2X communication device that performs geo-networking may be referred to as a router or a geo ad-hoc router. A V2X communication device that transmits geo-networking packets may be referred to as a source router or a sender. A V2X communication device that receives and forwards a geo-networking packet from a source router to a sander can be referred to as a forwarding router or forwarder. The V2X communication device, which is the final destination of the geo-networking packet, or the V2X communication device of the final destination area, may be referred to as a destination or destination router.

4 (a) shows a GUC (Geographically-Scoped Unicast) type data transmission method, and FIG. 4 (b) shows a GUC header structure.

GUC is a method of transferring data from a specific source router to a destination router. As shown in FIG. 4 (a), the source router S can transmit data to the destination router N8 via the multi-hop in the GUC type. The source router must have information about the destination router in its location table. If there is no information about the destination router, the source router can use the "LS request and LS reply" procedures to find the desired destination.

4 (b), the GUC packet header includes a basic header, a common header, and an extension header. The HT field of the common header indicates GUC, and the extension header includes an SN field, an SO PV (Source Position Vector) field, and a DE PV (Destination Position Vector) field. The description of the included fields is as follows.

SN (Sequence Number): The sequence number field indicates a value used for checking packet redundancy. The value of the sequence number field is incremented by one when transmitting packets from the source. In the receiving router, it is possible to determine whether or not to receive a packet by using a sequence number (or a sequence number and a TST value). SN is the value used for multi-hop transmission.

SO PV: Indicates the position of the source and can be a long position vector format.

DE PV: Indicates the location of the destination and can be a short position vector format.

5 (a) shows a TSB (Topologically Scoped Broadcast) type data transmission method, and Fig. 5 (b) shows a TSB header configuration.

The TSB is a broadcast scheme that adjusts the distance that data is transmitted by the number of hops. Location-based information is not used. Since the number of hops only determines the delivery of data, the location address of the destination or the area information to which the data is delivered is not used. Data can be forwarded from the source router (s) to all routers in the n-hop.

5 (a) shows data transmission of the TSB scheme of n-2. The source router broadcasts the signal by setting n = 2, and the routers within the transmission range of the source router receive this signal. Since N = 2, the forwarding routers N1, N2, and N3 receiving the data in one hop re-broadcast the received packet. Since N = 2, the routers receiving the re-broadcast signal do not re-broadcast the received packet. In this TSB transmission method, a single hop (n = 1) can be referred to as a single hop broadcast (SHB).

5 (b), the TSB packet header includes a basic header, a common header, and an extension header. The HT field of the common header indicates the TSB, and the extension header includes an SN field and an SO PV (Source Position Vector) field. The description of the included fields is as follows.

In the case of the TSB header, the number of transmissions is limited by the number of hops, so the destination address may be omitted.

FIG. 6A shows a data transmission method of SHB (Single Hop Broadcast) type, and FIG. 5B shows a SHB header configuration.

The SHB corresponds to a case in which the number of hops is 1 (n = 1) in the TSB described above. SHB packets are transmitted only to routers within the source router transmission range. Since data can be transmitted with the lowest latency, the SHB can be used for transmission of security messages such as CAM. Packets are transmitted only to the one-hop range routers N1, N2 and N3 of the source S as shown in FIG. 6 (a).

6 (b), the SHB packet header includes a basic header, a common header, and an extension header. The HT field of the common header points to the TSB, and the extension header contains an SO PV (Source Position Vector) field. The description of the included fields is as follows.

In case of SHB packet, the destination address can be omitted because the number of times of transmission is limited by the number of hops. Since the multi-hop transmission is not performed, the SN field for redundancy check can also be omitted.

FIG. 7A shows a GBC (Geographically-Scope Broadcast) / GAC (Geographically-Scoped Anycast) type data transmission method, and FIG. 4B shows a GBC / GAC header configuration.

GeoBroadcast / GBC is a transmission method that broadcasts packets to all routers in a certain area. GeoAnycast / GAC transmits packets only to one router that receives the first packet in a specific area. Transmission method. In the GBC, when the data transferred from the source router is delivered to a specific destination area, the packet is broadcast in a predetermined area. In the GAC, when a packet is delivered to one router in a specific destination area, the packet is no longer transmitted.

7 (b), the GBC / GAC header includes a basic header, a common header, and an extension header. The HT field of the common header indicates the GBC or the GAC, and the extension header includes an SN field, an SO PV (Source Position Vector) field, and destination area information. The destination area information includes a GeoAreaPosLatitude field, a GeoAreaPosLongitude field and a distance field (Distance a, b) and an angle field for indicating a range of the area.

8 shows a header configuration of a beacon packet. The beacon packet header includes a basic header, a common header, and an extension header, and the extension header may include SO PV information.

The beacon packet may be configured similar to the SHB packet header described above. The difference is that the SHB packet is used to carry data such as a CAM after which a message can be appended, and a beacon is used for the header itself without data being appended. CAM using SHB or beacon can be transmitted periodically. By transmitting and receiving the CAM or the beacon, the router obtains the location information of neighboring routers, and can perform routing using this location information. As an example, if the CAM is transmitted, the beacon may not be transmitted.

Fig. 9 (a) shows the LS request packet header, and Fig. 9 (b) shows the LS response packet header.

If there is no destination information in its location table, the source router can request geo-networking address information (GN_ADDR) for the destination in the vicinity. This address information request can be performed by transmitting an LS request packet (LS request) to the LS request packet. If the location table of the router receiving the LS request packet contains the information requested by the source router, the router can transmit LS response information (LS_reply). In addition, the router at the destination can transmit the LS response information to the LS request information.

The LS response information includes position vector information of GN_ADDR. The source router may update the location table via the LS response information. The source router can perform the GUC transmission by using the received geo-networking address information in response.

9 (a), the configuration of the LS request packet header is similar to the GUC header. In the LS request packet header, a geo networking address request field (RequestGN_ADDR) is included in place of the destination address field of the GUC header.

9 (b), the LS response packet header configuration is the same as the GUC packet header. However, the SO PV field includes the position vector information of the router, and the DE PV field includes the position vector information of the router that transmitted the request.

As described above, the geo-networking packet header includes a position vector (PV) field associated with a location. The types of position vectors include long PV and short PV. 10 (a) shows long position vector information, and FIG. 10 (b) shows short position vector information.

As shown in FIG. 10 (a), the long position vector information includes the following subfields.

GN_ADDR: The geo-networking address field can consist of a total of 64 bits. A geo ad-hoc router with geo-networking transport has a unique geo-networking address value. The geo-networking address field may include the following sub-fields.

a) M: Field to distinguish between geo networking address and manually set value. As an example, if the value is '1', it may be a manually set value.

b) ST: The ITS-S type field indicates the type of ITS station. The ITS-S type can be used for pedestrians, bicycle cyclists, mopeds, motorcycles, passenger cars, buses, light trucks, heavy trucks, trailers, special vehicles, , Trams, RSUs.

c) MID: As the V2X device identification information, the MAC address can be used.

TST (TimeSTamp): The Type Stamp field indicates the time at which the ITS station obtained the latitude / longitude value on the geo ad-hoc router. As a millisecond unit, a Universal Time Coordinated (UTC) value may be used.

LAT (Latitude), Long (Longitude): The latitude and longitude fields indicate latitude and longitude values of the geo ad-hoc routers.

PAI (Position Accuracy Indicator): Indicates the accuracy of geo ad-hoc router location.

S (Speed): Indicates the speed of the geo ad-hoc router.

H (Heading): Indicates the direction of the geo ad hoc router.

10 (b), the short position vector information includes a GN_ADDR field, a TST field, a LAT field, and a Long field. The description of each field is as described above for the long position vector.

Various packet forwarding methods can be used for geo-networking transport. For example, a greedy forwarding algorithm, a contention-based forwarding algorithm, a non-area contention-based forwarding algorithm, an area contention-based forwarding algorithm, an area advanced forwarding Algorithm or the like may be used. The forwarding algorithm is used to effectively transfer and distribute the data to the desired area. In the case of the greedy forwarding algorithm, the source router determines the forwarding router, and in the case of the contention-based forwarding algorithm, the receiving router determines whether to forward the packet using the contention. In the following, a V2X device / router that processes geo-networking algorithms may be referred to as an ego router.

