A method and system for vehicle communication based on multi-point network priority awareness

Abstract

The application relates to a kind of vehicle-mounted communication method and system based on multi-point network priority perception, comprising: initialization configuration is carried out to vehicle-mounted multi-point communication network;Each node in network selects this sending object according to the priority order of to-be-sent message, extracts operating state information variable encapsulated in to-be-sent message, and is transmitted to vehicle-mounted multi-point communication network in transmission opportunity window;Each node real-time analysis operating state information variable of received message, obtains the distribution state of global priority message, and decides to send or keep silent in transmission opportunity window according to global priority relationship;In the process of vehicle-mounted multi-point communication network operation, the traffic load condition of each node is counted, and the node identifier of each node is dynamically adjusted according to the traffic load condition, so that the node completes message sending in the PLCA mechanism according to the updated node identifier order.Compared with the prior art, the transmission certainty of high-priority message is significantly improved while maintaining standard compatibility.

Description

Technical Field

[0001] This invention relates to the field of vehicle communication technology, and in particular to a vehicle communication method and system based on multi-point network priority awareness. Background Technology

[0002] As vehicle electronic and electrical architecture evolves towards centralization and regional controllers, vehicle communication networks are gradually migrating from traditional bus technologies such as CAN and LIN to Ethernet technology. Compared to traditional vehicle buses, vehicle Ethernet has significant advantages in bandwidth capacity, protocol standardization, and software and hardware ecosystem compatibility, and has gradually become the basic communication technology connecting central computing platforms, regional controllers, and various edge nodes.

[0003] In a typical regional centralized vehicle network architecture, the central computing platform is connected to multiple regional controllers via high-speed Ethernet. Each regional controller is responsible for the management and control of edge nodes such as actuators, sensors, and functional modules within its coverage area. To reduce the complexity of wiring within the area and control system costs, a bus topology is typically used between the regional controller and its subordinate edge nodes, and the edge network within the area is constructed through multi-point shared media communication. For the above application scenario, the IEEE 802.3cg standard defines 10BASE-T1S single-pair Ethernet physical layer technology, enabling multiple nodes to communicate via Ethernet through the same single-pair physical medium, thereby effectively reducing the number of wiring harnesses and interface resource consumption. In this type of vehicle communication network, multiple edge nodes can access the regional controller through a 10BASE-T1S multi-point network.

[0004] Since 10BASE-T1S uses a multi-node shared medium communication method, in order to avoid signal collisions caused by multiple nodes sending simultaneously, the standard introduces a physical layer collision avoidance mechanism (PLCA). This mechanism coordinates medium access through a polling method based on node identifiers, thereby achieving orderly and fair access for each node in a multi-point network.

[0005] However, in practical vehicle applications, each node often simultaneously carries multiple types of service messages with different real-time requirements. Some of these high-real-time services have strict requirements on message transmission latency and jitter. The existing PLCA mechanism only schedules media access based on the node identifier order, failing to perceive and distinguish the priority characteristics of different messages at the multi-point shared media level. The transmission latency of high-priority messages is easily affected by polling order and network load changes, thus limiting the effectiveness of 10BASE-T1S multi-point networks in time-sensitive vehicle application scenarios to some extent.

[0006] Currently, in the vehicle-mounted 10BASE-T1S multi-point Ethernet communication scheme based on the Physical Layer Collision Avoidance (PLCA) mechanism in the IEEE 802.3cg standard, multiple network nodes communicate with the upper-level control node by sharing the same single-pair physical medium. PLCA, as a physical layer medium access coordination mechanism, is used to avoid signal conflicts caused by multiple nodes sending simultaneously in a multi-point network environment.

[0007] The PLCA mechanism organizes communication on a shared medium across multiple points using a polling method at the coordination layer. Each PLCA polling cycle is triggered by a beacon signal sent by the coordinating node to synchronize the polling status of each node. Subsequently, each node advances its transmission opportunity count according to a pre-configured node identifier and a unified polling order. When the polling count matches the node's own identifier, the corresponding node enters its transmission opportunity window. If a node has no data to send, it remains silent and quickly relinquishes its transmission opportunity; in this case, the media time it occupies corresponds to the minimum time slice. If a node has data to send, it can complete the transmission of the data frame within the transmission opportunity window by submitting a signal; the media time it occupies varies with the data frame length. When a node sends the maximum-length data frame, its media time reaches the maximum time slice. Thus, when all nodes send the maximum-length data within a PLCA polling cycle, the time slices corresponding to each node reach their maximum values, forming the maximum PLCA polling cycle; conversely, when all nodes remain silent within a polling cycle, the time slices corresponding to each node are at their minimum values, forming the minimum PLCA polling cycle.

