A data service method, system and communication device

Abstract

The application discloses a data service method, system and communication device. The method comprises the following steps: a roadside device sends a service announcement message through a main communication channel, the service announcement message comprises service information and channel information, the service announcement message is used for announcing at least one service provided to a vehicle-mounted device and the corresponding backup communication channel information of each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel; the roadside device receives a service response message sent by the vehicle-mounted device, the service response message comprises at least one service identifier and a first identifier corresponding to the service identifier, the first identifier represents subscription or refusal to subscribe to the service; and the roadside device establishes a first corresponding relationship between a first service and at least one vehicle-mounted device based on the service response message of the plurality of vehicle-mounted devices, the first identifier in the service response message of the at least one vehicle-mounted device represents subscription to the first service, and the first service is any one of the at least one service.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication technology, in particular to a data service method, system and communication device. BACKGROUND

[0002] The method for realizing the data service of vehicle-road cooperation based on the cellular network vehicle wireless communication technology (C-V2X, Cellular Vehicle-to-Everything) is to respectively deploy C-V2X modules on roadside devices and vehicle-mounted devices, so that the roadside devices and the vehicle-mounted devices transmit the international message set such as the map message (MAP), the traffic light phase and timing message (SPAT, Signal Phase Timing Message) and the basic safety message (BSM, Basic Safety Message) on the same frequency point communication channel, and realize the vehicle-to-vehicle communication (V2V, Vehicle to Vehicle), vehicle-to-infrastructure communication (V2I, Vehicle to Infrastructure) and other scenes on the vehicle terminal through the information carried by the message set, such as vehicle speed induction, intersection traffic light service, vehicle collision warning and the like.

[0003] The method for realizing the data service of the roadside device and each vehicle-mounted device on the same C-V2X communication channel occupies a large amount of bandwidth of the communication channel when performing file transmission and other data services, causes the high-frequency data in the message set to be blocked, and thus affects the scene calculation of the high-frequency scene (such as collision warning, weak traffic participant scene and the like), and causes the network entity to have a large load. SUMMARY

[0004] To solve the existing technical problems, the embodiments of the present application provide a data service method, device, communication device and storage medium.

[0005] To achieve the above-mentioned purpose, the technical scheme of the embodiments of the present application is as follows:

[0006] The embodiments of the present application provide a data service method, which is applied to a roadside device, the roadside device is deployed with at least two communication modules, and the method comprises the following steps: the roadside device sends a service announcement message through a main communication channel, the service announcement message comprises service information and channel information, the service announcement message is used to announce at least one service provided by the vehicle-mounted device and the corresponding backup communication channel information of each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel.

[0007] The roadside device receives a service response message sent by the vehicle-mounted device, and the service response message includes at least one service identifier and a first identifier corresponding to each service identifier, the first identifier indicating subscription to a service or rejection of subscription to the service;

[0008] The roadside device establishes a first correspondence between a first service and at least one vehicle-mounted device based on service response messages of a plurality of vehicle-mounted devices, the first identifier corresponding to the at least one vehicle-mounted device in the service response message indicating subscription to the first service, the first service being any one of the at least one service, and the first backup communication channel information corresponding to the first service being used by the roadside device to switch to a first backup communication channel to provide the first service.

[0009] In the above scheme, before the roadside device sends a service announcement message through the main communication channel, the method further includes: the roadside device determining a main communication frequency based on a main frequency point corresponding to the main communication channel;

[0010] The roadside device selects a backup communication frequency corresponding to each service for the at least one service based on the main communication frequency and a preset frequency range, and determines a backup frequency point based on the backup communication frequency;

[0011] The backup communication channel information corresponding to each service includes a backup frequency point determined based on the backup communication frequency selected for each service.

[0012] In the above scheme, the method further includes: the roadside device sending a service query message through the first backup communication channel corresponding to the first service, the service query message being used to confirm whether vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel;

[0013] The roadside device determines whether a service reply message sent by a vehicle-mounted device is received, and if the service reply message sent by the vehicle-mounted device is received, it is determined that the vehicle-mounted device switches to access the first backup communication channel, and if the service reply message sent by the vehicle-mounted device is not received, it is determined that the vehicle-mounted device does not switch to access the first backup communication channel.

[0014] In the above scheme, the service query message includes: a device identifier field used to identify at least one vehicle-mounted device corresponding to the first service, a service identifier field used to identify the first service, and a service state field used to identify a service state;

[0015] When the values of the device identifier fields in the service query message are all set to a first value, the service query message is used to confirm whether all vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel;

[0016] The service query message further includes a device identifier of a specific vehicle-mounted device when the value of the device identifier field in the service query message is not all the first value, and the service query message is used to confirm whether the specific vehicle-mounted device switches to access the first backup communication channel to subscribe to the first service.

[0017] In the above solution, the method further includes: after the roadside device performs block processing on the to-be-transmitted data, the roadside device sends a file service start message through the first backup communication channel corresponding to the first service, and the file service start message includes related information of the to-be-transmitted data, and the related information of the to-be-transmitted data includes a file name, a file block size, a file block quantity, and file check information.

[0018] In the above solution, the method further includes: the roadside device sends a first file service transmission message through the first backup communication channel, and the first file service transmission message includes a first file block identifier and a file block corresponding to the first file block identifier.

[0019] The roadside device receives a first file block response message sent by the vehicle-mounted device, and the first file block response message at least includes a received first file block identifier.

[0020] In the above solution, the roadside device receives a first file block response message sent by the vehicle-mounted device, including: after the roadside device sends the first file service transmission message, the roadside device starts a timer, and receives the first file block response message sent by the vehicle-mounted device within a timing range of the timer.

[0021] In the above solution, the method further includes: if the roadside device does not receive a first file block response message sent by any vehicle-mounted device subscribing to the first service within a timing range of the timer, the roadside device re-sends a service query message through the first backup communication channel, and the service query message is used to confirm whether all vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel.

[0022] When the roadside device does not receive a service reply message sent by any vehicle-mounted device, it is confirmed that the data transmission fails.

[0023] In the above solution, the method further includes: if the roadside device does not receive a first file block response message sent by a first vehicle-mounted device subscribing to the first service within a timing range of the timer, the roadside device re-sends a service query message through the first backup communication channel, and the service query message is used to confirm whether the first vehicle-mounted device switches to access the first backup communication channel; and the first vehicle-mounted device is any vehicle-mounted device among all vehicle-mounted devices subscribing to the first service.

[0024] If the road-side device does not receive the service reply message sent by the first vehicle-mounted device, it is determined that the first vehicle-mounted device has left the first correspondence relationship;

[0025] If the road-side device receives the service reply message sent by the first vehicle-mounted device, it re-sends the first file service transmission message through the first backup communication channel.

[0026] In the above scheme, the method further comprises: if the road-side device receives the first file block response message sent by all vehicle-mounted devices subscribing to the first service within the timing range of the timer, it continues to send the second file service transmission message through the first backup communication channel, and the second file service transmission message includes a second file block identifier and a file block corresponding to the second file block identifier.

[0027] In the above scheme, the method further comprises: after the transmission of the to-be-transmitted data is completed, the road-side device receives the transmission completion notification message sent by the vehicle-mounted device.

[0028] The embodiment of the application provides a data service method, the vehicle-mounted device is provided with at least two communication modules, the method is applied to the vehicle-mounted device, and the method comprises the following steps: the vehicle-mounted device receives a service notification message sent by a road-side device through a main communication channel, the service notification message comprises service information and channel information, the service notification message is used for notifying the vehicle-mounted device of at least one service provided and backup communication channel information corresponding to each service, and the frequency point of the backup communication channel corresponding to the backup communication channel information is different from that of the main communication channel.

[0029] The vehicle-mounted device determines a first service subscribed and first backup communication channel information corresponding to the first backup communication channel corresponding to the first service according to the service information and the channel information, sends a service response message to the road-side device, the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, indicating subscription service or refusal to subscribe to the service, and the first backup communication channel information is used for switching the vehicle-mounted device to the first backup communication channel to use the first service.

[0030] In the above scheme, the service information comprises: at least one service identifier, service description information corresponding to each service, and backup communication channel identifier corresponding to each service; and / or,

[0031] The channel information comprises the following information of the backup communication channel corresponding to each service: backup communication channel identifier, frequency point of the backup communication channel, and state information of the backup communication channel.

[0032] The vehicle-mounted device determines a first service subscribed by the vehicle-mounted device and first backup communication channel information corresponding to a first backup communication channel corresponding to the first service according to the service information and the channel information, including: the vehicle-mounted device determines a first service subscribed by the vehicle-mounted device according to the service information, finds the first service according to the identification of the first service, and determines a first backup communication channel identification corresponding to the first service.

[0033] The first backup communication channel information includes a frequency point of the backup communication channel and state information of the backup communication channel.

[0034] In the above scheme, the method further includes: the vehicle-mounted device switches to the first backup communication channel based on the first backup communication channel information.

[0035] In the above scheme, the method further includes: the vehicle-mounted device receives a service query packet sent by the road-side device through the first backup communication channel, and the service query packet is used to confirm whether the vehicle-mounted device subscribed to the first service switches to access the first backup communication channel.

[0036] The vehicle-mounted device sends a service reply packet to the road-side device.

[0037] In the above scheme, the method further includes: the vehicle-mounted device receives a file service start packet sent by the road-side device through the first backup communication channel, and the file service start packet includes related information of to-be-transmitted data, and the related information of the to-be-transmitted data includes a file name, a file block size, a file block quantity, and file check information.

[0038] In the above scheme, the method further includes: the vehicle-mounted device receives a first file service transmission packet sent by the road-side device through the first backup communication channel, and the first file service transmission packet includes a first file block identification and a file block corresponding to the first file block identification.

[0039] The vehicle-mounted device sends a first file block response packet to the road-side device, and the first file block response packet includes at least a received first file block identification.

[0040] In the above scheme, the method further includes: after the to-be-transmitted data is transmitted, the vehicle-mounted device checks the to-be-transmitted data and file check information, and sends a transmission completion notification packet to the road-side device after the check is passed.

[0041] In the scheme, the method further comprises: after the first service ends, the vehicle-mounted device switches back to the main communication channel from the first backup communication channel if it is confirmed that the first backup communication channel has no other service.

[0042] The embodiment of the application further provides a data service system, which comprises: a roadside device and a vehicle-mounted device, wherein the roadside device and the vehicle-mounted device are both provided with at least two communication modules; and

[0043] The roadside device is configured to send a service announcement message through a main communication channel, wherein the service announcement message comprises service information and channel information, and the service announcement message is used to announce at least one service provided by the roadside device and backup communication channel information corresponding to each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel.

[0044] The vehicle-mounted device is configured to receive the service announcement message sent by the roadside device through the main communication channel; and further configured to determine, through the service information and the channel information, a first service subscribed by the vehicle-mounted device and first backup communication channel information corresponding to a first backup communication channel corresponding to the first service, send a service response message to the roadside device, wherein the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, which indicates whether to subscribe to the service; and the first backup communication channel information is used for switching the vehicle-mounted device to the first backup communication channel to use the first service.

[0045] The roadside device is further configured to receive the service response message sent by the vehicle-mounted device; and establish a first corresponding relationship between the first service and at least one vehicle-mounted device based on service response messages of a plurality of vehicle-mounted devices, wherein the first identifier in the service response message corresponding to the at least one vehicle-mounted device indicates that the first service is subscribed, and the first service is any one of the at least one service; and the first backup communication channel information corresponding to the first service is used for switching the roadside device to the first backup communication channel to provide the first service.

[0046] The embodiment of the application further provides a data service device, which is applied to a roadside device, wherein the roadside device is provided with at least two communication modules, and the device comprises: a first sending unit, a first receiving unit and a first processing unit.

[0047] The first sending unit is configured to send a service announcement message through a main communication channel, wherein the service announcement message comprises service information and channel information, and the service announcement message is used to announce at least one service provided by the roadside device and backup communication channel information corresponding to each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel.

[0048] The first receiving unit is configured to receive a service response message sent by the vehicle-mounted device, wherein the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, the first identifier indicating subscription or rejection of subscription of a service.

[0049] The first processing unit is configured to establish a first correspondence relationship between a first service and at least one vehicle-mounted device based on service response messages of a plurality of vehicle-mounted devices, wherein the first identifier in the service response message corresponding to the at least one vehicle-mounted device indicates subscription of the first service, the first service is any one of the at least one service, and the first backup communication channel information corresponding to the first service is used for switching the road-side device to a first backup communication channel to provide the first service.

[0050] The embodiment of the present application further provides a data service device, which is applied to a vehicle-mounted device, wherein the vehicle-mounted device is provided with at least two communication modules, and the device comprises a second receiving unit, a second processing unit and a second sending unit.

[0051] The second receiving unit is configured to receive a service announcement message sent by a road-side device through a main communication channel, wherein the service announcement message comprises service information and channel information, and the service announcement message is used for announcing at least one service provided by the road-side device and backup communication channel information corresponding to each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from that of the main communication channel.

[0052] The second processing unit is configured to determine a first service to be subscribed and first backup communication channel information corresponding to the first backup communication channel corresponding to the first service by using the service information and the channel information.

[0053] The second sending unit is configured to send a service response message to the road-side device, wherein the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, the first identifier indicating subscription or rejection of subscription of a service, and the first backup communication channel information is used for switching the vehicle-mounted device to a backup communication channel to use the first service.

[0054] The embodiment of the present application further provides a communication device, which comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, wherein the processor implements the steps of the data service method applied to the road-side device or the vehicle-mounted device according to the program.

[0055] The embodiment of the present application further provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the program is executed by a processor to implement the steps of the data service method applied to the road-side device or the vehicle-mounted device.