In geo-networking, each V2X device performs the function of a router and can use an ad hoc method to determine the routing of the packet. Each V2X device transmits location information, speed information, and heading direction information of the vehicle around, and using this information, each V2X device can determine the routing of the packet. The information received periodically is stored in the LocT (Location Table) of the network & transport layer, and the stored information can be timed out after a certain period of time. LocT may be stored in a LocTE (Location Table Entry).

For geo-networking protocol operation, each ad hoc router must have information about the other ad hoc routers. Information about the neighboring routers may be received via SHB or beacon packets. Routers can update LocT when new information is received. The transmission period of the SHB or the beacon packet may be changed according to the channel state. The location / location table may also be referred to as LocT.

Information about the neighboring routers is stored in the LocT, and the stored information may include at least one of the following information. The information stored in the LocT may be deleted from the list when the lifetime set in the soft-state state has expired.

GN_ADDR: Geo-network address of ITS station

Type of ITS-S: Indicates the type of ITS station, for example, vehicle or RSU.

Version: Geo-networking version used for ITS station

Position vector PV: The position vector information includes geographical position information, velocity information, heading information, time stamp information indicating the position information measurement time, position accuracy indicator (PAI) information indicating the accuracy of the position providing information Or the like.

Flag LS_PENDING (LS_PENDING flag): A flag indicating when a location service request is in progress because the current LocT does not have an address for the destination

FLAG IS_NEIGHBOUR (IS_NEIGHBOUR flag): A flag indicating whether there is a geo ad-hoc router capable of communicating within communication range

DPL: Duplicate Packet List for source GN_ADDR

Type Stamp: The time stamp of the last packet indicating the end of duplication

PDR (Packet Data Rate): Packet data rate to be maintained in geo ad hoc routers

The greedy forwarding algorithm determines which of the neighbor routers the sander will know about to forward the packet to. The LocT (Locator Table) of the sander can be updated to the latest value through a periodically distributed SHB or beacon packet. The sander selects the router closest to the destination from the LocT, which allows the packet to be delivered to the destination with the least number of hops.

11, routers 1 to 5 exist in the communication range of the source router. The source router transmits the packet by setting the MAC address of the router 2 closest to the destination to the link layer destination address.

The Greedy Forwarding Algorithm does not use buffering, and can forward a packet to its destination as fast as it can without breaking the connection between routers. However, if the connection between the routers is lost, that is, if the router to which the next hop is to be transmitted deviates from the transmission range or disappears, the reliability of the packet can not be transmitted.

Hereinafter, a packet delivery method of a contention-based forwarding algorithm will be described.

The contention-based forwarding algorithm determines, by contention, whether the receiver will forward the packet, unlike the greedy forwarding algorithm described above. Any receiver that receives a packet broadcast by the sander can be a potential forwarder. The receiver sets its own timer according to the distance, and the receiver whose timer has expired first forwards the packet. If the receiver does not receive a packet from other receivers until the timer expires, the receiver forwards the packet when the timer expires. If a packet is received before the timer expires, the receiver will turn its timer off and will not forward the packet.

Contention-based forwarding algorithms do not need to know the location of neighboring routers, unlike the greedy forwarding algorithm. The packet forwarding can be performed even if the SHB packet or the beacon packet is not periodically transmitted, i.e., the location table is not present. Since there are a plurality of candidate forwarders, the reliability may be high and the probability of delivering packets to the destination may be high. However, buffering time is required for packet delivery and latency may increase. In addition, additional buffer usage is required.

Non-area contention-based algorithms are used to deliver packets in the destination direction. In Fig. 12, the source router S may broadcast packets for packet transmission. Routers (1 to 5) within the communication range of the source router receive the packet. Of routers, only the router closest to the destination can be a forwarding candidate. In Fig. 12, the routers 1-3 can be forwarder candidates.

Forwarder candidates can store the received packet in a Contention-based Forwarding (CBF) packet buffer and set a timer. The timer can be set to a smaller value as the distance from the source increases. In Fig. 11, the timer of the router 1 can be set to 25 ms, the timer of the router 2 to 10 ms, and the timer of the router 3 to 20 ms, respectively. When the timer expires, the router broadcasts the buffered packet.

Router 2, whose timer expires first, broadcasts the packet. Router 1 and Router 3, which have received the packet broadcasted by Router 2, stop their timer and delete the packet stored in the buffer. However, if Router 2 disappears or if Router 1 and Router 3 do not exist within the communication range of Router 2, the timers of Router 1 and Router 3 are still valid, and thus the router that broadcasts the packet first becomes a timer of 0.

The area contention-based forwarding algorithm aims at efficiently spreading data in a certain area. Therefore, there is no fixed destination and the timer setting can be determined only considering the distance from the source. The area contention based algorithm is performed when the router belongs to a specific area, and it is aimed at rapidly distributing / transmitting information within the area.

In Fig. 13, a packet broadcasted by the source router S is transmitted to the routers 1 to 6. Router 2, which is farthest from the source router, broadcasts the packet first, and Router 1 and Router 3, which receive it, stop the timer and do not forward the same packet.

Routers

4 and 6 do not receive packets forwarded by router 2. Therefore, routers 4 to 6 operate their respective timers and broadcast received packets when the timer expires. When the router 5 forwards the packet, the router 4 that has received the packet ends its timer and removes the packet being prepared for transmission from the buffer. Router 6, which has not received the packet forwarded by another router, forwards the packet when its timer expires. In the case of the area contention-based algorithm, the source router can quickly forward and share packets in a certain area in all directions.

In addition to the embodiments of Figures 12 and 13, an area advanced forwarding algorithm may be used. The area advanced forwarding algorithm is an algorithm that operates by combining the above-described greedy forwarding algorithm and contention-based forwarding algorithm. Area advanced forwarding algorithms, such as contention-based forwarding algorithms, use packet-forwarding algorithms to route packets in certain directions to minimize delays, while contention-based forwarding methods are used to increase delivery efficiency .

A forwarding algorithm that delivers packets to a specific destination area is called a non-area algorithm. Non-region algorithms include greedy forwarding algorithms and non-area contention-based forwarding algorithms. An algorithm for distributing data around a specific area is called an area-forwarding algorithm. The area-forwarding algorithm includes a simple geo-broadcast forwarding algorithm, an area contention-based forwarding algorithm, and an area advanced forwarding algorithm.

Fig. 14 (a) shows the US spectrum allocation for the ITS, and Fig. 14 (b) shows the EP spectrum allocation for the ITS.

In FIG. 14, the United States and Europe have seven frequencies (each frequency bandwidth: 10 MHz) in the 5.9 GHz band (5.855 to 5.925 GHz). The seven frequencies may include one Control Channel (CCH) and six Service Channels (SCH). As shown in FIG. 14A, the CCH may be allocated to the channel number 178 in the US, and the CCH may be allocated to the channel number 180 in the European case, as shown in FIG. 14B.

In Europe, the use of the ITS-G63 band is considered in addition to the upper frequency band based on 5.9 GHz for the provision of time-sensitive and data-rich services, and the use of the ITS- Use is being considered. In this environment, it is necessary to develop an efficient multi-channel operation scheme in order to provide high-quality services by appropriately allocating services to various multi-channels.

The control channel (CCH) represents a radio channel used for management frame and / or WAVE message exchange. A WAVE message can be a WSM (WAVE short message). A service channel (SCH) is a radio channel used for service provision, and represents any channel other than a control channel. As an example, the control channel may be used for communication of a Wave Short Message Protocol (WSMP) message or a system management message such as WAVE Service Advertisement (WSA). SCH can be used for general-purpose application data communication, and the communication of such general-purpose application data can be coordinated by service-related information such as WSA.

The WSA may be referred to as service propagation information below. The WSA may provide information including an announcement of the availability of the application-service. A WSA message may identify and describe a channel that is accessible to application services and services. As an example, the WSA may include a header, service information, channel information, and WAVE routing advertisement information.

The service advertisement information for the service connection may be a periodic message. As an example, Co-operative Awareness Messages (CAM) may be periodic messages. CAMs can be periodically broadcasted by the facility layer.

Decentralized Environmental Notification Messages (DENM) can be event messages. The event message can be triggered and transmitted by detection of an event. A service message may be sent to manage the session. In the following embodiments, the event message may include the safety message / information. And the service message may include non-secure message / information.