[0008] Through the above mechanism, PLCA can ensure that only one node occupies the shared medium at any given time, thus achieving collision-free communication between multiple nodes without modifying the Ethernet MAC protocol. However, this mechanism is essentially a polling access method based on node identifier order. Its transmission order is determined solely by the node identifier and is not directly related to the priority characteristics of the node's service traffic. In time-sensitive service scenarios, the transmission latency and jitter of high-priority traffic are still easily affected by changes in polling order and network load, making it difficult to obtain stable deterministic transmission guarantees.

[0009] To address the varying communication performance requirements of different service traffic in multi-point shared media environments, some research and engineering implementations have attempted to extend existing PLCA mechanisms by modifying the PLCA state machine, introducing interrupt triggering mechanisms, or adopting preemptive transmission strategies to improve communication latency performance in specific scenarios. However, such solutions typically require intrusive modifications to the existing workflow or physical layer behavior of PLCA, making it difficult to achieve unified deployment while maintaining compatibility with the IEEE 802.3cg standard protocol, and also hindering interoperability between cross-vendor devices.

[0010] Therefore, while maintaining the existing working mode of the 10BASE-T1S physical layer characteristics and PLCA mechanism, how to introduce network-level perception and transmission control capabilities oriented towards message priority to improve the transmission determinism of high-priority messages in a multi-point shared medium environment has become a key technical problem faced by vehicular multi-point Ethernet in carrying time-sensitive service scenarios. Summary of the Invention

[0011] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a vehicle communication method and system based on multi-point network priority awareness, which improves the determinism of high-priority message transmission in a multi-point shared medium environment while maintaining the existing working mode of 10BASE-T1S physical layer characteristics and PLCA mechanism.

[0012] The objective of this invention can be achieved through the following technical solutions: A vehicle communication method based on multi-point network priority awareness includes: S1: Initialize the configuration of the vehicle-mounted multi-point communication network. The initialization configuration includes the basic configuration and runtime environment initialization of each node in the vehicle-mounted multi-point communication network by executing the PLCA mechanism. The runtime environment initialization includes establishing a multi-level priority sending queue structure inside the node and initializing runtime information variables. The runtime information variables include priority queue occupancy status, node identifier, and node order reordering request information. S2: Each node determines whether there is a message to be sent in its internal priority sending queue. If there is a message to be sent, the target to be sent is selected according to the priority order, the corresponding runtime information variables are extracted and encapsulated in the message to be sent, and transmitted to the vehicle multipoint communication network within the sending opportunity window. S3: Each node analyzes the runtime information variables of the messages in the vehicle multi-point communication network in real time, obtains the distribution status of priority messages in the entire network, and decides to send or remain silent within the sending opportunity window determined by the PLCA mechanism based on the global priority relationship. S4: During the operation of the vehicle-mounted multi-point communication network, the traffic load of each node is statistically analyzed, and the node identifier of each node is dynamically adjusted accordingly, so that the nodes complete the message transmission under the PLCA mechanism according to the updated node identifier order.

[0013] Furthermore, in step S1, the initialization process of the node identifier includes: initializing and allocating node identifiers for each node according to preset network planning parameters or evaluation results of node traffic load characteristics.

[0014] Furthermore, in step S2, determining whether there are any messages to be sent in the internal priority sending queue includes: The node polls each priority sending queue in order of priority to determine if there is a message to be sent. If there is no message to be sent in the node, the node maintains its current state and continues to poll the queue. If there is a message to be sent in the node, the message to be sent from the highest priority sending queue among the non-empty priority sending queues is selected as the target for this transmission.

