A communication resource selection method, apparatus, device, and storage medium

Abstract

This invention discloses a communication resource selection method, apparatus, device, and storage medium, applied to vehicles in a vehicle-to-everything (V2X) network. The method includes: receiving data packets from surrounding vehicles; parsing first feedback information, second feedback information, and the current and candidate numbers of the surrounding vehicles; determining, based on the first feedback information, whether all surrounding vehicles failed to successfully receive the data packets previously broadcast by the vehicle; determining, based on the current and candidate numbers of the surrounding vehicles, whether the vehicle's current number is experiencing a resource conflict; if either condition is met, reselecting a number; updating the vehicle's current number to the candidate number from the previous broadcast if there are no objections based on the second feedback information, where the candidate number was calculated based on the location information of the surrounding vehicles before the previous broadcast; and determining the communication resource based on the mapping relationship between the new number and the communication resource. This invention achieves autonomous selection of communication resources by dynamically adjusting vehicle numbers, effectively reducing resource conflicts.

Description

Technical Field

[0001] This invention relates to vehicle-to-everything (V2X) communication technology, specifically to a method, apparatus, device, and storage medium for selecting communication resources. Background Technology

[0002] Currently, resource allocation modes for direct links in New Radio Vehicle-to-Everything (NR-V2X) networks can be divided into two types: one is a base station-controlled resource allocation mode, where base stations schedule transmission resources for V2X terminals on the direct link within the cellular network coverage area; the other is a terminal-autonomous resource selection mode based on perception, where terminals autonomously select resources from a resource pool based on perception information. Since mode two has a wider range of applications, and the hidden terminal problem in NR-V2X networks affects data packet transmission efficiency (i.e., two transmitting nodes in a wireless network simultaneously sending data to the same receiving node without mutual awareness, leading to signal conflicts), how to more efficiently select and utilize resources in mode two scenarios has become a key research focus.

[0003] The Sensing-Based Semi-Persistent Scheduling (SB-SPS) algorithm recommended in the 3GPP standard utilizes sensing information to mitigate conflicts in broadcast resources between vehicles to some extent. However, it does not effectively address the hidden terminal problem caused by the limited sensing range, resulting in a higher probability of data packet conflicts and making it unsuitable for the high reliability requirements of vehicle-to-everything (V2X) scenarios. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a communication resource selection method, apparatus, device, and storage medium that can extend the vehicle's sensing range, alleviate the problem of hidden terminals between vehicles, effectively reduce the probability of data packet collisions, and improve the average success rate of broadcast data packets from each vehicle.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] A communication resource selection method, applied to vehicles in a vehicle-to-everything (V2X) network, includes the following steps:

[0007] Receive data packets broadcast by surrounding vehicles and obtain the first feedback information, second feedback information, current number, and candidate number from the surrounding vehicles; wherein the first feedback information indicates the statistics of the surrounding vehicles on the reception status of the data packets broadcast by this vehicle in the previous round, and the second feedback information indicates whether the surrounding vehicles have any objections to the candidate number broadcast by this vehicle in the previous round.

[0008] Iterate through the first feedback information to determine if all surrounding vehicles failed to receive the data packet broadcast by this vehicle in the previous round; iterate through the current number and candidate number of surrounding vehicles to determine if the current number of this vehicle is the same as the current number of any surrounding vehicle or the candidate number of any vehicle in front; if any of the above conditions are met, then select a new current number for this vehicle; iterate through the second feedback information to determine if any surrounding vehicles object to the candidate number broadcast by this vehicle in the previous round; if there is no objection, then update the current number of this vehicle to the candidate number broadcast by this vehicle in the previous round; where the candidate number broadcast by this vehicle in the previous round is calculated based on the position information of surrounding vehicles at that time before the previous round of broadcast;

[0009] Based on the predetermined mapping relationship between vehicle number and communication resources, the communication resources used by this vehicle for broadcasting data packets are determined according to the current vehicle number.

[0010] Furthermore, the communication resources include sub-channels and time slots. The mapping relationship between vehicle numbers and communication resources is as follows: each vehicle number uniquely corresponds to an initial sub-channel number and a time slot number. The initial sub-channel number is mapped from the vehicle number according to the principle of non-overlapping frequency bands, and the time slot number is mapped from the vehicle number according to the principle of uniform dispersion in the time domain.

[0011] Furthermore, the calculation method for the starting sub-channel number is as follows: the integer part of the quotient obtained by dividing the vehicle number by the total number of available time slots is multiplied by the difference obtained by subtracting the number of sub-channels that need to be occupied from the total number of sub-channels allocated to the spectrum resources of the vehicle-to-everything (V2X) communication scenario, and then one is added to obtain the starting sub-channel number.

[0012] Furthermore, the time slot number is calculated as follows: the vehicle number is modulo the number of radio frames within a time window, and then multiplied by the number of available time slots in each radio frame to obtain the first intermediate value; the vehicle number is modulo the total number of available time slots, and then divided by the number of radio frames, and the integer part of the quotient is taken to obtain the second intermediate value; the first intermediate value is subtracted from the second intermediate value, and then the number of available time slots in each frame is added to obtain the time slot number.

[0013] Furthermore, the method for reselecting a number for this vehicle is as follows: determine the range of available numbers based on the total number of available time slots, exclude numbers already occupied by surrounding vehicles or candidate numbers of any vehicle in front from the range of available numbers, and randomly select a number from the remaining numbers.