The V2X communication device can broadcast a Cooperative Awareness Message (CAM) or a Decentralized Enviriomental Notification Message (DENM).

The CAM is distributed in the ITS network and provides information about at least one of the presence, location or communication status of the ITS station. DENM provides information about detected events. The DENM may provide information about any driving situation or event detected by the ITS station. For example, DENM can provide information on situations such as emergency electronic brakes, vehicle accidents, vehicle problems, traffic conditions, and so on.

## The geo-networking technology described above is a technology that can extend the V2V or V2I communication connectivity between ITS stations and support various service scenarios that can be derived on future collaborative intelligent transportation system (C-ITS). However, due to the limitation of ad-hoc communication between mobile stations, high connection reliability may not always be guaranteed.

The relative position and distribution of an ITS station (e.g., a Vehicle ITS Station (VIS) or a Roadside ITS Station (RIS)) at every moment in the process of forwarding a packet to a multi-hop may be dynamically changed . Therefore, a forwarder that receives a packet at a particular hop can not always be guaranteed the possibility of finding the next best forwarder to receive the packet to the next hop. This is true even if the fixed RIS is included as a forwarder of the multi-hop packet transmission. This is because the transmission between the hops is relative, so the same phenomenon occurs in transmission from a dynamic VIS to a fixed RIS. Therefore, it is necessary to consider a method of reducing the number of transmissions between hops and delivering multi-hop packets through a connection between the more reliable ITS stations. In other words, there is a need to consider new methods of geo-networking.

Hereinafter, a geo-networking method using an infrastructure network will be described. Specifically, a method for efficiently transmitting a geo-networking packet using I2I communication between infrastructures will be described. Using this method increases the probability of delivering multi-hop packets and reduces the propagation delay time as compared to the geo-networking method using only V2V communication between vehicles.

In this specification, the ITS station may be referred to as a V2X communication device, the VIS as a vehicle V2X communication device or OBU, and the RIS as a roadside V2X communication device or RSU.

FIG. 15 illustrates a geo-networking packet forwarding method of an ITS station according to an embodiment of the present invention. The geo-networking packet forwarding method of the embodiment of FIG. 15 corresponds to a method in which the RIS can be used as a forwarder of the geo-networking packet forwarding method, but does not utilize I2I communication between the infrastructures for packet forwarding.

In the embodiment of FIG. 15, it is assumed that the geo-networking type is geo-broadcast, geo-ani-cast or geo-unicast. It is also assumed in the embodiment of FIG. 15 that a greedy forwarding algorithm (GFA) is used as the forwarding algorithm. However, this is merely to simplify and show the packet delivery process. Therefore, the same or similar description can be applied even when using a contention-based forwarding algorithm (CBFA), except that a plurality of ITS stations within each communication range can participate as a forwarder every hop.

Referring to FIG. 15, a packet originated from a source station (sander) may be finally transmitted to a destination station (destination) via a forwarding station (forwarder). As described above, in the case of geo-broadcast, all the stations in a specific geo-location area can be designated as destinations, and in the case of geo-anycast, any one station existing on a specific geo-location is designated as a destination In the case of geo unicast, a specific station can be designated as a destination based on the geo-address stored in the source station.

In the embodiment of FIG. 15, the ITS station may be a VIS or a RIS, and each ITS station may have a range of communication in a range indicated by a dotted circle. As an example, adjacent ITS stations may have the same communication range due to ITS-G5 congestion control.

In the case of VIS with mobility, the distribution position can change dynamically over time. In this situation, as shown, the packets originating from the source station are forwarding station # 1 -> forwarding station # 2 -> ... -> Forwarding Station #n -> Forwarding Station # n + 1 -> Forwarding Station # n + 2. At this time, the forwarding station receiving the packet must determine the forwarding station to be the next forwarder within its communication range. The next forwarding station thus determined may be a VIS or RIS.

As described above, it is anticipated that as the movement of each station is dynamic and the number of forwarders participating in the packet delivery process decreases, the possibility of the packet being delivered to the final destination through geo-networking forwarding (method) may be lowered.

On the other hand, in the geo-networking method based on the ITS-G5 access technology as in the embodiment of FIG. 15, the RIS participating as a forwarder has a transmission power (transmission range) similar to that of the VIS. In addition, since the packet is transmitted through competition with another VIS or RIS through the CSMA / CA rule, the transmission efficiency when the RIS participates is the same as that when only the VIS is configured. The reason why RIS maintains the same transmission range and transmission efficiency as VIS is that all the participating stations have the same communication opportunity in ad-hoc communication can maximize the transmission efficiency under DCC (decentralized congestion control). However, the role of the infrastructure within the entire C-ITS network may be effective. This will be described with reference to FIG.

16 illustrates a method for delivering an ITS message using an infrastructure in a C-ITS according to an embodiment of the present invention. The ITS message / packet forwarding method of the embodiment of FIG. 16 corresponds to a method in which an infrastructure network is used for delivery of a packet but a packet must be delivered via a central ITS station (CIS).

In the embodiment of FIG. 16, the ITS message may be a traffic safety related message (e.g., a traffic accident message). For example, when a traffic accident occurs, a sensing station that detects a traffic accident for the first time can notify traffic accidents by transmitting a traffic accident occurrence message (Msg # 1) to nearby stations. As an example, the traffic accident occurrence message may be in the form of a DENM message.

Adjacent RIS # 1 can forward Msg # 1 to a central ITS station (CIS) that performs centralized traffic control through the backbone network, i.e., the infrastructure network. The CIS can collectively analyze various traffic information received through Msg # 1 and various routes and transmit Msg # 2 such as a traffic signal control message or a guidance message to an area where appropriate control or guidance is required. In this process, the CIS can deliver this Msg # 2 to RIS # 2 in a specific area. The RIS # 2 having received the Msg # 2 can transmit the Msg # 2 to the neighboring VIS.

In this case, an ITS-G5-based geo-networking packet can be used for the connection between the sensing station and the RIS # 1 and the connection between the RIS # 2 and the destination station. However, since the connection between RIS # 2 and CIS and the connection between CIS and RIS # 2 are transmission processes through the infrastructure network, a dedicated protocol based on IP (e.g., IPv6) can be used. As such, RISs can act as appropriate gateways for ITS-G5 and infrastructure network connections.

Thus, according to the method of the embodiment of FIG. 16, the number of transmission hops of a packet / message can be reduced compared to the method of the embodiment of FIG. 15 which does not use an infrastructure network. However, in the method of the embodiment of FIG. 16, because the message is transmitted via the CIS, the message of the sender is not transmitted to the destination as it is due to the processing in the CIS, and the transmission time is also delayed. Therefore, there is a need for a new type of geo-networking packet delivery method that utilizes I2I communication between infrastructures that do not go through a CIS for packet delivery.

FIG. 17 shows a protocol stack of an ITS station for an ITS message delivery method using the infrastructure of FIG. 16; Specifically, FIG. 17 is a diagram illustrating a method of transmitting an ITS message using the infrastructure of FIG. 16 in terms of a protocol stack. In the embodiment of FIG. 17, the access layer indicated in the RIS block may be an access layer using various access technologies such as Ethernet, Coaxial, and Optical fiber.

Referring to FIG. 17, the sensing station may transmit an ITS-G5 packet including an Msg # 1 (DENM message) through an ITS-G5 network.

The RIS # 1 receiving this packet can parse this packet and generate a first I2I packet including Msg # 1 using an I2I protocol suitable for a pre-configured infrastructure network. At this time, the application of RIS # 1 may cause the format of Msg # 1 to be changed to a format suitable for the first I2I packet. The first I2I packet thus generated can be transferred to the CIS through the infrastructure network.

As an example, the I2I protocol may be an IP-based I2I protocol (e.g., TCP / IP protocol). As an example, the upper protocol stack on the TCP / IP protocol may be XML-based DATEX II in progress to the I2I standard in Europe.

The CIS that received the first I2I packet parses the packet and performs a comprehensive determination based on the data received through the various paths to include a Msg # 2 such as a control or guide message provided in a specific area A second I2I packet can be generated. The generated second I2I packet can be transmitted to the RIS # 2 through the infrastructure network. At this time, an IP-based I2I protocol can be used.