[0015] Furthermore, in step S2, the corresponding runtime information variables are extracted and encapsulated in the message to be sent, including: The runtime information variables are written into the PLCA information domain structure, which includes a node identifier field, a node reordering request indication field, and a priority queue occupancy status field. These fields are used to store the node identifier, node reordering request information, and priority queue occupancy status, respectively. The priority queue occupancy status field represents the occupancy status of each priority queue in the form of a bit vector. The PLCA information domain structure is encapsulated in the message to be sent for transmission.

[0016] Furthermore, in step S3, each node parses the runtime information variables of the messages in the vehicular multi-point communication network in real time, including: After receiving messages from the vehicle-mounted multipoint communication network through the PLCA mechanism, each node parses the PLCA information field structure carried in the message and obtains the node identifier, node order reordering request information and priority queue occupancy status to obtain running state information variables.

[0017] Furthermore, in step S3, obtaining the distribution status of priority messages across the entire network and deciding whether to send or remain silent within the sending opportunity window determined by the PLCA mechanism based on the global priority relationship includes: Before the current node's message enters the sending opportunity window, it determines whether there are other nodes in the multi-point communication network with higher priority messages to be sent. If not, the current node sends the message within the sending opportunity window; if so, the current node enters a silent state, skips the current sending opportunity window, and accumulates the number of consecutive silent states. When the number of silent states exceeds a preset silent threshold, the corresponding node's silent state is canceled, and the message is sent within the current sending opportunity window.

[0018] Furthermore, step S3 also includes: when a node sends a message, determining whether there are multiple messages to be sent in the highest priority non-empty priority sending queue within the node; if so, enabling continuous sending mode within the corresponding sending opportunity window and sending the multiple messages to be sent in a burst manner; otherwise, sending a single message in the normal sending mode within the corresponding sending opportunity window.

[0019] Furthermore, step S4 includes the following sub-steps: S41: When the vehicle-mounted multi-point communication network starts running, an initial traffic statistics period timer is configured for each node to continuously determine whether the preset statistics period has expired; if it has not expired, the number of messages sent by different priority sending queues within the node is continuously accumulated and counted; if it has expired, the statistics window of the traffic statistics period timer is updated by sliding, and the node traffic load weight value of the corresponding node is calculated based on the number of messages sent by the priority sending queue. S42: Sort all nodes in the vehicle multipoint communication network according to the node traffic load weight value of each node, so as to determine the node identifier update value of each node; if the node identifier of each node has not changed in the current statistical period, directly enter the next statistical period and return to step S41; otherwise, use the node identifier update value of each node as the candidate node identifier corresponding to each node, enter the next statistical period and return to step S41. S43: If the runtime information variable obtained in step S3 is set, a node reordering request event is triggered. This node reordering request event compares the candidate node identifier of each node with the current node identifier. If they are the same, the node reordering request event is ignored. If they are different, the corresponding node enters the waiting stage until it receives the beacon signal of the next PLCA mechanism execution cycle, and updates the node identifier of each node in the vehicle multipoint communication network to the corresponding candidate node identifier.

[0020] Furthermore, the expression for calculating the node traffic load weight value is as follows: In the formula, For the first The node traffic load weight value of each node in the current statistical period. Send queue index for priority, The maximum priority index for the priority sending queue. Indicates priority as The weight coefficient corresponding to the priority sending queue. For the current statistical period, the first Each node has a priority of The number of packets actually sent in the priority sending queue.

[0021] The present invention also provides a vehicle communication system based on multi-point network priority awareness, including a memory and a processor. The memory stores a computer program, and the processor calls the computer program to execute the steps of the method described above.

[0022] Compared with the prior art, the present invention has the following advantages: (1) Compared with the prior art, where each node only schedules based on local information, the present invention extracts the running state information such as priority queue occupancy status from the node and encapsulates it and propagates it in the multi-point network with Ethernet packets. This enables each node to perceive the priority queue occupancy status of other nodes in the network, thereby forming an overall understanding of the packet priority distribution in a shared medium environment, providing basic support for subsequent transmission control and polling optimization.

[0023] (2) In the operation of PLCA, the present invention introduces a transmission control strategy based on network-level priority awareness, which enables nodes to decide whether to send or remain silent based on global priority information within their transmission opportunity window. When it is determined that it has the highest priority message to be sent in the current network, it selects single-frame or continuous transmission mode to complete the transmission based on the number of messages in the highest priority queue. Thus, without changing the PLCA polling mechanism, high-priority messages can obtain priority transmission opportunities in the shared medium access process, effectively reducing their transmission waiting delay and improving the deterministic performance of time-sensitive traffic in multi-point networks.

