Relay Point Selection Method for Cooperative Formation Driving of Connected Vehicles in Complex Communication Environments

Abstract

The present invention discloses a relay point selection method for cooperative formation driving of connected vehicles in a complex communication environment, including: when the communication quality of vehicle cooperative formation deteriorates or communication is interrupted, using the analytic hierarchy process to score and rank several communication indicators of all connected vehicles except formation vehicles in the current scenario of vehicle cooperative formation; ranking all connected vehicles from high to low according to the scores, and selecting the top three as relay point vehicles; arbitrarily selecting at least one from the 3 relay point vehicles for permutation and combination to obtain 7 relay communication links; obtaining the communication quality levels of all relay communication links through an evaluation function; if the communication quality level of at least one of the 7 relay communication links meets the preset conditions, integrating the corresponding relay communication link into the vehicle networking architecture; otherwise, selecting the cloud platform as the communication relay point; wherein, the several communication indicators include: penetration power, multipath propagation power, time delay, propagation distance, and bandwidth.

Description

Technical Field

[0001] The present invention relates to the technical field of cooperative autonomous driving, and particularly to a relay point selection method for connected vehicle cooperative formation driving in a complex communication environment. Background Art

[0002] Connected vehicle cooperative formation driving has broad application prospects in intelligent transportation systems, which can improve road utilization rate, reduce traffic congestion and accident rates. With the increasing communication requirements between vehicles, vehicle formation and cooperative communication have become research hotspots.

[0003] In vehicle formation, due to the limitations of formation, spacing and speed, direct communication is sometimes difficult to achieve. At the same time, in complex scenarios, direct communication between vehicles may be blocked or signal attenuation may occur. Therefore, it is necessary to select appropriate relay points for information forwarding. Selecting appropriate relay points requires considering various factors, such as signal strength, channel capacity, network topology, vehicle position, etc. Existing relay point selection technologies have problems such as signal interference, spectrum competition and security, and need to be further improved and optimized. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a relay point selection method for connected vehicle cooperative formation driving in a complex communication environment to solve the problems in the prior art that in the connected vehicle cooperative formation driving scheme, when vehicle communication forwards information through relay points, there are signal interference and spectrum competition, resulting in unreliable vehicle communication.

[0005] Embodiments of the present invention provide a relay point selection method for connected vehicle cooperative formation driving in a complex communication environment, including:

[0006] When the communication quality of the vehicle cooperative formation decreases or the communication is interrupted, use the analytic hierarchy process to score and rank several communication indicators of all connected vehicles in the current scenario of the vehicle cooperative formation except the formation vehicles;

[0007] Rank all connected vehicles from high to low according to the scores, and select the top three as relay point vehicles;

[0008] Arbitrarily select at least one from the 3 relay point vehicles for permutation and combination to obtain 7 relay communication links;

[0009] Obtain the communication quality levels of all relay communication links through an evaluation function;

[0010] If the communication quality level of at least one of the 7 relay communication links meets the preset conditions, integrate the corresponding relay communication link into the vehicle networking architecture; otherwise, select the cloud platform as the communication relay point;

[0011] Among them, several communication metrics include: penetration, multipath propagation, latency, propagation distance, and bandwidth.

[0012] Optionally, the judgment conditions for the decline or interruption of the communication quality of the vehicle platoon include:

[0013] The cloud platform evaluates the communication quality of the vehicle platoon based on the vehicle communication signal strength, communication delay, and packet loss rate of the vehicle platoon:

[0014] When any connected vehicle in the vehicle platoon meets any one of the following conditions: the vehicle communication signal strength drops to a preset signal strength value, the communication delay reaches a preset delay value, and the packet loss rate reaches a preset ratio;

[0015] Judge that the current communication quality of the vehicle platoon has declined; and / or,

[0016] The cloud platform obtains the operating environment of all connected vehicles in the vehicle platoon based on the real-time positions, real-time driving speeds, and real-time driving directions of all connected vehicles in the vehicle platoon, in combination with the map;

[0017] Judge whether there is signal shielding for the vehicle platoon according to the operating environment;

[0018] If there is signal shielding, it is judged that the communication of the vehicle platoon is interrupted.

[0019] Optionally, use the analytic hierarchy process to score and rank several communication metrics of all connected vehicles other than the platoon vehicles in the current scenario of the vehicle platoon, including:

[0020] Take all connected vehicles as the target layer;

[0021] Take several communication metrics as the criterion conditions of the criterion layer, score all connected vehicles, and rank them according to the scores from high to low;

[0022] Rank all connected vehicles from high to low according to the scores, and select the top three as the relay point vehicles, including:

[0023] Take the top three connected vehicles in the ranking as the output of the measure layer to obtain the relay point vehicles.