[0056] The data service method, system and communication device provided by the embodiment of the application, on the one hand, the new communication channel is used by applying the multiple C-V2X communication channels to the roadside device and the vehicle-mounted device and establishing the service announcement mechanism corresponding to the communication channel, so that the roadside device can provide the corresponding service on the multiple standby communication channels, thereby establishing the service-oriented cooperative working mechanism between the roadside device and the vehicle-mounted device deployed with the C-V2X module; on the other hand, the vehicle-mounted device obtains the information of the standby communication channel corresponding to the subscribed service through the service announcement sent by the roadside device on the main communication channel, so as to facilitate switching to the standby communication channel to accept the service and avoid more occupation of the main communication channel to reduce the working efficiency of the main communication channel. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 The flowchart of the data service method of the embodiment of the application Figure 1 ;

[0058] Figure 2 The format diagram of the service announcement message provided by the embodiment of the application

[0059] Figure 3 The format diagram of the service response message provided by the embodiment of the application

[0060] Figure 4 The format diagram of the service query message provided by the embodiment of the application

[0061] Figure 5 The flowchart of the file transmission in the data service method of the embodiment of the application

[0062] Figure 6 The format diagram of the file service start message provided by the embodiment of the application

[0063] Figure 7 The format diagram of the file service transmission message provided by the embodiment of the application

[0064] Figure 8 The format diagram of the file block response message provided by the embodiment of the application

[0065] Figure 9 The flowchart of the data service method of the embodiment of the application Figure 2 ;

[0066] Figure 10 The flowchart of the file transmission applied to the vehicle-mounted device provided by the embodiment of the application

[0067] Figure 11 The component structure diagram of the data service system of the embodiment of the application

[0068] Figure 12 This is an optional flowchart illustrating a C-V2X-based data service method provided in an embodiment of the present invention.

[0069] Figure 13 This is a schematic diagram of the composition structure of the data service device according to an embodiment of the present invention. Figure 1 ;

[0070] Figure 14 This is a schematic diagram of the composition structure of the data service device according to an embodiment of the present invention. Figure 2 ;

[0071] Figure 15 This is a schematic diagram of the hardware composition structure of a communication device provided in an embodiment of the present invention. Detailed Implementation

[0072] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0073] The technical solutions of this invention can be applied to various communication systems, such as GSM (Global System of Mobile communication), LTE (Long Term Evolution), or 5G systems. Optionally, a 5G system or 5G network can also be referred to as a New Radio (NR) system or NR network.

[0074] For example, the communication system used in this embodiment of the invention may include network devices and terminal devices (also referred to as terminals, communication terminals, etc.); the network device may be a device that communicates with the terminal device. The network device can provide communication coverage within a certain area and can communicate with terminals located within that area. Optionally, the network device may be a base station in various communication systems, such as an evolved Node B (eNB) in an LTE system, or a gNB in ​​a 5G or NR system.

[0075] Optionally, terminal devices can communicate directly via Device to Device (D2D).

[0076] It should be understood that devices with communication functions in the network / system of this application embodiment can be referred to as communication devices. Communication devices may include network devices and terminals with communication functions. Network devices and terminal devices can be the specific devices described above, which will not be repeated here. Communication devices may also include other devices in the communication system, such as network controllers, mobility management entities, and other network entities. This embodiment of the present invention does not limit these.

[0077] It should be understood that the terms "system" and "network" are often used interchangeably herein. The term "and / or", herein, is merely used to represent an associated relationship between associated objects, and means that three relationships can exist, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the front and rear associated objects.

[0078] The terms "first", "second", and the like in the specification and claims of the present application are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0079] Before further detailing the embodiments of the present application, the terms and terms involved in the embodiments of the present application are explained, and the terms and terms involved in the embodiments of the present application are applicable to the following explanations.

[0080] 1) V2X, Vehicle to Everything, a wireless communication technology for "vehicle to everything", through which network communication technology and other surrounding vehicles, people and things are communicated, and information collected is analyzed and decided.

[0081] 2) C-V2X, Cellular Vehicle-to-Everything, is a wireless communication technology for vehicles based on cellular network, which can be understood as a wireless communication technology for vehicles based on 4G / 5G.

[0082] 3) Dedicated Short Range Communication (DSRC, Dedicated Short Range Communication), is a wireless communication technology for vehicle-to-vehicle and vehicle-to-road communication, DSRC enables vehicles to exchange information with each other and roadside infrastructure to improve road safety and traffic efficiency, and provide various services for drivers and passengers, C-V2X belongs to dedicated short range communication.

[0083] 4)“New Four Crosses”, which is the latest requirement of the “Single Vehicle Intelligence + Networked” cross-industry collaborative test and verification platform for the field of vehicle networking, requires the application of high-precision maps and positioning across the whole vehicle, communication terminals, chip modules, and security platforms, and realizes the transition from intelligent and connected vehicle demonstration to large-scale concurrent testing.

[0084] 5) Evolved Universal Terrestrial Radio Access (E-UTRA) is a commonly used air interface standard for high-speed wireless communication of mobile devices and data terminals.

[0085] The data service method provided by the embodiments of the application can be used in a vehicle-road cooperation environment to provide different data services for vehicle-mounted devices through vehicle wireless communication technology according to different service requirements of the vehicle-mounted devices.

[0086] As an example, the data service method provided by the embodiments of the application can be implemented on a roadside device deployed with a C-V2X module, such as a roadside traffic light, a monitoring device, and other roadside devices that can provide different data services.

[0087] Illustratively, the C-V2X-based roadside device can be deployed at a traffic intersection of a vehicle-road cooperation roadside facility road scene, and through the combination of multiple roadside devices, the vehicle-mounted device deployed with a C-V2X module can be provided with red light information, monitoring information, traffic event information, and other data services.

[0088] As an example, in the data service method provided by the embodiments of the application, the data transmission between the roadside device and the vehicle-mounted device can be realized based on a dedicated short-range communication service announcement (DSA), which is a message frame applied to a dedicated short-range communication (DSRC) service. The message frame format of the DSA is shown in Table 1, and the dedicated short-range communication service announcement message frame can include a frame header and application information.

[0089] Table 1

[0090] Variable Variable Header Application Info

[0091] The frame header (Header) field of the message frame of the DSA is shown in Table 2, and the frame header field can include a service announcement version, a frame header optional indication, a reserved field, a service announcement identification, a content count, and a frame header extension field. The service announcement version (DSA Version) field is used to distinguish different service announcement version numbers (0-15), for example, the service announcement version field can take a value of 0; the frame header optional indication (DSA Header Option Indicator) field can be represented by 0 or 1, and when the value is 1, the frame header extension field (Header Extension) appears, and when the value is 0, the frame header extension field (Header Extension) does not appear; the reserved field is used for extension; the service announcement identification (DSA ID) field is used to identify the uniqueness of the service announcement; the content count (Content Count) field is used to identify whether it is a repetition of the previous service announcement when the service announcement identification is the same; and the frame header extension field (Header Extension) is used to reserve other information.

[0092] Table 2

[0093]

[0094]

[0095] As an example, the application information (Application Info) field of the message frame of the DSA is shown in Table 3, and the application information can include an application information count (Application Info Count) field, an application identification (AID) field, and an application extension field (Application Extension) field. The application information count indicates that there are a total of several application information (Application Info) fields; and the application extension field is used to indicate application-related information.

[0096] Table 3

[0097] 1 byte Variable Variable Application Info Count Application ID Application Extension Field

[0098] In the data service method provided by the embodiment of the application, the messages exchanged between the roadside device and the vehicle-mounted device can be implemented in the DSA shown in Tables 1 to 3, and specifically, the application extension field in Table 3 is newly defined.

[0099] Based on this, the embodiment of the application provides a data service method, Figure 1 The flowchart of the data service method of the embodiment of the application is shown in Figure 1 ; as Figure 1 shown, the method comprises:

[0100] Step 101: The roadside device sends a service announcement message through the main communication channel. The service announcement message includes service information and channel information, and the service announcement message is used to announce at least one service provided by the roadside device to the vehicle-mounted device and the corresponding backup communication channel information of each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel.

[0101] In some embodiments, the main communication channel can be a main communication channel of any wireless communication technology for vehicles. For example, the main communication channel can be a C-V2X-based main communication channel.

[0102] In some embodiments, the frequency point of the backup communication channel corresponding to the backup communication channel information of each service is different from the frequency point of the main communication channel. It can be understood that the roadside device of the embodiment of the application includes multiple communication channels, and the multiple communication channels can include one main communication channel and one or more backup communication channels. The main communication channel is used for the roadside device to send a service announcement message to the vehicle-mounted device, and the backup communication channel is used for the roadside device to provide specific data services to the vehicle-mounted device. The information of the backup communication channel is different from the information of the main communication channel, and it can be understood that the frequency point corresponding to the backup communication channel is different from the frequency point corresponding to the main communication channel.

[0103] In this embodiment, the roadside device deploys at least two communication modules, and correspondingly, the vehicle-mounted device deploys at least two communication modules. In some optional embodiments, the communication module can be a C-V2X module. For example, when the roadside device and the vehicle-mounted device deploy two or more C-V2X modules, different C-V2X modules work at different frequency points, thereby establishing multiple communication channels on the roadside device. In some optional embodiments, the number of communication modules deployed by the roadside device is different from the number of communication modules deployed by the vehicle-mounted device. The number of communication modules deployed by the roadside device is related to the number of services it can provide, and the number of communication modules deployed by the vehicle-mounted device is related to the number of services it subscribes to. Generally, the number of communication modules deployed by the roadside device is greater than or equal to the number of communication modules deployed by the vehicle-mounted device.

[0104] In this embodiment, the roadside device sends a service announcement message through the main communication channel to announce the services provided by the roadside device to the vehicle-mounted device. The data services of vehicle-road cooperation provided by the roadside device to the vehicle-mounted device include but are not limited to file transmission services, high-precision dynamic map services, message set grouping services, etc.

[0105] In some implementations, the service information includes: at least one service identifier, service description information corresponding to each service, and backup communication channel identifier corresponding to each service; and / or, the channel information includes the following information of the backup communication channel corresponding to each service: backup communication channel identifier, backup communication channel frequency, and backup communication channel status information.

[0106] For example, the service announcement message proposed in this embodiment of the invention can be implemented in the DSA message or message frame of C-V2X communication technology. Figure 2 This is a schematic diagram illustrating the format of a service notification message provided in an embodiment of the present invention. Figure 2 As shown, a DSA message or message frame consists of a service announcement header and a service announcement application information section. The service announcement header includes a service announcement version field, a service announcement optional field indication / reservation field, a service announcement service notification message field, and a header extension field. The service announcement version field distinguishes different service announcement version numbers; the service announcement optional field indication / reservation field indicates whether a header extension field exists and whether it is extended; the service announcement service notification message field identifies the uniqueness of the service announcement service notification message; and the header extension field is reserved for other information. The service announcement application information section includes an application information count field, an application identifier field, and an application extension field. The application information count field represents the total number of application information items; the application identifier field distinguishes different application layer services; and the application extension field may include a first field indicating the message or message type, a second field storing service information (Service Info), and a third field storing channel information (Channel Info). The value or content of the first field indicates that the current message is a service announcement message.

[0107] In some implementations, the service information can be stored as an array, with a capacity equal to the total number of different data services that the roadside equipment can provide. This array is used to explain to the onboard equipment all the services that the roadside equipment can offer. The service information includes three parts: a service identifier, a service description, and a backup communication channel identifier corresponding to the service. The service identifier uniquely identifies each service; the service description is information describing the specific service content; and the backup communication channel identifier can be the number of the backup communication channel corresponding to each service.

[0108] Exemplarily, when the data services provided by the roadside device with the deployed C-V2X module for the vehicle-mounted device include the file transmission service, the high-precision dynamic map service, and the message set grouping service, the array capacity of the corresponding service information is 3; the service identifier can be the service number of each service, for example, the service number of the file transmission service can be 01, the service number of the high-precision dynamic map service can be 02, and the service number of the message set grouping service can be 03; the service description information can be a brief summary of the service content, for example, the description information of the file transmission service is: to transmit various files, the description information of the high-precision dynamic map service is: to provide high-precision road condition data, and the description information of the message set grouping service is: to send / detect different message sets for different groups; the corresponding backup communication channel identifier of the service can be the number of the backup communication channel where each service is located.

[0109] In some embodiments, the storage mode of the channel information can be an array form, and the array capacity is the total number of the CV2X modules deployed in the roadside device that can provide data services for vehicle-road cooperation, which is used to represent the related information of all backup communication channels in the roadside device. In the channel information, the following information of the backup communication channel corresponding to each service is included: the backup communication channel identifier, the frequency point of the backup communication channel, and the state information of the backup communication channel. The backup communication channel identifier is a unique identifier in the service information representing each backup communication channel corresponding to each service, and in the roadside device, one CV2X module can correspond to one service; the frequency point of the backup communication channel represents the frequency point of the CV2X module in the roadside device, or the frequency point of the backup communication channel corresponding to one service; and the state information of the backup communication channel represents the working state of the corresponding backup communication channel, or represents the working state of the corresponding CV2X module, which can include a service state (such as being in transmission / reception), a stop service state, and the like.

[0110] Exemplarily, when the roadside device with the deployed C-V2X module can provide red light information, monitoring information, and traffic event information, the array capacity of the corresponding channel information is 3, and in the channel information, the corresponding backup communication channel identifier, backup communication channel frequency point, and backup communication channel state are set for each C-V2X module in the roadside device.

[0111] In this embodiment, the roadside device can send the service announcement message through broadcasting on the main communication channel; the vehicle-mounted device currently in the main communication channel or working at the frequency point corresponding to the main communication channel can receive the service announcement message; and the roadside device waits to receive the service response message based on the service announcement message sent by the vehicle-mounted device after sending the service announcement message.