[0024] (3) This invention obtains the traffic load weight by weighting the message sending status of nodes within the statistical period, and generates the node identifier order to be updated accordingly, so that the sending opportunity allocation can be adaptively optimized as the high-priority traffic load changes, so that the nodes carrying high-priority traffic load are in a more advantageous position in subsequent PLCA polling, thereby enhancing the system's adaptability to dynamic traffic load scenarios and improving the overall operating efficiency of the system in dynamic scenarios.

[0025] (4) All of the above-mentioned technical means of this invention are proposed on the premise of maintaining compatibility with the PLCA protocol in the IEEE 802.3cg standard. This invention does not change the media access coordination rules, polling transmission timing and basic operating behavior specified by the PLCA mechanism. Therefore, there is no need to make intrusive modifications to the existing PLCA mechanism, so it can be directly adapted to the existing vehicle 10BASE-T1S multi-point network architecture, which is conducive to system integration and deployment, and supports interoperability between cross-vendor devices. Attached Figure Description

[0026] Figure 1 This is a flowchart illustrating a vehicle communication method based on multi-point network priority awareness provided in an embodiment of the present invention. Figure 2 This is a schematic diagram showing the structure and location of a PLCA information field in an Ethernet frame, as provided in an embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] Example 1 like Figure 1 As shown, this invention discloses a vehicle-mounted communication method based on multi-point network priority awareness. While maintaining compatibility with the PLCA protocol in the IEEE 802.3cg standard, it introduces runtime information awareness and transmission control strategies at the node side to ensure priority transmission of high-priority messages and dynamically adaptively adjust the node polling order. The method generally includes the following steps: S1 vehicle-mounted 10BASE-T1S multipoint network system initialization: Initialize the vehicle-mounted multipoint communication network. This initialization configuration includes the basic configuration and runtime environment initialization of each node in the vehicle-mounted multipoint communication network using the PLCA mechanism. The runtime environment initialization includes establishing a multi-level priority transmission queue structure within the node and initializing runtime information variables, including priority queue occupancy status, node identifier, and node order reordering request information. S2 node runtime information extraction, encapsulation and transmission: Each node determines whether there is a message to be sent in its internal priority sending queue. If there is a message to be sent, the target to be sent is selected according to the priority order, the corresponding runtime information variables are extracted and encapsulated in the message to be sent, and transmitted to the vehicle multi-point communication network within the sending opportunity window. S3 Priority transmission control based on node runtime awareness: Each node analyzes the runtime information variables of the messages in the vehicle multi-point communication network in real time, obtains the distribution status of priority messages in the entire network, and decides to send or remain silent within the transmission opportunity window determined by the PLCA mechanism based on the global priority relationship. S4 Dynamic Adjustment of Node Identifiers Based on Traffic Load Weight: During the operation of the vehicle-mounted multi-point communication network, the traffic load of each node is statistically analyzed to dynamically adjust the node identifier of each node, so that nodes with heavier traffic loads are given a higher transmission order.

[0031] The following is a detailed description of each step: 1. Initialization of S1 vehicle-mounted 10Base-T1S multi-point network system Step S1 is used to initialize and configure the network communication mechanism and the operating environment of each node during the startup phase of the vehicle-mounted 10BASE-T1S multi-point network, providing basic support for subsequent PLC-based communication and priority-aware transmission control. It specifically includes the following sub-steps: S11: PLCA mechanism initialization. Each node completes the initial node identifier allocation based on the preset network planning parameters or the evaluation results of node traffic load characteristics; then, the PLCA mechanism is configured in a basic manner, which includes at least the total number of network nodes, node identifier parameters, and transmission opportunity window size, and the PLCA function is enabled, so that each node can participate in the access and communication of the 10BASE-T1S multipoint network according to the PLCA mechanism.