The RIS # 2 receiving the second I2I packet can parse this packet and generate an ITS-G5 packet including Msg # 2 using a protocol suitable for the ITS-G5 network. At this time, the application of RIS # 2 can cause the format of Msg # 2 to be changed to a format suitable for the ITS-G5 packet. The ITS-G5 packet thus generated can be delivered to the destination via the ITS-G5 network.

## The following explains how to use an infrastructure network that does not go through CIS to increase the efficiency of multi-hop packet delivery using V2V communication. To this end, as in the embodiment of FIG. 17, there is a need to consider a message delivery scheme capable of achieving a low latency and also being able to be transmitted between networks in which a heterogeneous upper protocol stack is supported. The geo-networking packet forwarding method described below with reference to the respective figures corresponds to a new method of geo-networking packet forwarding method that uses I2I communication between infrastructures that do not go through CIS for forwarding of packets.

18 illustrates a method of transmitting a geo-networking packet using an infrastructure network according to an embodiment of the present invention. Specifically, FIG. 18 shows a first embodiment of a geo-networking method using I2I communication between RISs. On the other hand, in the embodiment of FIG. 18, it is assumed that the forwarding algorithm for V2V forwarding or V2I / I2V forwarding is GFA.

A station participating in geo-networking can recognize a station that can participate in geo-networking forwarding around the geo-beacon (beacon packet) received in the vicinity. When a message generated by an application of a source station is intended to be delivered to a destination via a multi-hop, the source station may select a method of using the RIS as a forwarder of the message as a geo-networking method.

In the embodiment of FIG. 18, since the GFA is used as the forwarding algorithm, the next forwarder may be selected every hop to transmit the message. Therefore, only the forwarder selected in the particular hop can forward the message by selecting the forwarder (next forwarder) of the next hop. At this time, the forwarder can determine whether there is an RIS capable of forwarding through I2I communication (i.e., RIS capable of I2I forwarding) within its communication range. If the RIS is present, the forwarder can forward the message by selecting the RIS as the next forwarder. For example, as shown, forwarding station # 1 selected by the source station may select forwarding station # 2, which is an RIS capable of I2I forwarding, as the next forwarder.

When the RIS (first RIS) selected as the forwarder receives the message, one of the RISs capable of communicating with the first RIS and I2I can be selected as the next forwarder without selecting the next forwarder in the ITS-G5 channel (network) . As an example, the first RIS may find the nearest RIS (second RIS) on the geo-location of the destination and may select it as the next forwarder. Thereafter, the first RIS may transmit the message to the second RIS through the I2I communication. For example, as shown, forwarding station # 2 may select forwarding station # 3, which is the nearest RIS on the destination and geo-location, as the next forwarder and may forward the message to forwarding station # 3 via I2I communication.

If the RIS (the second RIS) adjacent to the destination receives the message, this message can be geo-networked forward to the destination again via the ITS-G5 channel. For example, as shown, this message may be geo-networked forwarded to the destination via forwarding station # 4 and forwarding station # 5, which are VIS.

As described above, in the geo-networking method using the I2I communication between the RISs (I2I forwarding), geo-networking packets can be transmitted to the destination with a smaller number of hops than the geo-networking method using only the V2V communication (V2V forwarding) between the VISs. This can increase the likelihood of destination transmission of geo-networking packets and reduce propagation delay time.

FIG. 19 illustrates a method of transmitting a geo-networking packet using an infrastructure network according to another embodiment of the present invention. Specifically, FIG. 19 shows an example of a second embodiment of a geo-networking method using I2I communication between RISs. In the embodiment of FIG. 19, it is assumed that the forwarding algorithm for V2V forwarding or V2I / I2V forwarding is CBFA. In FIG. 19, the description overlapping with the above description in FIG. 18 is omitted.

In the embodiment of FIG. 19, since the CBFA is used as the forwarding algorithm, all the stations in the communication range can perform the role of the next forwarder without designating the next forwarder every hop. Accordingly, when a RIS (first RIS) capable of I2I forwarding at a specific hop receives a message, the first RIS voluntarily transmits one of the RISs capable of I2I communication without transmitting a message to the ITS- It can be selected as a forwarder. As an example, the first RIS may find the nearest RIS (second RIS) on the geo-location of the destination and may select it as the next forwarder. Thereafter, the first RIS may transmit the message to the second RIS through the I2I communication. For example, as shown, forwarding station # 1 (forwarding RIS station # 1) may select forwarding station # 3 (forwarding RIS station # 3), which is the closest RIS on the destination and geo-location, as the next forwarder, The message can be transmitted to the forwarding RIS station # 3 through communication.

However, in this case, due to the characteristics of the CBFA, there may be a plurality of RISs participating in I2I forwarding. For example, as shown, forwarding station # 2 (forwarding RIS station # 2) may join I2I forwarding with forwarding RIS station # 1. In this case, like the forwarding RIS station # 1, the forwarding RIS station # 2 can select the forwarding RIS station # 3 as the next forwarder, and can transmit the message to the forwarding RIS station # 3 through the I2I communication.

At this time, each RIS capable of I2I forwarding can receive the same message from several VISs. In this case, each RIS can forward only the first received message of the same message to the RIS acting as a next forwarder. For example, as shown, the forwarding RIS station # 1 receiving the same message from the three forwarding stations VIS can forward only the first received message to the forwarding RIS station # 3.

On the other hand, an RIS that receives a message over an infrastructure network can also receive the same message from multiple RISs. In this case, the RIS can forward only the first message received from the same message to the VIS acting as a next forwarder. For example, as shown, a first message transmitted through the I2I path # 1 from the forwarding RIS station # 1 and a second message transmitted through the I2I path # 2 from the forwarding RIS station # The RIS station # 3 can forward only the first received message to the forwarding station (VIS). At this time, the first message and the second message are the same message. In this case, the remainder of the delayed message may be discarded.

This message can then be geo-networked forwarded to the destination over the ITS-G5 channel again. For example, as shown, this message may be geo-networked forwarded to the destination via forwarding stations (VIS) around the forwarding station # 3.

20 shows a structure of a geo-networking header according to an embodiment of the present invention. FIG. 20A shows an exemplary structure of a geo-networking packet (or ITS-G5 packet), FIG. 20B shows an exemplary structure of a geo-networking header, Shown is an exemplary structure of a common header. In Fig. 20, a description overlapping with the above description in Fig. 3 will be omitted.

Referring to FIG. 20 (b), the geo-networking header may include a basic header, a common header, and / or an extension header. Referring to FIG. 20 (c), the common header may further include an I2I forwarding related signaling field to provide a geo-networking method using I2I forwarding, in addition to the fields described in FIG. 3 (b).

The common header can be used to determine the geo-networking type. That is, the common header may include a field (e.g., an HT field) used to determine the geo networking type. As described above, in a geo-networking type (geo-networking mode), a type that operates based on a clear destination, such as geo-broadcast, geo-ani-cast or geo unicast, supports I2I forwarding for efficient geo-networking packet delivery It is important. Therefore, for this purpose, I2I forwarding related signaling information needs to be inserted on the geo-networking header. For example, as shown in FIG. 20 (c), I2I forwarding-related signaling information may be included in a common header in the geo-networking header.

This I2I forwarding related signaling field is a signaling field that must be included on the geo-networking header in order to use I2I forwarding for geo-networking. In this specification, an I2I forwarding related signaling field may be referred to as an I2I signaling field.

As an example, the I2I forwarding related signaling information / field may be included in the 4-bit reserved field (bit) and / or the 8-bit reserved field (bit) of the common header, as shown in Fig. 20 (c). In this case, the I2I forwarding related signaling field included in the 4-bit reserved field may be referred to as a first I2I signaling field (I2I signaling # 1), and the I2I forwarding related signaling field included in the 8- May be referred to as an I2I signaling field (I2I signaling # 2).

Figure 21 shows a first I2I signaling field according to an embodiment of the present invention. As described above, the first I2I signaling field may be included in the common header using the 4-bit reserved bits of the common header.

Referring to FIG. 21, the first I2I signaling field may include an I2I priority field (I2I priority), an I2I lifetime type field (Type of I2I life-time), and / or an I2I capability field . Each field will be described below.

The I2I priority field may indicate whether I2I forwarding is prioritized. That is, it can indicate that I2I forwarding has priority. Here, I2I forwarding refers to the forwarding of packets / messages through I2I communication, as described above.