[0112] Step 102: receiving the service response message sent by the vehicle-mounted device. The service response message includes at least one service identifier and a first identifier corresponding to each service identifier, which indicates subscription or rejection of the service.

[0113] In the embodiment, the roadside device receives the service response message sent by the vehicle-mounted device on the main communication channel.

[0114] In the embodiment, the service response message represents the subscription of the vehicle-mounted device to at least one service provided by the roadside device, and specifically reflects the confirmation information of the vehicle-mounted device to the data service provided by the vehicle-road cooperative device in the roadside device. In some optional embodiments, the service response message includes at least one service identifier and a first identifier corresponding to each service identifier, which indicates subscription or rejection of the service; in other optional embodiments, the service response message can also include a device identifier, which is the identifier of the vehicle-mounted device sending the service response message, and can also be called the number of the vehicle-mounted device. For example, the device identifier of the vehicle-mounted device can be a unique identifier representing each vehicle-mounted device participating in subscription or rejection of the service.

[0115] Figure 3 The format of the service response message provided by the embodiment of the application is shown in the figure. Figure 3 As the data service method provided by the embodiment of the application is implemented by defining a new application extension field in the DSA message frame, the definition of the service announcement frame header part and the application information count field and the application identifier field in the service announcement application information part in the Figure 3 has no change, and has been described above, and will not be described here. In addition, Figure 3 The application extension field shown in the figure can include a first field indicating the type of message or message, a second field for storing the device identifier (Vehicle ID), a third field for storing the service identifier, and a fourth field for storing the first identifier indicating subscription or rejection of the service. The value or content of the first field is used to indicate that the current message is a service response message. The service identifier can also be called a service application identifier (SAID).

[0116] In some embodiments, the service identifier in the service response message is an identifier unique to each service provided by the roadside device; and the first identifier in the service response message corresponding to each service identifier represents the subscription status of each service, specifically reflecting whether the current service is subscribed by the vehicle-mounted device or rejected by the vehicle-mounted device, and each vehicle-mounted device participating in the subscription service or rejecting the subscription service needs to subscribe or reject the selection of all services provided in the service information. As an example, the first identifier can be a confirmation character represented by 0 or 1, for example, when the first identifier corresponding to the current service is displayed as 0, it means that the current vehicle-mounted device rejects to subscribe to the current service; when the first identifier corresponding to the current service is displayed as 1, it means that the current vehicle-mounted device subscribes to the current service.

[0117] In other embodiments, the service identifier in the service response message can also be an identifier unique to the service subscribed or confirmed by the vehicle-mounted device, that is, after receiving the service announcement message, the vehicle-mounted device can search for the service it needs or subscribes to according to the service provided by the roadside device in the service announcement message, and reply the identifier of the service it needs or subscribes to through the service response message; correspondingly, the first identifier in the service response message represents the subscription of the corresponding service.

[0118] The roadside device makes a response in step S103 according to the received service response message.

[0119] Step 103: Based on the service response messages of multiple vehicle-mounted devices, a first correspondence relationship between a first service and at least one vehicle-mounted device is established, the first identifier in the service response message corresponding to the at least one vehicle-mounted device indicates that the first service is subscribed, and the first service is any one of the at least one service.

[0120] In this embodiment, the roadside device can determine all vehicle-mounted devices that commonly subscribe to the first service based on the service response messages replied by multiple vehicle-mounted devices, that is, for the first service, a first correspondence relationship between the first service and at least one vehicle-mounted device is established. It can be understood that the roadside device can provide multiple services, and then based on the service response messages replied by all vehicle-mounted devices, all vehicle-mounted devices that subscribe to each service can be determined, and a first correspondence relationship between each service and at least one vehicle-mounted device is established, that is, the roadside device maintains or manages the service providing object in the form of a group.

[0121] In some embodiments, the first service corresponds to a service object group composed of at least one vehicle-mounted device that subscribes to the first service. As an example, the first correspondence relationship established for the first service can be represented as {service identifier: vehicle-mounted device 1, vehicle-mounted device 2, …, vehicle-mounted device n}.

[0122] In this embodiment, the first correspondence relationship established for the first service is used for the use of the subsequent service query message.

[0123] In this embodiment, for the roadside device, the first backup communication channel information corresponding to the first service is used for switching from the main communication channel to the first backup communication channel to provide the first service for the vehicle-mounted device subscribed to the first service. For the vehicle-mounted device, the first backup communication channel information corresponding to the first service is used for the vehicle-mounted device subscribed to the first service to switch to the first backup communication channel to use the first service.

[0124] In some optional embodiments of the present application, before step 101, the method further comprises: the roadside device determines the main communication frequency based on the main frequency point corresponding to the main communication channel; the roadside device selects the backup communication frequency corresponding to each service for the at least one service based on the main communication frequency and a preset frequency range, and determines the backup frequency point based on the backup communication frequency; the backup frequency point determined based on the backup communication frequency corresponding to each service is included in the backup communication channel information of each service.

[0125] In this embodiment, the roadside device determines the frequency point of the main communication channel before sending the service announcement message on the main communication channel, determines the main communication frequency according to the main frequency point, and selects the backup communication frequency corresponding to the first service based on the main communication frequency and a preset frequency range, and determines the backup frequency point corresponding to the first service according to the backup communication frequency.

[0126] In this embodiment, the main frequency point can determine the main communication frequency, and the main frequency point and the main communication frequency are the frequency point and the communication frequency of the main communication channel. The main frequency point can be pre-set based on the frequency band of network deployment or pre-configured by the network device. The backup frequency point can be calculated based on the number of services that can be provided by the roadside device, the main communication frequency corresponding to the main frequency point, and the backup communication frequency selected in the preset frequency range. The backup frequency point can determine the backup communication frequency, and the backup frequency point and the backup communication frequency are the frequency point and the communication frequency of the backup communication channel. That is, the main frequency point and the backup frequency point are related to the main communication frequency and the backup communication frequency respectively, that is, each frequency point has a communication channel frequency corresponding thereto, and the conversion method of the frequency point and the frequency is shown in formula (1).

[0127] As an example, the preset frequency range can be the 5905MHz-5925MHz frequency band allocated to C-V2X use in the frequency planning of the Internet of Vehicles, and the frequency conversion of the frequency points of the main communication channel and the backup communication channel of C-V2X can be set by the following formula:

[0128] F DL = F DL_low + 0.1*(N DL - N offs_DL ) (1)

[0129] wherein F DL is the carrier frequency downlink frequency; F DL_low is the lowest uplink frequency corresponding to the frequency band of the frequency point; N DL is the carrier frequency downlink frequency point; N offs_DL is the highest downlink frequency point corresponding to the frequency band of the frequency point; according to the provisions of the E-UTRA frequency band frequency point table (not shown), each carrier frequency downlink frequency point has a lowest uplink frequency and a highest downlink frequency corresponding to the frequency band.

[0130] Exemplarily, the frequency point of the communication channel can be set based on the provisions of C-V2X "new four-cross", when the frequency point of the main communication channel is set to 55140, the calculation process of the corresponding main frequency is as follows:

[0131] N DL - N offs_DL = 600 (2)

[0132] 0.1 * (N DL - N offs_DL ) = 0.1 * 600 (3)

[0133] F DL = F DL_low + 0.1 * (N DL - N offs_DL ) = 5855 + 60 = 5915 (4)

[0134] wherein, first, calculate the frequency point difference between the set carrier frequency downlink frequency point and the highest downlink frequency point corresponding to the frequency band of the frequency point, based on the E-UTRA frequency band frequency point table, the frequency band of the carrier frequency downlink frequency point 55140 is 54540-55239, the corresponding highest downlink frequency is 54540, the corresponding lowest uplink frequency is 5855, the calculation process is shown in formula (2); Then multiply the frequency point difference obtained by the above calculation by 0.1, the calculation process is shown in formula (3); Finally, sum the result obtained by the above and the lowest uplink frequency corresponding to the frequency band of the carrier frequency downlink frequency point to obtain the frequency corresponding to the set carrier frequency downlink frequency point, the calculation process is shown in formula (4), which can be understood as when the frequency point of the main communication channel is set to 55140, the main frequency corresponding to the main communication channel is 5915MHz.

[0135] Exemplarily, when setting up a backup communication frequency in the frequency band used by C-V2X, the corresponding backup communication frequency can be determined according to the main communication frequency and the preset frequency range, and then the inverse operation is performed based on the frequency point frequency conversion formula (1) to calculate the backup frequency point corresponding to the set backup communication frequency, which will not be described in detail here. For example, 5920 is selected as a backup communication frequency, and the backup frequency point is calculated to be 55190 by reverse calculation. Thus, the roadside device can determine the backup frequency point corresponding to each backup communication channel.

[0136] In some embodiments of the present application, the method further comprises: the roadside device sending a service query message through the first backup communication channel corresponding to the first service, the service query message being used to confirm whether the vehicle-mounted device subscribed to the first service switches to access the first backup communication channel; and the roadside device judging whether a service reply message sent by the vehicle-mounted device is received, wherein if the service reply message sent by the vehicle-mounted device is received, it is determined that the vehicle-mounted device switches to access the first backup communication channel, and if the service reply message sent by the vehicle-mounted device is not received, it is determined that the vehicle-mounted device does not switch to access the first backup communication channel.

[0137] In the present embodiment, before sending the service query message for the first service, the roadside device first switches to access the first backup communication channel corresponding to the first service, and sends the service query message to the vehicle-mounted device on the first backup communication channel.

[0138] In the present embodiment, the roadside device can broadcast the service query message for the first service through the first backup communication channel; according to different types of service query messages, at least part of the vehicle-mounted devices subscribed to the first service can switch to access the first backup communication channel corresponding to the first service according to the information carried in the service announcement, and at least part of the vehicle-mounted devices switched to the first backup communication channel can receive the service query message sent by the roadside device.

[0139] In the present embodiment, the method for the roadside device to judge whether the vehicle-mounted device subscribed to the first service switches to access the first backup communication channel is that if the service reply message sent by the vehicle-mounted device is received, it is determined that the vehicle-mounted terminal has switched to access the first backup communication channel, and if the service reply message sent by the vehicle-mounted device is not received, it is determined that the vehicle-mounted device does not switch to access the first backup communication channel.

[0140] It can be understood that when the roadside device providing the first service and the vehicle-mounted device subscribed to the first service both switch to access the first backup communication channel, the vehicle-mounted device can receive the service query message sent by the roadside device and reply, and the roadside device can receive the service reply message sent by the vehicle-mounted device.

[0141] In some embodiments, the service query message comprises: a device identification field for identifying at least one vehicle-mounted device corresponding to the first service, a service identification field for identifying the first service, and a service state field for identifying a service state.

[0142] In this embodiment, the service query message represents the switching access situation of the vehicle-mounted device subscribed to the first service to the first backup communication channel, and specifically can query whether all vehicle-mounted devices subscribed to the first service switch to access the first backup communication channel, and can also specify whether at least one vehicle-mounted device switches to access the first backup communication channel. Figure 4 The structure of the service query message provided by the embodiment of the application is shown in the figure. Figure 4 As the data service method provided by the embodiment of the application is implemented by defining an application extension field in the service announcement application information part of the DSA message or frame, the definition of the service announcement frame header part and the application information count field and the application identification field in the service announcement application information part in the Figure 4 application information count field and the application identification field in the service announcement application information part in the Figure 4 application information count field and the application identification field in the service announcement application information part in the

[0143] application information count field and the application identification field in the service announcement application information part in the

[0144] As an example, the device identification of the vehicle-mounted device can be a preset number of the vehicle-mounted device, and the service identification can be a preset service number.

[0145] In some embodiments, when the values of the device identification fields in the service query message are all set as the first value, the service query message is used to confirm whether all vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel; when the values of the device identification fields in the service query message are not all the first value, the service query message further includes the device identification of a specific vehicle-mounted device, and the service query message is used to confirm whether the specific vehicle-mounted device subscribing to the first service switches to access the first backup communication channel.

[0146] In the embodiment, the service query message can include two types, one is a general type, i.e., querying all vehicle-mounted devices subscribing to the first service. As an example, taking 1 as the first value, when the values of the device identification fields in the service query message are all set as 1, it represents that the current query initiated by the roadside device is a general query, and all vehicle-mounted devices subscribing to the first service need to send a service reply message based on the service query message. The other type of the service query message is a specified query, i.e., querying a specific vehicle-mounted device subscribing to the first service. As another example, taking 1 as the first value, when the values of the device identification fields in the service query message are not all 1, i.e., there are other values, it represents that the current query initiated by the roadside device is a specified query or a specific query, and the specific vehicle-mounted device corresponding to the field value of the specified device identification or the specific device identification sends a service reply message based on the service query message to determine the service state of the specific vehicle-mounted device. In the service query message of the specified query type, the service query message can further include the device identification of the specific vehicle-mounted device queried. In some optional embodiments, the other values in the device identification field which are not the first value can be the device identification of the specific vehicle-mounted device.

[0147] Based on the above service query message and the corresponding service reply message, the roadside device can determine the vehicle-mounted device subscribing to the first service and having switched to access the first backup communication channel, and then can perform data transmission according to the first backup communication channel.

[0148] For large file data to be transmitted, the embodiment of the present application provides a data transmission scheme to realize the transmission of large file data in the V2X broadcast channel in the manner of facing a service object group. Similarly, based on the application extension field of the application information of the service announcement of the DSA message or the message frame, the transmission of large file data in the V2X broadcast channel in the manner of facing a service object group is realized.

[0149] In some embodiments, Figure 5 A flowchart of file transmission in the data service method of the embodiment of the present application is shown. In the embodiment, the roadside device providing the first service transmits the to-be-transmitted data corresponding to the first service through the first backup communication channel, as shown in FIG. 4. Figure 5As shown, the specific process will be described according to the following steps.

