A double-threshold value cooperation reservation based vehicle networking D2D resource allocation method

Abstract

This invention relates to the field of vehicle-to-everything (V2X) technology and discloses a method for allocating D2D (Device-to-Device) resources in V2X based on dual-threshold cooperative reservation. The method includes: a base station periodically acquiring link status information of cellular users and D2D user pairs within the V2X coverage area, and calculating the signal-to-interference-plus-noise ratio (SINR) of the D2D link; dividing the SINR into three intervals using preset handover and reservation thresholds to determine the corresponding operating modes of the D2D user pairs; constructing a weighted bipartite graph based on the operating modes and service priority weights of the D2D user pairs, and performing user-resource block matching and allocation using a weighted Hungarian algorithm, marking the resource blocks matched by users in the cooperative reservation mode as reserved; periodically monitoring the status of reserved resource blocks, and releasing the corresponding resource blocks to the available resource pool when preset release conditions are met. This invention can improve the spectrum resource utilization rate of V2X D2D communication systems under limited spectrum resource conditions.

Description

Technical Field

[0001] This invention relates to the field of vehicle networking technology, and in particular to a vehicle networking D2D resource allocation method based on dual-threshold collaborative reservation. Background Technology

[0002] With the rapid development of the intelligent connected vehicle industry, vehicle-to-everything (V2X) technology and next-generation mobile communication technology are deeply integrated, continuously improving the connectivity and intelligence of vehicles. Diverse services such as collision warning, autonomous driving collaborative decision-making, platooning, and real-time traffic interaction are emerging. These services generally have core communication requirements of high reliability, low latency, and massive connectivity, placing extremely high demands on the scheduling efficiency and service guarantee capabilities of wireless communication resources. Device-to-device (D2D) communication technology, as a core technology of next-generation cellular mobile communication systems, enables direct communication links between vehicle terminals without the need for base station relay. Compared to traditional cellular communication modes, it significantly reduces end-to-end communication latency, improves spectrum resource utilization efficiency, and enhances network edge coverage capabilities. It has become a key solution for meeting the core needs of vehicle-to-vehicle and vehicle-to-infrastructure communication in high-speed dynamic scenarios of the V2X network.

[0003] Current D2D communication resource allocation schemes in vehicle-to-everything (V2X) scenarios are mainly divided into two categories: cellular mode and multiplexing mode. In cellular mode, D2D users are allocated independent spectrum resources by the base station, isolated from the spectrum resources of cellular users. This effectively avoids co-channel interference and ensures the stability of the communication link. However, spectrum resources cannot be reused in this mode, resulting in low spectrum utilization efficiency and making it difficult to meet the needs of large-scale concurrent access scenarios in V2X. In multiplexing mode, D2D users can reuse the spectrum resources of cellular users for communication, significantly improving spectrum reuse efficiency and meeting the resource access needs of high-density vehicle scenarios. However, in this mode, mutual interference is prone to occur between D2D users and cellular users, and between adjacent D2D users. Improper resource scheduling can directly lead to deterioration of communication link quality, failing to meet the reliable transmission requirements of high-priority services.

[0004] Currently, most mainstream D2D resource allocation solutions in the vehicle-to-everything (V2X) industry employ a single signal-to-interference-plus-noise ratio (SINR) threshold to switch between two communication modes. Specifically, when the SINR of the D2D link exceeds a preset threshold, a multiplexing mode is used to improve resource utilization; when it falls below the threshold, cellular mode is switched to ensure communication reliability. However, some existing technologies rely on a fixed single threshold for mode switching and access determination, using only the current link signal quality as the sole basis for mode decision-making. This fails to fully consider the core characteristics of V2X scenarios, such as high-speed vehicle movement, drastic time-varying wireless channels, and significant differences in service quality requirements. Consequently, these solutions have numerous shortcomings that make them difficult to adapt to practical engineering applications, as detailed below.

[0005] First, the single threshold decision mechanism is rigid and cannot adapt to the dynamic channel characteristics of vehicle-to-everything (V2X) communication. A fixed single threshold cannot cope with the frequent fluctuations in channel quality in high-speed mobile scenarios, which can easily lead to frequent switching between two communication modes by D2D users. This significantly increases the signaling interaction overhead between the base station and the vehicle terminal. At the same time, frequent mode switching can easily lead to communication link interruption, reducing the stability and continuity of V2X communication.

[0006] Secondly, there is a lack of a robust mechanism for tiered protection of high-priority services, resulting in insufficient interference avoidance capabilities. Most existing solutions fail to differentiate the service quality requirements of different types of vehicle-to-everything (V2X) services. Core services such as safety and autonomous driving control are treated the same as general infotainment services, with uniform resource competition and allocation rules applied. High-priority services cannot obtain priority in resource scheduling, making them prone to transmission interruptions in intensive scenarios. Furthermore, most existing solutions only suppress co-channel interference in multiplexing modes through power control, lacking a collaborative sensing mechanism between base stations and vehicles, and between adjacent vehicles. This prevents proactive interference avoidance of reserved resources, making it difficult to effectively control resource conflicts and co-channel interference.

[0007] Third, spectrum resource utilization efficiency is low, lacking closed-loop scheduling and management throughout the entire resource lifecycle. Most existing resource allocation schemes only match resources based on basic channel capacity and interference levels, without introducing optimization mechanisms such as service priority weighting and cooperative resource reservation. This results in insufficient flexibility in resource reuse, making it difficult to maximize system capacity under limited spectrum resources. Furthermore, existing schemes lack intelligent monitoring and release mechanisms for reserved resources. Even if allocated resources experience service termination, link quality deterioration, or long-term idleness, they cannot be promptly returned to the available resource pool, leading to ineffective waste of spectrum resources and further exacerbating the spectrum resource supply and demand tension in vehicle-to-everything (V2X) scenarios. Summary of the Invention

[0008] To address the aforementioned issues, this invention proposes a vehicle-to-everything (V2D) resource allocation method based on dual-threshold cooperative reservation. This method enables refined D2D operating mode decision-making, reduces signaling overhead, and improves communication stability. It establishes a hierarchical protection and cooperative interference avoidance mechanism to ensure reliable transmission of core services and reduce resource conflicts. By introducing service priority weighting, cooperative reservation, and dynamic resource scheduling mechanisms, it optimizes resource matching logic, improves spectrum resource reuse efficiency, and enhances the spectrum resource utilization rate of the V2D communication system under limited spectrum resource conditions.

[0009] The technical solution adopted in this invention is as follows: A vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation includes: The base station periodically acquires the link status information of cellular users and D2D users within the coverage area of ​​the vehicle network, and calculates the signal-to-interference-plus-noise ratio of the D2D link, which is recorded as the SINR value. The SINR value is divided into three intervals by a preset switching threshold and a reservation threshold, which are used to determine the working mode of D2D user pairs. The working modes include cellular mode, multiplexing mode and collaborative reservation mode. A weighted bipartite graph is constructed based on the working mode and business priority weight of D2D user pairs. The weighted Hungarian algorithm is used to match and allocate users and resource blocks, and the resource blocks matched by users in the collaborative reservation mode are reserved and marked. The status of reserved resource blocks is periodically monitored, and the corresponding resource blocks are released to the available resource pool when the preset release conditions are met.

