Time synchronization method, device, equipment, vehicle and medium based on Internet of Vehicles

Abstract

The embodiments of the present application provide a time synchronization method, device, equipment, vehicle and medium based on the Internet of Vehicles, which relates to the field of Internet of Vehicles technology. The method is applied to a target vehicle in a vehicle cluster, which includes multiple vehicles. The method includes: after building a vehicle cluster and determining the target vehicle in the vehicle cluster, sending time request information to other vehicles in the vehicle cluster, and receiving local timestamps fed back by other vehicles; determining a time deviation value based on the current timestamp of the target vehicle and the local timestamps of each other vehicle; if it is determined that the time deviation value is greater than a preset deviation threshold, obtaining a global time error, and performing time synchronization processing on each vehicle in the vehicle cluster based on the global time error. The method is used to improve the scenario applicability of time synchronization, effectively reduce potential misjudgments and delayed responses due to time asynchrony, and improve the overall traffic management level and user experience.

Description

Technical Field

[0001] The present application relates to the field of vehicle networking technology, and specifically to a time synchronization method, device, equipment, vehicle and medium based on the vehicle networking. Background Art

[0002] With the rapid development of intelligent driving technology, the requirements for time synchronization are becoming increasingly higher in scenarios such as autonomous driving, intelligent traffic management, and high-security fleet collaboration.

[0003] In existing technologies, time synchronization based on vehicle-to-everything (V2X) technology mainly relies on road side units (RSUs) or fixed-level network elements, which provide precise time references to achieve time synchronization between vehicles.

[0004] However, these methods have limitations in dynamic networking environments. Due to vehicle mobility and frequent changes in network topology, fixed time synchronization infrastructure struggles to adapt to these dynamic environments, limiting its applicability. Furthermore, existing technologies lack effective privacy protection mechanisms during time synchronization, posing a significant risk of privacy breaches. Summary of the Invention

[0005] In order to solve the problems of limited applicable scenarios and large privacy leakage risks in existing time synchronization technologies, the embodiments of the present application provide a time synchronization method, device, equipment, vehicle and medium based on the Internet of Vehicles.

[0006] In a first aspect, an embodiment of the present application provides a time synchronization method based on an Internet of Vehicles. The method is applied to a target vehicle in a vehicle cluster, where the vehicle cluster includes multiple vehicles. The method includes:

[0007] After building a vehicle cluster and determining a target vehicle in the vehicle cluster, sending a time request message to other vehicles in the vehicle cluster and receiving local timestamps fed back by the other vehicles;

[0008] Determining a time offset value based on the current timestamp of the target vehicle and the local timestamps of each of the other vehicles; wherein the time offset value is used to indicate the time offset between the vehicles in the vehicle cluster;

[0009] If it is determined that the time deviation value is greater than a preset deviation threshold, a global time error is obtained, and time synchronization processing is performed on each vehicle in the vehicle cluster based on the global time error; wherein the global time error is used to indicate the time deviation between all vehicles in each vehicle cluster.

[0010] In a possible implementation, determining the time offset value based on the current timestamp of the target vehicle and the local timestamps of each of the other vehicles includes:

[0011] According to the current timestamp of the target vehicle and the local timestamps of each of the other vehicles, a preset Kalman filter formula is used to calculate an average time deviation value between the vehicles in the vehicle cluster, and determine it as the time deviation value.

[0012] In a possible implementation, obtaining the global time error includes:

[0013] exchanging respective time deviation values ​​with other target vehicles through multi-hop communication; the other target vehicles are target vehicles in other vehicle clusters whose time deviation values ​​are greater than a preset deviation threshold;

[0014] A global time error is determined based on the time deviation values.

[0015] In a possible implementation, determining the global time error according to each of the time deviation values ​​includes:

[0016] According to a preset global time reference, each of the time deviation values ​​is processed using a preset weighted sum algorithm to obtain a global time error.

[0017] In a possible implementation, performing time synchronization processing on each vehicle in the vehicle cluster according to the global time error includes:

[0018] Sending synchronization instruction information to other vehicles in the vehicle cluster; wherein the synchronization instruction information includes the global time error, and the synchronization instruction information is used to instruct the other vehicles to adjust local clocks according to the global time error.

[0019] In one possible implementation, before exchanging respective time offset values ​​with other target vehicles through multi-hop communication, the method further includes:

[0020] A zero-knowledge proof verification is performed between the target vehicle and the other target vehicles. If the verification is successful, a step of exchanging respective time offset values ​​with the other target vehicles through multi-hop communication is executed.

[0021] In a possible implementation, before sending the time request information to other vehicles in the vehicle cluster, the method further includes:

[0022] Check whether the GPS signal of the vehicle is available;

[0023] If not available, a vehicle cluster is constructed and the target vehicle in the vehicle cluster is determined.

[0024] In a possible implementation, the building of a vehicle cluster includes:

[0025] Receiving local timestamps broadcast by vehicles within a preset communication range and determining the total number of vehicles within the preset communication range; the local timestamps including geographic location information;

[0026] If it is determined that the total number of vehicles meets the preset numerical requirement, dividing the vehicles according to the geographical location information to obtain at least one vehicle cluster;

[0027] If it is determined that the total number of vehicles does not meet the preset numerical requirement, the preset communication range is expanded until the total number of vehicles meets the preset numerical requirement.

[0028] In a possible implementation, determining the target vehicle in the vehicle cluster includes:

[0029] Obtaining a node reputation value of each vehicle in the vehicle cluster; the node reputation value is used to indicate the timing stability of the vehicle;

[0030] Based on the Raft protocol, the vehicle with the largest node reputation value is selected as the target vehicle in the vehicle cluster.