[0150] Step 201: After the block processing of the to-be-transmitted data, a file service start message is sent. The file service start message includes the related information of the to-be-transmitted data.

[0151] Step 202: A first file service transmission message is sent through the first backup communication channel. The first file service transmission message includes a first file block identifier and a file block corresponding to the first file block identifier.

[0152] Step 203: A first file block response message sent by the vehicle-mounted device is received. The first file block response message at least includes a received first file block identifier.

[0153] Step 204: After the transmission of the to-be-transmitted data is completed, a transmission completion notification message sent by the vehicle-mounted device is received.

[0154] In this embodiment, before step 201 is performed, for large file data that needs to be transmitted to the vehicle-mounted device, the roadside device can download the complete file of the to-be-transmitted data through the optical fiber network. After the roadside device receives the complete file of the to-be-transmitted data, the to-be-transmitted data is first processed in blocks.

[0155] As an example, if the file size is X bytes, limited by the transmission capacity of the communication channel for the maximum packet length, 4096 bytes can be set as a unit, and the file is logically divided into X / 4096 file blocks. It can be understood that the total number of file blocks is X / 4096.

[0156] In this embodiment, the roadside device sends a file service start message to the vehicle-mounted device through the first backup communication channel to indicate the related information of the to-be-transmitted file to the vehicle-mounted device. In other optional embodiments, the file service start message can also include the device identifier of the vehicle-mounted device.

[0157] In some embodiments, the related information of the to-be-transmitted data at least includes: a file name (FileName), a file block size, a file block quantity, and file verification information. In other optional embodiments, the related information of the to-be-transmitted data can also include a file size, which can represent the total file size of the to-be-transmitted data.

[0158] In this embodiment, the file verification information can be message-digest algorithm 5 (MD5) verification information, which is used to check the correctness of the received transmission data.

[0159] Figure 6 The format of the file service start message provided by the embodiment of the present application is shown in the following figure:Figure 6 As shown, the data service method provided by the embodiment of the present application is realized by defining the application extension field in the service announcement application information part in the new DSA message or frame, thus Figure 6 The definition of the application information count field and the application identification field in the service announcement frame header part and the service announcement application information part in the message or frame is not changed, and has been described above, and will not be described here again. In addition, Figure 6 The application extension field can include a first field indicating the type of the message or frame, a second field for storing the file name, a third field for storing the total number of file blocks, a fourth field for storing the device identification, and a fifth field for storing the file check information; wherein the value or content of the first field is used to indicate that the current message is a file service start message.

[0160] Exemplarily, the file name can be characters related to the data to be transmitted; the total number of file blocks indicates the total number of file blocks obtained by dividing the complete file of the data to be transmitted into fixed bytes; and the device identification of the vehicle-mounted device can be the number of the vehicle-mounted device.

[0161] In the embodiment, after the roadside device sends the file service start message to the vehicle-mounted device through the first backup communication channel, the roadside device continues to send the first file service transmission message on the first backup communication channel, and the first file service transmission message includes the file blocks to be transmitted, so as to transmit the data through the first file service transmission message.

[0162] As an example, the roadside device can read the file blocks in the order of the file block identification, and when the kth file block in the data to be transmitted is read, the position pointer address of the kth file block needs to be recorded. Wherein, the roadside device can mark the file block identification for each file block after the data to be transmitted is divided into blocks; for example, the roadside device can first read the file block with the file block identification 1, and transmit the file block with the file block identification 1 through the first file service transmission message; after the file block with the file block identification 1 is successfully transmitted, the file block with the file block identification 2 is transmitted through the second file service transmission message, and so on. It should be noted that, in the embodiment of the present application, the file blocks are transmitted through the file service transmission message, so as to continuously transmit two file blocks (for example, the first file block corresponding to the first file block identification and the second file block corresponding to the second file block identification). The file service transmission message used for transmitting the first file block is recorded as the first file service transmission message, and the file service transmission message used for transmitting the second file block is recorded as the second file service transmission message.

[0163] Figure 7 The format of the file service transmission message provided by the embodiment of the present application is shown in the following figure: Figure 7As shown, the data service method provided by the embodiment of the present application is realized by defining an application extension field in the service announcement application information part of the DSA message or frame, and thus Figure 7 The definitions of the application information count field and the application identification field in the service announcement frame header part and the service announcement application information part in the DSA message are not changed, and have been described above, and thus will not be described again here. In addition, Figure 7 As shown, the application extension field can include a first field indicating the type of the message or frame, a second field for storing the file block identification, a third field for storing the device identification, and a fourth field for storing the file block byte stream; the value or content of the first field is used to indicate that the current message is a file service start message.

[0164] For example, the file block identification can be a number based on the transmission order of the file block, or a number set for each file block in the process of dividing the data to be transmitted; the file block byte stream indicates the file block corresponding to the file block identification, and in this example, can indicate the file block corresponding to the first file block identification; the device identification of the vehicle-mounted device can be a preset number of the vehicle-mounted device.

[0165] In this embodiment, after the road test device sends the file service transmission message, it waits for all vehicle-mounted devices subscribed to the first service to reply the file block acknowledgement message, wherein the file block acknowledgement message is used to indicate that the corresponding vehicle-mounted device has received the file block carried by the file service transmission message.

[0166] In this embodiment, the road side device receives the first file block acknowledgement message sent by the vehicle-mounted device subscribed to the first service, which is used to confirm that the current vehicle-mounted device has received the file block corresponding to the first file block identification, and the first file block acknowledgement message at least includes the received first file block identification. Figure 8 The format of the file block acknowledgement message provided by the embodiment of the present application is shown in the following figure: Figure 8 As shown, the data service method provided by the embodiment of the present application is realized by defining an application extension field in the service announcement application information part of the DSA message or frame, and thus Figure 8 The definitions of the application information count field and the application identification field in the service announcement frame header part and the service announcement application information part in the DSA message are not changed, and have been described above, and thus will not be described again here. In addition, Figure 8 As shown, the application extension field can include a first field indicating the type of the message or frame, a second field for storing the file block identification, and a third field for storing the device identification; the value or content of the first field is used to indicate that the current message is a file service start message.

[0167] Exemplarily, the file block identifier can be a number based on a file block transmission sequence, or a number set for each file block in a process of blocking the data to be transmitted; and the device identifier of the vehicle-mounted device can be a preset number of the vehicle-mounted device.

[0168] In the embodiment, after the roadside device receives the first file block reply messages replied by all the vehicle-mounted devices subscribing to the first service, the roadside device finds the position pointer address of the file block corresponding to the first file block identifier, and continues to transmit the file block corresponding to the second file block identifier.

[0169] In some embodiments, the roadside device receives the first file block reply message sent by the vehicle-mounted device, including: the roadside device starts a timer after sending the first file service transmission message, and receives the first file block reply message sent by the vehicle-mounted device within the timing range of the timer.

[0170] As an example, the timing range of the timer can be set to 5 seconds, and the roadside device starts a 5-second timer after sending the first file service transmission message, to determine whether the file block corresponding to the first file block identifier is successfully transmitted.

[0171] In the embodiment, whether the first file block reply message replied by the vehicle-mounted device is received within the timing range of the timer can be used to determine whether the file block corresponding to the first file block identifier is successfully transmitted.

[0172] In some embodiments, the method further includes: if the roadside device receives the first file block reply message sent by all the vehicle-mounted devices subscribing to the first service within the timing range of the timer, then continuing to send a second file service transmission message through the first backup communication channel, and the second file service transmission message includes a second file block identifier and a file block corresponding to the second file block identifier.

[0173] In this embodiment, the roadside device receives the first file block reply message replied by the vehicle-mounted device within the timing range of the timer, indicating that the transmission of the file block corresponding to the first file block identifier is successful for the vehicle-mounted device. Correspondingly, if the roadside device receives all the first file block reply messages replied by the vehicle-mounted devices within the timing range of the timer, it indicates that the transmission of the file block corresponding to the first file block identifier is successful for all the vehicle-mounted devices subscribing to the first service. As an example, the roadside device can compare the device identifiers of the vehicle-mounted devices sending the file block reply message based on the first correspondence relationship, and after confirming that the vehicle-mounted devices sending the file block reply message are consistent with the vehicle-mounted devices subscribing to the first service, the roadside device determines that all the vehicle-mounted devices reply the first file block reply message, and can continue to transmit the second file block, i.e., the vehicle-mounted devices continue to send the second file service transmission message through the first backup communication channel, and the second file service transmission message includes the second file block identifier and the file block corresponding to the second file block identifier.

[0174] As an example, after sending the first file service transmission message, the roadside device starts a 5-second timer. If the roadside device receives the first file block reply message sent by all the vehicle-mounted devices subscribing to the first service within 5 seconds, it indicates that all the vehicle-mounted devices successfully receive the file block corresponding to the current first file block identifier, and the transmission of the second file block continues.

[0175] In some embodiments, the method further includes: if the roadside device does not receive the first file block reply message sent by any vehicle-mounted device subscribing to the first service within the timing range of the timer, re-sending the service query message through the first backup communication channel, the service query message being used to confirm whether all the vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel; and confirming that the data transmission fails when the roadside device does not receive the service reply message sent by any vehicle-mounted device.

[0176] In this embodiment, the roadside device does not receive the first file block reply message replied by any vehicle-mounted device within the timing range of the timer, indicating that the data transmission of all the vehicle-mounted devices subscribing to the first service fails, which may be due to the interruption of communication between the roadside device and the vehicle-mounted device based on the first backup communication channel. Therefore, the service query message (general query) and the service reply message can be used to determine whether all the vehicle-mounted devices access the first backup communication channel.

[0177] As an example, after sending the first file service transmission packet, the roadside device starts a 5-second timer. If no file service response packet is received from all the vehicle-mounted devices that have subscribed to the first service within 5 seconds, the roadside device re-sends the service query packet to the vehicle-mounted devices through the first backup communication channel, and re-confirms whether all the vehicle-mounted devices that have subscribed to the first service have switched to access the first backup communication channel by initiating a general query.

[0178] In some other embodiments, the method further comprises: if, within the timing range of the timer, the roadside device does not receive the first file block response packet sent by the first vehicle-mounted device that has subscribed to the first service, re-sending the service query packet through the first backup communication channel, the service query packet being used to confirm whether the first vehicle-mounted device has switched to access the first backup communication channel; the first vehicle-mounted device being any one of all the vehicle-mounted devices that have subscribed to the first service; if the roadside device does not receive the service reply packet sent by the first vehicle-mounted device of the part of the vehicle-mounted devices, determining that the first vehicle-mounted device has left the first correspondence; and if the roadside device receives the service reply packet sent by the second vehicle-mounted device of the part of the vehicle-mounted devices, re-sending the first file service transmission packet through the first backup communication channel.

[0179] In this embodiment, there is at least one first vehicle-mounted device that has subscribed to the first service and has not sent the first file block response packet to the roadside device.

[0180] As an example, after sending the first file service transmission packet, the roadside device starts a 5-second timer. If no file block response packet is received from the first vehicle-mounted device that has subscribed to the first service within 5 seconds, the roadside device re-sends the service query packet to the vehicle-mounted devices through the first backup communication channel (designated query), and re-confirms whether the first vehicle-mounted device that has not sent the file block response packet among the vehicle-mounted devices that have subscribed to the first service has switched to access the first backup communication channel by initiating a designated query. If no service reply packet is received from the first vehicle-mounted device, it can be determined that the first vehicle-mounted device has left the first correspondence. The reason for leaving the first correspondence can be that the first vehicle-mounted device has not switched to access the first backup communication channel, or that the first vehicle-mounted device has cancelled the first service, and the roadside device can remove the first vehicle-mounted device from the first correspondence. If the service reply packet sent by the first vehicle-mounted device is received, it indicates that the first vehicle-mounted device has switched to access the first backup communication channel, but a file block transmission error occurs during the file block transmission. Therefore, the first file service transmission packet is re-sent through the first backup communication channel, which is used to re-transmit the file block corresponding to the current first file block identifier, to solve the file block transmission error problem, so as to realize the breakpoint resume of the file block.

[0181] In the embodiment, after the roadside device transmits the last file block, the roadside device waits for the vehicle-mounted device to send a transmission completion notification message. The transmission completion notification message is used to indicate to the roadside device that the vehicle-mounted device has confirmed receipt of all file blocks. After receiving the transmission completion notification message sent by the vehicle-mounted device, the file is confirmed to be legal, and the data transmission is ended.

[0182] Figure 9 Flowchart of the data service method of the embodiment Figure 2 ; as Figure 9 shown, the method comprises:

[0183] Step 301: The vehicle-mounted device receives a service notification message sent by the roadside device through a main communication channel. The service notification message includes service information and channel information. The service notification message is used to notify the vehicle-mounted device of at least one service provided and the corresponding backup communication channel information of each service. The frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel.

[0184] In some embodiments, the main communication channel can be a main communication channel of any vehicle wireless communication technology. The vehicle-mounted device and the roadside device interact through the same main communication channel. For example, the main communication channel can be a C-V2X-based main communication channel.

[0185] In some embodiments, the frequency point of the backup communication channel corresponding to the backup communication channel information of each service is different from the frequency point of the main communication channel. It can be understood that the roadside device of the embodiment includes multiple communication channels. The multiple communication channels can include one main communication channel and one or more backup communication channels. The main communication channel is used for the vehicle-mounted device to receive the service notification message sent by the roadside device. The backup communication channel is used for the vehicle-mounted device to implement the subscribed specific data service. The information of the backup communication channel is different from the information of the main communication channel. It can be understood that the frequency point corresponding to the backup communication channel is different from the frequency point corresponding to the main communication channel.