As an example, the I2I priority field may be a one-bit flag field indicating whether I2I forwarding has priority. For example, if the I2I priority field is set to a first value (e.g., 0), the I2I priority field may indicate that I2I forwarding has no priority (no priority). Alternatively, if the I2I preference field is set to a second value (e.g., 1), the I2I priority field may indicate that I2I forwarding has priority. As such, when the neighbor forwarder (VIS) recognizes the RIS capable of I2I forwarding or the RIS capable of I2I forwarding receives the geo-networking packet including this field, the I2I priority field gives priority to the I2I forwarding operation through the RIS To be selected.

The I2I lifetime type field may indicate the type of I2I lifetime. As an example, the I2I lifetime type field may be a 1-bit field indicating the type of I2I lifetime. In the present specification, the I2I lifetime type field may be referred to as a lifetime type field.

For example, if the I2I lifetime type field is set to a first value (e.g., 0), the I2I lifetime type field may indicate that the type of I2I lifetime is maximum time. That is, the I2I lifetime can be indicated by the maximum time or the maximum allowable time. In this case, the geo-networking packet is valid only for the maximum amount of time that is allowed before being forwarded to the RIS for I2I forwarding.

Alternatively, if the I2I lifetime type field is set to a second value (e.g., 1), the I2I lifetime type field may indicate that the type of I2I lifetime is the remaining number of hops. The I2I lifetime can be dictated by the number of hops remaining. In this case, the geo-networking packet is only valid for the number of remaining hops before being forwarded to the RIS for I2I forwarding. That is, if the predetermined maximum time has elapsed before being transmitted to the RIS for I2I forwarding, the lifetime of the geo-networking packet expires.

This I2I lifetime type field is a field that affects the field definition of the second I2I signaling field to be described later, and can be used to confirm I2I validity with the second I2I signaling field. As such, the I2I lifetime type field may be used to determine the content of the second I2I signaling field. For example, the I2I lifetime type field and the second I2I signaling field of the first I2I signaling field may indicate the number of valid hops or the validity time until the geo-networking packet is delivered to the RIS capable of I2I forwarding. This can prevent channel flooding due to the addition of the I2I forwarding function. That is, if there is no remaining hop count before the RIS is forwarded for I2I forwarding, the lifetime of the geo-networking packet expires.

The I2I capability field may indicate the I2I forwarding capability of the RIS. In particular, the I2I capability field may indicate whether the RIS transmitting the geo-networking packet has an I2I forwarding function.

As an example, the I2I capability field may be associated with the Flags field of the common header. As described above, the flag field may indicate whether the ITS station is mobile or stationary. For example, the flag field may indicate whether the ITS station is RIS or VIS. If this flag field indicates that the ITS station is a RIS, the common header may include an I2I capability field and indicate the I2I forwarding capability of that RIS via this I2I capability field.

As an example, the I2I capability field may be a 2-bit field indicating the I2I forwarding capability of the RIS that transmits the geo-networking packet. For example, if the I2I Capability field is set to a first value (e.g., 00), the I2I Capability field may indicate that the RIS transmitting the geo-networking packet does not have I2I forwarding capability. That is, if the I2I capability field is the first value, the I2I Capability field may indicate that this RIS is not capable of I2I forwarding.

Alternatively, if the I2I capability field is set to a second value (e.g., 01), then the I2I capability field indicates that the RIS that is transmitting the geo-networking packet is capable of I2I forwarding but does not have a proximity list . That is, when the I2I capability field is the second value, the I2I capability field indicates that the corresponding RIS can perform I2I forwarding but does not include surrounding RIS list information capable of I2I forwarding on the geo-networking packet (for example, beacon packet) Can be indicated.

Alternatively, if the I2I capability field is set to a third value (e.g., 10), then the I2I capability field indicates that the RIS transmitting the geo-networking packet is capable of I2I forwarding and that there is a proximity list . That is, when the I2I capability field is the third value, the I2I capability field indicates that the RIS includes surrounding RIS list information capable of I2I forwarding and capable of I2I forwarding on the geo-networking packet (for example, beacon packet) You can tell. The case where the peripheral RIS list information is included in the beacon packet will be described below with reference to FIGS. 23 and 24. FIG.

Alternatively, if the I2I capability field is set to a fourth value (e.g., 11), the I2I capability field may indicate that the RIS transmitting the geo-networking packet has I2I forwarding capability through cellular handover. That is, if the I2I capability field is a fourth value, the I2I capability field may indicate that this RIS is capable of I2I forwarding via cellular handover. I2I forwarding via cellular handover is described in detail in Fig.

22 shows a second I2I signaling field according to an embodiment of the present invention. As described above, the second I2I signaling field may be included in the common header using the 8-bit reserved bits of the common header.

The second I2I signaling field is defined according to the selection of the I2I lifetime type field of the first I2I signaling field. The second I2I signaling field may indicate a value of I2I lifetime according to the type of I2I lifetime indicated by the I2I lifetime type field. In this specification, the second I2I signaling field may be referred to as an I2I lifetime value field or a lifetime value field. In addition, a field including the lifetime type field and the lifetime value field described above may also be referred to as an I2I lifetime field.

22 (a) shows a second I2I signaling field when the I2I lifetime type field of the first I2I signaling field is a first value (e.g., 0). In this case, the second I2I signaling field may indicate the value of the maximum allowable time that the geo-networking packet can be delivered to the I2I capable RIS. That is, the second I2I signaling field may indicate the maximum available time (maximum time) until the geo-networking packet is delivered to the RIS capable of I2I forwarding. Therefore, if the geo-networking packet is not delivered to the RIS capable of I2I forwarding within the maximum valid time, the I2I lifetime is terminated. The operation according to the end of the I2I lifetime will be described below.

As an example, the second I2I signaling field indicating the maximum time may be an 8-bit field. For example, in this second I2I signaling field, 7 of 8 bits (e.g., MSB 7 bits (bit 0 to bit 6)) can be set as a mantissa to indicate a value from 0 to 127, and 1 A bit (e.g., LSB 1 bit (bit 7)) may be used to indicate a time scale (e.g., 10 ms or 1 s) as an exponent portion. At this time, when the value of LSB 1 bit is a first value (e.g., 0), it is indicated that the time scale is 10 ms, and when the value of LSB 1 bit is a second value (e.g., 1) . For example, when the binary representation of the second I2I signaling field indicating the maximum time is '01000111', the maximum valid time is set to 35s.

22 (b) shows a second I2I signaling field when the I2I lifetime type field of the first I2I signaling field is a second value (e.g., 1). In this case, the second I2I signaling field may indicate the value of the remaining hop count that a geo-networking packet can be delivered to an I2I capable RIS. That is, the second I2I signaling field may indicate the number of remaining hops until the geo-networking packet is delivered to the RIS capable of I2I forwarding. Therefore, if the geo-networking packet is not delivered to the RIS capable of I2I forwarding within the remaining number of hops, the I2I lifetime is terminated. The subsequent operation in accordance with the I2I end of life (failure of I2I forwarding) will be described below.

As an example, the second I2I signaling field indicating the number of remaining hops may be an 8-bit field indicating the remaining hops. In this case, the second I2I signaling field is decremented by one as the hop between ITS stations proceeds, and can not have a value smaller than zero.

The first I2I signaling field and the second I2I signaling field described above correspond to a signaling field necessary for geo-networking packet forwarding via I2I. Thus, if I2I forwarding is not enabled by the I2I priority field of the first I2I signaling field (i.e., I2I forwarding does not have priority), the setting of the remaining signaling fields may be ignored.

On the other hand, if a RIS capable of I2I forwarding is not found within the maximum valid time indicated by the second I2I signaling field or until the number of remaining hops becomes 0 (when I2I forwarding fails), the forwarding station selects one of the following two methods .

Continuing with V2V forwarding: The above-mentioned geo-networking method using I2I forwarding is the same as general geo-networking method using V2V forwarding except for the procedure for finding RIS capable of I2I forwarding. Operation is fully compatible. Therefore, we can continue with V2V forwarding.

Aborting all V2V forwarding: Attempting I2I forwarding is generally suitable for geo-networking packet forwarding over medium-range, so existing V2V forwarding attempts over the ITS-G5 channel are likely to fail, have. Therefore, the V2V forwarding may not be continued.

Thus, if I2I forwarding fails, the forwarding station may perform one of the two above methods.