[0014] Furthermore, the number of vehicles already occupied by surrounding vehicles includes the current number of the vehicle occupying the resource obtained by reverse calculation through the sensing channel, and the current number of the surrounding vehicles parsed from the received data packets. The method for obtaining the current number of the vehicle occupying the resource by reverse calculation through the sensing channel is as follows: based on the mapping relationship between vehicle numbers and communication resources, a first reverse calculation number is calculated according to the currently occupied time slot number, and the first reverse calculation number is added to the total number of available time slots to obtain a second reverse calculation number. If the starting sub-channel number is one, both the first and second reverse calculation numbers are used as the current number of the vehicle occupying the resource obtained by reverse calculation. If the starting sub-channel number is not one, the second reverse calculation number is determined as the current number of the vehicle occupying the resource obtained by reverse calculation.

[0015] Furthermore, the method for determining the candidate number of any vehicle ahead is as follows: obtain the position information, speed information, and position and speed corresponding time of the surrounding vehicles from the data packets broadcast by the surrounding vehicles; calculate the predicted position of the surrounding vehicles based on the position information, speed information, position and speed corresponding time, and the current time; sort all the predicted positions of the surrounding vehicles to determine the vehicle in front of the current vehicle; traverse the candidate numbers of the surrounding vehicles to determine the candidate number of the vehicle in front of the current vehicle.

[0016] Furthermore, the calculation method for the candidate number of this vehicle is as follows: based on the vehicles in front of this vehicle, determine the number of the nearest preceding vehicle, and obtain the candidate number of this vehicle in a cyclical order within the numbering space based on the number of the nearest preceding vehicle.

[0017] Furthermore, the method also includes: maintaining a vehicle information table, which stores the location information, speed information, current number, candidate number, first feedback information, second feedback information, and the time corresponding to speed and location of surrounding vehicles, and periodically deleting records in the vehicle information table that exceed a specified time threshold.

[0018] The present invention also provides a communication resource selection device, applied to vehicles in a vehicle-to-everything (V2X) network, comprising:

[0019] The data acquisition module is used to receive data packets broadcast by surrounding vehicles and obtain the first feedback information, second feedback information, current number, and candidate number from the surrounding vehicles. The first feedback information indicates the statistics of the surrounding vehicles on the reception status of the data packets broadcast by this vehicle in the previous round, and the second feedback information indicates whether the surrounding vehicles have any objections to the candidate number broadcast by this vehicle in the previous round.

[0020] The number determination module is used to iterate through the first feedback information to determine whether all surrounding vehicles have failed to receive the data packet broadcast by this vehicle in the previous round; it iterates through the current number and candidate number of surrounding vehicles to determine whether the current number of this vehicle is the same as the current number of any surrounding vehicle or the candidate number of any vehicle in front; if any of the above conditions are met, a new current number is selected for this vehicle; it iterates through the second feedback information to determine whether any surrounding vehicles object to the candidate number broadcast by this vehicle in the previous round; if there is no objection, the current number of this vehicle is updated to the candidate number broadcast by this vehicle in the previous round; wherein the candidate number broadcast by this vehicle in the previous round is calculated based on the position information of surrounding vehicles at that time before the previous round of broadcast;

[0021] The resource determination module is used to determine the communication resources for broadcasting data packets for this vehicle based on the pre-determined mapping relationship between vehicle numbers and communication resources, according to the current vehicle number.

[0022] The present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the computer program to implement the communication resource selection method described above.

[0023] The present invention also provides a vehicle including the communication resource selection device or electronic device described above.

[0024] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the communication resource selection method described above.

[0025] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the communication resource selection method described above.

[0026] Beneficial Effects: This invention analyzes data packets broadcast by surrounding vehicles to obtain feedback information from each vehicle regarding the previous round of broadcast data packets and candidate numbers. This feedback information is used as the basis for whether to trigger a reselection or update of the vehicle's number. The candidate numbers are calculated based on the location information of surrounding vehicles, allowing the vehicle's number to dynamically adjust according to changes in the relative position of vehicles, avoiding number conflicts caused by proximity. The combined use of location information and feedback information indirectly expands the vehicle's perception range, greatly alleviating data packet conflicts caused by concealed terminals in vehicle-to-everything (V2X) networks, effectively reducing the probability of data packet conflicts and improving the average successful reception rate of broadcast data packets from each vehicle. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a scenario model for the vehicle-to-everything (V2X) edge computing system of the present invention;

[0028] Figure 2 The overall flowchart of the communication resource selection method provided by the present invention;

[0029] Figure 3 This is an example diagram illustrating the relationship between vehicle number and communication resource location according to the present invention;

[0030] Figure 4 A detailed flowchart of the communication resource selection method provided by the present invention. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will now be clearly and completely described in conjunction with the accompanying drawings.

[0032] Vehicle-to-everything (V2X) communication, through real-time and effective information exchange between vehicles and their surroundings (including roads), can not only identify and avoid dangerous situations in advance, reducing accidents, but also plan driving routes from a global perspective, alleviating traffic congestion. The core of V2X technology lies in the reliable and efficient interaction between vehicles and other entities; therefore, ensuring high-reliability, low-latency communication between different entities is a key research focus. The gradual maturation and implementation of 5G mobile communication technology has provided many existing application scenarios with more advanced technologies and available resources. To utilize existing technologies and resources more efficiently, the resource allocation issue in V2X communication has attracted widespread attention.