[0186] In the embodiment, the vehicle-mounted device deploys at least two communication modules, and correspondingly, the roadside device deploys at least two communication modules. In some optional embodiments, the communication module can be a C-V2X module. For example, when the vehicle-mounted device and the roadside device deploy two or more C-V2X modules, different C-V2X modules work at different frequency points, thereby establishing multiple communication channels on the vehicle-mounted device. In some optional embodiments, the number of communication modules deployed by the vehicle-mounted device is different from the number of communication modules deployed by the roadside device. The number of communication modules deployed by the vehicle-mounted device is related to the number of services subscribed by the vehicle-mounted device, and the number of communication modules deployed by the roadside device is related to the number of services provided by the roadside device. Generally, the number of communication modules deployed by the vehicle-mounted device is less than or equal to the number of communication modules deployed by the roadside device.

[0187] In the embodiment, the roadside device sends a service announcement message on the main communication channel, and the vehicle-mounted device receives the service announcement message on the main communication channel. The service announcement message is used to announce the services provided by the roadside device to the vehicle-mounted device. The data services of vehicle-road cooperation provided by the roadside device for the vehicle-mounted device include but are not limited to file transmission services, high-precision dynamic map services, message set grouping services, etc.

[0188] In some embodiments, the service information includes at least one service identifier, service description information corresponding to each service, and backup communication channel identifier corresponding to each service; and / or the channel information includes the following information of the backup communication channel corresponding to each service: backup communication channel identifier, frequency point of the backup communication channel, and state information of the backup communication channel.

[0189] For example, the service announcement message provided by the embodiment of the application can be implemented in a DSA message or message frame belonging to the C-V2X communication technology. The format of the service announcement message provided by the embodiment of the application is shown in FIG. 2. The specific description of the service information and the channel information is consistent with the description of the service information and the channel information in the method applied to the roadside device, which will not be described in detail here. Figure 2

[0190] In the embodiment, after receiving the service announcement message, the vehicle-mounted device sends a service response message related to the first service subscribed by the vehicle-mounted device to the roadside device through the main communication channel based on the received service announcement message.

[0191] ​Step 302: The vehicle-mounted device determines the first service to be subscribed and the first backup communication channel information corresponding to the first backup communication channel corresponding to the first service according to the service information and the channel information, and sends a service response message to the roadside device. The service response message includes at least one service identifier and a first identifier corresponding to each service identifier indicating subscription service or rejection of subscription service. The first backup communication channel information is used for the vehicle-mounted device to switch to the first backup communication channel to use the first service.

[0192] Here, the vehicle-mounted device sends the service response message to the roadside device on the main communication channel.

[0193] In some embodiments, the vehicle-mounted device determines the first service to be subscribed and the first backup communication channel information corresponding to the first backup communication channel corresponding to the first service according to the service information and the channel information, including: the vehicle-mounted device determines the first service to be subscribed according to the service information, finds the service information according to the identifier of the first service, and determines the first backup communication channel identifier corresponding to the first service; find the channel information according to the first backup communication channel identifier, obtain the first backup communication channel information corresponding to the first backup communication channel identifier, and the first backup communication channel information includes the frequency point of the backup communication channel and the state information of the backup communication channel.

[0194] In this embodiment, for the vehicle-mounted device, the first backup communication channel information corresponding to the first service is used for the vehicle-mounted device subscribed to the first service to switch from the main communication channel to the first backup communication channel to use the first service. For the roadside device, the first backup communication channel information corresponding to the first service is used to switch from the main communication channel to the first backup communication channel to provide the first service for the vehicle-mounted device subscribed to the first service.

[0195] As an example, after receiving the service channel message sent by the roadside device, the vehicle-mounted device determines at least one first service to be subscribed in the service information in the service announcement message according to the current demand of the vehicle-mounted device, determines the frequency point of the first backup communication channel and the state information of the first backup communication channel in the channel information through the first backup communication channel identifier corresponding to the first service in the service information, so that the subsequent vehicle-mounted device can switch to the first backup communication channel according to the frequency point of the first backup communication channel.

[0196] In the embodiment, the main frequency point can determine the main communication frequency, and the main frequency point and the main communication frequency are the frequency point and the communication frequency of the main communication channel. The main frequency point can be pre-set based on the frequency band of network deployment or pre-configured by the network device. The backup frequency point can be calculated based on the number of services that can be provided by the road side device, the main communication frequency corresponding to the main frequency point, and the backup communication frequency selected in the preset frequency range. The backup frequency point can determine the backup communication frequency, and the backup frequency point and the backup communication frequency are the frequency point and the communication frequency of the backup communication channel. Each backup communication channel corresponds to a service, and the backup communication frequency is selected in the preset frequency range based on the number of data services provided by the vehicle-mounted device. According to each backup communication frequency, the corresponding backup frequency point can be determined. The conversion method of the frequency point and the frequency is shown in formula (1). The specific description of the frequency point and the frequency conversion method is consistent with the description of the frequency point and the frequency conversion method in the foregoing method applied to the road side device, and will not be described here.

[0197] As an example, after the vehicle-mounted device deployed with the C-V2X module receives the service announcement message sent by the road side device in the main communication channel of C-V2X, all services provided by the road side device deployed with the C-V2X module are parsed. For at least one first service determined to be subscribed, the driver can interact with the vehicle-mounted terminal (for example, a vehicle-mounted PAD display screen) connected to the vehicle-mounted device, and complete the subscription of the first service through the operation of the user, and then send the service response message containing at least one first service determined to be subscribed to the road side device in the main communication channel of C-V2X. In other optional embodiments, the vehicle-mounted device can also determine the services corresponding to each C-V2X module according to the deployed C-V2X module, and then determine at least one first service to be subscribed according to the logic of the vehicle-mounted device, and then send the service response message containing at least one first service determined to be subscribed to the road side device in the main communication channel of C-V2X.

[0198] In some embodiments, the service response message represents the subscription of the vehicle-mounted device to the services provided by the road side device, and specifically reflects the confirmation information of the vehicle-mounted device to the data services provided by the vehicle-road cooperation device in the road side device. In some optional embodiments, the service response message includes at least one service identifier and a first identifier corresponding to each service identifier indicating subscription to the service or refusal to subscribe to the service. In other optional embodiments, the service response message can also include a device identifier, which is the identifier of the vehicle-mounted device sending the service response message, and can also be called the number of the vehicle-mounted device. For example, the device identifier of the vehicle-mounted device can be a unique identifier representing each vehicle-mounted device participating in the subscription service or refusing to subscribe to the service.

[0199] The format diagram of the service response message provided by the embodiment of the application is as follows: Figure 3As shown, the specific description of the service response packet is consistent with the description of the service response packet in the foregoing method applied to the roadside device, and thus is not described herein again.

[0200] In some embodiments, the method further includes: switching, by the vehicle-mounted device, to the first backup communication channel based on the first backup communication channel information.

[0201] In this embodiment, the vehicle-mounted device subscribed to the first service switches to the first backup communication channel based on the first backup communication channel frequency point after determining the first backup communication channel frequency point and the state information of the first backup communication channel, and is used for packet interaction of the first service with the roadside device.

[0202] In some embodiments, the method further includes: receiving, by the vehicle-mounted device, a service query packet sent by the roadside device through the first backup communication channel, the service query packet being used to confirm whether the vehicle-mounted device subscribed to the first service switches to the first backup communication channel; and sending, by the vehicle-mounted device, a service reply packet to the roadside device.

[0203] In this embodiment, the vehicle-mounted device sends a service reply packet to the roadside device according to the access condition of the received first backup communication channel corresponding to the first service after receiving the service query packet sent by the roadside device.

[0204] In this embodiment, if the vehicle-mounted device has switched to the first backup communication channel, the service query packet sent by the roadside device through the first backup communication channel can be received, and a service reply packet can be sent to the roadside device; if the vehicle-mounted device has not switched to the first backup communication channel, the service query packet sent by the roadside device through the first backup communication channel cannot be received, and a service reply packet cannot be sent to the roadside device.

[0205] In some embodiments, the service query packet includes: a device identification field used to identify at least one vehicle-mounted device corresponding to the first service, a service identification field used to identify the first service, and a service state field used to identify a service state.

[0206] The format of the service query packet provided by the embodiment of the application is shown in Figure 4 As shown, the specific description of the service query packet is consistent with the description of the service query packet in the foregoing method applied to the roadside device, and thus is not described herein again.

[0207] In some embodiments, when the values of all the device identification fields in the service query message are set as the first value, the service query message is used to confirm whether all the vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel; when the values of the device identification fields in the service query message are not all the first value, the service query message further includes the device identification of a specific vehicle-mounted device, and the service query message is used to confirm whether the specific vehicle-mounted device subscribing to the first service switches to access the first backup communication channel.

[0208] In the embodiment, the service query message can include two types, one is a general type, i.e., querying all vehicle-mounted devices subscribing to the first service. As an example, taking 1 as the first value, when the values of all the device identification fields in the service query message are set as 1, it indicates that the service query message received by the vehicle-mounted device currently subscribing to the first service is a general query, and the current vehicle-mounted device needs to send a service reply message based on the service query message. The other type of the service query message is a specified query, i.e., querying a specific vehicle-mounted device subscribing to the first service. As another example, taking 1 as the first value, when the values of all the device identification fields in the service query message are not all 1, i.e., there are other values, it indicates that the service query message received by the vehicle-mounted device currently subscribing to the first service is a specified query or a specific query, and the current vehicle-mounted device needs to first determine whether it is the vehicle-mounted device specified in the service query message. In the service query message of the specified query type, the service query message can further include the device identification of the specific vehicle-mounted device queried. Then, the vehicle-mounted device can determine whether the device identification of the specific vehicle-mounted device includes its own device identification, if yes, it indicates that the vehicle-mounted device is the specific vehicle-mounted device, and needs to send a service reply message based on the service query message for the roadside device to determine the state of the specific vehicle-mounted device; if not, it indicates that the vehicle-mounted device is not the specific vehicle-mounted device, and does not need to send a service reply message.

[0209] Based on the above service query message and the corresponding service reply message, the roadside device can determine the vehicle-mounted device subscribing to the first service and having switched to access the first backup communication channel, and then can perform data transmission according to the first backup communication channel.

[0210] For large file data that needs to be transmitted, the embodiment of the application provides a data transmission scheme to realize the transmission of large file data in a service object group manner in the V2X broadcast channel. Similarly, based on the application extension field of the service announcement application information of the DSA message or message frame, the large file data transmission in the service object group manner in the V2X broadcast channel is realized.

[0211] Figure 10A flowchart of a file transmission method applied to a vehicle-mounted device is shown. In this embodiment, a roadside device providing a first service sends data corresponding to the first service to the vehicle-mounted device via a first backup communication channel. Figure 10 The specific process will be described according to the following steps.

[0212] Step 401: The vehicle-mounted device receives a file service start message sent by the roadside device via the first backup communication channel. The file service start message includes information about the data to be transmitted.

[0213] Step 402: The vehicle-mounted device receives a first file service transmission message sent by the roadside device via the first backup communication channel. The first file service transmission message includes a first file block identifier and a file block corresponding to the first file block identifier.

[0214] Step 403: The vehicle-mounted device sends a first file block response message to the roadside device. The first file block response message includes at least the first file block identifier that has been received.

[0215] In this embodiment, after the vehicle-mounted device subscribed to the first service switches to access the first backup communication channel, the vehicle-mounted device receives a file service start message sent by the roadside device via the first backup communication channel, so as to explicitly determine the information about the data to be transmitted corresponding to the first service. In other optional embodiments, the file service start message can also include a device identifier of the vehicle-mounted device.

[0216] In some embodiments, the information about the data to be transmitted includes at least a file name, a file block size, a file block quantity, and file verification information.

[0217] As an example, the file verification information can be MD5 verification information, which is used to check the correctness of the received transmission data.

[0218] In this embodiment, the vehicle-mounted device can explicitly determine the file name, the file block quantity, the byte size corresponding to the file block, and the file verification information used to check the correctness of the received transmission data by receiving the information about the data to be transmitted sent by the roadside device. In addition, the information about the data to be transmitted can also include a file size, which can represent the total file size of the data to be transmitted. It should be noted that the roadside device first performs block processing on the complete file after receiving the complete file.

[0219] As an example, the file block can be obtained by equally dividing the complete file by the roadside device in fixed bytes.

[0220] For example, if the file size is X bytes, the file can be logically divided into X / 4096 file blocks with 4096 bytes as a unit, and the total number of file blocks is X / 4096.

[0221] A format diagram of the file service start message provided by the embodiment of the application is shown in Figure 6 The specific description of the file service start message is consistent with the description of the file service start message in the foregoing method applied to the roadside device, and will not be described in detail here.

[0222] In the embodiment, the vehicle-mounted device subscribed to the first service receives the first file service transmission message sent by the roadside device on the first backup communication channel after receiving the file service start message sent by the roadside device, and the first file service transmission message carries the file block.

[0223] A format diagram of the file service transmission message provided by the embodiment of the application is shown in Figure 7 The specific description of the file service transmission message is consistent with the description of the file service transmission message in the foregoing method applied to the roadside device, and will not be described in detail here.

[0224] As an example, after receiving the first file service transmission file, the vehicle-mounted device explicitly identifies the received first file block, writes the file block corresponding to the first file block identifier into the file, waits to receive the second file block in the second file service transmission message sent by the roadside device, and sends the first file block response message to the roadside device through the first backup communication channel to inform the roadside device that the current vehicle-mounted device has confirmed the reception of the first file block.

[0225] A format diagram of the file block response message provided by the embodiment of the application is shown in Figure 8 The specific description of the file block response message is consistent with the description of the file block response message in the foregoing method applied to the roadside device, and will not be described in detail here.