[0031] In a possible implementation, obtaining the node reputation value of each vehicle in the vehicle cluster includes:

[0032] For each vehicle in the vehicle cluster, obtaining a clock error and a communication success rate of the vehicle within a target time period;

[0033] A weighted summation process is performed on the clock error and the communication success rate to obtain the node reputation value.

[0034] In one possible implementation, vehicles in the vehicle cluster are identified using temporary names, and the temporary names are regularly updated via blockchain; and / or differential privacy noise is injected into the local timestamp.

[0035] In a second aspect, an embodiment of the present application provides a time synchronization device based on an Internet of Vehicles, the device being applied to a target vehicle in a vehicle cluster, the vehicle cluster including multiple vehicles, the device comprising:

[0036] A transceiver unit is configured to, after building a vehicle cluster and determining a target vehicle in the vehicle cluster, send time request information to other vehicles in the vehicle cluster and receive local timestamps fed back by the other vehicles;

[0037] a calculation unit, configured to determine a time offset value based on a current timestamp of the target vehicle and a local timestamp of each of the other vehicles; wherein the time offset value is used to indicate a time offset between the vehicles in the vehicle cluster;

[0038] A processing unit is configured to obtain a global time error if it is determined that the time deviation value is greater than a preset deviation threshold, and to perform time synchronization processing on each vehicle in the vehicle cluster based on the global time error; wherein the global time error is used to indicate the time deviation between all vehicles in each vehicle cluster.

[0039] In a third aspect, an embodiment of the present application provides an electronic device, comprising: a memory, a processor;

[0040] The memory stores computer-executable instructions;

[0041] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementations of the first aspect.

[0042] In a fourth aspect, an embodiment of the present application provides a vehicle comprising the electronic device as described in the third aspect above.

[0043] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect above and / or various possible implementation methods of the first aspect.

[0044] In a sixth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the first aspect and / or various possible implementation methods of the first aspect.

[0045] The embodiments of the present application provide a method, apparatus, device, vehicle, and medium for time synchronization based on the Internet of Vehicles. By exchanging and synchronizing time information between a target vehicle and other vehicles in a vehicle cluster, the method quantifies the degree of time asynchrony between vehicles and performs effective time synchronization processing based on the exchange and synchronization of time information. This method can not only efficiently achieve time synchronization for all vehicles in any scenario, but also enhance the stability and security of the system. In particular, in autonomous driving and intelligent transportation systems, it can effectively reduce potential misjudgments and delayed responses caused by time asynchrony, thereby improving the overall traffic management level and user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0047] Figure 1 A system architecture diagram of time synchronization based on the Internet of Vehicles provided in an embodiment of the present application;

[0048] Figure 2 A flowchart of a time synchronization method based on an Internet of Vehicles provided in an embodiment of the present application;

[0049] Figure 3 A flowchart of another time synchronization method based on the Internet of Vehicles provided in an embodiment of the present application;

[0050] Figure 4 A schematic diagram of the structure of a time synchronization device based on the Internet of Vehicles provided in an embodiment of the present application;

[0051] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0052] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0053] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0054] Scenarios such as autonomous driving, intelligent traffic management, and high-security fleet collaboration often place high demands on time synchronization. When the signal from a standard time source, such as the Global Positioning System (GPS), is normal, time synchronization can be achieved based on that source. However, in complex road sections like tunnels and canyons, or in inclement weather like ice, snow, or strong winds, the signal from that source may be lost, making inter-vehicle time synchronization difficult.

[0055] In one example, time synchronization is achieved using centralized timing source technology. This involves comparing multiple timing sources before selecting a target source. Time synchronization relies on roadside units (RSUs) or fixed-level network elements. This solution requires a pre-defined centralized node, is unsuitable for dynamic vehicle networking scenarios, and presents a single point of failure risk.

[0056] Another example uses master-slave node synchronization technology to achieve time synchronization, primarily by having the master node send synchronization messages to calibrate the slave node time. This solution also fails to address the issue of dynamic vehicle networking and cannot be applied in scenarios involving fast-moving vehicles.

[0057] The aforementioned solutions all have significant limitations in dynamic networking environments, struggling to adapt to fast-moving vehicles and dynamically changing environments, and face limited applicability. Furthermore, during the time synchronization process, these solutions lack effective privacy protection mechanisms and anti-attack fault tolerance mechanisms, as well as effective defenses against malicious nodes (such as those sending false time information), posing a significant risk of privacy leaks.

[0058] To address the above technical issues, the present invention provides a method for time synchronization based on the Internet of Vehicles. This method, which builds a vehicle cluster based on dynamic vehicle networking to perform time synchronization, obtains the local timestamp of each vehicle in the cluster and determines the time deviation value based on the obtained local timestamp before performing time synchronization. This method not only achieves high-precision timing in dynamic scenarios without GPS signals, but also avoids centralization issues. Furthermore, the present invention also protects vehicle privacy and improves vehicle information security through multi-hop communication, differential privacy noise injection, the use of temporary names, and zero-knowledge proof verification.

[0059] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0060] Figure 1 This is a system architecture diagram of time synchronization based on the Internet of Vehicles provided in an embodiment of the present application. Figure 1 As shown in Figure 2, in the time synchronization based on the Internet of Vehicles, multiple vehicle clusters can be constructed, such as Figure 1 In vehicle clusters 1-3, each cluster includes multiple vehicles, one of which is the target vehicle and serves as the leader node for the cluster. Not only do the clusters exchange information via multi-hop communication links, but the vehicles in each cluster can also interact with the blockchain node to periodically update their temporary names. The global synchronization module synchronizes time based on the time data fed back by each vehicle in each cluster, achieving time synchronization.