[0033] Vehicle-to-vehicle (V2V) communication scenarios in areas without base station coverage, such as... Figure 1 As shown. Assuming the system operates in discrete time slots, vehicles generate two types of data packets that need to be broadcast, namely... The Cooperative Awareness Messages (CAM) data packets generated periodically and the data packet generation time interval satisfy the following: The non-periodic decentralized environmental notification message (DENM) data packet, where N is a value satisfying the mean. A random variable with an exponential distribution. This is the end-to-end latency limit for DENM packets. This refers to the end-to-end delay limit for CAM data packets. Under the premise of meeting the data packet delay limit, vehicles autonomously select communication resources to broadcast data packets, and the selection of communication resources should maximize the successful reception rate of data packets. This invention provides a communication resource selection method, which involves numbering vehicles and selecting corresponding resources to send data packets based on their numbers. Vehicle number i uses... express.

[0034] Communication resources in the system are represented by sub-channels and time slots. It is assumed that the total spectrum resources allocated to the vehicle-to-everything (V2X) communication scenario are... There are three sub-channels with equal bandwidth, denoted as... The vehicle divides communication resources into several equal time windows based on the minimum delay limit T of the two services (i.e., broadcasting two types of data packets), i.e., the length of the time window. Each time window is contiguous, and the distribution of time slots available for NR-V2V communication within each window is identical. It is assumed that each time window contains... The number of available time slots (i.e., the total number of available time slots below) is denoted as Each sub-channel in each time slot can be used for vehicle-to-everything (V2X) data transmission. There are N sub-channels within each time window. frame There are N wireless frames, each frame contains N slot There are [number] time slots available for NR-V2V communication. To simplify the description and calculation of the resource structure, it is assumed that the delay limits for both types of data packets are multiples of 10. Therefore, the time window length is a multiple of 10, and the number of radio frames within one time window is [number]. The number of time slots used for communication in each frame is .

[0035] This invention establishes the mapping relationship between vehicle numbers and communication resources as follows: each vehicle number uniquely corresponds to an initial sub-channel number and a timeslot number. The initial sub-channel number is mapped from the vehicle number according to the principle of non-overlapping frequency bands, and the timeslot number is mapped from the vehicle number according to the principle of uniform time-domain distribution. Specifically, the initial sub-channel number is obtained by multiplying the integer part of the quotient (vehicle number divided by the total number of available timeslots) by the difference between the total number of sub-channels allocated to the spectrum resources for the vehicle-to-everything (V2X) communication scenario and the number of sub-channels that need to be occupied, and then adding one. Initial Sub-Channel Number The calculation formula is expressed as follows:

[0036] (1)

[0037] in The number of sub-channels required to send data packets can be calculated based on physical layer information such as the size of the data packets to be broadcast and the signal modulation method. This invention will not elaborate on this. The control packets generated by the broadcast data packets occupy only one sub-channel. This indicates rounding down, meaning the starting sub-channel is... .

[0038] The time slot number is obtained as follows: The vehicle number is modulo the number of radio frames within a time window, then multiplied by the number of available time slots in each radio frame to obtain a first intermediate value; the vehicle number is modulo the total number of available time slots, divided by the number of radio frames, and the integer part of the quotient is obtained as a second intermediate value; the first intermediate value is subtracted from the second intermediate value, and the number of available time slots in each frame is added to obtain the time slot number. The formula is expressed as:

[0039] (2)

[0040] Even if the time slot is Where % represents modulo.

[0041] Assumption , , , , According to formula (1), we have: According to formula (2), we have: The communication resources for vehicles with different numbers are shown in Table 1.

[0042] Table 1. Examples of communication resource allocation corresponding to vehicle numbers

[0043]

[0044] As can be seen from the vehicle communication resource locations numbered 0 to 4 in Table 1, the starting sub-channel number is 1, but the time slots used by adjacent vehicle broadcast data packets are not adjacent in the time domain and are evenly distributed in the time domain; as can be seen from the vehicle communication resource locations numbered 0 and 50 in Table 1, the time slot numbers are the same, but the sub-channels do not overlap, which reflects the principle of non-overlapping frequency bands.

[0045] Each vehicle determines its broadcast data packet's time slot and starting sub-channel using a mapping formula based on its current vehicle number. Within that time slot, the vehicle's continuous broadcasts, starting from that starting sub-channel... On one sub-channel, data packets are broadcast, while in other time slots they are in receiving or sensing state and do not send data. This effectively reduces the probability of data packet collisions and improves the average success rate of broadcast data packets from each vehicle.

[0046] Reference Figure 2 This invention proposes a communication resource selection method for vehicles in the Internet of Vehicles (IoV), comprising the following steps:

[0047] S1. Receive data packets broadcast by surrounding vehicles and obtain the first feedback information, second feedback information, current number, and candidate number from the surrounding vehicles; wherein the first feedback information indicates the statistics of the surrounding vehicles on the reception status of the data packets broadcast by this vehicle in the previous round, and the second feedback information indicates whether the surrounding vehicles have any objections to the candidate number broadcast by this vehicle in the previous round.

[0048] All vehicles using this resource selection mechanism need to maintain a vehicle information table, which stores information about other vehicles in the vicinity as perceived by the vehicle. Assume this vehicle uses... It indicates that other vehicles use It indicates that the vehicle The stored vehicle information table is for vehicles The records contain the following information: vehicle Location information, vehicles Speed ​​information, vehicles Location and speed information corresponding to time and vehicle Feedback information regarding this vehicle (including first and second feedback information), vehicle Current number, vehicle Candidate numbers, vehicles Whether the previous data packet was successfully received. Each broadcast from every vehicle carries its location information, speed information, current number, candidate number, feedback information, and the corresponding time for speed and location. Among these, the vehicle... Feedback information for this vehicle includes primary feedback information, used to instruct the vehicle. Whether the data packet from the previous broadcast by this vehicle has been received; and the second feedback information, used to instruct the vehicle. Are there any objections to the vehicle number update plan (i.e., the candidate number for this vehicle) announced in the previous round?