[0032] S12: Priority-Aware Method Runtime Environment Initialization. Each node initializes the runtime environment to support priority-aware transmission control. A multi-level priority transmission queue structure is established within the node for classifying, storing, and managing packets of different priorities. Simultaneously, node runtime information variables are initialized, including at least the priority queue occupancy status, node identifier, and node reordering request information. Furthermore, a node information table is established on the node side to maintain the runtime information of each node in the 10BASE-T1S multi-point network, and a periodic timer is initialized to statistically analyze and update the traffic information of each node within a statistical period.

[0033] like Figure 2 As shown, the PLCA information field structure is used to cache the aforementioned runtime information variables. Its fields include at least a node identifier field, a node reordering request indication field, and a priority queue occupancy status field. The priority queue occupancy status field represents the occupancy status of each priority queue in bit vector form; a bit value of 0 indicates that the corresponding priority queue is empty, and a bit value of 1 indicates that there is a message to be sent in the corresponding priority queue. The PLCA information field is dynamically filled during subsequent transmission and sent along with the Ethernet message to achieve the sharing of node runtime information variables in the 10BASE-T1S multipoint network.

[0034] 2. Extraction, encapsulation, and transmission of runtime information variables for the S2 node. Step S2 is used to obtain the node's running state information variables when there are messages to be sent on the node, including priority queue occupancy status, node identifier, and node order reordering request information, and update the PLCA information field based on the running state information variables. Specifically, it includes the following sub-steps: S21: Priority Queue Polling. The node polls its internal multiple priority sending queues according to a strict priority strategy to determine whether there is a message to be sent. When there is no message to be sent, the node maintains its current state and continues to poll the queues. When there is a message to be sent, the node selects the highest priority message from the current non-empty priority queue as the message to be sent.

[0035] S22: Extraction of node runtime information variables. The node obtains its local node identifier. The node obtains the occupancy status of each priority queue; simultaneously, the node obtains the candidate node identifiers output in step S42. and associate it with the local node identifier. Comparison. When and When they are different, the node order reordering request flags are set; when and If they are the same, clear the node order rearrangement request flag.

[0036] S23: The PLCA information field is encapsulated into the Ethernet message. The node writes runtime information variables, including the local node identifier, priority queue occupancy status, and node reordering request flag, into the PLCA information field, and encapsulates the PLCA information field into the message to be sent. Then, the transmission silence control and burst transmission control processes described in steps S33 and S34 are entered.

[0037] 3. S3 Priority transmission control based on node runtime awareness Step S3 is used to control the sending behavior of this node within the sending opportunity window during PLCA operation, based on the real-time perception results of the operational status information variables of each node in the 10BASE-T1S multipoint network, thereby providing priority sending opportunities for high-priority messages in the shared medium environment. The step specifically includes the following sub-steps: S31: Parsing of runtime information variables of the sending node. After receiving an Ethernet packet from the 10BASE-T1S multipoint network, the node parses the PLCA information field carried in the Ethernet packet to obtain the node identifier, priority queue occupancy status, and node reordering request flag of the sending node.

[0038] S32: Node information and traffic statistics update. The node updates the node information table based on the running state information variables of the sending node obtained from step S31, and synchronously updates the traffic statistics of each node within the statistical period; when the node reordering request flag is detected to be set, the node records the corresponding node reordering request event and triggers the execution of step S43.

[0039] S33: Transmission Silence Control Based on Global Message Priority Relationships. Before entering the current node's transmission opportunity window, the node comprehensively judges the priority queue occupancy status of other nodes in the 10BASE-T1S multipoint network based on the currently maintained node information table to determine whether there are other nodes with higher-priority messages to be transmitted. When there are no higher-priority messages to be transmitted, the node is allowed to transmit messages within the current transmission opportunity window; when there are other nodes with higher-priority messages to be transmitted, the current node enters a silence state, skips the current transmission opportunity window, and accumulates a continuous silence count; when the continuous silence count exceeds a preset threshold, the node cancels the silence state, resumes normal transmission mode, and transmits messages within the current transmission opportunity window.

[0040] S34: Burst transmission control based on the highest priority queue status. The node determines whether there are multiple messages to be sent in its highest priority non-empty queue. When the condition is met, the node enables continuous transmission mode within the current transmission opportunity window and sends the high-priority messages in a burst manner. When the condition is not met, the node sends a single message within the current transmission opportunity window according to the normal transmission mode. After completing this transmission, the node resets the continuous silence count to zero.