[0061] It should be noted that Figure 1The global synchronization module can be a module deployed on the target vehicle in the vehicle cluster, or it can be deployed on an external server. In addition, each vehicle in the vehicle cluster may perform different functions in different vehicle clusters, which is not limited in this embodiment of the present application. This embodiment of the present application takes the global synchronization module deployed on the target vehicle in the vehicle cluster as an example for detailed description.

[0062] For example, Figure 2 The flowchart of a time synchronization method based on the Internet of Vehicles provided in an embodiment of the present application is shown in FIG. The time synchronization method based on the Internet of Vehicles provided in an embodiment of the present application is applied to a target vehicle in a vehicle cluster, which includes multiple vehicles. Figure 2 As shown, the time synchronization method based on the Internet of Vehicles provided in the embodiment of the present application may include:

[0063] S201: After building a vehicle cluster and determining a target vehicle in the vehicle cluster, send time request information to other vehicles in the vehicle cluster and receive local timestamps fed back by other vehicles.

[0064] For example, in an embodiment of the present application, a target vehicle in a vehicle cluster serves as the subgroup leader of the cluster and performs a time synchronization process. During time synchronization, the target vehicle needs to know the current time of other vehicles in the cluster in order to assess time differences. Therefore, the target vehicle can first send a time request message to other vehicles in the cluster. This time request message instructs the other vehicles to return their current local time. Upon receiving the request, the other vehicles in the cluster return their local timestamps to the target vehicle, which then receives the local timestamps returned by the other vehicles. The local timestamps are typically the internal clock times of these vehicles.

[0065] It should be noted that a vehicle cluster can be pre-established for any situation requiring time synchronization. When a target vehicle determines that time synchronization is required, a vehicle cluster is established according to a pre-configured dynamic networking process. The time synchronization process of this application can only be executed after the vehicle cluster is established and the target vehicle in the cluster is determined. Therefore, in one possible embodiment, when a vehicle cluster has not been pre-established, the target vehicle must first perform the following steps before sending a time request message to other vehicles in the vehicle cluster:

[0066] S01, detecting whether the GPS signal of the vehicle is available;

[0067] S02. If unavailable, construct a vehicle cluster and determine the target vehicle in the vehicle cluster.

[0068] For example, most vehicles currently have global positioning systems (GPS) installed, using them as a standard time source. If the GPS signals on each vehicle are available, each vehicle can calibrate its own time using the GPS, thereby achieving time synchronization. However, when the GPS signal is unavailable, each vehicle cannot calibrate its time using the same standard time source, and must instead use other methods, such as the solution in the embodiments of the present application, to achieve time synchronization. Therefore, the target vehicle needs to detect in real time whether its own GPS signal is available. If not, a vehicle cluster is constructed, and the target vehicle within the cluster is identified.

[0069] Optionally, in a possible embodiment, building a vehicle cluster may include:

[0070] S021. Receive local timestamps broadcast by vehicles within a preset communication range, and determine the total number of vehicles within the preset communication range; the local timestamps include geographic location information;

[0071] S022. If it is determined that the total number of vehicles meets the preset numerical requirement, then divide the number of vehicles according to the geographical location information to obtain at least one vehicle cluster;

[0072] S023. If it is determined that the total number of vehicles does not meet the preset numerical requirement, expand the preset communication range until the total number of vehicles meets the preset numerical requirement.

[0073] For example, when a vehicle detects that its GPS signal is unavailable, it typically broadcasts its clock status via V2V communication. This clock status typically includes its local timestamp. A target vehicle then receives the local timestamps broadcast by vehicles within a predetermined communication range, thereby determining the total number of vehicles within the predetermined communication range. The predetermined communication range is typically a range within which V2V communication is possible, such as 800 meters, though this embodiment of the present application does not impose any limitation thereto.

[0074] When the total number of vehicles within a preset communication range meets a preset numerical requirement (i.e., reaches or exceeds a specific threshold), the vehicles can be divided based on their geographic location information. For example, a group of geographically close vehicles can be identified as a vehicle cluster. When the total number of vehicles within the preset communication range is large, the cluster can be divided into multiple vehicle clusters. When the total number of vehicles within the preset communication range is small, the cluster can be divided into fewer vehicle clusters. If it is determined that the total number of vehicles within the preset communication range does not meet the preset numerical requirement, that is, if the minimum number required to form a vehicle cluster is not reached, the preset communication range can be expanded until the total number of vehicles meets the preset numerical requirement, and then a vehicle cluster can be formed to avoid a lack of time data reference due to too few vehicles in the cluster.

[0075] The embodiment of the present application dynamically adjusts the communication range according to the geographic location information and number of vehicles, and can form an effective vehicle cluster, thereby improving the communication efficiency and management capabilities between vehicles.

[0076] Optionally, in a possible embodiment, determining a target vehicle in a vehicle cluster may include:

[0077] S0201. Obtain the node reputation value of each vehicle in the vehicle cluster; the node reputation value is used to indicate the timing stability of the vehicle;

[0078] S0202. Based on the Raft protocol, select the vehicle with the largest node reputation value as the target vehicle in the vehicle cluster.

[0079] For example, to select a target vehicle in a swarm, the node reputation of each vehicle can be obtained. Based on the Raft protocol, the target vehicle is selected based on this node reputation. Node reputation is an indicator of the vehicle's timing stability, which refers to the reliability and accuracy of the vehicle's time synchronization. Node reputation can be calculated based on historical data, the vehicle's hardware capabilities, and network connection quality, among other factors.