[0226] In some embodiments, the method further comprises: after the transmission of the to-be-transmitted data is completed, the vehicle-mounted device performs verification according to the to-be-transmitted data and file verification information, and sends a transmission completion notification message to the roadside device after the verification is passed.

[0227] Exemplarily, after the X / 4096th file block identification corresponding to the file block received by the vehicle-mounted device is written into the file, the correctness of all the received file blocks is checked based on the file MD5 check information in the received file service start message, the received file blocks are integrated and MD5 operation is performed, and the operation result is compared with the file MD5 check information of the data to be transmitted in the file service start message. If the results are consistent, it indicates that the file block transmission is complete, thereby passing the check, and a transmission completion notification message can be sent to the roadside device.

[0228] In some embodiments, the method further comprises: after the first service ends, if it is confirmed that there is no other service on the first backup communication channel, the vehicle-mounted device switches back to the main communication channel from the first backup communication channel.

[0229] In this embodiment, after the vehicle-mounted device deployed with the C-V2X module completes the file check, it is confirmed that there is no other ongoing service on the first backup communication channel, the first backup communication channel corresponding to the vehicle-mounted device is switched back to the main communication channel corresponding to the C-V2X main frequency point, and the basic data service interaction of C-V2X is continued in the C-V2X main communication channel.

[0230] In this embodiment, by deploying the large file data transmission protocol on multiple C-V2X communication channels, the roadside device has higher efficient complete file transmission capability when transmitting large file data to the vehicle-mounted device. And when the data transmission fails, through the service query / response message of the service object group, the connectivity of the communication channel between the roadside device and the vehicle-mounted device is confirmed, and after the confirmation, the data is retransmitted, the breakpoint resume transmission of the data is realized, and the integrity of the file transmission is ensured.

[0231] The embodiment of the present application also provides a data service system, Figure 11 The composition structure schematic diagram of the data service system provided by the embodiment of the present application is shown as follows. Figure 11 As shown in the figure, the system comprises a roadside device 51 and a vehicle-mounted device 52, and the roadside device and the vehicle-mounted device are both deployed with at least two communication modules.

[0232] The roadside device 51 is used for sending a service notification message through a main communication channel, the service notification message comprises service information and channel information, and the service notification message is used for notifying the vehicle-mounted device 52 of at least one service provided and the backup communication channel information corresponding to each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel;

[0233] The vehicle-mounted device 52 is configured to receive the service announcement message sent by the roadside device 51 through the main communication channel, and further configured to determine a first service subscribed by the vehicle-mounted device 52 and first backup communication channel information corresponding to a first backup communication channel corresponding to the first service according to the service information and the channel information, and send a service response message to the roadside device 51, wherein the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, which indicates whether to subscribe to the service or not; and the first backup communication channel information is used for switching the vehicle-mounted device to the first backup communication channel to use the first service.

[0234] The roadside device 51 is further configured to receive the service response message sent by the vehicle-mounted device 52, and establish a first correspondence relationship between the first service and at least one vehicle-mounted device 52 based on the service response messages of the plurality of vehicle-mounted devices 52, wherein the first identifier in the service response message corresponding to the at least one vehicle-mounted device 52 indicates that the first service is subscribed, and the first service is any one of the at least one service, and the first backup communication channel information corresponding to the first service is used for switching the roadside device 51 to the first backup communication channel to provide the first service.

[0235] In an optional embodiment of the present application, the roadside device 51 is further configured to determine a main communication frequency based on a main frequency point corresponding to the main communication channel before sending the service announcement message through the main communication channel, and further configured to select a backup communication frequency corresponding to each service for the at least one service based on the main communication frequency and a preset frequency range, and determine a backup frequency point based on the backup communication frequency; and the backup communication channel information corresponding to each service comprises the backup frequency point determined based on the backup communication frequency selected for each service.

[0236] In an optional embodiment of the present application, the service information comprises at least one service identifier, service description information corresponding to each service, and backup communication channel identifier corresponding to each service; and / or, the channel information comprises the following information of the backup communication channel corresponding to each service: backup communication channel identifier, frequency point of the backup communication channel, and state information of the backup communication channel.

[0237] The vehicle-mounted device 52 is configured to determine a first service subscribed by the vehicle-mounted device 52 through the service information, find the service information according to the identifier of the first service, and determine a first backup communication channel identifier corresponding to the first service; configured to find the channel information according to the first backup communication channel identifier, and obtain first backup communication channel information corresponding to the first backup communication channel identifier, wherein the first backup communication channel information comprises a frequency point of the backup communication channel and state information of the backup communication channel; and further configured to switch to the first backup communication channel based on the first backup communication channel information.

[0238] In an optional embodiment of the present application, the vehicle-mounted device 52 is further configured to switch to the first backup communication channel based on the first backup communication channel information.

[0239] In an optional embodiment of the present application, the roadside device 51 is further configured to send a service query message through the first backup communication channel corresponding to the first service, and the service query message is used to confirm whether the vehicle-mounted device 52 subscribing to the first service switches to access the first backup communication channel.

[0240] The vehicle-mounted device 52 is further configured to receive the service query message sent by the roadside device 51 through the first backup communication channel, and the service query message is used to confirm whether the vehicle-mounted device 52 subscribing to the first service switches to access the first backup communication channel, and further configured to send a service reply message to the roadside device 51.

[0241] The roadside device 51 is further configured to determine whether the service reply message sent by the vehicle-mounted device 52 is received, and if the service reply message sent by the vehicle-mounted device 52 is received, it is determined that the vehicle-mounted device 52 switches to access the first backup communication channel, and if the service reply message sent by the vehicle-mounted device 52 is not received, it is determined that the vehicle-mounted device 52 does not switch to access the first backup communication channel.

[0242] In an optional embodiment of the present application, the service query message includes a device identification field used to identify at least one vehicle-mounted device corresponding to the first service, a service identification field used to identify the first service, and a service state field used to identify the service state.

[0243] When the values of the device identification fields in the service query message are all set to the first value, the service query message is used to confirm whether all vehicle-mounted devices 52 subscribing to the first service switch to access the first backup communication channel.

[0244] When the values of the device identification fields in the service query message are not all set to the first value, the service query message further includes the device identification of a specific vehicle-mounted device, and the service query message is used to confirm whether the specific vehicle-mounted device subscribing to the first service switches to access the first backup communication channel.

[0245] In an optional embodiment of the present application, the roadside device 51 is further configured to send a file service start message through the first backup communication channel corresponding to the first service after block processing of the to-be-transmitted data, and the file service start message includes the related information of the to-be-transmitted data, and the related information of the to-be-transmitted data includes the file name, the file block size, the file block quantity, and the file verification information.

[0246] The vehicle-mounted device 52 is further configured to receive a file service start message sent by the roadside device 51 through the first backup communication channel.

[0247] In an optional embodiment of the present application, the roadside device 51 is further configured to send a first file service transmission message through the first backup communication channel, wherein the first file service transmission message comprises a first file block identifier and a file block corresponding to the first file block identifier.

[0248] The vehicle-mounted device 52 is further configured to receive a first file service transmission message sent by the roadside device 51 through the first backup communication channel, and further configured to send a first file block response message to the roadside device 51, wherein the first file block response message comprises at least a received first file block identifier.

[0249] The roadside device 51 is further configured to receive a first file block response message sent by the vehicle-mounted device 52.

[0250] In an optional embodiment of the present application, the roadside device 51 is configured to start a timer after sending the first file service transmission message, and receive a first file block response message sent by the vehicle-mounted device 52 within a timing range of the timer.

[0251] In an optional embodiment of the present application, the roadside device 51 is further configured to resend a service query message through the first backup communication channel if no first file block response message sent by any vehicle-mounted device 52 subscribing to the first service is received within the timing range of the timer, wherein the service query message is used to confirm whether all vehicle-mounted devices 52 subscribing to the first service switch to access the first backup communication channel, and wherein data transmission is determined to fail if no service reply message sent by any vehicle-mounted device 52 is received.

[0252] In an optional embodiment of the present application, the roadside device 51 is further configured to resend a service query message through the first backup communication channel if no first file block response message sent by a first vehicle-mounted device subscribing to the first service is received within the timing range of the timer, wherein the service query message is used to confirm whether the first vehicle-mounted device switches to access the first backup communication channel, wherein the first vehicle-mounted device is any vehicle-mounted device among all vehicle-mounted devices subscribing to the first service, wherein it is determined that the first vehicle-mounted device has left the first corresponding relationship if no service reply message sent by the first vehicle-mounted device is received, and wherein the first file service transmission message is resent through the first backup communication channel if a service reply message sent by the first vehicle-mounted device is received.

[0253] In an optional embodiment of the present application, the roadside device 51 is further configured to continue sending the second file service transmission message through the first backup communication channel if the first file block acknowledgement message sent by all the vehicle-mounted devices 52 subscribing to the first service is received within the timing range of the timer, and the second file service transmission message includes a second file block identifier and a file block corresponding to the second file block identifier.

[0254] In an optional embodiment of the present application, the vehicle-mounted device 52 is further configured to perform a check according to the to-be-transmitted data and file check information after the transmission of the to-be-transmitted data is completed, and send a transmission completion notification message to the roadside device 51 after the check is passed.

[0255] The roadside device 51 is further configured to receive the transmission completion notification message sent by the vehicle-mounted device 52.

[0256] In an optional embodiment of the present application, the vehicle-mounted device 52 is further configured to switch back to the main communication channel from the first backup communication channel after the first service is completed if it is confirmed that there is no other service on the first backup communication channel.

[0257] In Figure 11 In the data service system shown in the figure, only two vehicle-mounted devices are shown, and in actual applications, the number of vehicle-mounted devices is not limited to two, and can be more, which is not limited in the embodiment.

[0258] Exemplarily, Figure 12 An optional flowchart of a C-V2X-based data service method provided by an embodiment of the present application is shown, as shown in Figure 12 The roadside device deploying the C-V2X module provides the vehicle-mounted device deploying the C-V2X module with a subscribable data service through the C-V2X main communication channel, and provides the vehicle-mounted device subscribing to the first service with a specific block transmission scheme of large file data through the first backup communication channel.

[0259] The roadside device establishes a connection with the server background providing service data through roadside device service identity authentication, and when the authentication result is correct, the roadside device downloads the relevant file data corresponding to the service, and can update each file data in time through the optical fiber network based on the update information of the background; the roadside device configures a backup frequency point of the C-V2X module for all the services provided, and each C-V2X module prepares to transmit the file data corresponding to each service to the vehicle-mounted device on the backup communication channel corresponding to the configured backup frequency point;

[0260] The roadside device sends a service announcement message to the vehicle-mounted device to announce the provided services and the standby communication channel information corresponding to the services on the main communication channel corresponding to the main frequency point; the vehicle-mounted device sends a service response message to the roadside device on the main communication channel corresponding to the main frequency point after receiving the service announcement message sent by the roadside device; the service response message at least includes the service identifier of the service subscribed by the vehicle-mounted device;

[0261] The roadside device establishes a service object group representing all vehicle-mounted devices subscribing to a certain service according to the received service response message for each service, and the service object group is equivalent to the first correspondence relationship in the above embodiment; for example, the service object group is represented as {service identifier: vehicle-mounted device 1, vehicle-mounted device 2, …, vehicle-mounted device n};

[0262] The vehicle-mounted device switches from the original main communication channel to the first standby communication channel corresponding to the first service based on the information carried in the service announcement message according to the first service subscribed by the vehicle-mounted device;

[0263] The roadside device sends a service query message (i.e., a general query) to all vehicle-mounted devices subscribing to the first service on the first standby communication channel according to the service object group corresponding to the first service, to confirm whether all vehicle-mounted devices subscribing to the first service have switched to the first standby communication channel; the roadside device receives a service response message returned by the vehicle-mounted device; wherein the roadside device determines whether the vehicle-mounted device has switched to the first standby communication channel according to whether the service response message returned by the vehicle-mounted device is received; if there is a vehicle-mounted device subscribing to the first service that does not return the service response message, it can be determined that the vehicle-mounted device subscribing to the first service has not all switched to the first standby communication channel, and further, the roadside device can send a service query message to the vehicle-mounted device that does not return the service response message through a specified query to determine whether the vehicle-mounted device has switched to the first standby communication channel, until it is determined that all vehicle-mounted devices subscribing to the first service have switched to the first standby communication channel, or the roadside device removes the vehicle-mounted device that has not returned the service response message through modifying the service object group (the first correspondence relationship);

[0264] After determining that all vehicle-mounted devices subscribing to the first service have switched to the first standby communication channel, the roadside device performs block processing on the file data downloaded from the server background, and sends a file service start message to the vehicle-mounted device on the first standby communication channel to inform the vehicle-mounted device of the related information of the file to be transmitted corresponding to the first service;

[0265] The roadside device sends a first file service transmission message corresponding to a first file block to the vehicle-mounted device on the first standby communication channel;

[0266] The vehicle-mounted device writes the first file block after receiving the first file service transmission packet, and sends a first file block response packet to the roadside device on the first backup communication channel;

[0267] The roadside device performs response verification on the vehicle-mounted device based on whether the first file block response packet is received, and performs retransmission processing on the vehicle-mounted device that fails the verification based on the service object group; wherein the roadside device re-sends a service query packet to the vehicle-mounted device that fails the verification, performs first file block retransmission processing after receiving the corresponding service response packet, and sends a second file service transmission packet corresponding to a second file block to the vehicle-mounted device that passes the verification, to realize breakpoint resume of file data;

[0268] After the roadside device verifies the responses of all vehicle-mounted devices based on the first file block response packet, it continues to transmit a second file service transmission packet corresponding to a second file block, and so on.