[0010] Furthermore, the base station periodically acquires link status information of cellular users and D2D user pairs within the vehicle network coverage area, and calculates the signal-to-interference-plus-noise ratio of the D2D link, including: The base station obtains the transmission power of all cellular users within its coverage area at a fixed scheduling period. Obtain the transmit power of D2D user pairs Channel gain of D2D link Interference channel gain and additive white Gaussian noise power ; Based on the acquired link state information, calculate the signal-to-interference-plus-noise ratio of the D2D link:

[0011] in, SINR is the signal-to-interference-plus-noise ratio of a D2D link.

[0012] Furthermore, the step of dividing the SINR value into three intervals using preset switching thresholds and reserved thresholds to determine the working mode of the D2D user pair includes: Two non-overlapping fixed SINR thresholds are preset: a switching threshold and a reserved threshold, wherein the value of the reserved threshold is greater than that of the switching threshold. When the SINR value of the D2D link is greater than or equal to the reservation threshold, it is determined that the D2D user is working in collaborative reservation mode. When the SINR value of the D2D link is greater than or equal to the switching threshold and less than the reserved threshold, it is determined that the D2D user is working in multiplexing mode. When the SINR value of a D2D link is less than the handover threshold, it is determined that the D2D user pair is working in cellular mode.

[0013] Furthermore, the service priority weights are set according to the D2D user's service quality requirements for the transmitted services, with different levels of services corresponding to different priority weights; among them, security services have higher priority weights than control services, and control services have higher priority weights than ordinary services.

[0014] Furthermore, the construction of a weighted bipartite graph based on the working patterns and business priority weights of D2D user pairs includes: The D2D user pairs to be allocated are divided into a collaborative reserved user set and a reuse user set, with the resource allocation priority of the collaborative reserved user set being higher than that of the reuse user set; Available resource blocks are divided into a dedicated reserved resource set and a general reuse resource set. The dedicated reserved resource set is only allocated to the collaborative reserved user set, while the general reuse resource set can be allocated to the collaborative reserved user set that has not been matched and the entire reuse user set. Using D2D user pairs as left nodes and available resource blocks as right nodes, the edge weights are calculated by combining the service priority weights of D2D user pairs, the channel capacity of the corresponding resource blocks, the resource occupancy status, and the reservation validity period, and a weighted bipartite graph is constructed. Invalid edges that cannot achieve effective matching in a weighted bipartite graph are removed, and only valid matching edges are retained.

[0015] Furthermore, the matching and allocation of users and resource blocks using the weighted Hungarian algorithm includes: The left and right vertex labels of the weighted bipartite graph are initialized. The left vertex label of the cooperative reserved user set is taken as the maximum weight of all valid edges of the user, and the left vertex label of the reused user set is taken as the maximum weight of all valid edges of the user. The right vertex labels of all resource blocks are initialized to 0. Based on the initialized top labels, construct an equal subgraph. Search for augmenting paths in the equal subgraph in descending order of priority, prioritizing the matching of the collaborative reserved user set and the dedicated reserved resource set. After all the collaborative reserved user sets have been matched, then perform the matching of the reused user set and the remaining resources of the general reused resource set. If no augmenting path is found, calculate the top label adjustment amount and dynamically adjust the top label; rebuild the equal subgraph and continue searching for augmenting paths until all matching users and resource blocks are completed.

[0016] Furthermore, the step of searching for augmenting paths in the equal subgraph in descending order of priority includes: First priority: Search the augmented path from the centralized security business users to the dedicated reserved resource set to complete the dedicated resource allocation for security business; Second priority: Search collaboration reserved users centralized control business users to the remaining resources of the dedicated reserved resource set to complete the dedicated resource allocation of control business; Third priority: Search for the augmented path from ordinary business users in the collaborative reserved user set to the remaining resources in the dedicated reserved resource set. If the dedicated reserved resource set is insufficient, search for the augmented path from it to the general reuse resource set. Fourth priority: After all users in the reserved user set for collaboration have been matched, search for an augmenting path from the reused user set to the remaining resources in the general reused resource set, and complete the resource allocation for reused users.

[0017] Furthermore, the step of reserving and marking the resource blocks matched by users in the collaborative reservation mode includes: Resource blocks matched by users in the collaborative reservation mode are marked and managed. The marking content includes the resource block number, the reserved user identifier, the reservation priority, and the reservation validity period. During the validity period, the resource block is only used by the corresponding reserved user and will not participate in the resource allocation of other users.

[0018] Furthermore, the periodic monitoring of the status of reserved resource blocks and the release of the corresponding resource blocks to the available resource pool when preset release conditions are met includes: The link status and usage of reserved resource blocks are periodically monitored using a fixed scheduling cycle. When a reserved resource block meets any preset release condition, the resource block is immediately released to the available resource pool corresponding to the general reuse resource set. The preset release conditions include: the link quality continues to deteriorate to the point that it does not meet the minimum requirements of the cellular mode; the communication service of the corresponding reserved user is terminated; the validity period of the resource block reservation expires and no renewal request is received; the system load is lower than a preset threshold and the resource block has not been used for several consecutive scheduling cycles.

[0019] Furthermore, after completing the matching and allocation of users and resource blocks, the process also includes: The base station broadcasts a cooperation awareness notification to the D2D user pair that triggered the resource reservation and to neighboring vehicles within the preset cooperation range, informing them of the relevant information of the reserved resources. Neighboring vehicles that receive a collaboration awareness notification will avoid using the reserved resource block within the reserved time window for the corresponding resource.

[0020] The beneficial effects of this invention are as follows: 1. This invention effectively solves the core problems of rigid single-threshold decision-making and frequent mode switching in existing technologies through an innovatively designed dual-threshold, three-level refined decision-making mechanism. Specifically, by using two non-overlapping signal-to-interference-plus-noise ratio thresholds, the link quality is divided into three continuous intervals, corresponding to cellular mode, multiplexing mode, and cooperative reserved mode, respectively, allowing for differentiated resource scheduling strategies to be matched for D2D communication under different channel quality conditions. This mechanism introduces a hysteresis effect in mode switching, effectively avoiding frequent mode switching caused by small fluctuations in channel quality in high-speed vehicle-to-everything (V2X) scenarios. It significantly reduces the invalid signaling overhead caused by mode switching, significantly improves the continuity of D2D communication links and the stability of system operation, and can better adapt to the dynamic characteristics of V2X channels with drastic time-varying characteristics.

[0021] 2. This invention constructs an integrated mechanism for hierarchical resource reservation and cooperative interference avoidance. Based on the service quality requirements of different vehicle-to-everything (V2X) services, it sets hierarchical priority weights, providing dedicated resource reservation guarantees for high-priority services such as safety and control. From a resource allocation architecture perspective, this ensures that high-priority services have an absolute competitive advantage in resource competition, effectively preventing core services from being preempted by ordinary services in resource contention. This significantly reduces the probability of transmission interruptions for high-priority services and fully meets the high-reliability, low-latency transmission requirements of core V2X services such as safe driving and autonomous driving collaborative control. Simultaneously, this invention, through a cooperative perception notification mechanism broadcast by the base station, enables adjacent vehicles to actively avoid reserved resources, forming a closed-loop interference control system. Compared to traditional interference suppression schemes that rely solely on power control, this more effectively reduces co-channel interference between adjacent D2D users, further improving the transmission quality and reliability of communication links on reserved resources.