[0080] Optionally, in a possible embodiment, obtaining the node reputation value of each vehicle in the vehicle cluster may include:

[0081] S02011. For each vehicle in the vehicle cluster, obtain the vehicle's clock error and communication success rate within a target time period;

[0082] S02012. Perform weighted sum processing on the clock error and the communication success rate to obtain the node reputation value.

[0083] For example, clock error refers to the deviation between the vehicle's internal clock and standard time during a target time period. Smaller clock error indicates more stable and accurate timing capabilities. The communication success rate refers to the ratio of the number of successful communications attempts to the total number of attempts during the target time period. A higher communication success rate indicates more reliable communication capabilities. The target time period can be a predefined window, such as the last two hours or the last 30 minutes.

[0084] For each vehicle in the vehicle cluster, the target vehicle collects the two key indicators of each vehicle's clock error and communication success rate. Then, using the following formula (1), the clock deviation value and communication success rate of each vehicle are weighted and summed to calculate the node reputation value of each vehicle:

[0085] Node reputation value = A × clock error + B × communication success rate (1)

[0086] Where A is the weight corresponding to the clock error, and B is the weight corresponding to the communication success rate. A+B=1. The specific values ​​of A and B can be adjusted according to user needs and are not limited in this embodiment of the application.

[0087] By combining two key metrics, clock error and communication success rate, and performing a weighted summation, we can comprehensively consider the vehicle's timing and communication capabilities to obtain a comprehensive node reputation value. This node reputation value is used to select the most suitable target vehicle in the vehicle cluster. This ensures that the vehicle's time synchronization capabilities and communication reliability are taken into account when selecting the target vehicle in the vehicle cluster, thereby improving the overall performance and stability of the cluster.

[0088] For example, the Raft protocol is an algorithm for achieving consensus in a distributed system, and is typically used to elect a leader node. In an embodiment of the present application, based on the principles of the Raft protocol, the vehicle with the largest node reputation value can be selected as the target vehicle.

[0089] By selecting the vehicle with the highest credibility as the target vehicle, the embodiment of the present application can ensure that there is a node with the best timing stability in the vehicle cluster to coordinate other vehicles, thereby improving the time synchronization accuracy and communication efficiency of the vehicle cluster.

[0090] For example, after a vehicle cluster is constructed and a target vehicle in the vehicle cluster is determined, the target vehicle can send time request information to other vehicles in the vehicle cluster and receive local timestamps fed back by other vehicles, thereby performing time synchronization processing to achieve time synchronization.

[0091] S202 : Determine a time offset value based on the current timestamp of the target vehicle and the local timestamps of each other vehicle; wherein the time offset value is used to indicate the time offset between each vehicle in the vehicle cluster.

[0092] For example, after collecting local timestamps from other vehicles, the target vehicle can calculate a time deviation value based on the target vehicle's current timestamp and the local timestamps of each other vehicle. The time deviation value refers to the time deviation between vehicles in the vehicle cluster, and can be used to quantify the degree of time asynchrony between vehicles in the vehicle cluster.

[0093] Alternatively, in a possible embodiment, determining the time offset value according to the current timestamp of the target vehicle and the local timestamps of each of the other vehicles may include:

[0094] According to the current timestamp of the target vehicle and the local timestamps of all other vehicles, a preset Kalman filter formula is used to calculate the average time deviation value between the vehicles in the vehicle cluster and determine it as the time deviation value.

[0095] For example, the Kalman filter is a recursive algorithm for estimating the state of a dynamic system, particularly suitable for state estimation problems in linear systems. It aims to minimize the mean square error of the estimation error and is widely used in signal processing, control systems, navigation, tracking, and other fields. In the embodiment of the present application, the preset Kalman filter formula can be the following formula (2):

[0096] (2)

[0097] Among them, T in formula (2) i is the local timestamp of the i-th vehicle in the vehicle cluster, T leader is the current timestamp of the target vehicle, and n is the total number of vehicles in the vehicle cluster.

[0098] By substituting the current timestamp of the target vehicle and the local timestamps of all other vehicles into formula (2), the average time offset between the vehicles in the vehicle cluster can be calculated, which is determined as the time offset value of the embodiment of the present application. By presetting the Kalman filter formula, the embodiment of the present application can not only more accurately determine the time offset, thereby achieving more precise time synchronization, but also improve the efficiency and reliability of the time synchronization processing.

[0099] S203. If it is determined that the time deviation value is greater than a preset deviation threshold, a global time error is obtained, and time synchronization processing is performed on each vehicle in the vehicle cluster based on the global time error; wherein the global time error is used to indicate the time deviation between all vehicles in each vehicle cluster.

[0100] For example, based on the calculated time deviation, the target vehicle can determine how to adjust its own clock and the clocks of other vehicles to ensure that the times of all vehicles in the vehicle cluster are as consistent as possible, thereby achieving synchronization and reducing communication and collaboration issues that may arise from time asynchrony. For example, the target vehicle can directly adjust its own clock and the clocks of other vehicles based on the time deviation to achieve time synchronization within the vehicle cluster.