[0041] 4. S4 dynamically adjusts node identifiers based on traffic load weight. Step S4 is used to dynamically adjust the node identifier of each node in the 10BASE-T1S multipoint network based on the traffic load of each node within the statistical period during network operation, so that nodes carrying heavy high-priority traffic loads can obtain a higher sending order in subsequent PLCA polling processes. Specifically, it includes the following sub-steps.

[0042] S41: Node Traffic Load Weight Calculation. The node initializes a traffic statistics period timer and continuously checks whether the statistics period has expired during network operation. Within the statistics period, the node accumulates statistics on the number of packets sent by each node in the 10BASE-T1S multipoint network on different priority queues. This statistical process is implemented in step S32. When the statistics period expires, the node reads the traffic statistics information for the current statistics period and updates the statistics window by sliding.

[0043] Subsequently, based on preset priority weighting coefficients, the nodes perform weighted calculations on the number of packets sent by each node in different priority queues within the statistical period to obtain the corresponding node traffic load weight value. The calculation method is as follows: in, Indicates the first The traffic load weight of each node in the current statistical period; This represents the priority queue index, with a value ranging from 0 to 7; Representation and Priority The corresponding weighting coefficients are used to reflect the importance of traffic with different priorities; This indicates that within the statistical period, the first... Each node has a priority of The number of messages actually sent in the queue.

[0044] S42: Node identifier candidate value calculation. Each node calculates its traffic load weight based on the results obtained in step S41. All nodes are sorted, with higher traffic load weight values ​​corresponding to higher node priority, and lower node identifier values. Since node traffic statistics are globally perceptible information in the network, all nodes receive consistent rankings based on the same statistical results. When the node traffic load weight ranking calculated within the current statistical period remains unchanged compared to the previous period, the node directly enters the next statistical period after the sliding statistical window. When the ranking changes, the node calculates its corresponding candidate node identifier based on the new ranking result. And then proceed to the next statistical period.

[0045] S43: Node identifier synchronization update. After receiving the node order reordering request from step S31, the node obtains the candidate node identifier generated in step S42. and compare it with the current local node identifier. Comparison. When and When they are the same, the node ignores the current node order adjustment request; when and At the same time, nodes enter a waiting state until they receive the beacon signal for the next PLCA cycle. When a new PLCA cycle begins, all nodes in the network synchronously update their local node identifiers to the corresponding candidate node identifiers. This ensures that the new node identifier order takes effect uniformly in subsequent PLCA cycles.

[0046] This embodiment also provides a vehicle communication system based on multi-point network priority awareness, including a memory and a processor. The memory stores a computer program, and the processor calls the computer program to execute the steps of the vehicle communication method based on multi-point network priority awareness as described above.

[0047] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for priority-aware vehicular communication based on a multi-point network, characterized in that, include: S1: Initialize the configuration of the vehicle-mounted multi-point communication network. The initialization configuration includes the basic configuration and runtime environment initialization of each node in the vehicle-mounted multi-point communication network by executing the PLCA mechanism. The runtime environment initialization includes establishing a multi-level priority sending queue structure inside the node and initializing runtime information variables. The runtime information variables include priority queue occupancy status, node identifier, and node order reordering request information. S2: Each node determines whether there is a message to be sent in its internal priority sending queue. If there is a message to be sent, the target to be sent is selected according to the priority order, the corresponding runtime information variables are extracted and encapsulated in the message to be sent, and transmitted to the vehicle multipoint communication network within the sending opportunity window. S3: Each node analyzes the runtime information variables of the messages in the vehicle multi-point communication network in real time, obtains the distribution status of priority messages in the entire network, and decides to send or remain silent within the sending opportunity window determined by the PLCA mechanism based on the global priority relationship. S4: During the operation of the vehicle-mounted multi-point communication network, the traffic load of each node is statistically analyzed, and the node identifier of each node is dynamically adjusted accordingly, so that the nodes complete the message transmission under the PLCA mechanism according to the updated node identifier order. In step S3, obtaining the distribution status of priority packets across the entire network and deciding whether to send or remain silent within the sending opportunity window determined by the PLCA mechanism based on the global priority relationship includes: Before the current node's message enters the sending opportunity window, it determines whether there are other nodes in the multi-point communication network with higher priority messages to be sent. If not, the current node sends the message within the sending opportunity window; if so, the current node enters a silent state, skips the current sending opportunity window, and accumulates the number of consecutive silent states. When the number of silent states exceeds a preset silent threshold, the corresponding node's silent state is canceled, and the message is sent within the current sending opportunity window.