[0049] The first feedback information is about the status of data packet reception. Each vehicle carries a segment of information in its broadcast data packet indicating whether it has received broadcast data packets from other vehicles. Assume the first feedback information accounts for N... r Position, for vehicle In other words, the first to Nth of the first feedback information it sends to other vehicles r The positions correspond to the vehicles in sequence. For the number from arrive The feedback of data packets broadcast by the vehicle. For example, N in the first feedback information. r If a bit in the sequence is 1, it indicates that the data packet broadcast by the vehicle with the corresponding number was not received by the vehicle. Successfully received. The maximum value for the vehicle number under current conditions, based on the number of available time slots for NR-V2V communication in each time window. The calculation yielded: That is, the range of selectable vehicle numbers is... .in The scaling factor can be determined based on the number of sub-channels allocated to vehicle communication and the number of sub-channels required by the vehicle's data packets. Specifically... , The number of sub-channels required to generate the maximum number of data packets for a vehicle.

[0050] The second feedback information concerns the vehicle number update plan, which involves each vehicle broadcasting its candidate vehicle number to other vehicles. Inevitably, conflicts will occur between candidate vehicle numbers. For example, vehicles... The calculated candidate number is 5, and the vehicle... If the calculated candidate number is also 5, then there is a conflict between the two candidate numbers. This invention uses second feedback information to help resolve this conflict. In the case of identical candidate numbers, the candidate number of the vehicle traveling further back in the direction of travel will be opposed by other vehicles, and these objections are broadcast via the second feedback information. Each vehicle will carry a segment of information in the broadcast data packet to indicate whether there are any objections to the numbering update plans of other vehicles. Assume that the second feedback information accounts for N... T Position, from the 1st to the Nth T The bits correspond sequentially to the first available time slot to the Nth slot in the time window. T Available time slots. If a bit is 1, it indicates that the vehicle number update plan broadcast in the time slot corresponding to that bit has been opposed by this vehicle. For example, vehicle To oppose vehicles The candidate number, then the vehicle The vehicle will be in the second feedback information Setting the slot number corresponding to the broadcast data packet to 1 indicates opposition to the number update plan for broadcasting in that slot.

[0051] The first feedback information, second feedback information, current number, and candidate number of surrounding vehicles extracted from the received data packet are used by the receiving vehicle to determine whether it needs to update its own number.

[0052] Preferably, this vehicle periodically deletes records from other stored vehicle information that exceed a preset time threshold. It iterates through each stored vehicle information record; if the time difference between the corresponding time of a certain vehicle information record and the current time is greater than the threshold... If so, then delete the vehicle information.

[0053] S2. Iterate through the first feedback information to determine if all surrounding vehicles have failed to receive the data packet broadcast by this vehicle in the previous round; iterate through the current number and candidate number of surrounding vehicles to determine if the current number of this vehicle is the same as the current number of any surrounding vehicle or the candidate number of any vehicle in front; if any of the above conditions are met, then reselect a current number for this vehicle; iterate through the second feedback information to determine if any surrounding vehicles object to the candidate number broadcast by this vehicle in the previous round; if there is no objection, then update the current number of this vehicle to the candidate number broadcast by this vehicle in the previous round; where the candidate number broadcast by this vehicle in the previous round is calculated based on the position information of surrounding vehicles at that time before the previous round of broadcast;

[0054] Iterate through the first feedback messages. For each message, locate the bit corresponding to the vehicle's ID. If that bit is 1, it indicates that the sending vehicle failed to receive the data packet from its previous broadcast. When all surrounding vehicles send first feedback messages with the bit corresponding to the vehicle's ID set to 1, it is determined that all surrounding vehicles failed to receive the data packet from the vehicle's previous broadcast. At this point, a new ID is selected for the vehicle.

[0055] Iterate through the current and candidate numbers of surrounding vehicles in the vehicle information table. If a resource conflict is found between the vehicle's own number and the current number of any surrounding vehicle or the candidate number of any vehicle in front, then select a new number for the vehicle.

[0056] If any of the above conditions are met, the vehicle will reselect a random number based on the given data packet parameters, broadcast parameters, the number of available communication resources, and the vehicle's perception of the surrounding environment. Specifically, the method for the vehicle to reselect a number is as follows: the range of available numbers is determined based on the total number of available time slots, i.e. Exclude numbers that are already occupied by surrounding vehicles from the available number range, and randomly select one number from the remaining numbers.