[0022] 3. This invention innovatively proposes a weighted Hungarian algorithm based on collaborative reservation, which specifically optimizes and improves traditional resource matching algorithms. Through dual-partition management of users and resources, it ensures the priority allocation rights of users with collaborative reservation rights at the algorithm execution level. Simultaneously, it integrates multi-dimensional parameters such as service priority, channel capacity, resource occupancy status, and reservation validity period in edge weight calculation. Combined with hierarchical augmenting path search and dynamic top-index adjustment mechanisms, it achieves the optimal solution for overall system resource matching while ensuring the resource needs of high-priority services, effectively improving the overall communication capacity of the system. Furthermore, this invention designs multiple composite release conditions and a periodic monitoring mechanism to achieve closed-loop management of reserved resources throughout their entire lifecycle. It can promptly reclaim reserved resources due to link deterioration, service termination, expiration, or long-term idleness, avoiding the ineffective occupation of spectrum resources. While ensuring dedicated resources for high-priority services, it significantly improves the overall utilization efficiency of spectrum resources and can better adapt to the concurrent access needs of large-scale terminals in high-density vehicle scenarios.

[0023] 4. This invention constructs a refined resource scheduling system covering the entire process of decision-making, reservation, allocation, and release. The various technical links are interconnected and work together. Without adding extra hardware equipment or increasing the deployment costs of vehicle terminals and base stations, it has completed a comprehensive optimization of the existing D2D resource allocation scheme for vehicle-to-everything (V2X) networks. It can adapt to the complex scenario characteristics of high-speed mobility and time-varying channels in V2X networks, and can also take into account the efficiency of spectrum resource utilization and the transmission reliability of core services. It has strong engineering feasibility and promotional application value. Attached Figure Description

[0024] Figure 1 This is a flowchart of a vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation, according to Embodiment 2 of the present invention.

[0025] Figure 2 This is a link model diagram of the vehicle-to-everything (V2D) communication system according to Embodiment 3 of the present invention.

[0026] Figure 3 This is a flowchart of the resource allocation process of the Hungarian algorithm based on collaborative reservation weighting in Embodiment 3 of the present invention.

[0027] Figure 4 This is a comparison chart of system spectrum resource utilization under different vehicle densities in Embodiment 3 of the present invention.

[0028] Figure 5 This is a comparison chart of the probability of interruption of high-priority services (security category) as a function of vehicle speed in Embodiment 3 of the present invention.

[0029] Figure 6 This is a comparison chart of the average number of mode switching times as a function of the scheduling cycle in Embodiment 3 of the present invention. Detailed Implementation

[0030] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments are now described. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of the invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0031] Example 1 like Figure 1 As shown, this embodiment provides a vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation, including... The base station periodically acquires the link status information of cellular users and D2D users within the coverage area of ​​the vehicle network, and calculates the signal-to-interference-plus-noise ratio of the D2D link, which is recorded as the SINR value. The SINR value is divided into three intervals by a preset switching threshold and a reservation threshold, which are used to determine the working mode of D2D user pairs. The working modes include cellular mode, multiplexing mode and collaborative reservation mode. A weighted bipartite graph is constructed based on the working mode and business priority weight of D2D user pairs. The weighted Hungarian algorithm is used to match and allocate users and resource blocks, and the resource blocks matched by users in the collaborative reservation mode are reserved and marked. The status of reserved resource blocks is periodically monitored, and the corresponding resource blocks are released to the available resource pool when the preset release conditions are met.

[0032] Preferably, the base station acquires the transmission power of all cellular users within its coverage area at a fixed scheduling period. Obtain the transmit power of D2D user pairs Channel gain of D2D link Interference channel gain and additive white Gaussian noise power Based on the acquired link state information, calculate the signal-to-interference-plus-noise ratio of the D2D link:

[0033] in, SINR is the signal-to-interference-plus-noise ratio of a D2D link.

[0034] Specifically, the vehicle-mounted terminal reports its own transmit power, link channel measurement results, and other information to the base station through the uplink control channel according to the scheduling cycle agreed upon with the base station. Cellular users simultaneously report their own transmit power parameters to the base station. At the beginning of each scheduling cycle, the base station completes the collection and verification of all link status information. After removing abnormal and invalid reported data, it calculates the SINR value of the D2D link pair one by one based on the collected valid parameters, generating the corresponding SINR calculation result for each D2D user pair.

[0035] It should be noted that this step, through periodic collection of link state information and standardized SINR calculation, can accurately capture the time-varying characteristics of the channel in high-speed mobile scenarios of vehicle-to-everything (V2X) networks. This provides accurate and real-time quantitative basis for subsequent mode determination and resource allocation, avoiding resource allocation mismatch caused by channel information lag.

[0036] Preferably, two non-overlapping fixed SINR thresholds are preset, namely a handover threshold and a reservation threshold, wherein the value of the reservation threshold is greater than the handover threshold; when the SINR value of the D2D link is greater than or equal to the reservation threshold, the D2D user pair is determined to be working in cooperative reservation mode; when the SINR value of the D2D link is greater than or equal to the handover threshold and less than the reservation threshold, the D2D user pair is determined to be working in multiplexing mode; when the SINR value of the D2D link is less than the handover threshold, the D2D user pair is determined to be working in cellular mode.

[0037] Specifically, the base station pre-configures and stores two non-overlapping SINR thresholds. After calculating the SINR value for each D2D user pair, it compares the calculation result with the two preset thresholds to determine the corresponding working mode. For D2D user pairs determined to be in cellular mode, the base station directly allocates independent dedicated spectrum resources to them, without participating in the subsequent resource reuse and reservation process. For D2D user pairs determined to be in reuse mode and cooperative reservation mode, they enter the subsequent weighted bipartite graph construction and resource matching process.

[0038] It should be noted that this step replaces the traditional single-threshold switching scheme with a dual-threshold, three-level decision-making mode division mechanism. This effectively avoids the problem of frequent mode switching caused by small channel fluctuations, significantly reduces the signaling overhead caused by mode switching, and significantly improves the stability of D2D communication in high-speed dynamic scenarios of vehicle networking.

[0039] Preferably, the service priority weight is set according to the service quality requirements of D2D users for the transmitted services, and different levels of services correspond to different priority weights; among them, the priority weight of security services is higher than that of control services, and the priority weight of control services is higher than that of ordinary services.

[0040] Specifically, the base station pre-configures the service priority classification and corresponding weights based on the service quality requirements of various vehicle-to-everything (V2X) services. While reporting link status information, the vehicle terminal simultaneously reports the type identifier of the service to be transmitted to the base station. After receiving the service type identifier, the base station matches the pre-set priority weights for the corresponding D2D users and incorporates the weight parameters into the subsequent resource matching calculation process.