[0269] After the vehicle-mounted device receives all file blocks, it verifies the written file, and if the verification is passed, the file is legitimate, and after confirming that there is no other service on the first backup communication channel, it switches back to the main communication channel from the first backup communication channel, and continues to interact with the roadside device through the C-V2X scene calculation on the main communication channel to perform C-V2X message set interaction.

[0270] By applying multiple C-V2X communication channels to the roadside device and the vehicle-mounted device, a service-oriented collaborative working mechanism is established between the roadside device and the vehicle-mounted device deployed with the C-V2X module; by switching the vehicle-mounted device from the main communication channel to the backup communication channel corresponding to the service to accept the service, more occupation of the main communication channel is avoided, which reduces the working efficiency of the main communication channel; by deploying a large file data transmission protocol on multiple C-V2X communication channels, the roadside device has higher efficient integrity file transmission capability when transmitting large file data to the vehicle-mounted device.

[0271] The embodiment of the application also provides a data service device applied to a roadside device, Figure 13 The composition structure of the data service device provided by the embodiment of the application is shown in Figure 1 As shown in Figure 13 , the device comprises a first sending unit 61, a first receiving unit 62 and a first processing unit 63; wherein,

[0272] The first sending unit 61 is configured to send a service announcement packet through the main communication channel, wherein the service announcement packet comprises service information and channel information, and the service announcement packet is used to announce at least one service provided to the vehicle-mounted device and the backup communication channel information corresponding to each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel;

[0273] The first receiving unit 62 is configured to receive a service response message sent by the vehicle-mounted device, wherein the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, the first identifier indicating subscription or rejection of subscription of a service.

[0274] The first processing unit 63 is configured to establish a first correspondence relationship between a first service and at least one vehicle-mounted device based on the service response messages of the plurality of vehicle-mounted devices, the first identifier in the service response message corresponding to the at least one vehicle-mounted device indicating subscription of the first service, the first service being any one of the at least one service, and the first backup communication channel information corresponding to the first service being used by the road-side device to switch to the first backup communication channel to provide the first service.

[0275] In an optional embodiment of the present application, the first processing unit 63 is further configured to determine a main communication frequency based on a main frequency point corresponding to the main communication channel before the first sending unit 61 sends the service announcement message through the main communication channel; and further configured to select a backup communication frequency corresponding to each service based on the main communication frequency and a preset frequency range, and determine a backup frequency point based on the backup communication frequency; the backup frequency point determined based on the backup communication frequency corresponding to each service being included in the backup communication channel information corresponding to each service.

[0276] In an optional embodiment of the present application, the service information comprises at least one service identifier, service description information corresponding to each service, and communication channel identifier corresponding to each service; and / or, the channel information comprises the following information of the backup communication channel corresponding to each service: backup communication channel identifier, frequency point of the backup communication channel, and state information of the backup communication channel.

[0277] In an optional embodiment of the present application, the first sending unit 61 is further configured to send a service query message through the first backup communication channel corresponding to the first service, the service query message being used to confirm whether the vehicle-mounted device subscribing to the first service switches to access the first backup communication channel.

[0278] The first processing unit 63 is further configured to determine whether the first receiving unit 62 receives a service reply message sent by the vehicle-mounted device, and if the first receiving unit 62 receives the service reply message sent by the vehicle-mounted device, it is determined that the vehicle-mounted device switches to access the first backup communication channel, and if the first receiving unit 62 does not receive the service reply message sent by the vehicle-mounted device, it is determined that the vehicle-mounted device does not switch to access the first backup communication channel.

[0279] In an optional embodiment of the present application, the service query message comprises a device identification field for identifying at least one vehicle-mounted device corresponding to the first service, a service identification field for identifying the first service, and a service state field for identifying a service state.

[0280] In an optional embodiment of the present application, when the values of the device identification fields in the service query message are all set as a first value, the service query message is used to confirm whether all vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel; when the values of the device identification fields in the service query message are not all the first value, the service query message further comprises a device identification of a specific vehicle-mounted device, and the service query message is used to confirm whether the specific vehicle-mounted device subscribing to the first service switches to access the first backup communication channel.

[0281] In an optional embodiment of the present application, the first processing unit 63 is further configured to perform block processing on the to-be-transmitted data.

[0282] The first sending unit 61 is further configured to send a file service start message through the first backup communication channel corresponding to the first service, and the file service start message comprises related information of the to-be-transmitted data.

[0283] In an optional embodiment of the present application, the related information of the to-be-transmitted data at least comprises a file name, a file block size, a file block quantity, and file check information.

[0284] In an optional embodiment of the present application, the first sending unit 61 is further configured to send a first file service transmission message through the first backup communication channel, and the first file service transmission message comprises a first file block identification and a file block corresponding to the first file block identification.

[0285] The first receiving unit 62 is further configured to receive a first file block response message sent by the vehicle-mounted device, and the first file block response message at least comprises a received first file block identification.

[0286] In an optional embodiment of the present application, the first processing unit 63 is further configured to start a timer after the first sending unit 61 sends the first file service transmission message.

[0287] The first receiving unit 62 is configured to receive the first file block response message sent by the vehicle-mounted device within a timing range of the timer.

[0288] In an optional embodiment of the present application, the first sending unit 61 is further configured to resend the service query message through the first backup communication channel within the timing range of the timer if the first receiving unit 62 does not receive the first file block acknowledgement message sent by any vehicle-mounted device subscribing to the first service.

[0289] The first processing unit 63 is further configured to determine that the first vehicle-mounted device has left the first correspondence relationship when the first receiving unit 62 does not receive the service reply message sent by the first vehicle-mounted device.

[0290] In an optional embodiment of the present application, the first sending unit 61 is further configured to resend the service query message through the first backup communication channel within the timing range of the timer if the first receiving unit 62 does not receive the first file block acknowledgement message sent by the first vehicle-mounted device subscribing to the first service, and the service query message is used to confirm whether the first vehicle-mounted device switches to access the first backup communication channel, the first vehicle-mounted device being any vehicle-mounted device among all vehicle-mounted devices subscribing to the first service; and resend the first file service transmission message through the first backup communication channel when the first receiving unit 62 receives the service reply message sent by the first vehicle-mounted device.

[0291] The first processing unit 63 is further configured to determine that the first vehicle-mounted device has left the first correspondence relationship when the first receiving unit 62 does not receive the service reply message sent by the first vehicle-mounted device.

[0292] In an optional embodiment of the present application, the first sending unit 61 is further configured to continue to send the second file service transmission message through the first backup communication channel within the timing range of the timer if the first receiving unit 62 receives the first file block acknowledgement message sent by all vehicle-mounted devices subscribing to the first service, and the second file service transmission message includes the second file block identifier and the file block corresponding to the second file block identifier.

[0293] In an optional embodiment of the present application, the first receiving unit 62 is further configured to receive the transmission completion notification message sent by the vehicle-mounted device after the transmission of the to-be-transmitted data is completed.

[0294] In the embodiment of the present application, the first processing unit 63 in the device can be implemented by a central processing unit (CPU), a digital signal processor (DSP), a microcontroller unit (MCU) or a field-programmable gate array (FPGA) in actual application; and the first sending unit 61 and the first receiving unit 62 in the device can be implemented by a communication module (including a basic communication suite, an operating system, a communication module, a standardized interface and a protocol, etc.) and a transceiving antenna in actual application.

[0295] The embodiment of the present application further provides a data service device applied to a vehicle-mounted equipment, Figure 14 The composition structure of the data service device provided by the embodiment of the present application is shown in Figure 2 Figure 14 As shown in the figure, the device comprises a second receiving unit 71, a second processing unit 72 and a second sending unit 73; wherein,

[0296] The second receiving unit 71 is configured to receive a service announcement message sent by a roadside equipment through a main communication channel, the service announcement message comprising service information and channel information, the service announcement message being configured to announce at least one service provided by the roadside equipment and the corresponding backup communication channel information of each service to the vehicle-mounted equipment; the frequency point of the backup communication channel corresponding to the backup communication channel information being different from the frequency point of the main communication channel;

[0297] The second processing unit 72 is configured to determine a first service subscribed by the vehicle-mounted equipment and the first backup communication channel information corresponding to the first backup communication channel corresponding to the first service according to the service information and the channel information;

[0298] The second sending unit 73 is configured to send a service response message to the roadside equipment, the service response message comprising at least one service identifier and a first identifier corresponding to each service identifier, the first identifier being configured to represent a service subscribed or a service refused, and the first backup communication channel information being configured to enable the vehicle-mounted equipment to switch to the backup communication channel to use the first service.

[0299] In an optional embodiment of the present application, the service information comprises at least one service identifier, service description information corresponding to each service and backup communication channel identifier corresponding to each service; and / or the channel information comprises the following information of the backup communication channel corresponding to each service: backup communication channel identifier, frequency point of the backup communication channel and state information of the backup communication channel.

[0300] ​In an optional embodiment of the present application, the second processing unit 72 is configured to determine the first service subscribed by the vehicle-mounted device through the service information, find the service information according to the identification of the first service, and determine the first communication channel identification corresponding to the first service; and is further configured to find the channel information according to the first communication channel identification, obtain the first backup communication channel information corresponding to the first communication channel identification, and the first backup communication channel information includes the frequency point of the backup communication channel and the state information of the backup communication channel.

[0301] In an optional embodiment of the present application, the second processing unit 72 is further configured to switch to the first backup communication channel based on the first communication channel information.

[0302] In an optional embodiment of the present application, the second receiving unit 71 is further configured to receive the service query message sent by the roadside device through the first backup communication channel, and the service query message is used to confirm whether the vehicle-mounted device subscribed to the first service switches to access the first backup communication channel.

[0303] The second sending unit 73 is further configured to send the service reply message to the roadside device.

[0304] In an optional embodiment of the present application, the service query message includes a device identification field used to identify at least one vehicle-mounted device corresponding to the first service, a service identification field used to identify the first service, and a service state field used to identify the service state.

[0305] In an optional embodiment of the present application, when the values of the device identification fields in the service query message are all set as the first value, the service query message is used to confirm whether all vehicle-mounted devices subscribed to the first service switch to access the first backup communication channel.

[0306] When the values of the device identification fields in the service query message are not all set as the first value, the service query message further includes the device identification of a specific vehicle-mounted device, and the service query message is used to confirm whether the specific vehicle-mounted device subscribed to the first service switches to access the first backup communication channel.

[0307] In an optional embodiment of the present application, the second receiving unit 71 is further configured to receive the file service start message sent by the roadside device through the first backup communication channel, and the file service start message includes the related information of the to-be-transmitted data.

[0308] In an optional embodiment of the present application, the related information of the to-be-transmitted data at least includes the file name, the file block size, the file block quantity, and the file check information.

[0309] In an optional embodiment of the present application, the second receiving unit 71 is further configured to receive a first file service transmission packet sent by the roadside device through the first backup communication channel, and the first file service transmission packet comprises a first file block identifier and a file block corresponding to the first file block identifier.

[0310] The second sending unit 73 is further configured to send a first file block response packet to the roadside device, and the first file block response packet comprises at least the received first file block identifier.

[0311] In an optional embodiment of the present application, the second processing unit 72 is further configured to perform a check according to the to-be-transmitted data and the file check information after the transmission of the to-be-transmitted data is completed.

[0312] The second sending unit 73 is further configured to send a transmission completion notification packet to the roadside device after the check is passed.

[0313] In an optional embodiment of the present application, the second processing unit 72 is further configured to switch back to the main communication channel from the first backup communication channel after the first service is completed and it is confirmed that there is no other service in the first backup communication channel.

[0314] In the embodiment of the present application, the second processing unit 72 in the device can be implemented by a CPU, a DSP, an MCU or an FPGA in actual application; and the second receiving unit 71 and the second sending unit 73 in the device can be implemented by a communication module (including a basic communication suite, an operating system, a communication module, a standardized interface and a protocol, etc.) and a transceiving antenna in actual application.

[0315] It should be noted that the data service device described above provides data services, and the above-mentioned division of program modules is only used as an example for illustration, and in actual application, the above-mentioned processing can be completed by different program modules according to needs, that is, the internal structure of the device is divided into different program modules to complete all or part of the processing described above. In addition, the data service device and the data service method provided in the above-mentioned embodiments belong to the same concept, and the specific implementation process is described in detail in the method embodiments, which will not be described here.

[0316] The embodiment of the present application further provides a communication device, Figure 15 The hardware composition structure diagram of the communication device provided in the embodiment of the present application is shown in Figure 15 The communication device comprises a memory 82, a processor 81, and a computer program stored in the memory 82 and capable of running on the processor 81.

[0317] Optionally, the communication device can be a roadside device or a vehicle-mounted device of the embodiment of the application; the processor 81 implements the steps of the data service method applied to the roadside device or the vehicle-mounted device of the embodiment of the application when executing the program.

[0318] Optionally, the communication device further comprises at least one communication component 84. In the communication device, various components can be coupled together through a bus system 83. It can be understood that the bus system 83 is used to realize the connection communication between the components. In addition to the data bus, the bus system 83 also includes a power bus, a control bus and a status signal bus. However, in order to clearly illustrate, all kinds of buses are marked as the bus system 83 in the Figure 15

[0319] ​It can be appreciated that the memory 82 can be a volatile memory or a non-volatile memory, and can also include both volatile and non-volatile memory. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a ferromagnetic random access memory (FRAM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM). The magnetic surface memory can be a disk memory or a tape memory. The volatile memory can be a random access memory (RAM) used as an external cache. By way of example but not limitation, many forms of RAM can be used, such as static random access memory (SRAM), synchronous static random access memory (SSRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), sync link dynamic random access memory (SLDRAM), and direct rambus random access memory (DRRAM).The memory 82 described in the embodiments of the present application is intended to include, but not limited to, these and any other suitable type of memory.