[0057] The number of vehicles already occupied by surrounding vehicles includes the current vehicle number occupying the resource obtained through reverse engineering via the sensing channel, as well as the current numbers of surrounding vehicles and candidate numbers of vehicles ahead, parsed from the received data packets. The method for obtaining the current number of a vehicle occupying a resource through reverse engineering via the sensing channel is as follows: Based on the mapping relationship between vehicle numbers and communication resources, a first reverse-engineered number is calculated according to the currently occupied time slot number; the first reverse-engineered number is then added to the total number of available time slots to obtain a second reverse-engineered number; if the starting sub-channel number is one, both the first and second reverse-engineered numbers are used as the reverse-engineered current vehicle number occupying the resource; if the starting sub-channel number is not one, the second reverse-engineered number is determined as the reverse-engineered current vehicle number occupying the resource. Specifically, assuming that the starting sub-channel number in a certain channel busy information is... The time slot occupied is the first time slot in the time frame. Available time slots. By combining the mapping relationship between vehicle number and communication resources with the channel busy information, the source of the data packet corresponding to the busy information can be deduced. According to formulas (1) and (2) and Table 1, the vehicle numbers occupying each time slot in each radio frame show a certain pattern. Based on this pattern, a reverse deduction formula can be designed. First, calculate which radio frame the current time slot is in, and then determine which time slot in the radio frame the current time slot belongs to based on the number of time slots used for communication in each radio frame. The starting sub-channel number is The time slot occupied is the first one in the time window. The data packets for the available time slots originate from the numbered... Vehicles or vehicles with the number For the vehicles mentioned above, in the reverse formula, Which radio frame is it located in within the time window? In which V2V time slot within the radio frame is it located? % indicates rounding down, and % indicates modulo. The former is the first reverse-order number, and the latter is the second reverse-order number. If the starting sub-channel is not 1, it can be further determined that the data packet comes from the latter.

[0058] The method for determining the candidate numbers of the vehicles ahead is as follows: Obtain the position information, speed information, and corresponding time of position and speed of the surrounding vehicles from the data packets broadcast by the surrounding vehicles; calculate the predicted positions of the surrounding vehicles based on the position information, speed information, corresponding time of position and speed, and the current time; sort all the predicted positions of the surrounding vehicles to determine the vehicles in front of the current vehicle; traverse the candidate numbers of the surrounding vehicles to determine the candidate number of the vehicle in front of the current vehicle. Specifically, refer to... Figure 1 A Cartesian coordinate system is established with the vehicle's current position as the origin, the vehicle's forward direction as the x-axis, and the y-axis perpendicular to the forward direction and pointing to the left. The position and velocity information of surrounding vehicles obtained from the analysis are converted into coordinates in this Cartesian coordinate system. Based on the position and velocity information of surrounding vehicles and their corresponding times, the predicted positions of surrounding vehicles are calculated in conjunction with the current time. Assume that the surrounding vehicles are V... j Location information is Speed ​​information is Calculate vehicles Predicted location for: , Where t represents V from other vehicle information stored in this vehicle. j The corresponding time of location information This indicates the current time. All vehicles are sorted from largest to smallest x-axis coordinate. If two vehicles have similar x-axis coordinates, and the difference is less than a preset threshold, they are sorted from largest to smallest y-axis coordinate. Based on the sorting results, the positions of the vehicles in front of this vehicle are determined from closest to furthest, and the candidate numbers of the vehicles in front are monitored.

[0059] If it detects other vehicles with the current number nearby or other vehicles with candidate number j ahead, then change the number. Exclude from the range of available numbers. Randomly select a number from the remaining available numbers as the vehicle number, and complete the vehicle number update.

[0060] If the first feedback information indicates that the vehicle's previous broadcast data was received by any surrounding vehicle, or if there is no conflict with the vehicle's current number, then the number reselection action will not be performed.

[0061] However, no conflict is only the minimum requirement and does not mean that the current number is the optimal number. In order to enable vehicles to continuously and dynamically find the optimal number, the second feedback information is then traversed to determine whether anyone has objected to the candidate number broadcast by this vehicle in the previous round. If no vehicle has objected to the candidate number broadcast by this vehicle in the previous round, then the vehicle number is updated to the candidate number broadcast in the previous round.

[0062] The calculation method for the candidate number of this vehicle is as follows: Based on the vehicles in front of this vehicle, determine the number of the nearest preceding vehicle. Then, based on this nearest preceding vehicle's number, obtain the candidate number of this vehicle in a cyclical manner within the numbering space. The specific method for determining the preceding vehicle's number is the same as before, except that it is calculated based on the position information of surrounding vehicles before the previous broadcast; this will not be elaborated here. Assume the number of the nearest preceding vehicle is i. pre The candidate number is obtained by adding one to the given number, then adding one to the maximum available number and taking the modulo. The formula is as follows: ,in The maximum value for the vehicle number is calculated as described in step S1.

[0063] S3. Based on the predetermined mapping relationship between vehicle number and communication resources, determine the communication resources of this vehicle for broadcasting data packets according to the current number of this vehicle, that is, use formula (1) and formula (2) to calculate the starting sub-channel number and time slot number.

[0064] Vehicles use resource broadcast data packets corresponding to their vehicle numbers. Each vehicle's broadcast data packet contains its own status (position, speed, time corresponding to position and speed, current number, candidate number), as well as first feedback information on the reception of other vehicles' data packets and second feedback information on the number update plan of other vehicles. The vehicle checks its transmission buffer sequence for any data packets waiting to be sent. If CAM / DENM data packets are waiting to be sent, they are merged into a single data packet; if no data packets are waiting to be sent, a control data packet is generated; this generated control data packet is then used as the data packet to be sent.

[0065] The above describes vehicles in the Internet of Vehicles (IoV). After sending a round of broadcast data packets, the vehicle updates its own number based on received feedback information and the status information of other vehicles. This invention establishes a mapping relationship between vehicle numbers and communication resources. By considering location information and perception information (i.e., the current number, candidate number, position speed and corresponding time of surrounding vehicles, two types of feedback information, and the number of vehicles occupying resources) during the calculation process, vehicles can dynamically adjust their numbers according to their relative position with surrounding vehicles, thereby reducing the possibility of data packet collisions.