[0041] It should be noted that by setting hierarchical weights based on service quality requirements, differentiated resource competitive advantages can be provided for core services in the Internet of Vehicles (IoV) that require high reliability and low latency, such as safety and control services. This avoids transmission interruptions caused by high-priority services failing to compete for resources, and achieves hierarchical service quality assurance for IoV services.

[0042] Preferably, the step of constructing a weighted bipartite graph based on the working mode and business priority weight of D2D user pairs includes: The D2D user pairs to be allocated are divided into a collaborative reserved user set and a reuse user set, with the resource allocation priority of the collaborative reserved user set being higher than that of the reuse user set; Available resource blocks are divided into a dedicated reserved resource set and a general reuse resource set. The dedicated reserved resource set is only allocated to the collaborative reserved user set, while the general reuse resource set can be allocated to the collaborative reserved user set that has not been matched and the entire reuse user set. Using D2D user pairs as left nodes and available resource blocks as right nodes, the edge weights are calculated by combining the service priority weights of D2D user pairs, the channel capacity of the corresponding resource blocks, the resource occupancy status, and the reservation validity period, and a weighted bipartite graph is constructed. Invalid edges that cannot achieve effective matching in a weighted bipartite graph are removed, and only valid matching edges are retained.

[0043] Specifically, based on the mode decision results, the base station classifies and aggregates the users to be allocated. D2D user pairs determined to be in the cooperative reservation mode are assigned to the cooperative reservation user set, and D2D user pairs determined to be in the reuse mode are assigned to the reuse user set. At the same time, the available spectrum resource blocks in the current scheduling period are partitioned and managed, dividing them into a dedicated reserved resource set open only to cooperative reservation users and a general reuse resource set open to all users to be allocated. Then, with users as left nodes and resource blocks as right nodes, multi-dimensional parameters are integrated to complete edge weight calculation, construct a weighted bipartite graph, and remove invalid edges that cannot achieve effective matching, such as resources that have been occupied, reserved expired, or communication quality that does not meet the standards, thus completing the optimization processing of the bipartite graph.

[0044] It should be noted that this step, through dual-partition management of users and resources, ensures priority allocation permissions for users reserved for collaboration from an architectural perspective. At the same time, through edge weight calculation and invalid edge removal by multi-dimensional parameter fusion, it can achieve fine-grained control of resource matching, significantly reduce the calculation scope of subsequent algorithms, improve the execution efficiency of resource allocation, and adapt to the low-latency scheduling requirements of vehicle networking scenarios.

[0045] Preferably, the step of matching and allocating users and resource blocks using the weighted Hungarian algorithm includes: The left and right vertex labels of the weighted bipartite graph are initialized. The left vertex label of the cooperative reserved user set is taken as the maximum weight of all valid edges of the user, and the left vertex label of the reused user set is taken as the maximum weight of all valid edges of the user. The right vertex labels of all resource blocks are initialized to 0. Based on the initialized top labels, construct an equal subgraph. Search for augmenting paths in the equal subgraph in descending order of priority, prioritizing the matching of the collaborative reserved user set and the dedicated reserved resource set. After all the collaborative reserved user sets have been matched, then perform the matching of the reused user set and the remaining resources of the general reused resource set. If no augmenting path is found, calculate the top label adjustment amount and dynamically adjust the top label; rebuild the equal subgraph and continue searching for augmenting paths until all matching users and resource blocks are completed.

[0046] Specifically, after constructing the weighted bipartite graph, the base station first initializes the left and right top labels of the bipartite graph to ensure that the initialized top labels meet the preset constraints. Then, it constructs an equal subgraph based on the initialized top labels, retaining only the valid edges that meet the top label constraints. Next, it performs augmenting path search according to the preset priority order, prioritizing resource matching for cooperative reserved users. After all cooperative reserved users have been matched, it then performs resource matching for reused users. If no valid augmenting path is found in the current equal subgraph, the corresponding top label adjustment amount is calculated. After the top labels are dynamically updated, the equal subgraph is reconstructed and the augmenting path search continues until the resource allocation for all matching users is completed.

[0047] It should be noted that this step optimizes and improves the traditional Hungarian algorithm by adapting the top-level initialization, equal subgraph construction and dynamic adjustment process of the collaborative reservation mechanism. While ensuring that collaborative reservation users are given priority in allocating permissions, it achieves the optimal solution for overall system resource matching, and can maximize the overall capacity of the vehicle-to-everything (V2D) communication system under limited spectrum resources.

[0048] Preferably, the step of searching for augmenting paths in the equal subgraph in descending order of priority includes: First priority: Search the augmented path from the centralized security business users to the dedicated reserved resource set to complete the dedicated resource allocation for security business; Second priority: Search collaboration reserved users centralized control business users to the remaining resources of the dedicated reserved resource set to complete the dedicated resource allocation of control business; Third priority: Search for the augmented path from ordinary business users in the collaborative reserved user set to the remaining resources in the dedicated reserved resource set. If the dedicated reserved resource set is insufficient, search for the augmented path from it to the general reuse resource set. Fourth priority: After all users in the reserved user set for collaboration have been matched, search for an augmenting path from the reused user set to the remaining resources in the general reused resource set, and complete the resource allocation for reused users.

[0049] Specifically, during augmentation path search, the base station strictly follows a preset four-level priority order. First, it matches security service users with dedicated reserved resource sets to ensure the resource requirements of the highest priority services. Next, it matches control service users with the remaining resources in the dedicated reserved resource set to ensure the transmission requirements of core control services. Then, it matches resources for ordinary service users in the cooperative reserved user set, prioritizing dedicated resources when they are sufficient and matching general reused resources when resources are insufficient. Finally, after all cooperative reserved users have been matched, it matches reused users with the remaining resources in the general reused resource set.

[0050] It should be noted that this step, through a hierarchical augmenting path search mechanism, deeply binds service priority with resource allocation order, completely eliminating the problem of low-priority users preempting high-priority service resources from the algorithm execution level. This further enhances the transmission reliability of high-priority security services in the Internet of Vehicles and significantly reduces the probability of core service interruptions.

[0051] Preferably, the resource blocks matched by users in the collaborative reservation mode are marked and managed. The marking content includes the resource block number, the reserved user identifier, the reservation priority, and the reservation validity period. During the mark validity period, the resource block is only used by the corresponding reserved user and does not participate in the resource allocation of other users.

[0052] Specifically, after completing resource matching and allocation, the base station marks all resource blocks matched by users in the cooperative reservation mode with a unique identifier, and synchronously stores the reserved user information, priority information, and validity period information corresponding to the resource block into the base station's resource management database. During the reservation validity period corresponding to the identifier, when the base station carries out subsequent resource scheduling, it excludes the resource block from the scope of general allocable resources and only allows the corresponding reserved user to use the resource block for data transmission.

[0053] It should be noted that this step, through the exclusive marking and closed-loop management of reserved resources, can ensure the exclusive right to use the reserved resources for collaboration, avoid resource conflicts in the process of resource reuse, provide stable and continuous spectrum resource guarantee for high-priority services, and further improve the transmission stability of D2D communication links.