23 shows a structure of a geo-networking header according to another embodiment of the present invention. In particular, FIG. 23 shows the geo-networking header structure of a beacon packet. The basic header and the common header of the geo-networking header of the beacon packet may include all or a part of the fields included in the basic header and the common header of the geo-networking header described in Figs. 20 to 22.

23 (a) shows an exemplary structure of a geo-networking packet (or ITS-G5 packet), FIG. 23 (b) shows an exemplary structure of a geo-networking header, Shows an exemplary structure of an extension header. In FIG. 23, duplicate description is omitted in FIGS. 3, 8 and 20-22.

23C, in the case of a beacon packet (geo networking beacon), the extension header in the geo-networking header includes at least one of the geo-address, geo-location or time information of the ITS station transmitting the beacon packet SO PV field. This is the same as described above with reference to FIG.

However, unlike FIG. 8, in order to help the source station to more effectively set up the packet delivery path through I2I, the RIS may send information about neighboring RISs nearby (e.g., neighboring RIS's geo-address and geo-location Etc.) can be added to the IRL (Incremental RIS List) field. For example, the IRL field may be included in the extension header in the geo-networking header. In the present specification, the IRL field may be referred to as a RIS list field.

24 shows a structure of an IRL field according to an embodiment of the present invention. In the embodiment of FIG. 24, the IRL field may be included in the extension header in the geo-networking header of FIG.

Referring to FIG. 24, the IRL field may include an RIS count field and / or an RIS geo-location field.

The RIS count field may indicate the number of RISs. The RIS count field can be used to indicate the number of neighboring RISs included in the current beacon. As an example, the RIS count field may have a size of one octet.

As an example, the IRL field may include as many RIS geo-location fields as the number of RIS indicated by the RIS count field as a subroutine. For example, if the size of the RIS list is 12, the length of the extension header may be 217 octets (= 24 + 1 + 16x12).

The RIS geo-location field can provide location information for the neighboring RIS. As an example, the RIS geo-location field may comprise a geo-address field, a latitude field, and / or a longitude field. On the other hand, since the RIS is a fixed station, the RIS geo-location information does not include motion information (e.g., direction, speed, etc.) of the ITS station.

The geo-address field may indicate the geo-networking address of the RIS. The latitude field can indicate the reference location (latitude) of the corresponding RIS. The longitude field can indicate the reference location (longitude) of the corresponding RIS.

As described above, the RIS capable of I2I forwarding basically has the geo-location information of the neighboring RIS and the connection information (network connection information) on the infrastructure network so that the received geo-networking packet can be forwarded to the I2I. However, as described above, the beacon packet includes the IRL information (RIS list) including information on neighboring RISs. This is because the source station (VIS) attempting geo-networking forwarding transmits the IRL information So that the packet transmission path through the network can be effectively selected.

## This section describes the tunneling technique of geo-networking packets to provide efficient I2I forwarding in various infrastructure network environments.

As described above, the infrastructure network of C-ITS can support various upper layers based on IP, and the network topology can also be various. In this situation, direct packet transmission between RISs participating in I2I forwarding needs to be guaranteed in order to achieve low-delay transmission such as V2V forwarding even in I2I forwarding. In other words, a geo-networking packet tunneling scheme for I2I forwarding for rapid message delivery, without the repetition of encoding / parsing of the message via the CIS and the compatibility of the upper layers, as in the embodiment of FIG. 17, Needs to be considered. Such a geo-networking packet tunneling technique may be a method of directly inserting a geo-networking packet transmitted through an ITS-G5 channel into a UDP / IP payload or a TCP / IP payload.

25 illustrates a method for delivering geo-networking packets using an infrastructure according to an embodiment of the present invention. In the embodiment of FIG. 25, for convenience of explanation, it is assumed that geo-networking packet tunneling is performed through a TCP / IP payload. However, the same or similar description can be applied to geo-networking packet tunneling via UDP / IP payload, USP / IP payload, and the like. That is, various network / transport layer protocols can be applied instead of the TCP / IP protocol.

Referring to FIG. 25, the source station VIS may generate a message (for example, a DENM message) for the ITS-G 5 through a facility layer process according to a request from an application. This message is then transmitted over the ITS-G5 channel through the GeoNet layer and ITS-G5 access layer processing. The generated packet (ITS-G5 packet) may include an ITS-G5 access header, a geo networking header, and a PDU.

If an ITS-G5 packet is delivered to an I2I forwardable RIS, the RIS may remove the ITS-G5 access header through the ITS-G5 access layer process. Later, the RIS can insert TCP / IP payloads with geo-networking headers and PDUs through GeoNet layer processing and TCP / IP layer processing, and add TCP / IP headers to create TCP / IP packets . The I2I forwarding capable RIS has geo-location information of the neighboring RIS and network connection information (e.g., IP address / port number, etc.) to the neighboring RIS. Therefore, the RIS can apply the network connection information to the TCP / IP header to connect to the RIS adjacent to the destination. Then, the packet is subjected to access layer processing, and then transmitted to the RIS adjacent to the destination via the infrastructure network. The generated packet (TCP / IP packet) may include an access header, a TCP / IP header, a geo-networking header, and a PDU.

When a TCP / IP packet is forwarded to an RIS adjacent to the destination, the RIS removes the access header and the TCP / IP header through access layer processing and TCP / IP layer processing to create a geo-networking packet containing the GeoNet header and PDU Can be extracted. The RIS then generates an ITS-G5 packet by adding an ITS-G5 access header to the geo-networking packet through GeoNet layer processing and ITS-G5 layer processing and transmits it to the forwarding station (VIS) through the ITS-G5 channel . The ITS-G5 packet thus transmitted may be transmitted to the destination station (VIS) through V2V forwarding.

In the case of using the geo-networking packet tunneling technique, rather than determining the packet delivery path using geo-network information such as geo-location information or geo-address between RISs, RISs are connected based on existing IP network information . Thus, geo-networking packets can be I2I forwarded regardless of whether they are compatible with the upper layer between the RISs. Meanwhile, according to the embodiment, the packet path on the infrastructure network topology may pass through the CIS. However, since the CIS is not the destination, the packet passes through the CIS without any processing, Lt; / RTI > That is, the packet can be delivered to the RIS near the destination without repeated encoding / parsing of the message via the CIS.

Compared with the ITS-G5, the cellular network has a wide communication range and has an advantage that the existing network can be used as it is. Thus, such a cellular network can be used as an infrastructure network. In this case, it is necessary to consider a configuration for a hybrid communication network combining the cellular network and the ITS-G5.

On the other hand, the cellular network can support the internal handover between the eNodeBs in the UTRAN / E-UTRAN without a packet core (EPC) connection required for general IP network connection or registration / control owing to the inherent topology. Thus, if the RIS includes an eNodeB module, geo-networking packets can be easily forwarded over the X2 link in the UTRAN / E-UTRAN. The RIS, including the eNodeB module, should store the geolocation information of the RIS, including the adjacent eNodeB module. When the I2I capability field described above in FIG. 21 has the fourth value 11, the packet can be delivered through the cellular handover.

## The following describes the specific operation mechanism of each ITS station in the geo-networking method using I2I forwarding.

As described above with reference to Figs. 18 and 19, there can be five kinds of ITS stations participating in geo-networking packet transmission using I2I communication. For example, the type of the ITS station may be a VIS source station, a VIS inwarding station, a RIS inwarding station (RIS (first RIS) adjacent to the source station), a RIS inwarding station (RIS ) And a destination station that is a VIS. Since the destination station operates in the same manner as the geo-networking method using the general V2V forwarding, the specific operation of the four types of stations except the destination station will be described below.

In the embodiment of FIG. 27, the source station can only transmit geo-networking packets over the ITS-G5 channel / network. Thus, the source station may first initialize the ITS-G5 access function and the geo-networking function.

The source station may generate a transmission message. When an application / service operating in the application layer requests message generation from the facility layer, the source station may generate ASN.1 or XML-type messages (e.g., CAM or DENM messages) through facility layer processing. The generated message corresponds to the PDU of the geo-networking packet.

The source station may determine whether to use I2I forwarding. The source station may select the transmission path for the PDU of the generated geo-networking packet, and may then decide whether to use I2I forwarding.