[0066] Figure 3 An example of communication resource allocation is illustrated. Within a time window, communication resources are divided into five independent sub-channels in terms of frequency. Different sub-channels can transmit data in parallel. In terms of time, the allocation is divided into 1 to 50 time slots of equal length. Vehicles transmit data only within their assigned time slots. In the scenario, every 50 vehicles form a group, represented by blue and green, and are assigned to time slots 1 to 50. Combined with the five sub-channels, this achieves conflict-free access for up to 50 vehicles. Specifically, blue vehicles correspond to blue resource blocks and use sub-channel 1 and some time slots of sub-channels 2 to 4 to transmit data; green vehicles correspond to green resource blocks and use sub-channel 5 and some time slots of sub-channels 2 to 4 to transmit data. The overlap of vehicles at different locations in the same time slot / sub-channel is represented by blue-green stripes, indicating resource conflicts. This invention dynamically selects communication resources by mapping vehicle numbers to communication resources and combining location information, effectively reducing the probability of data packet collisions and improving the average successful reception rate of broadcast data packets for each vehicle.

[0067] In specific implementation, before step S1, the vehicle is assigned an initial number when it just enters the road segment. After step S2 and before step S3, considering that the vehicle numbers in the traffic flow may be discontinuous due to overtaking, diversion, etc., the candidate vehicle numbers are dynamically updated in real time, that is, a new candidate number is determined before each data packet is sent.

[0068] Reference Figure 4 In one specific embodiment, it is assumed that this vehicle uses This method specifically includes the following steps:

[0069] (1) Vehicle Between the two reserved resources, the system continuously senses the channel and processes received data packets, listening until the vehicle detects that the channel is busy. Based on the location of the occupied resource, a reverse calculation formula is designed to deduce the vehicle number occupying that resource. Assume that the starting sub-channel number in a certain channel busy information is... The time slot occupied is the first time slot in the time frame. If the available time slot is 1, then the 1st available time slot will be occupied. The data packets for the available time slots originate from the numbered... Vehicles or vehicles with the number The vehicles, among which % indicates rounding down, and % indicates modulo. If the starting subchannel is not 1, it can be further determined that the data packet comes from the latter.

[0070] After determining the vehicle number occupying the resource, the vehicle waits to receive the data packet corresponding to that number. If the data packet corresponding to the number is not received, the vehicle queries its stored other vehicle information table to record that the data packet sent by the vehicle with that number was not successfully received by this vehicle; if the vehicle successfully receives the data packet corresponding to the number, the vehicle queries its stored other vehicle information table to determine whether there is information for the vehicle with that number, and creates or updates the vehicle information corresponding to that number as appropriate.

[0071] (2) Vehicles Based on the given data packet parameters, broadcast parameters, available communication resources, and the vehicle's perception of its surroundings, the vehicle selects a random number as its initial number. The specific steps include: determining the range of available numbers based on the number of available time slots in each time window. ,in This represents the maximum value of the vehicle number under the current conditions. The number of available time slots in time window T; using sensing information to exclude unselectable numbers, that is, excluding numbers already occupied by other vehicles or candidate numbers to be occupied, if a vehicle If a vehicle with the current ID or a candidate new ID j is detected in the vicinity, then the ID will be changed. Exclude from the range of available numbers; randomly select a number from the remaining available numbers.

[0072] (3) Vehicles Outdated vehicle information is deleted from storage based on time. First, the current time is retrieved. Then, each piece of vehicle information in the storage is iterated over. If the time difference between the corresponding time of a vehicle's information and the current time is greater than a threshold... If so, then delete the vehicle information.

[0073] (4) Vehicles Based on the feedback information on the reception status of data packets received since the last data packet broadcast and other vehicle candidate numbers, a decision is made on whether to reselect a random number for the vehicle. If no other vehicle has received the data packet broadcast by this vehicle in the last broadcast, or if this vehicle's number conflicts with the current number of any other vehicle or the candidate number of any vehicle ahead, a new number is randomly selected for this vehicle based on the perception information and location information. The specific method for reselecting the number is the same as the initial number selection method in step (2).

[0074] (5) Vehicles Based on the feedback information received since the last data packet broadcast regarding the number update plan, a decision is made as to whether to update the vehicle's number to the candidate number from the previous broadcast. This feedback information is iterated through; if no vehicle objects to the candidate number broadcast in the previous round, the vehicle's number is updated to that candidate number.

[0075] (6) Vehicles New candidate numbers are determined based on sensing and location information, and these new candidate numbers are used for the next broadcast. Specific steps include:

[0076] 1) Establish a Cartesian coordinate system with the vehicle's current position as the origin, the vehicle's forward direction as the x-axis, and the leftward direction perpendicular to the forward direction as the y-axis, as follows: Figure 1 As shown.

[0077] 2) Transfer vehicle V from the vehicle information table j Position and velocity information are represented using this coordinate system.

[0078] 3) Utilize vehicle V in the vehicle information table j Location information and speed information Calculate vehicles Current location ,in , Where t represents V from other vehicle information stored in this vehicle. j The corresponding time of location information Indicates the current moment.

[0079] 4) Traverse the entire vehicle information table, repeatedly executing steps 2) and 3) until the current location information of all vehicles is obtained.

[0080] 5) Sort all vehicles in descending order of their x-axis coordinates. If two vehicles have similar x-axis coordinates, sort them in descending order of their y-axis coordinates.