[0054] Preferably, the link status and usage of reserved resource blocks are periodically monitored using a fixed scheduling cycle; when a reserved resource block meets any preset release condition, the resource block is immediately released to the available resource pool corresponding to the general reuse resource set. More preferably, the preset release conditions include: The link quality continued to deteriorate to the point that it no longer met the minimum requirements for cellular mode; The communication services for the corresponding reserved users will be terminated. The resource block reservation period has expired and no renewal request has been received; The system load is below the preset threshold and the resource block has not been used for several consecutive scheduling cycles.

[0055] Specifically, during each scheduling cycle, the base station performs full status monitoring on all reserved resource blocks in the marked state, and synchronously collects information such as link quality, service transmission status, reservation validity period, and resource usage corresponding to the resource blocks. The collected status information is compared with the preset release conditions one by one. When a resource block meets any release condition, the reservation mark of the resource block is immediately cleared and it is released to the available resource pool of the general reuse resource set to participate in the resource allocation of subsequent scheduling cycles.

[0056] It should be noted that this step, through the setting of multiple composite release conditions and periodic monitoring mechanisms, can release idle and invalid reserved resources in a timely manner, avoiding the ineffective occupation of spectrum resources. While ensuring the resource needs of high-priority services, it significantly improves the overall utilization efficiency of spectrum resources and achieves a dynamic balance between resource reservation and resource utilization.

[0057] Preferably, after completing the matching and allocation of users and resource blocks, the method further includes: the base station broadcasts a cooperation awareness notification to the D2D user pair that triggered the resource reservation and the adjacent vehicles within the preset cooperation range, informing them of the relevant information of the reserved resources; the adjacent vehicles that receive the cooperation awareness notification avoid using the reserved resource block within the reservation time window of the corresponding resource.

[0058] Specifically, after the allocation and marking of reserved resources are completed, the base station sends a cooperation awareness notification to the D2D user pairs that have completed resource reservation and all adjacent vehicle terminals within the preset cooperation range through the broadcast channel. The notification content includes core information such as the number of the reserved resource block and the reservation time window. The adjacent vehicle terminals that receive the notification actively avoid using the reserved resource block within the corresponding reservation time window and do not initiate data transmission on the resource block.

[0059] It should be noted that this step constructs a distributed interference avoidance system among vehicles through the collaborative perception notification mechanism broadcast by the base station. This effectively reduces co-channel interference between adjacent vehicles and reserved resource blocks, further improving the transmission quality of the D2D communication link on the reserved resources and ensuring the high reliability transmission requirements of high-priority services.

[0060] Example 2 This embodiment provides a vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation, referencing... Figure 1 This includes the following steps: Step S1: The base station acquires link status and vehicle movement information. The base station periodically acquires the link status information of all cellular users (C-UE) and D2D user pairs (D-UE pair) within its coverage area at a fixed scheduling period T. All information is reported wirelessly by the vehicle terminal to meet real-time requirements.

[0061] Specifically, the link state information includes D2D user transmit power. Cellular user transmit power D2D link channel gain Interference channel gain and additive white Gaussian noise power .

[0062] Step S2: Current SINR Calculation Based on the acquired link state information, the base station calculates the current D2D link SINR (signal-to-interference-plus-noise ratio) to provide an accurate basis for subsequent mode decision-making. The core formula is as follows:

[0063] in, This refers to the SINR value of the D2D link.

[0064] Step S3: Determine the D2D working mode using dual threshold decision. This embodiment innovatively sets two non-overlapping fixed SINR thresholds—the switching threshold. and reserved threshold ( ), will change the current SINR value Divided into three intervals, this achieves three levels of refined decision-making in the D2D working mode: 1. If The D2D link is determined to be in cooperative reserved mode. This D2D link has excellent channel quality and low interference, providing dedicated resource reservation for high-priority services. 2. If The system is determined to be in reuse mode. The link quality meets the reuse requirements, and the spectrum resources of cellular users are reused to improve resource utilization. 3. If The signal is determined to be in cellular mode, with poor link quality and high interference. Independent spectrum resources will be allocated to the base station to avoid interference.

[0065] Step S4: Generating Tiered Resource Reservation Requests in Collaborative Reservation Mode If a D2D user pair is determined to be in cooperative reservation mode, the base station generates a tiered resource reservation request based on its service type, introducing service priority weights. To ensure that high-priority services receive resources first, the reserved request includes the user identifier, the number of resources requested, and the reserved priority. and reserved validity period .

[0066] Priority reservations are set according to the QoS requirements of connected vehicle services: security-related services have the highest priority. Control-related businesses are the second most important. Ordinary business has the lowest priority. ),and .

[0067] Step S5: Implement resource allocation based on the cooperative reservation weighted Hungarian algorithm The base station collects all users to be allocated and the set of available resource blocks, and performs mathematical modeling of the resource allocation problem.

[0068] Preferably, step S5 includes the following sub-steps: Sub-step 5.1: Data preprocessing and bipartite graph construction 1. User partitioning: Dividing the set of users to be assigned... Divided into two categories, namely ,in Reserve a user set for collaboration (to satisfy) ), For reusing user sets (satisfying) ),clear Resource allocation priority is higher than This ensures that users who reserve space for collaboration have priority in allocation.

[0069] 2. Resource partitioning: Dividing the available resource blocks into sets. Divided into two categories, namely ,in This is a dedicated reserved resource set, allocated only to collaborative reserved user sets. User reuse is prohibited Occupy; It is a general-purpose reusable resource set that can be flexibly allocated. Users who did not complete the matching All users.

[0070] 3. Edge weight calculation: Constructing a weighted bipartite graph ,in Let the set of edges have the following weights: Used to characterize the The user and the first The matching priority of each resource block is calculated by integrating three core attributes: channel quality, resource occupancy status, and reservation validity period. ,in: : The reservation priority weight for the i-th user (using the hierarchical weight from step S4, assuming security class) Control class Ordinary users and reused users ).

[0071] Channel capacity. Specifically, , For single resource block bandwidth, For the first The user used the number The SINR value of each resource block characterizes the channel transmission capability.

[0072] (Cooperation avoidance factor, used to avoid resource conflicts).

[0073] (Reservation validity period factor, used to screen valid reserved resources).

[0074] 4. Invalid Edge Removal: To improve algorithm efficiency, edges that cannot achieve a valid match are removed. Specifically, invalid edges are deleted... (Resources are already in use) (Resource reservation expired) Three types of invalid edges (due to substandard communication quality) are identified, and only valid matching edges are retained for subsequent bipartite graph construction.

[0075] Sub-step 5.2: Top label initialization (enhancing reserved priority) The top label is the core of the Hungarian algorithm, used to determine the weight benchmark for the optimal matching in the bipartite graph. In this initialization, priority is given to ensuring the matching advantage of users reserved for collaboration, and the specific rules are as follows: 1. Left superscript Collaborative Reserved User Set Take the maximum weight of all valid edges for this user. Reuse user sets Take the maximum weight of all valid edges of the given element; 2. Right top mark All resource blocks ( and All are initialized to 0; 3. Constraints: After initialization, the following conditions must be met. This ensures the effectiveness of subsequent equal subgraph construction.

[0076] Sub-step 5.3: Construction of the Equal Subgraph Only retain those that meet the requirements. Valid edges are used to construct an equal subgraph, and priority is given to retaining them. The dedicated edge for (collaborative reserved users → dedicated reserved resources) narrows the matching range and improves allocation efficiency.