[0320] The method disclosed in the embodiments of the present application can be applied in the processor 81 or implemented by the processor 81. The processor 81 can be an integrated circuit chip having a processing capability of signals. In the implementation process, each step of the above method can be completed by the integrated logic circuit of hardware in the processor 81 or the instruction in the form of software. The processor 81 described above can be a general processor, a DSP, or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc. The processor 81 can implement or execute the disclosed methods, steps and logic block diagrams in the embodiments of the present application. The general processor can be a microprocessor or any conventional processor, etc. In combination with the steps of the method disclosed in the embodiments of the present application, the hardware decoding processor can be directly embodied to complete the execution, or the combination of hardware and software modules in the decoding processor can be used to complete the execution. The software module can be located in the storage medium, which is located in the memory 82. The processor 81 reads the information in the memory 82 and combines the hardware to complete the steps of the above method.

[0321] In the exemplary embodiments, the communication device can be implemented by one or more ASICs (Application Specific Integrated Circuits), DSPs, PLDs (Programmable Logic Devices), CPLDs (Complex Programmable Logic Devices), FPGAs, general-purpose processors, controllers, MCUs, microprocessors (Microprocessors), or other electronic elements, for executing the above method.

[0322] The embodiments of the present application also provide a computer readable storage medium, which has a computer program stored thereon.

[0323] Optionally, the computer readable storage medium can be applied to the enterprise operating condition early warning device of the embodiments of the present application; and the program is executed by the processor to implement the steps of the data service method applied to the roadside equipment or the vehicle-mounted equipment of the embodiments of the present application.

[0324] The methods disclosed in the several method embodiments provided in the present application can be combined arbitrarily without conflict, to obtain new method embodiments.

[0325] The features disclosed in the several product embodiments provided in the present application can be combined arbitrarily without conflict, to obtain new product embodiments.

[0326] The features disclosed in the several method or device embodiments provided by the present application can be combined arbitrarily without conflict to obtain new method embodiments or device embodiments.

[0327] In the several embodiments provided by the present application, it should be understood that the disclosed device and method can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There can be another division during actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed coupling, or direct coupling or communication connection between the components can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or in other forms.

[0328] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or distributed on a plurality of network units; some or all of the units can be selected according to actual needs to achieve the purpose of the present embodiment.

[0329] In addition, each functional unit in each embodiment of the present application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be realized in the form of hardware, or in the form of hardware plus software functional unit.

[0330] Those of ordinary skill in the art can understand that all or part of the steps of the above method embodiments can be completed by program instructions related to hardware, and the foregoing program can be stored in a computer readable storage medium, and when the program is executed, the steps of the method embodiments are executed; and the foregoing storage medium includes mobile storage devices, ROM, RAM, magnetic disks or optical disks and various media that can store program codes.

[0331] Alternatively, the above-mentioned integrated unit of the present application, if realized in the form of a software function module and sold or used as an independent product, can also be stored in a computer-readable storage medium. Based on such an understanding, the technical solutions of the embodiments of the present application can be embodied in the form of a software product in essence or in the form of a part of the prior art that contributes to the present application. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the method described in the embodiments of the present application. The aforementioned storage medium includes mobile storage devices, ROM, RAM, magnetic discs or optical discs, and various media that can store program codes.

[0332] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A data service method characterized by, The method is applied to a roadside device which deploys at least two communication modules, and the method comprises: The roadside device sends a service announcement message through a main communication channel, wherein the service announcement message comprises service information and channel information, and the service announcement message is used to announce at least one service provided by the roadside device and the corresponding backup communication channel information of each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from that of the main communication channel; The roadside device receives a service response message sent by the vehicle-mounted device, wherein the service response message comprises at least one service identifier and a first identifier corresponding to each service identifier, which indicates whether to subscribe to the service; The roadside device establishes a first corresponding relationship between a first service and at least one vehicle-mounted device based on the service response messages of multiple vehicle-mounted devices, wherein the first identifier in the service response message corresponding to the at least one vehicle-mounted device indicates that the first service is subscribed, and the first service is any one of the at least one service, and the first backup communication channel information corresponding to the first service is used for the roadside device to switch to the first backup communication channel to provide the first service; The method further comprises: the roadside device sends a service query message through the first backup communication channel corresponding to the first service, and the service query message is used to confirm whether the vehicle-mounted device subscribing to the first service switches to access the first backup communication channel; The roadside device determines whether to receive a service reply message sent by the vehicle-mounted device, and if the service reply message sent by the vehicle-mounted device is received, it is determined that the vehicle-mounted device switches to access the first backup communication channel, and if the service reply message sent by the vehicle-mounted device is not received, it is determined that the vehicle-mounted device does not switch to access the first backup communication channel.

2. The method of claim 1, wherein, Before the roadside device sends the service announcement message through the main communication channel, the method further comprises: The roadside device determines a main communication frequency based on a main frequency point corresponding to the main communication channel; The roadside device selects a backup communication frequency corresponding to each service for the at least one service based on the main communication frequency and a preset frequency range, and determines a backup frequency point based on the backup communication frequency; The backup communication channel information corresponding to each service comprises the backup frequency point determined based on the backup communication frequency selected for each service.

3. The method of claim 1, wherein, The service query message comprises a device identifier field used to identify at least one vehicle-mounted device corresponding to the first service, a service identifier field used to identify the first service, and a service state field used to identify the service state; When the values of the device identifier fields in the service query message are all set to a first value, the service query message is used to confirm whether all vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel; When the values of the device identifier fields in the service query message are not all set to the first value, the service query message further comprises a device identifier of a specific vehicle-mounted device, and the service query message is used to confirm whether the specific vehicle-mounted device subscribing to the first service switches to access the first backup communication channel.

4. The method according to any one of claims 1 to 3, characterized in that, The method further comprises: The roadside device sends a file service start message through the first backup communication channel after block processing of the to-be-transmitted data, and the file service start message includes related information of the to-be-transmitted data, and the related information of the to-be-transmitted data includes a file name, a file block size, a file block quantity and file check information.

5. The method of claim 4, wherein, The method further includes: The roadside device sends a first file service transmission message through the first backup communication channel, and the first file service transmission message includes a first file block identifier and a file block corresponding to the first file block identifier; The roadside device receives a first file block response message sent by the vehicle-mounted device, and the first file block response message at least includes a received first file block identifier.

6. The method of claim 5, wherein, The roadside device receives a first file block response message sent by the vehicle-mounted device, including: After sending the first file service transmission message, the roadside device starts a timer, and receives the first file block response message sent by the vehicle-mounted device within a timing range of the timer.

7. The method of claim 6, wherein, The method further includes: If the roadside device does not receive the first file block response message sent by any vehicle-mounted device subscribing to the first service within the timing range of the timer, the service query message is sent again through the first backup communication channel, and the service query message is used to confirm whether all vehicle-mounted devices subscribing to the first service switch to access the first backup communication channel; When the roadside device does not receive the service reply message sent by any vehicle-mounted device, it is confirmed that the data transmission fails.

8. The method of claim 6, wherein, The method further includes: If the roadside device does not receive the first file block response message sent by the first vehicle-mounted device subscribing to the first service within the timing range of the timer, the service query message is sent again through the first backup communication channel, and the service query message is used to confirm whether the first vehicle-mounted device switches to access the first backup communication channel; the first vehicle-mounted device is any vehicle-mounted device among all vehicle-mounted devices subscribing to the first service; If the roadside device does not receive the service reply message sent by the first vehicle-mounted device, it is determined that the first vehicle-mounted device has left the first corresponding relationship; If the roadside device receives the service reply message sent by the first vehicle-mounted device, the first file service transmission message is sent again through the first backup communication channel.

9. The method of claim 6, wherein, The method further includes: If the roadside device receives the first file block response message sent by all vehicle-mounted devices subscribing to the first service within the timing range of the timer, the second file service transmission message is continued to be sent through the first backup communication channel, and the second file service transmission message includes a second file block identifier and a file block corresponding to the second file block identifier.

10. The method according to any one of claims 5 to 9, characterized in that, The method further includes: After the to-be-transmitted data transmission is completed, the roadside device receives a transmission completion notification message sent by the vehicle-mounted device.

11. A data service method characterized by, The method is applied to a vehicle-mounted device, the vehicle-mounted device deploys at least two communication modules, and the method includes: The vehicle-mounted device receives a service announcement message sent by the roadside device through a main communication channel, the service announcement message including service information and channel information, the service announcement message being used to announce at least one service provided to the vehicle-mounted device and the corresponding backup communication channel information of each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel; The vehicle-mounted device determines a first service subscribed and first backup communication channel information corresponding to the first backup communication channel of the first service through the service information and the channel information, and sends a service response message to the roadside device, the service response message including at least one service identifier and a first identifier corresponding to each service identifier indicating subscription service or rejection of subscription service, the first backup communication channel information being used for the vehicle-mounted device to switch to the first backup communication channel to use the first service; The method further includes: the vehicle-mounted device receiving a service query message sent by the roadside device through the first backup communication channel, the service query message being used to confirm whether the vehicle-mounted device subscribed to the first service switches to access the first backup communication channel; The vehicle-mounted device sends a service reply message to the roadside device.

12. The method of claim 11, wherein, The service information includes: at least one service identifier, service description information corresponding to each service, and backup communication channel identifier corresponding to each service; and / or The channel information includes the following information of the backup communication channel corresponding to each service: backup communication channel identifier, frequency point of the backup communication channel, and state information of the backup communication channel; The vehicle-mounted device determines a first service subscribed and first backup communication channel information corresponding to the first backup communication channel of the first service through the service information and the channel information, including: The vehicle-mounted device determines a first service subscribed through the service information, finds the service information according to the identifier of the first service, and determines a first backup communication channel identifier corresponding to the first service; According to the first backup communication channel identifier, the channel information is found to obtain first backup communication channel information corresponding to the first backup communication channel identifier, the first backup communication channel information including the frequency point of the backup communication channel and the state information of the backup communication channel.

13. The method of claim 11, wherein, The method further includes: The vehicle-mounted device switches to the first backup communication channel based on the first backup communication channel information.

14. The method of claim 13, wherein, The method further includes: The vehicle-mounted device receives a file service start message sent by the roadside device through the first backup communication channel, wherein the file service start message includes related information of to-be-transmitted data, and the related information of the to-be-transmitted data includes: file name, file block size, file block quantity, and file verification information.

15. The method of claim 14, wherein, The method further includes: The vehicle-mounted device receives a first file service transmission message sent by the roadside device through the first backup communication channel, the first file service transmission message including a first file block identifier and a file block corresponding to the first file block identifier; The vehicle-mounted device sends a first file block response message to the roadside device, and the first file block response message at least includes the received first file block identifier.

16. The method of claim 15, wherein, The method further includes: After the vehicle-mounted device completes the transmission of the to-be-transmitted data, the vehicle-mounted device performs a check according to the to-be-transmitted data and the file check information, and sends a transmission completion notification message to the roadside device after the check is passed.

17. The method of claim 16, wherein, The method further includes: After the vehicle-mounted device ends the first service, if it is confirmed that the first backup communication channel has no other service, the vehicle-mounted device switches back to the main communication channel from the first backup communication channel.

18. A data service system characterized by The system includes a roadside device and a vehicle-mounted device, and both the roadside device and the vehicle-mounted device are provided with at least two communication modules; wherein, The roadside device is configured to send a service notification message through a main communication channel, the service notification message including service information and channel information, and the service notification message is used to notify the vehicle-mounted device of at least one service provided and backup communication channel information corresponding to each service; the frequency point of the backup communication channel corresponding to the backup communication channel information is different from the frequency point of the main communication channel; The vehicle-mounted device is configured to receive the service notification message sent by the roadside device through the main communication channel; further configured to determine a first service subscribed and first backup communication channel information corresponding to a first backup communication channel corresponding to the first service through the service information and the channel information, send a service response message to the roadside device, the service response message including at least one service identifier and a first identifier corresponding to each service identifier indicating subscription service or refusal to subscribe to the service; and the first backup communication channel information is used for the vehicle-mounted device to switch to the first backup communication channel to use the first service; The roadside device is further configured to receive the service response message sent by the vehicle-mounted device; based on the service response messages of multiple vehicle-mounted devices, establish a first correspondence relationship between the first service and at least one vehicle-mounted device, the first identifier in the service response message corresponding to the at least one vehicle-mounted device indicating subscription to the first service, and the first service being any one of the at least one service, wherein the first backup communication channel information corresponding to the first service is used for the roadside device to switch to the first backup communication channel to provide the first service; The roadside device is further configured to send a service query message through the first backup communication channel corresponding to the first service, and the service query message is used to confirm whether the vehicle-mounted device subscribing to the first service switches to access the first backup communication channel; The vehicle-mounted device is further configured to receive the service query message sent by the roadside device through the first backup communication channel, and the service query message is used to confirm whether the vehicle-mounted device subscribing to the first service switches to access the first backup communication channel; and further configured to send a service reply message to the roadside device. The roadside device is further configured to determine whether a service reply message sent by the vehicle-mounted device is received, determine that the vehicle-mounted device switches to access the first backup communication channel if the service reply message sent by the vehicle-mounted device is received, and determine that the vehicle-mounted device does not switch to access the first backup communication channel if the service reply message sent by the vehicle-mounted device is not received.

19. A communication device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein, The processor, when executing the program, implements the steps of the method in any one of claims 1 to 10, or The processor, when executing the program, implements the steps of the method in any one of claims 11 to 17.

20. A computer readable storage medium having stored thereon a computer program, characterized in that, The program, when executed by the processor, implements the steps of the method in any one of claims 1 to 10, or The program, when executed by the processor, implements the steps of the method in any one of claims 11 to 17.

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