As an example, the source station may receive information about the neighboring ITS stations from the beacon packets received from neighboring neighboring ITS stations (e.g., information about the RIS capable of forwarding VIS and I2I around the source station (e.g., )). &Lt; / RTI > The source station may also configure location table / information based on the obtained information, including information about at least one neighboring ITS station executing a geo-networking protocol. The source station may determine whether to use I2I forwarding based on preconfigured location information. The beacon packet used for constructing the location information is as described above with reference to FIG.

If the use of I2I forwarding is determined, the source station may insert an I2I priority field into the geo-networking header. When the I2I priority field is activated (i.e., I2I forwarding has priority), the source station includes a lifetime type field and a lifetime value field indicating the maximum time (maximum valid time) or the number of remaining hops The I2I lifetime field can be inserted into the geo-networking header. Thereby, the margin at which the forwarding station is selected with I2I forwarding during multi-hop transmission can be set.

The source station may insert the remaining fields in the geo-networking header to generate geo-networking packets. In this case, the source station can perform the same operation as generating an existing geo-networking header.

The source station can send geo-networking packets over the ITS-G5 channel. In this case, the source station can process the geo-networking packet as an ITS-G5 packet through the ITS-G5 access layer process and transmit it through the ITS-G5 channel.

In the embodiment of FIG. 28, since the forwarding station corresponds to the VIS, it can transmit geo-networking packets only through the ITS-G5 channel. Thus, the forwarding station may first initialize the ITS-G5 access function and the geo-networking function.

The forwarding station may receive geo-networking packets. As an example, the forwarding station may receive geo-networking packets over the ITS-G5 channel. If a geo-networking packet is not received, the forwarding station can wait to receive a geo-networking packet.

When a geo-networking packet is received, the forwarding station may check the I2I priority field in the geo-networking header.

When the I2I priority is activated (e.g., the I2I priority field is set to 1), the forwarding station may check the lifetime type field. Thereafter, the forwarding station may determine whether the lifetime (I2I lifetime) for I2I forwarding according to the lifetime type field has expired. As described above, the I2I lifetime can be signaled to either the maximum time or the number of remaining hops depending on the value of the lifetime type field.

When the I2I lifetime expires, the forwarding station may perform an operation in case of a preset I2I forwarding failure. This is as described above in Fig. Alternatively, if the I2I lifetime has not expired, the forwarding station may determine if the V2V forwarding algorithm is GFA or CBFA.

If it is determined that the V2V forwarding algorithm is a GFA, the forwarding station can search for an RIS (I2I valid RIS) capable of I2I forwarding. In case of the GFA, the forwarding station must select the next forwarding station, so that the forwarding station can search for the RIS capable of I2I forwarding using the information about the already stored neighboring ITS station (neighboring ITS station information). As described above, the neighboring ITS station information may be included in the location table, and the location table may be configured based on the beacon packet received from the neighboring ITS station.

If an RIS capable of I2I forwarding is found, the forwarding station may select this RIS as the next forwarder. Alternatively, if no RIS capable of I2I forwarding is found, the forwarding station may perform an existing GFA operation. This is the same as described above with reference to FIG.

If it is determined that the V2V forwarding algorithm is a CBFA, the forwarding station may perform an existing CBFA operation. This is the same as described above with reference to FIGS.

The forwarding station may then transmit the geo-networking packet to the next forwarding station via ITS-G5.

On the other hand, if the I2I priority is not active (e.g., the I2I priority field is set to zero), the forwarding station may determine whether the V2V forwarding algorithm is a GFA and perform an existing GFA operation or an existing CBFA operation accordingly have.

29 is a flow diagram illustrating the geo-networking operation of a forwarding station that is an RIS adjacent to a source station in accordance with an embodiment of the present invention. This forwarding station may also be referred to as a first RIS or source station adjacent RIS (source neighbor RIS).

In the embodiment of FIG. 29, the forwarding station may transmit geo-networking packets received over the ITS-G5 network through the infrastructure network. Thus, the forwarding station may first initialize the ITS-G5 access function, the geo-networking function, and the infrastructure access function.

The forwarding station may receive geo-networking packets. The forwarding station can receive geo-networking packets over the ITS-G5 channel. If a geo-networking packet is not received, the forwarding station can wait to receive a geo-networking packet.

When the I2I priority is activated (e.g., the I2I priority field is set to 1), the forwarding station may check the lifetime type field. Thereafter, the forwarding station can check the lifetime (I2I lifetime) for I2I forwarding according to the lifetime type field. As described above, the I2I lifetime can be signaled to either the maximum time or the number of remaining hops depending on the value of the lifetime type field.

When the I2I lifetime expires, the forwarding station may perform an operation in case of a preset I2I forwarding failure. This is as described above in Fig. Alternatively, if the I2I lifetime has not expired, the forwarding station may determine whether the geo-networking packet is duplicated. As an example, the forwarding station checks whether the geo-networking packet is duplicated by checking whether the currently received geo-networking packet is the same as the previously received geo-networking packet (e.g., whether it contains the same geo networking header and PDU) Can be determined. This allows the forwarding station to forward only the first received geo-networking packet and discard the subsequently received duplicate geo-networking packet. If the geo-networking packet is duplicated, the forwarding station can discard the currently received geo-networking packet.

If the geo-networking packet is not duplicated, the forwarding station can retrieve the RIS adjacent to the destination of the geo-networking packet through the infrastructure network. As described above, the forwarding station may use the pre-stored neighboring ITS station information (e.g., geo-location information of the neighboring RIS) and / or networking connection information (e.g., IP address and port number) You can search. As described above, the neighboring ITS station information may be included in the location table, and the location table may be configured based on the beacon packet received from the neighboring ITS station.

The forwarding station can perform GeoNet packet tunneling (I2I forwarding). Specifically, the forwarding station may transmit an I2I packet containing geo-networking packets received over the ITS-G5 channel to an RIS adjacent to the destination. At this time, the I2I packet can be generated by mapping the geo-networking packet to the payload of the packet of the network protocol of the infrastructure network (e.g., TCP / IP or UDP / IP protocol). This is the same as described above with reference to Fig.

On the other hand, if the I2I priority is not active (e.g., the I2I priority field is set to zero), the forwarding station may determine whether the V2V forwarding algorithm is a GFA and perform an existing GFA operation or an existing CBFA operation accordingly have. This is the same as described above with reference to Figs.

FIG. 30 is a flowchart illustrating a geo-networking operation of a forwarding station that is an RIS adjacent to a destination station according to an embodiment of the present invention. This forwarding station may also be referred to as a second RIS or destination station adjacent RIS (destination neighbor RIS).

In the embodiment of FIG. 30, the forwarding station may transmit the received geo-networking packet over the infrastructure network (via I2I forwarding) over the ITS-G5 channel. Thus, the forwarding station may first initialize the ITS-G5 access function, the geo-networking function, and the infrastructure access function.

The forwarding station may receive geo-networking packets. The forwarding station can receive I2I packets containing geo-networking packets through the infrastructure station network (I2I communication). If the I2I packet is not received, the forwarding station may wait to receive the geo-networking packet.

When an I2I packet is received, the forwarding station may analyze the PDU / payload of the received I2I packet (e.g., TCP / IP packet). The forwarding station may determine whether the payload of the I2I packet includes a geo-networking header.

If the payload of the I2I packet includes a geo-networking header, the forwarding station may determine whether the geo-networking packet is duplicated. As an example, the forwarding station checks whether the geo-networking packet is duplicated by checking whether the currently received geo-networking packet is the same as the previously received geo-networking packet (e.g., whether it contains the same geo networking header and PDU) Can be determined.

If the geo-networking packet is duplicated, the forwarding station can discard the currently received geo-networking packet. Alternatively, if the geo-networking packet is not duplicated, the forwarding station may deactivate the I2I priority (e.g., set the I2I priority field to zero). This allows geo-networking packets to be delivered to the destination via the ITS-G5 channel in the remaining path.

The forwarding station may then determine whether the forwarding algorithm is a GFA and perform an existing GFA operation or an existing CBFA operation accordingly. The forwarding station can send geo-networking packets over the ITS-G5 channel. This is the same as described above with reference to Figs.

On the other hand, if the payload of the I2I packet does not include a geo networking header, the forwarding station can perform an existing infrastructure operation.

In Figure 31, the V2X communication device 31000 may include a communication unit 31010, a processor 31020, and a memory 31030.