2. The method according to claim 1, wherein, In step S1, the initialization process of the node identifier includes: initializing and allocating node identifiers for each node according to preset network planning parameters or evaluation results of node traffic load characteristics.

3. The method of claim 1, wherein, In step S2, determining whether there are any messages to be sent in the internal priority sending queue includes: The node polls each priority sending queue in order of priority to determine if there is a message to be sent. If there is no message to be sent in the node, the node maintains its current state and continues to poll the queue. If there is a message to be sent in the node, the message to be sent from the highest priority sending queue among the non-empty priority sending queues is selected as the target for this transmission.

4. The method of claim 1, wherein, In step S2, the corresponding runtime information variables are extracted and encapsulated in the message to be sent, including: The runtime information variables are written into the PLCA information domain structure, which includes a node identifier field, a node reordering request indication field, and a priority queue occupancy status field. These fields are used to store the node identifier, node reordering request information, and priority queue occupancy status, respectively. The priority queue occupancy status field represents the occupancy status of each priority queue in the form of a bit vector. The PLCA information domain structure is encapsulated in the message to be sent for transmission.

5. The method of claim 4, wherein, In step S3, each node parses the runtime information variables of the packets in the vehicle-mounted multi-point communication network in real time, including: After receiving messages from the vehicle-mounted multipoint communication network through the PLCA mechanism, each node parses the PLCA information field structure carried in the message and obtains the node identifier, node order reordering request information and priority queue occupancy status to obtain running state information variables.

6. The method of claim 1, wherein, Step S3 further includes: when a node sends a message, determining whether there are multiple messages to be sent in the highest priority non-empty priority sending queue within the node; if so, enabling continuous sending mode within the corresponding sending opportunity window and sending the multiple messages to be sent in a burst manner; otherwise, sending a single message in the normal sending mode within the corresponding sending opportunity window.

7. The method of claim 1, wherein, Step S4 includes the following sub-steps: S41: When the vehicle-mounted multi-point communication network starts running, configure an initial traffic statistics period timer for each node to continuously determine whether the preset statistics period has expired; if it has not expired, continuously accumulate and count the number of messages sent by different priority sending queues within the node. If the deadline is reached, the statistical window of the traffic statistics period timer will be updated by sliding, and the node traffic load weight value of the corresponding node will be calculated based on the number of messages sent in the priority sending queue. S42: Sort all nodes in the vehicle multipoint communication network according to the node traffic load weight value of each node, so as to determine the node identifier update value of each node; if the node identifier of each node has not changed in the current statistical period, directly enter the next statistical period and return to step S41; otherwise, use the node identifier update value of each node as the candidate node identifier corresponding to each node, enter the next statistical period and return to step S41. S43: If the node order reordering request information obtained in step S3 is set, a node order reordering request event is triggered. This node order reordering request event compares the candidate node identifier of each node with the current node identifier. If they are the same, the current node order reordering request event is ignored; if they are different, the corresponding node enters the waiting stage until it receives the beacon signal of the next round of PLCA mechanism execution cycle, and updates the node identifier of each node in the vehicle multipoint communication network to the corresponding candidate node identifier.

8. The method of claim 7, wherein, The expression for calculating the node traffic load weight value is: In the formula, is the node traffic load weight value of the i-th node in the current statistical period, is the priority sending queue index, is the priority index maximum value of the priority sending queue, represents the weight coefficient corresponding to the priority sending queue with the priority of is the number of messages actually sent by the i-th node in the priority sending queue with the priority of in the current statistical period. is the number of messages actually sent by the i-th node in the priority sending queue with the priority of in the current statistical period. ​ 9. A multi-point network priority-aware based vehicular communication system, characterized by, It includes a memory and a processor, the memory storing a computer program, the processor invoking the computer program to perform the steps of the method as described in any one of claims 1 to 8.

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