[0101] Exemplarily, the preset deviation threshold is a basis for determining whether a time adjustment is to be performed, and the embodiments of the present application do not limit the specific value of the preset deviation threshold. The target vehicle can first determine whether the time deviation value is greater than the preset deviation threshold, and determine whether a time adjustment is to be performed based on the size of the time deviation value. When it is determined that the time deviation value is less than or equal to the preset deviation threshold, it indicates that the time deviation between the vehicles in the vehicle cluster is small and is not sufficient to affect the normal communication and collaboration between the vehicles. At this time, time synchronization processing may not be performed. When it is determined that the time deviation value is greater than the preset deviation threshold, it indicates that the time deviation between the vehicles in the vehicle cluster is already large and time synchronization processing is required. At this time, the target vehicle can obtain the global time error and perform time synchronization processing on each vehicle in the vehicle cluster based on the global time error.

[0102] Optionally, in a possible embodiment, obtaining the global time error may include:

[0103] S1. Exchanging respective time deviation values ​​with other target vehicles through multi-hop communication; the other target vehicles are target vehicles in other vehicle clusters whose time deviation values ​​are greater than a preset deviation threshold;

[0104] S2. Determine the global time error based on each time deviation value.

[0105] For example, the target vehicle can exchange time deviation values ​​with other target vehicles that also have large time deviations through multi-hop communication, and then determine the global time error based on each time deviation value, and perform time synchronization processing on each vehicle in the vehicle cluster based on the global time error.

[0106] Multi-hop communication is a network communication method in which data is transmitted from a source node to a destination node via multiple intermediate nodes, rather than directly via a single hop. In this embodiment, the transmitted time offset value is forwarded through multiple intermediate nodes within a vehicle cluster (e.g., cluster 1, cluster 2, cluster 3), with randomized hop paths chosen to prevent fixed vehicle locations from exposing vehicle information. Furthermore, the number of data hops can be limited based on actual needs to ensure timely signal transmission, improving data security while also ensuring information security.

[0107] For example, the time deviation values ​​collected by the target vehicle are used to calculate the global time error, which reflects the degree of time asynchrony between all vehicles in the entire vehicle cluster. Adjusting the time of each vehicle in the vehicle cluster based on the global time error can achieve time synchronization for more vehicles and avoid centralization issues.

[0108] Optionally, in order to improve the security of information interaction, in some possible embodiments, before exchanging respective time deviation values ​​with other target vehicles through multi-hop communication, zero-knowledge proof verification can be performed between the target vehicle and the other target vehicles. If the verification is successful, the step of exchanging respective time deviation values ​​with other target vehicles through multi-hop communication is executed.

[0109] For example, Zero-Knowledge Proof (ZKP) is a cryptographic protocol that allows one party (prover) to prove to another party (verifier) ​​the authenticity of a certain information without revealing the specific content of the information. Zero-knowledge proof has important applications in privacy protection and security protocols. In an embodiment of the present application, the target vehicle can generate a zero-knowledge proof to prove that the time deviation value it holds is valid and that its identity is verified. Zero-knowledge proof verification is performed between each target vehicle. After the verification is passed, their respective time deviation values ​​are exchanged through a multi-hop communication mechanism. Since the exchanged information has passed the zero-knowledge proof verification, it is considered to be credible, reducing the risk of malicious vehicles sending false information. In addition, zero-knowledge proof allows vehicles to prove the authenticity of their information without revealing the specific time deviation value, which also protects the privacy of the vehicle.

[0110] Optionally, to improve practicality, an anti-attack fault tolerance mechanism can be designed during the zero-knowledge proof verification process, and the tolerable percentage can be dynamically adjusted based on user needs. For example, the tolerable proportion of malicious node interference can be adjusted by reasonably setting the number of trusted node cross-signatures required during identity verification, and this embodiment of the application does not impose any restrictions on this.

[0111] Optionally, in a possible embodiment, step S2, determining the global time error according to each time deviation value, may include: processing each time deviation value according to a preset global time reference using a preset weighted sum algorithm to obtain the global time error.

[0112] For example, in the context of time synchronization in the present embodiment, a preset weighted summation algorithm can help adjust the time deviation value of each vehicle cluster. For example, the global time error can be determined by the following preset weighted summation algorithm processing formula (3):

[0113] (3)

[0114] Among them, ΔT in formula (3) 全局 is the global time error; ΔΤ i is the time deviation value of the i-th vehicle cluster; T 全局 is the preset global time base; w iis the weight of the i-th vehicle cluster; n is the total number of vehicle clusters. In practical applications, the weight of each vehicle cluster can be determined based on the vehicle density within the vehicle cluster, with the total value being 1, which is not limited in this embodiment of the present application. Vehicle density can be determined by the number of vehicles within the vehicle cluster. For example, a greater number of vehicles and a greater vehicle density correspond to a greater weight. The preset global time reference can be a fixed time reference (such as GPS time) or a time provided by a central node (such as the current time of the target vehicle).

[0115] After the target vehicle in the embodiment of the present application obtains the time deviation value of other vehicle clusters through multi-hop communication exchange, it uses the weighted summation algorithm to process Formula (3) to solve the optimized global time error, which serves as the basis for time synchronization adjustment for all vehicles, thereby improving the accuracy of time synchronization. Through the above method, each vehicle cluster can achieve time synchronization more accurately, improving the efficiency and reliability of collaborative work.

[0116] Optionally, in a possible embodiment, time synchronization processing is performed on each vehicle in a vehicle cluster based on a global time error, which may include: sending synchronization instruction information to other vehicles in the vehicle cluster; wherein the synchronization instruction information includes a global time error, and the synchronization instruction information is used to instruct other vehicles to adjust their local clocks based on the global time error.