[0081] 6) Based on the sorting results, obtain the number i of the vehicle closest to your vehicle. pre Using formula A new candidate number has been obtained.

[0082] (7) Vehicles It generates feedback on the reception of data packets from other vehicles and feedback on other vehicle number update plans, and adds this feedback information to the data packets. This is based on the reception status of surrounding vehicles' broadcast data packets since the last broadcast, the vehicle number update plans in the received data packets, and vehicle V... i Perception information of surrounding vehicles.

[0083] Feedback information regarding data packet reception accounts for Nr Let's assume the vehicle's number is i. Then, the first to Nth positions of this feedback information... r The digits correspond sequentially to the vehicle pair number from... arrive The feedback of the vehicle broadcast data packet. If a certain bit is 1, it indicates that the data packet broadcast by the vehicle with the corresponding number has not been received by vehicle V. i Successfully received. Combining the vehicle numbers corresponding to all failed-to-receive data packets, vehicle V... i Generate feedback information on the data packet reception status of other vehicles.

[0084] Feedback information regarding the numbering update plan accounts for N T Position, from the 1st to the Nth T The bits correspond sequentially to the first available time slot to the Nth slot in the time window. T Available time slots. If a bit is 1, it indicates that the vehicle number update plan broadcast in the time slot corresponding to that bit has been opposed by this vehicle. Combined with vehicle V i The information from all received data packets is used to update the vehicle's identification number plan for each vehicle. If vehicle V... j If a candidate new number does not use the same spectrum resource as the vehicle ahead in its direction of travel, then vehicle V i Vehicle V will be included in the number update plan feedback. j Setting the corresponding position to 0 indicates agreement, otherwise setting it to 1 indicates disagreement.

[0085] (8) The vehicle determines the communication resources used for broadcasting the data packet based on its own number and then broadcasts the data packet. Among them, vehicle V... i The starting sub-channel number occupied is That is, the starting sub-channel is Vehicle V i The time slot number occupied is That is, using time slots is .

[0086] (9) The vehicle continuously senses the channel and processes the received data packets, and the specific steps are the same as in step (1).

[0087] (10) The vehicle determines whether there is a data packet and decides whether to merge CAM / DENM or generate a small data packet for transmission, and jumps to step (3) to continue the process.

[0088] The present invention also provides a communication resource selection apparatus for implementing the above-described communication resource selection method, the apparatus comprising:

[0089] The data acquisition module is used to receive data packets broadcast by surrounding vehicles and obtain the first feedback information, second feedback information, current number, and candidate number from the surrounding vehicles. The first feedback information indicates the statistics of the surrounding vehicles on the reception status of the data packets broadcast by this vehicle in the previous round, and the second feedback information indicates whether the surrounding vehicles have any objections to the candidate number broadcast by this vehicle in the previous round.

[0090] The number determination module is used to iterate through the first feedback information to determine whether all surrounding vehicles have failed to receive the data packet broadcast by this vehicle in the previous round; it iterates through the current number and candidate number of surrounding vehicles to determine whether the current number of this vehicle is the same as the current number of any surrounding vehicle or the candidate number of any vehicle in front; if any of the above conditions are met, a new current number is selected for this vehicle; it iterates through the second feedback information to determine whether any surrounding vehicles object to the candidate number broadcast by this vehicle in the previous round; if there is no objection, the current number of this vehicle is updated to the candidate number broadcast by this vehicle in the previous round; wherein the candidate number broadcast by this vehicle in the previous round is calculated based on the position information of surrounding vehicles at that time before the previous round of broadcast;

[0091] The resource determination module is used to determine the communication resources for broadcasting data packets for this vehicle based on the pre-determined mapping relationship between vehicle numbers and communication resources, according to the current vehicle number.

[0092] It should be understood that the communication resource selection device in this embodiment can implement all the technical solutions in the above communication resource selection method embodiments. The functions of each of its functional modules can be specifically implemented according to the methods in the above method embodiments. The specific implementation process can be referred to the relevant descriptions in the above method embodiments, which will not be repeated here.

[0093] The present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the computer program to implement the communication resource selection method described above.

[0094] The present invention also provides a vehicle including the communication resource selection device or electronic device described above.

[0095] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the communication resource selection method described above.

[0096] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the communication resource selection method described above.

Claims

1. A method for selecting communication resources, characterized in that, The method, applied to vehicles in the Internet of Vehicles (IoV), includes: Receive data packets broadcast by surrounding vehicles and obtain the first feedback information, second feedback information, current number, and candidate number from the surrounding vehicles; wherein the first feedback information indicates the statistics of the surrounding vehicles on the reception status of the data packets broadcast by this vehicle in the previous round, and the second feedback information indicates whether the surrounding vehicles have any objections to the candidate number broadcast by this vehicle in the previous round. Iterate through the first feedback information to determine if all surrounding vehicles failed to receive the data packet broadcast by this vehicle in the previous round; iterate through the current number and candidate number of surrounding vehicles to determine if the current number of this vehicle is the same as the current number of any surrounding vehicle or the candidate number of any vehicle in front; if any of the above conditions are met, then select a new current number for this vehicle; iterate through the second feedback information to determine if any surrounding vehicles object to the candidate number broadcast by this vehicle in the previous round; if there is no objection, then update the current number of this vehicle to the candidate number broadcast by this vehicle in the previous round; where the candidate number broadcast by this vehicle in the previous round is calculated based on the position information of surrounding vehicles at that time before the previous round of broadcast; Based on the predetermined mapping relationship between vehicle number and communication resources, the communication resources used by this vehicle for broadcasting data packets are determined according to the current vehicle number.