[0077] Sub-step 5.4: Hierarchical augmenting path search (core collaboration reserved constraints) Augmentation paths are searched strictly according to priority order to ensure that reserved users are matched first and to prevent reserved resources from being preempted. The specific order is as follows: 1. First priority: Search Security-related users ( )arrive The Zengguang Road (with dedicated reserved resources) will be used to complete the dedicated resource allocation for security-related businesses; 2. Second priority: Search Control users ( )arrive The remaining resources are used to expand the path and complete the dedicated resource allocation for control-related businesses; 3. Third priority: Search Ordinary users ( )arrive The augmentation path for remaining resources, if Resources are insufficient; search for it. The augmentation path (for general resources) is marked as temporary reserved; 4. Fourth Priority: Pending After all users have been matched, then search. (Reuse user) to The augmentation path for remaining resources completes the allocation of reused user resources.

[0078] Sub-step 5.5: Dynamic adjustment of top label (without weakening reserved priority) When no augmentation path is found, calculate the top label adjustment amount. (Applicable only to unmatched users and resource blocks), the rules are adjusted as follows to ensure that the matching advantage of reserved users for collaboration is not diminished: 1. Unmatched collaboration reserved users ( ): left superscript ; 2. Unmatched resource blocks ( and ): Right superscript ; 3. After adjustment, return to sub-step 5.3, rebuild the equal subgraph, and continue searching for augmenting paths until all collaborative reserved users are reached. Matching complete.

[0079] Sub-step 5.6: Optimal matching output and reserved resource marking 1. After matching is complete, output the optimal matching result for the end user and resource block, ensuring... All (reserved users for collaboration) have been matched. (Reusing users) achieves optimal allocation; 2. Regarding The matched resource blocks are marked and managed, and the marking content includes: resource block number, reserved user ID, and reserved priority. Validity period reserved During the marking period, the resource block is only used by the corresponding reserved user and is not allocated to other users.

[0080] Step S6: Collaborative awareness notification enables interference avoidance After resource allocation is completed, the base station broadcasts a cooperation awareness notification to the D2D user pairs that triggered the reservation and to neighboring vehicles within the preset cooperation range, informing them of the reserved resource information. Upon receiving the notification, neighboring vehicles actively avoid using the reserved resource block within the reserved time window, establishing a vehicle-to-vehicle cooperation awareness interference avoidance mechanism to effectively reduce interference caused by resource conflicts.

[0081] Step S7: Periodic monitoring and intelligent release of reserved resources The base station periodically monitors the link status of reserved resource blocks in scheduling cycles T. It innovatively designs multiple composite release conditions; when any one condition is met, the resource block is immediately released (and then re-enters the available resource pool). This avoids wasting reserved resources. Preferably, the release conditions include: 1. Link quality continues to deteriorate: for two consecutive scheduling cycles. ; 2. Termination of communication service: The vehicle terminal sends a service termination signal to the base station; 3. Reserved validity period expired: Reserved resources... The contract expired, and no renewal request was received. 4. System load is too low and resources are idle for a long time: The system load is lower than the preset threshold and the reserved resources have not been used for three consecutive scheduling cycles.

[0082] Example 3 This embodiment provides a vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation, which is applied to the V2D highway communication scenario. The specific details are as follows.

[0083] I. System Model and Initialization Parameters This embodiment is designed for high-speed dynamic scenarios of vehicle-to-everything (V2X) communication on highways. The link model of the V2X D2D communication system is as follows: Figure 2 As shown: The base station is deployed beside the highway, with a coverage radius of 500m. The coverage area includes two one-way lanes. Vehicles travel at a constant speed along the highway, ranging from 60 to 120 km / h, and their direction of travel is consistent with the road baseline within the base station's coverage area (direction angle θ is 0° to 10°). The system adopts a centralized base station scheduling architecture, including one macro base station, several cellular users (C-UEs, mainly roadside facility terminals and vehicle-mounted non-D2D communication terminals), and several D2D user pairs (D-UE1 and D-UE2, mainly adjacent vehicle terminals; each D2D user pair corresponds to a set of vehicle-to-vehicle communication services). D2D user pairs can be configured based on dual thresholds. , Based on the judgment, cellular mode, multiplexing mode or cooperative reserved mode can be flexibly selected for communication to ensure communication quality under different channel conditions.

[0084] To ensure the repeatability and practicality of the implementation process, the core parameters of the system initialization conform to the mainstream application standards of C-V2X vehicle networking. The core parameter settings are as follows: 1. Scheduling-related parameters: Scheduling period (Meets the low-latency requirements of connected vehicle services, ensuring real-time resource scheduling); Validity period reserved. (Balancing the stability and utilization of reserved resources, avoiding frequent renewals due to excessively short validity periods and idleness due to excessively long validity periods).

[0085] 2. Link and Power Parameters: Maximum Transmit Power for D2D Users Maximum transmit power for cellular users All meet the power standards for vehicle networking terminals; additive white Gaussian noise power. A fixed value, reflecting the actual noise characteristics of wireless channels; path loss factor. (Adapted to the fusion characteristics of large-scale and small-scale fading in V2V communication for vehicle-to-everything (V2V) networks).

[0086] 3. Dual threshold parameters: switch thresholds (The minimum threshold to ensure link communication quality; communication reliability cannot be guaranteed below this threshold); Reserved threshold (A threshold for determining excellent channel quality; when the quality is above this threshold, stable transmission of high-priority services can be guaranteed.)

[0087] 4. Collaboration Parameters: Collaboration Perception Range (Covering the communication range of adjacent vehicles to ensure the effectiveness of interference avoidance).

[0088] 5. Priority weighting parameter: Priority weighting for security-related services. Priority weight of control-related business Priority weight of general business In reuse mode, user priority weights are unified as follows: (Ensure that high-priority services receive priority in resource allocation).

[0089] II. Specific Implementation Steps This embodiment takes a D2D user pair (D-UE pair, ID D001) of a security service (collision warning) as an example to illustrate the complete implementation process of this method.

[0090] Step 1: Information Collection The base station periodically collects link status information and vehicle movement information of all C-UE and D-UE pairs within its coverage area, with a scheduling period of T=100 ms. Figure 2 The system link model is shown. The link status information includes the transmit power of D001. Transmit power of surrounding C-UEs D2D link channel gain of D001 C-UE interference channel gain for D001 and additive white Gaussian noise power Vehicle motion information includes the current positions of the two vehicles corresponding to D001, their speed v = 80 km / h, and their direction angle θ = 5°. All information is periodically reported by the vehicle-mounted terminal via a wireless link, with a reporting latency of ≤10ms, ensuring that the base station obtains the latest status in real time.

[0091] Step 2: SINR Calculation The base station analyzes and processes the collected information, and calculates the D2D link SINR value γ of D001 at the current time according to the following formula:

[0092] The calculated value of γ = 12 dB indicates that the current link quality is excellent, providing a basis for subsequent mode decision-making.