[0117] For example, the global time error is the basis for all vehicles to adjust their local clocks. Therefore, the constructed synchronization command message should include the global time error. Furthermore, the synchronization command message may include other necessary information, such as a synchronization timestamp (e.g., the target vehicle's current local timestamp) and the target vehicle's identifier, to ensure the correctness and security of the command. The synchronization command message is then broadcast or multicast to other vehicles in the vehicle cluster. After receiving the synchronization command message, each vehicle reads the global time error and adjusts its local clock accordingly. Adjustments can be made directly, adding or subtracting the global time error to the local clock, or gradually. To avoid system impact, a gradual adjustment strategy can be used to gradually approach the target time.

[0118] By sending synchronization command information, centralized and coordinated time synchronization can be achieved, ensuring that all vehicles are adjusted according to unified standards, achieving efficient and reliable time synchronization, and improving the overall intelligence level and safety.

[0119] Optionally, in order to improve the security of information interaction and avoid vehicle information leakage, all vehicles in the vehicle cluster can be identified by temporary names, and the temporary names are regularly updated through the blockchain. For example, a new temporary name is generated through the blockchain every n minutes, and the old temporary name and associated data are automatically destroyed. n can be set by the user according to actual needs, and this embodiment of the application does not impose any restrictions. The temporary name can be generated using the principle of random number generation, and the temporary name is used to distinguish vehicles. In combination with the blockchain, the temporary name is regularly updated to prevent long-term tracking. In addition, the blockchain is tamper-proof and decentralized, which can further improve the reliability and security of the data.

[0120] Furthermore, to improve information security and prevent privacy leaks, differential privacy noise can be injected into interactive information, such as local timestamps. The amplitude of the differential privacy noise can be dynamically adjusted based on the density of vehicles within the cluster; the more vehicles there are, the greater the noise amplitude. In practical applications, differential privacy signals can be added to the local timestamps fed back by vehicles through the Laplace mechanism, thereby achieving privacy protection.

[0121] The present invention provides a method for time synchronization based on an Internet of Vehicles (IoV) network, which is applied to a target vehicle in a vehicle cluster, comprising multiple vehicles. The method comprises: after establishing a vehicle cluster and determining the target vehicle in the cluster, sending a time request message to other vehicles in the cluster and receiving local timestamps from the other vehicles; determining a time offset value based on the current timestamp of the target vehicle and the local timestamps of each other vehicle; wherein the time offset value indicates the time offset between the vehicles in the cluster; and if the time offset value is greater than a preset offset threshold, obtaining a global time error and performing time synchronization on the vehicles in the cluster based on the global time error; wherein the global time error indicates the time offset between all vehicles in each cluster. By exchanging and synchronizing time information between the target vehicle and other vehicles in the cluster, the degree of time asynchrony between the vehicles is quantified, and effective time synchronization is performed based on the time information. This method not only efficiently achieves time synchronization for all vehicles in any scenario, but also enhances system stability and security. In particular, in autonomous driving and intelligent transportation systems, it can effectively reduce potential misjudgments and delayed responses caused by time asynchrony, thereby improving overall traffic management and user experience.

[0122] For example, Figure 3 This is a flow chart of another method for time synchronization based on the Internet of Vehicles provided in an embodiment of the present application. Figure 3 As shown, the time synchronization method based on the Internet of Vehicles provided in the embodiment of the present application may include:

[0123] S301: The vehicle starts the V2X communication module and detects whether the vehicle's GPS signal is available.

[0124] If not, execute step S302; if so, execute step S303.

[0125] S302: Receive local timestamps broadcast by vehicles within a preset communication range, and determine the total number of vehicles within the preset communication range.

[0126] S303: Enter the traditional timing mode.

[0127] Among them, in the traditional timing mode, the vehicle achieves time synchronization based on a standard time source such as the Global Positioning System GPS.

[0128] S304: Determine whether the total number of vehicles meets a preset numerical requirement.

[0129] If yes, execute step S306; if no, execute step S305.

[0130] S305: Expand the preset communication range until the total number of vehicles meets the preset numerical requirement.

[0131] S306 , dividing according to geographic location information to obtain at least one vehicle cluster.

[0132] S307 : Obtain the node reputation value of each vehicle in the vehicle cluster, and based on the Raft protocol, select the vehicle with the largest node reputation value as the target vehicle in the vehicle cluster.

[0133] S308: Send time request information to other vehicles in the vehicle cluster, and receive local timestamps fed back by other vehicles.

[0134] S309 : Calculate an average time deviation between the vehicles in the vehicle cluster based on the current timestamp of the target vehicle and the local timestamps of the other vehicles using a preset Kalman filter formula, and determine the average time deviation as the time deviation value.

[0135] S310: Determine whether the time deviation value is greater than a preset deviation threshold.

[0136] If yes, execute step S311; if no, execute step S312.

[0137] S311. Exchange respective time deviation values ​​with other target vehicles through multi-hop communication, and process each time deviation value according to a preset global time reference using a preset weighted sum algorithm to obtain a global time error.

[0138] S312: Maintain the current clock.

[0139] S313 : Perform time synchronization processing on each vehicle in the vehicle cluster according to the global time error.

[0140] It should be noted that the specific implementation of the above steps S301 to S313 can refer to other embodiments and will not be repeated here. In actual applications, in order to complete the time synchronization between each vehicle, some or all of the above steps may be included, and the embodiment of this application does not limit it.

[0141] The vehicle network-based time synchronization method provided in the embodiment of the present application constructs a vehicle cluster when it is determined that there is no GPS signal, and exchanges and synchronizes time information between the target vehicle and other vehicles in the vehicle cluster, quantifies the degree of time asynchrony between vehicles, and performs effective time synchronization processing based on this. It can not only efficiently achieve time synchronization of all vehicles in an environment without GPS signals, but also enhance the stability and security of the system. It is suitable for various scenarios with weak GPS signals. For example, it can achieve high-precision time synchronization in complex scenarios such as tunnels and urban canyons, and can meet the different scenario needs of users.