2. The method according to claim 1, characterized in that, The communication resources include sub-channels and time slots. The mapping relationship between vehicle numbers and communication resources is as follows: each vehicle number uniquely corresponds to an initial sub-channel number and a time slot number. The initial sub-channel number is mapped from the vehicle number according to the principle of non-overlapping frequency bands, and the time slot number is mapped from the vehicle number according to the principle of uniform dispersion in the time domain.

3. The method according to claim 2, characterized in that, The starting sub-channel number is calculated as follows: the integer part of the quotient obtained by dividing the vehicle number by the total number of available time slots is multiplied by the difference obtained by subtracting the number of sub-channels that need to be occupied from the total number of sub-channels allocated to the spectrum resources of the vehicle-to-everything (V2X) communication scenario, and then one is added to obtain the starting sub-channel number.

4. The method according to claim 2, characterized in that, The time slot number is calculated as follows: Take the vehicle number modulo the number of radio frames within a time window, multiply it by the number of available time slots in each radio frame to obtain the first intermediate value; take the vehicle number modulo the total number of available time slots, divide it by the number of radio frames, and take the integer part of the quotient to obtain the second intermediate value; subtract the second intermediate value from the first intermediate value, and add the number of available time slots in each frame to obtain the time slot number.

5. The method according to claim 2, characterized in that, The method for reselecting a number for this vehicle is as follows: determine the range of available numbers based on the total number of available time slots, exclude numbers that have been occupied by surrounding vehicles or candidate numbers of any vehicle in front from the range of available numbers, and randomly select a number from the remaining numbers.

6. The method according to claim 5, characterized in that, The number of vehicles already occupied by surrounding vehicles includes the current vehicle number occupying the resource obtained by reverse calculation through the sensing channel, and the current vehicle number of surrounding vehicles parsed from the received data packet. The method for obtaining the current vehicle number occupying the resource by reverse calculation through the sensing channel is as follows: Based on the mapping relationship between vehicle number and communication resource, a first reverse calculation number is calculated according to the currently occupied time slot number. The first reverse calculation number is added to the total number of available time slots to obtain a second reverse calculation number. If the starting sub-channel number is one, both the first and second reverse calculation numbers are used as the current vehicle number occupying the resource obtained by reverse calculation. If the starting sub-channel number is not one, the second reverse calculation number is determined as the current vehicle number occupying the resource obtained by reverse calculation.

7. The method according to claim 5, characterized in that, The method for determining the candidate number of any vehicle ahead is as follows: obtain the position information, speed information, and position and speed corresponding time of the surrounding vehicles from the data packets broadcast by the surrounding vehicles; calculate the predicted position of the surrounding vehicles based on the position information, speed information, position and speed corresponding time and the current time; sort all the predicted positions of the surrounding vehicles to determine the vehicle in front of this vehicle. Iterate through the candidate numbers of surrounding vehicles and determine the candidate number of the vehicle in front of your vehicle.

8. The method according to claim 7, characterized in that, The method for calculating the candidate number of this vehicle is as follows: Based on the vehicles in front of this vehicle, determine the number of the nearest preceding vehicle, and obtain the candidate number of this vehicle in a cyclical order within the numbering space based on the number of the nearest preceding vehicle.

9. The method according to claim 1, characterized in that, The method further includes: maintaining a vehicle information table, which stores the location information, speed information, current number, candidate number, first feedback information, second feedback information, and the time corresponding to speed and location of surrounding vehicles, and periodically deleting records in the vehicle information table that exceed a specified time threshold.

10. A communication resource selection device, applied to vehicles in a vehicle-to-everything (V2X) network, characterized in that, include: The data acquisition module is used to receive data packets broadcast by surrounding vehicles and obtain the first feedback information, second feedback information, current number, and candidate number of the surrounding vehicles from them. The first feedback information indicates the statistics of surrounding vehicles on the reception of the data packets of the vehicle's previous broadcast, and the second feedback information indicates whether surrounding vehicles have any objections to the candidate numbers of the vehicle's previous broadcast. The number determination module is used to iterate through the first feedback information to determine whether all surrounding vehicles have failed to receive the data packet broadcast by this vehicle in the previous round; it iterates through the current number and candidate number of surrounding vehicles to determine whether the current number of this vehicle is the same as the current number of any surrounding vehicle or the candidate number of any vehicle in front; if any of the above conditions are met, a new current number is selected for this vehicle; it iterates through the second feedback information to determine whether any surrounding vehicles object to the candidate number broadcast by this vehicle in the previous round; if there is no objection, the current number of this vehicle is updated to the candidate number broadcast by this vehicle in the previous round; wherein the candidate number broadcast by this vehicle in the previous round is calculated based on the position information of surrounding vehicles at that time before the previous round of broadcast; The resource determination module is used to determine the communication resources for broadcasting data packets for this vehicle based on the pre-determined mapping relationship between vehicle numbers and communication resources, according to the current vehicle number.

11. An electronic device, characterized in that, It includes a processor and a memory, the memory storing a computer program, and the processor executing the computer program to implement the communication resource selection method according to any one of claims 1 to 9.

12. A vehicle, characterized in that, Includes the communication resource selection device of claim 10 or the electronic device of claim 11.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the communication resource selection method according to any one of claims 1 to 9.

14. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the communication resource selection method according to any one of claims 1 to 9.

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