[0093] Step 3: Dual Threshold Mode Decision The base station will compare the current SINR value γ=12dB with the dual threshold. =3dB =10dB for comparison, since γ≥ D001 is determined to be in collaborative reservation mode, which meets the conditions for high-priority business resource reservation, and will proceed to the subsequent hierarchical reservation process.

[0094] Step 4: Generation of Tiered Reservation Requests The D001 service type is collision warning (security service). The base station generates a first-priority resource reservation request for it, containing the following unique identifier information: D2D user pair ID=D001, number of requested resource blocks=2 (to meet the bandwidth requirements of the collision warning service), and reservation priority weight. =1.5, Reserved validity period =500ms. After a reserved request is generated, it is stored in the reserved resource request queue and processed with priority.

[0095] Step 5: Collaborative Reserved Weighted Hungarian Algorithm Resource Allocation The base station collects all currently unassigned users (10 groups of users in cooperative reservation mode, including D001; 20 groups of users in reuse mode, totaling 30), and calculates that there are currently 40 available resource blocks, which meets the needs of all users. Subsequently, resource allocation is performed according to the core process of the cooperative reservation weighted Hungarian algorithm, referencing... Figure 3 The specific sub-steps are as follows: Sub-step 5.1: Data preprocessing and bipartite graph construction—divide the users to be assigned into a collaborative reserved user set U1 (10 groups, including D001) and a reuse user set U2 (20 groups); divide the available resource blocks into a dedicated reserved resource set V1 and a general reuse resource set V2; calculate edge weights. ω of D001 i =1.5, By Shannon's formula Calculations show that =1 (Resource block not avoided by collaboration). =1 (Resource block is within the reservation validity period); Remove =0、 For invalid edges with a value of 0, construct an effective weighted bipartite graph.

[0096] Sub-step 5.2: Top-level initialization—The left top-level index l(u) of the collaborative reserved user set U1 is taken as the maximum weight of all valid edges of its own set, and the left top-level index l(u) of the reused user set U2 is taken as the maximum weight of its own valid edges; the right top-level index r(v) of all resource blocks is initialized to 0, ensuring that l(u) + r(v) ≥ .

[0097] Sub-step 5.3: Construction of equal subgraphs – retain only those satisfying l(u) + r(v) = For valid edges, prioritize retaining the exclusive edge from U1 to V1 to construct an equal subgraph.

[0098] Sub-step 5.4: Hierarchical augmentation path search—First, search for augmentation paths from security users (including D001) in U1 to V1. D001 is preferentially matched with two dedicated reserved resource blocks (numbered RB10 and RB11) with the best channel capacity. Then, search for augmentation paths from control users and ordinary users in U1 to the remaining resources in V1. Finally, search for augmentation paths from U2 to the remaining resources in V2 to complete the matching of all users.

[0099] Sub-step 5.5: Top Label Adjustment (if needed) – Since all collaborative reserved users have found augmenting paths, no top label adjustment is needed; if no augmenting path has been found, calculate the adjustment amount. Adjust the top labels of unmatched users and resource blocks, reconstruct the equal subgraph and search for augmenting paths until all U1 is matched.

[0100] Sub-step 5.6: Matching Result Output and Marking – Output the user-resource block matching result. D001 matches resource blocks RB10 and RB11. The base station marks these two resource blocks in the reserved resource management table. The marking content includes: resource block number, reserved user ID (D001), reserved priority ω1=1.5, and reserved validity period. =500ms, during which the resource block is used only by D001.

[0101] Step 6: Collaborative Perception and Interference Avoidance After resource allocation is completed, the base station broadcasts a cooperation awareness notification to vehicle D001 and 15 adjacent vehicles within a cooperation range of R=200 m. The core information includes: reserved resource block numbers (RB10, RB11), reserved time window [0 ms, 500 ms], and reserved D2D user pair ID (D001). Upon receiving the notification, adjacent vehicles update their local resource usage lists and actively avoid using these two resource blocks within the reserved time window to prevent interference with the collision warning service.

[0102] Step 7: Reserved Resources Monitoring and Release The base station periodically monitors the status of link D001 and the usage of resource blocks RB10 and RB11, with a scheduling period of T=100 ms. In the first three scheduling cycles (0~300 ms), the SINR values ​​of D001 were 12.5dB, 12dB, and 11.8dB, respectively, all ≥ γ2=10dB, indicating that the link status was stable and resource release was not triggered. In the fourth scheduling cycle (300~400 ms), the D001 collision warning service is completed. The vehicle terminal sends a service termination signal to the base station. The base station triggers the resource release condition, deletes the markers of RB10 and RB11 in the reserved resource management table, and re-includes them in the available resource pool V2 for subsequent user allocation.

[0103] like Figure 4 The diagram shows a comparison of system spectrum resource utilization under different vehicle densities. Specifically, it compares the spectrum resource utilization performance of the traditional single-threshold + Hungarian algorithm and the resource allocation algorithm of this invention under different vehicle densities in a vehicle-to-everything (D2D) communication scenario. The core calculation formula is η=C. total / B total The total weighted capacity of the system, C total The total available bandwidth B is calculated by weighting factors such as service priority, interference avoidance factor, and reservation validity period. total This is the product of the total number of resource blocks and the bandwidth of a single block. It can be seen that as the vehicle density increases from 20 to 100 vehicles, the spectrum utilization of both algorithms shows an upward trend—this is because increased vehicle density brings more opportunities for spectrum reuse, thus improving the overall resource utilization efficiency of the system. However, at all density points, the spectrum utilization of the algorithm in this invention is higher than that of the traditional algorithm, and the performance gap between the two gradually widens as the vehicle density increases. This indicates that the algorithm in this invention can complete spectrum resource allocation more efficiently, reduce resource waste, and has significant advantages over traditional solutions, especially in complex vehicle-to-everything (V2X) scenarios with high vehicle density, where its performance improvement is even more pronounced.

[0104] like Figure 5 The diagram shows a comparison of the interruption probability of high-priority services (security-related) as a function of vehicle speed, specifically comparing the service continuity assurance capabilities of the traditional single-threshold method and the method of this invention. The interruption probability of both methods increases with vehicle speed, but the interruption probability of the traditional single-threshold method increases exponentially (rapidly from 3.5% to 23%), while the interruption probability of the method of this invention increases very slowly (from 2.0% to 5.2%). The performance gap between the two methods widens significantly with increasing vehicle speed. This trend indicates that the method of this invention can effectively suppress the impact of rapid channel changes on high-priority services in high-speed vehicle scenarios, significantly reducing the service interruption probability and significantly improving the robustness and service continuity assurance capabilities of the vehicle-to-everything (V2X) communication system in high-speed mobile environments.

[0105] like Figure 6The figure shows a comparison of the average number of mode switching times as the scheduling period changes, specifically comparing the mode switching performance of the traditional single-threshold method and the dual-threshold method of this invention. The number of mode switching times for both methods decreases with increasing scheduling period: the number of switching times for the traditional single-threshold method decreases from 180 to 55, while the number of switching times for the dual-threshold method of this invention decreases from 65 to 18. Under all scheduling periods, the number of switching times for the method of this invention is significantly lower than that for the traditional method, with a reduction of up to 63.9% (at a scheduling period of 50ms), and the overall curve is smoother. This result indicates that the dual-threshold scheduling mechanism of this invention can effectively reduce the number of mode switching times in D2D communication, reduce the signaling overhead and system burden caused by frequent switching, improve the stability of the communication link, and maintain significant advantages under different scheduling periods, thus optimizing the overall operating efficiency of the system.