[0142] Figure 4 This is a schematic diagram of the structure of a time synchronization device based on the Internet of Vehicles provided in an embodiment of the present application. The time synchronization device based on the Internet of Vehicles provided in this embodiment is applied to a target vehicle in a vehicle cluster, and the vehicle cluster includes multiple vehicles. Figure 4 As shown, the time synchronization device 40 based on the Internet of Vehicles provided in this embodiment includes a transceiver unit 401 , a calculation unit 402 and a processing unit 403 .

[0143] The transceiver unit 401 is used to send time request information to other vehicles in the vehicle cluster after building the vehicle cluster and determining the target vehicle in the vehicle cluster, and receive local timestamps fed back by other vehicles;

[0144] A calculation unit 402 is configured to determine a time offset value based on the current timestamp of the target vehicle and the local timestamps of each of the other vehicles; wherein the time offset value is used to indicate the time offset between each vehicle in the vehicle cluster;

[0145] The processing unit 403 is configured to obtain a global time error if it is determined that the time deviation value is greater than a preset deviation threshold, and perform time synchronization processing on each vehicle in the vehicle cluster based on the global time error; wherein the global time error is used to indicate the time deviation between all vehicles in each vehicle cluster.

[0146] The device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effects are similar and will not be described in detail in this embodiment.

[0147] In a possible implementation, the computing unit 402 is specifically configured to:

[0148] According to the current timestamp of the target vehicle and the local timestamps of all other vehicles, a preset Kalman filter formula is used to calculate the average time deviation value between the vehicles in the vehicle cluster and determine it as the time deviation value.

[0149] In a possible implementation, the processing unit 403 is specifically configured to:

[0150] exchanging respective time deviation values ​​with other target vehicles through multi-hop communication; the other target vehicles are target vehicles in other vehicle clusters whose time deviation values ​​are greater than a preset deviation threshold;

[0151] According to each time deviation value, the global time error is determined.

[0152] In a possible implementation, the processing unit 403 is specifically configured to:

[0153] According to the preset global time reference, each time deviation value is processed using a preset weighted summation algorithm to obtain a global time error.

[0154] In a possible implementation, the processing unit 403 is specifically configured to:

[0155] Send synchronization instruction information to other vehicles in the vehicle cluster; wherein the synchronization instruction information includes a global time error, and the synchronization instruction information is used to instruct other vehicles to adjust their local clocks according to the global time error.

[0156] In a possible implementation, the processing unit 403, before exchanging respective time offset values ​​with other target vehicles through multi-hop communication, is further configured to:

[0157] A zero-knowledge proof verification is performed between the target vehicle and other target vehicles. If the verification is successful, the steps of exchanging respective time offset values ​​with other target vehicles through multi-hop communication are executed.

[0158] In a possible implementation, before sending the time request information to other vehicles in the vehicle cluster, the transceiver unit 401 is further configured to:

[0159] Check whether the GPS signal of the vehicle is available;

[0160] If not available, a vehicle cluster is constructed and the target vehicle in the vehicle cluster is determined.

[0161] In a possible implementation, the transceiver unit 401 is specifically configured to:

[0162] Receive local timestamps broadcast by vehicles within a preset communication range and determine the total number of vehicles within the preset communication range; the local timestamps include geographic location information;

[0163] If it is determined that the total number of vehicles meets the preset numerical requirements, then the vehicles are divided according to the geographical location information to obtain at least one vehicle cluster;

[0164] If it is determined that the total number of vehicles does not meet the preset numerical requirement, the preset communication range is expanded until the total number of vehicles meets the preset numerical requirement.

[0165] In a possible implementation, the transceiver unit 401 is specifically configured to:

[0166] Obtain the node reputation value of each vehicle in the vehicle cluster; the node reputation value is used to indicate the timing stability of the vehicle;

[0167] Based on the Raft protocol, the vehicle with the largest node reputation value is selected as the target vehicle in the vehicle cluster.

[0168] In a possible implementation, the transceiver unit 401 is specifically configured to:

[0169] For each vehicle in the vehicle cluster, obtain the vehicle's clock error and communication success rate within the target time period;

[0170] The clock error and communication success rate are weighted and summed to obtain the node reputation value.

[0171] In one possible implementation, vehicles in a vehicle cluster are identified using temporary names, and the temporary names are regularly updated through the blockchain; and / or differential privacy noise is injected into the local timestamp.

[0172] The device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effects are similar and will not be described in detail in this embodiment.

[0173] It should be noted that it should be understood that the division of the various modules of the above device is merely a division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. Moreover, these modules can all be implemented in the form of software called by processing elements; they can also all be implemented in the form of hardware; some modules can also be implemented in the form of software called by processing elements, and some modules can be implemented in the form of hardware. In addition, they can also be stored in the memory of the above device in the form of program code, and called and executed by a processing element of the above device. The implementation of other modules is similar. In addition, these modules can all or partly be integrated together, or they can be implemented independently. The processing element here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above modules can be completed by the hardware integrated logic circuit in the processor element or by instructions in the form of software.

[0174] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 5 As shown, the electronic device 50 provided in this embodiment includes: at least one processor 501 and a memory 502. Optionally, the device 50 further includes a communication component 503. The processor 501, the memory 502 and the communication component 503 are connected via a bus 504.

[0175] In a specific implementation process, at least one processor 501 executes the computer-executable instructions stored in the memory 502, so that the at least one processor 501 performs the above method.