Communication unit 31010 may be coupled to processor 31020 to transmit / receive wireless signals. The communication unit 31010 can upconvert the data received from the processor 31020 to the transmission / reception band and transmit the signal or downconvert the reception signal. The communication unit 31010 may implement the operation of at least one of a physical layer and an access layer.

Communication unit 31010 may comprise a plurality of sub-RF units for communicating in accordance with a plurality of communication protocols. As an example, communication unit 31010 may be an ITS-G5 wireless communication technology based on DSRC (Dedicated Short Range Communication), IEEE 802.11 and / or 802.11p standards, physical transmission techniques of IEEE 802.11 and / or 802.11p standards, Data communication based on 2G / 3G / 4G (LTE) / 5G wireless cellular communication technology including broadband wireless mobile communication, broadband terrestrial digital broadcasting technology such as DVB-T / T2 / ATSC, GPS technology and IEEE 1609 WAVE technology Can be performed. Communication unit 31010 may comprise a plurality of transceivers implementing each communication technology.

Communication unit 31010 includes a plurality of transceivers, with one transceiver communicating on the CCH and the other transceiver communicating on the SCH. The communication unit 31010 can perform multi-channel operation using a plurality of transceivers.

The processor 31020 may be coupled to the RF unit 31030 to implement the operation of the layers according to the ITS system or the WAVE system. Processor 31020 may be configured to perform operations in accordance with various embodiments of the present invention in accordance with the above figures and description. Also, at least one of the modules, data, programs, or software that implement the operation of the V2X communication device 31000 according to various embodiments of the invention described above may be stored in memory 31010 and executed by processor 31020 have.

The memory 31010 is connected to the processor 31020 and stores various information for driving the processor 31020. [ Memory 31010 may be internal to processor 31020 or external to processor 31020 and may be coupled to processor 31020 by known means.

The processor 31020 of the V2X communication device 31000 can perform geo-networking packet transmission by performing the geo-networking method using the I2I forwarding described in the present invention. The geo-networking packet transmission method of the V2X communication apparatus 31000 will be described below.

32 is a flowchart illustrating a geo-networking transmission method of a V2X communication apparatus according to an embodiment of the present invention. In the embodiment of FIG. 32, the V2X communication device may be the forwarding station (VIS) of FIG.

The V2X communication apparatus can receive the geo-networking packet (S32010). As an example, the geo-networking packet may include I2I priority information indicating that I2I forwarding has priority and I2I lifetime information providing I2I lifetime related information.

As an example, the I2I lifetime information may include lifetime type information indicating a type of I2I lifetime and lifetime value information indicating a value of I2I lifetime depending on the type. The type of I2I lifetime may be a first type whose I2I lifetime is indicated by a maximum allowed time or a second type whose lifetime is indicated by an I2I lifetime. When the type of I2I lifetime is the first type, the lifetime value information indicates a value of the maximum allowed time until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding, and the type of I2I lifetime is the second type The lifetime value information may indicate the value of the remaining hop count until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding. 21 and 22, detailed description thereof will be omitted.

The V2X communication device may determine whether I2I forwarding is prioritized based on the I2I priority information (S32020).

If the I2I forwarding has priority, the V2X communication device may determine whether the lifetime of the I2I forwarding has expired based on the I2I lifetime information (S32030).

If the lifetime of the I2I forwarding has not expired, the V2X communication device may transmit the geo-networking packet (S32040). As an embodiment, the V2X communication device can determine the V2X communication device capable of I2I forwarding as a forwarder based on the location information, and transmit the geo-networking packet to the forwarder. At this time, the location information may include information on at least one neighbor V2X communication device executing the geo-networking protocol. As an example, location information may be configured based on beacon packets received from at least one neighbor V2X communication device.

As an example, the beacon packet may include I2I capability information indicating the I2I forwarding capability of the V2X communication device transmitting the beacon packet. The beacon packet may also include IRL information including information about at least one neighboring RIS in the vicinity of the V2X communication device transmitting the beacon packet. The IRL information may include an RIS count field indicating the number of neighboring RISs and an RIS geolocation field providing location information for neighboring RISs. This is the same as described above with reference to FIG.

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 explicitly cited in the claims can 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 which performs 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 understood by those skilled in the art that various changes and modifications can be made therein without departing from the spirit or scope of the invention. Accordingly, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

In the present specification, the apparatus and method inventions are all referred to, and descriptions of both the apparatus and method inventions can be supplemented and applied to each other.

Various embodiments have been described in the best mode for carrying out the invention.

The present invention is used in a range of vehicle communications.

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. Accordingly, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

In a geo-networking transmission method of a V2X communication device,

Receiving a geo-networking packet, the geo-networking packet including I2I priority information indicating that the I2I forwarding has priority and I2I lifetime information providing I2I lifetime related information; Receiving;

Determining whether I2I forwarding is prioritized based on the I2I priority information;

If the I2I forwarding has a priority, determining whether the lifetime of the I2I forwarding has expired based on the I2I lifetime information; And

And if the lifetime of the I2I forwarding has not expired, sending the geo-networking packet.
The method according to claim 1,

Wherein the transmitting the geo-networking packet comprises:

Determining, as a forwarder, a V2X communication device capable of I2I forwarding based on location information, the location information including information about at least one neighbor V2X communication device executing a geo-networking protocol; And

And transmitting the geo-networking packet to the forwarder.
3. The method of claim 2,

Wherein the location information is configured based on a beacon packet received from the at least one neighbor V2X communication device,

The beacon packet includes:

And I2I capability information indicating an I2I forwarding capability of the V2X communication device transmitting the beacon packet.
The method of claim 3,

The beacon packet includes:

Wherein the IRL information includes an RIS count field indicating a number of the neighboring RISs and an IRL information indicating a number of neighboring RISs for the neighboring RISs, A geo-networking transmission method, comprising: a RIS geolocation field providing location information.
The method according to claim 1,

The I2I life-

Life type information indicating a type of the I2I lifetime and a lifetime value information indicating a value of the I2I lifetime according to the type, wherein the type of the I2I lifetime includes a first type in which the I2I lifetime is indicated by a maximum allowable time Type or the second type indicated by the number of hops where the I2I lifetime remains.
6. The method of claim 5,

When the type of the I2I lifetime is the first type, the lifetime value information indicates a value of the maximum allowed time until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding,

And the lifetime value information indicates a value of the remaining hop count until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding when the type of the I2I lifetime is the second type.
In the V2X communication apparatus,

A memory for storing data;

A communication unit for transmitting and receiving a radio signal including geo-networking packets; And

And a processor for controlling the memory and the communication unit,

The processor comprising:

The geo-networking packet including I2I lifetime information providing I2I priority information and I2I lifetime related information indicating whether I2I forwarding has priority;

Determine whether I2I forwarding is prioritized based on the I2I priority information;

If the I2I forwarding has a priority, determining whether the lifetime of the I2I forwarding has expired based on the I2I lifetime information; And

And transmits the geo-networking packet when the lifetime of the I2I forwarding has not expired.
8. The method of claim 7,

Transmitting the geo-networking packet comprises:

Determining, as a forwarder, a V2X communication device capable of forwarding the I2I based on location information, the location information including information about at least one neighbor V2X communication device executing a geo-networking protocol; And

And sending the geo-networking packet to the forwarder.
9. The method of claim 8,

Wherein the location information is configured based on a beacon packet received from the at least one neighbor V2X communication device,

The beacon packet includes:

And I2I capability information indicating an I2I forwarding capability of the V2X communication device transmitting the beacon packet.
10. The method of claim 9,

The beacon packet includes:

Wherein the IRL information includes an RIS count field indicating a number of the neighboring RISs and an IRL information indicating a number of neighboring RISs for the neighboring RISs, And a RIS geolocation field providing location information.
8. The method of claim 7,

The I2I life-

Life type information indicating a type of the I2I lifetime and a lifetime value information indicating a value of the I2I lifetime according to the type, wherein the type of the I2I lifetime includes a first type in which the I2I lifetime is indicated by a maximum allowable time Type or the second type indicated by the number of hops where the I2I lifetime remains.
12. The method of claim 11,

When the type of the I2I lifetime is the first type, the lifetime value information indicates a value of the maximum allowed time until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding,

And the lifetime value information indicates a value of a remaining hop count until the geo-networking packet is delivered to the V2X communication device capable of I2I forwarding when the type of the I2I lifetime is the second type.