[0106] Example 4 This embodiment provides a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation as described in Embodiment 1 or Embodiment 2. The computer program can be in the form of source code, object code, executable file, or some intermediate form.

[0107] Example 5 This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the vehicle-to-everything (V2D) resource allocation method based on dual-threshold cooperative reservation as described in Embodiment 1 or Embodiment 2. The computer program can be in the form of source code, object code, executable file, or some intermediate form. The storage medium includes any entity or device capable of carrying computer program code, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0108] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

[0109] It should be noted that, for the sake of simplicity, the foregoing method embodiments are described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

Claims

1. A method for D2D resource allocation based on dual-threshold cooperative reservation, characterized in that, include: The base station periodically acquires the link status information of cellular users and D2D users within the coverage area of ​​the vehicle network, and calculates the signal-to-interference-plus-noise ratio of the D2D link, which is recorded as the SINR value. The SINR value is divided into three intervals by a preset switching threshold and a reservation threshold, which are used to determine the working mode of D2D user pairs. The working modes include cellular mode, multiplexing mode and collaborative reservation mode. A weighted bipartite graph is constructed based on the working mode and business priority weight of D2D user pairs. The weighted Hungarian algorithm is used to match and allocate users and resource blocks, and the resource blocks matched by users in the collaborative reservation mode are reserved and marked. The status of reserved resource blocks is periodically monitored, and the corresponding resource blocks are released to the available resource pool when the preset release conditions are met.

2. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, The base station periodically acquires link status information of cellular users and D2D users within the vehicle network coverage area, and calculates the signal-to-interference-plus-noise ratio of the D2D link, including: The base station obtains the transmission power of all cellular users within its coverage area at a fixed scheduling period. Obtain the transmit power of D2D user pairs Channel gain of D2D link Interference channel gain and additive white Gaussian noise power ; Based on the acquired link state information, calculate the signal-to-interference-plus-noise ratio of the D2D link: in, SINR is the signal-to-interference-plus-noise ratio of a D2D link.

3. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, The process of dividing the SINR value into three intervals using preset switching thresholds and reserved thresholds to determine the working mode of D2D user pairs includes: Two non-overlapping fixed SINR thresholds are preset: a switching threshold and a reserved threshold, wherein the value of the reserved threshold is greater than that of the switching threshold. When the SINR value of the D2D link is greater than or equal to the reservation threshold, it is determined that the D2D user is working in collaborative reservation mode. When the SINR value of the D2D link is greater than or equal to the switching threshold and less than the reserved threshold, it is determined that the D2D user is working in multiplexing mode. When the SINR value of a D2D link is less than the handover threshold, it is determined that the D2D user pair is working in cellular mode.

4. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, The service priority weights are set according to the service quality requirements of D2D users for the transmitted services, and different levels of services correspond to different priority weights; among them, security services have higher priority weights than control services, and control services have higher priority weights than ordinary services.

5. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, The construction of a weighted bipartite graph based on the working modes and business priority weights of D2D user pairs includes: The D2D user pairs to be allocated are divided into a collaborative reserved user set and a reuse user set, with the resource allocation priority of the collaborative reserved user set being higher than that of the reuse user set; Available resource blocks are divided into a dedicated reserved resource set and a general reuse resource set. The dedicated reserved resource set is only allocated to the collaborative reserved user set, while the general reuse resource set can be allocated to the collaborative reserved user set that has not been matched and the entire reuse user set. Using D2D user pairs as left nodes and available resource blocks as right nodes, the edge weights are calculated by combining the service priority weights of D2D user pairs, the channel capacity of the corresponding resource blocks, the resource occupancy status, and the reservation validity period, and a weighted bipartite graph is constructed. Invalid edges that cannot achieve effective matching in a weighted bipartite graph are removed, and only valid matching edges are retained.

6. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 5, characterized in that, The process of matching and allocating users and resource blocks using the weighted Hungarian algorithm includes: The left and right vertex labels of the weighted bipartite graph are initialized. The left vertex label of the cooperative reserved user set is taken as the maximum weight of all valid edges of the user, and the left vertex label of the reused user set is taken as the maximum weight of all valid edges of the user. The right vertex labels of all resource blocks are initialized to 0. Based on the initialized top labels, construct an equal subgraph. Search for augmenting paths in the equal subgraph in descending order of priority, prioritizing the matching of the collaborative reserved user set and the dedicated reserved resource set. After all the collaborative reserved user sets have been matched, then perform the matching of the reused user set and the remaining resources of the general reused resource set. If no augmenting path is found, calculate the top label adjustment amount and dynamically adjust the top label; rebuild the equal subgraph and continue searching for augmenting paths until all matching users and resource blocks are completed.

7. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 6, characterized in that, The step of searching for augmenting paths in the equal subgraph in descending order of priority includes: First priority: Search the augmented path from the centralized security business users to the dedicated reserved resource set to complete the dedicated resource allocation for security business; Second priority: Search collaboration reserved users centralized control business users to the remaining resources of the dedicated reserved resource set to complete the dedicated resource allocation of control business; Third priority: Search for the augmented path from ordinary business users in the collaborative reserved user set to the remaining resources in the dedicated reserved resource set. If the dedicated reserved resource set is insufficient, search for the augmented path from it to the general reuse resource set. Fourth priority: After all users in the reserved user set for collaboration have been matched, search for an augmenting path from the reused user set to the remaining resources in the general reused resource set, and complete the resource allocation for reused users.

8. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, The step of reserving and marking resource blocks matched with users in the collaborative reservation mode includes: Resource blocks matched by users in the collaborative reservation mode are marked and managed. The marking content includes the resource block number, the reserved user identifier, the reservation priority, and the reservation validity period. During the validity period, the resource block is only used by the corresponding reserved user and will not participate in the resource allocation of other users.

9. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, The periodic monitoring of the status of reserved resource blocks, and the release of the corresponding resource blocks to the available resource pool when preset release conditions are met, includes: The link status and usage of reserved resource blocks are periodically monitored using a fixed scheduling cycle. When a reserved resource block meets any preset release condition, the resource block is immediately released to the available resource pool corresponding to the general reuse resource set. The preset release conditions include: the link quality continues to deteriorate to the point that it does not meet the minimum requirements of the cellular mode; the communication service of the corresponding reserved user is terminated; the validity period of the resource block reservation expires and no renewal request is received; the system load is lower than a preset threshold and the resource block has not been used for several consecutive scheduling cycles.

10. The vehicle-to-everything (V2D) resource allocation method based on dual-threshold collaborative reservation according to claim 1, characterized in that, After completing the matching and allocation of users and resource blocks, the following steps are also included: The base station broadcasts a cooperation awareness notification to the D2D user pair that triggered the resource reservation and to neighboring vehicles within the preset cooperation range, informing them of the relevant information of the reserved resources. Neighboring vehicles that receive a collaboration awareness notification will avoid using the reserved resource block within the reserved time window for the corresponding resource.

Images