[0176] The specific implementation process of the processor 501 can be found in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here in this embodiment.

[0177] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASICs), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0178] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage.

[0179] A bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0180] The present application also provides a vehicle, comprising the electronic device of the above embodiment.

[0181] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0182] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0183] The readable storage medium may be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0184] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0185] The division of units is merely a logical functional division; actual implementations may employ alternative divisions, such as combining or integrating multiple units or components into another system, or omitting or disabling certain features. Furthermore, any direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units, either through an interface, electrical, mechanical, or other means.

[0186] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0187] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0188] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the method of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0189] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0190] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A time synchronization method based on the Internet of Vehicles, characterized in that: The method is applied to a target vehicle in a vehicle cluster, where the vehicle cluster includes multiple vehicles, and includes: After building a vehicle cluster and determining a target vehicle in the vehicle cluster, sending a time request message to other vehicles in the vehicle cluster and receiving local timestamps fed back by the other vehicles; Determining a time offset value based on the current timestamp of the target vehicle and the local timestamps of each of the other vehicles; wherein the time offset value is used to indicate the time offset between the vehicles in the vehicle cluster; If it is determined that the time deviation value is greater than the preset deviation threshold, exchanging respective time deviation values ​​with other target vehicles through multi-hop communication; the other target vehicles are target vehicles in other vehicle clusters whose time deviation values ​​are greater than the preset deviation threshold; According to a preset global time reference, each of the time deviation values ​​is processed using a preset weighted sum algorithm to obtain a global time error; wherein the global time error is used to indicate the time deviation between all vehicles in each vehicle cluster; Sending synchronization instruction information to other vehicles in the vehicle cluster; wherein the synchronization instruction information includes the global time error, and the synchronization instruction information is used to instruct the other vehicles to adjust local clocks according to the global time error.

2. The method according to claim 1, characterized in that The determining of the time offset value according to the current timestamp of the target vehicle and the local timestamps of each of the other vehicles includes: According to the current timestamp of the target vehicle and the local timestamps of each of the other vehicles, a preset Kalman filter formula is used to calculate an average time deviation value between the vehicles in the vehicle cluster, and determine it as the time deviation value.

3. The method according to claim 1, characterized in that Before exchanging respective time offset values ​​with other target vehicles through multi-hop communication, the method further includes: A zero-knowledge proof verification is performed between the target vehicle and the other target vehicles. If the verification is successful, a step of exchanging respective time offset values ​​with the other target vehicles through multi-hop communication is executed.

4. The method according to any one of claims 1 to 3, characterized in that Before sending the time request information to other vehicles in the vehicle cluster, the method further includes: Check whether the GPS signal of the vehicle is available; If not available, a vehicle cluster is constructed and the target vehicle in the vehicle cluster is determined.

5. The method according to claim 4, characterized in that The building of the vehicle cluster includes: Receiving local timestamps broadcast by vehicles within a preset communication range and determining the total number of vehicles within the preset communication range; the local timestamps including geographic location information; If it is determined that the total number of vehicles meets the preset numerical requirement, dividing the vehicles according to the geographical location information to obtain at least one vehicle cluster; If it is determined that the total number of vehicles does not meet the preset numerical requirement, the preset communication range is expanded until the total number of vehicles meets the preset numerical requirement.

6. The method according to claim 4, characterized in that The determining of the target vehicle in the vehicle cluster includes: Obtaining a node reputation value of each vehicle in the vehicle cluster; the node reputation value is used to indicate the timing stability of the vehicle; Based on the Raft protocol, the vehicle with the largest node reputation value is selected as the target vehicle in the vehicle cluster.

7. The method according to claim 6, characterized in that The obtaining of the node reputation value of each vehicle in the vehicle cluster includes: For each vehicle in the vehicle cluster, obtaining a clock error and a communication success rate of the vehicle within a target time period; A weighted summation process is performed on the clock error and the communication success rate to obtain the node reputation value.

8. The method according to any one of claims 1 to 3, characterized in that Vehicles in the vehicle cluster are identified using temporary names, and the temporary names are regularly updated through the blockchain; and / or differential privacy noise is injected into the local timestamp.

9. A time synchronization device based on the Internet of Vehicles, characterized in that: The device is applied to a target vehicle in a vehicle cluster, where the vehicle cluster includes multiple vehicles, and includes: A transceiver unit is configured to, after building a vehicle cluster and determining a target vehicle in the vehicle cluster, send time request information to other vehicles in the vehicle cluster and receive local timestamps fed back by the other vehicles; a calculation unit, configured to determine a time offset value based on a current timestamp of the target vehicle and a local timestamp of each of the other vehicles; wherein the time offset value is used to indicate a time offset between the vehicles in the vehicle cluster; A processing unit is configured to exchange respective time deviation values ​​with other target vehicles through multi-hop communication if it is determined that the time deviation value is greater than a preset deviation threshold; the other target vehicles are target vehicles in other vehicle clusters whose time deviation values ​​are greater than the preset deviation threshold; based on a preset global time reference, each of the time deviation values ​​is processed using a preset weighted sum algorithm to obtain a global time error; wherein the global time error is used to indicate the time deviation between all vehicles in each vehicle cluster; and send synchronization instruction information to other vehicles in the vehicle cluster; wherein the synchronization instruction information includes the global time error, and the synchronization instruction information is used to instruct the other vehicles to adjust their local clocks according to the global time error.

10. An electronic device, characterized in that: include: Memory, processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method according to any one of claims 1 to 8.

11. A vehicle, characterized in that: Comprising the electronic device as claimed in claim 10.

12. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 8 when executed by a processor.

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