[0024] Optionally, using the analytic hierarchy process to score and rank several communication metrics of all connected vehicles other than the platoon vehicles in the current scenario of the vehicle platoon, also includes:

[0025] Based on the current communication requirements, construct a judgment matrix according to the importance between communication metrics pairwise;

[0026] Calculate the weight values corresponding to all communication metrics according to the judgment matrix, which are used to represent the importance of each communication metric;

[0027] Construct a parameter matrix according to the communication index parameters of all connected vehicles;

[0028] Normalize the similar elements of the parameter matrix according to the communication index type to obtain the index reference values of the communication index parameters corresponding to each connected vehicle;

[0029] Sum the products of all the index reference values of the same connected vehicle multiplied by the corresponding communication index weight values to obtain the score of the corresponding connected vehicle;

[0030] Among them, if the communication index is a negative index, then take the negative value of the corresponding index reference value.

[0031] Optionally, it further includes:

[0032] Judge the communication interruption type of vehicle cooperative formation;

[0033] If the communication interruption is caused by the dynamic movement of the connected vehicle, then construct a judgment matrix with penetration as the most important index;

[0034] If the communication interruption is caused by signal shielding, then construct a judgment matrix with bandwidth as the most important index.

[0035] Optionally, after constructing the judgment matrix based on several communication indexes, it further includes:

[0036] Conduct a consistency test on the judgment matrix;

[0037] If the consistency test is passed, proceed to the next calculation;

[0038] If the consistency test is not passed, adjust the corresponding element values until the consistency test is passed.

[0039] Optionally, obtain the communication quality levels of all relay communication links through an evaluation function, including:

[0040] Take communication delay, packet loss rate, and bandwidth as independent variables, and set evaluation functions from four evaluation directions respectively;

[0041] Judge the communication quality level of the corresponding relay communication link as excellent, good, or poor according to the results of the evaluation function;

[0042] Among them, the evaluation functions in the four evaluation directions include: real-time control information transmission quality evaluation function, vehicle information and entertainment information transmission quality evaluation function, vehicle remote detection and diagnosis information transmission quality evaluation function, and intelligent transportation information transmission quality evaluation function.

[0043] Optionally, the real-time control information transmission quality evaluation function includes:

[0044]

[0045] The vehicle information and entertainment information transmission quality evaluation function includes:

[0046]

[0047] The vehicle remote detection and diagnosis information transmission quality evaluation function includes:

[0048]

[0049] The intelligent transportation information transmission quality evaluation function includes:

[0050]

[0051] Wherein, D represents the time delay during information transmission between platooning vehicles, B represents the bandwidth during information transmission between platooning vehicles, and P represents the packet loss rate during information transmission between platooning vehicles.

[0052] Optionally, the preset conditions include:

[0053] Judge whether there is a difference in the communication quality levels corresponding to the four evaluation functions;

[0054] If there is, select the cloud platform as the communication relay point;

[0055] If not, continue to judge whether there are two or more excellences in the communication quality levels corresponding to the four evaluation functions;

[0056] If so, integrate the corresponding relay communication link into the vehicle networking architecture; otherwise, select the cloud platform as the communication relay point.

[0057] Advantages of the present invention:

[0058] 1. The embodiment of the present invention provides a relay point selection method for cooperative platooning of networked vehicles in a complex communication environment. By using the analytic hierarchy process algorithm and introducing relay point selection criteria, factors such as transmission distance, time delay, bandwidth, and multipath propagation ability are comprehensively considered to achieve more accurate and efficient relay point selection.

[0059] 2. The embodiment of the present invention provides a vehicle platooning communication quality evaluation function with time delay, bandwidth, and packet loss rate as independent variables, and constructs a selection mechanism for vehicle-to-vehicle / vehicle-to-cloud relay communication in a complex environment.

[0060] 3. The embodiment of the present invention uses the combination formula and the analytic hierarchy process to implement relay point selection, enabling the data between networked vehicles to be continuously transmitted, thereby ensuring communication quality and stability. Description of the Drawings

[0061] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the drawings:

[0062] Figure 1 shows a flowchart of a relay point selection method for cooperative formation driving of connected vehicles in a complex communication environment according to an embodiment of the present invention;

[0063] Figure 2 shows a hierarchical structure diagram for obtaining an optimal relay point vehicle according to an embodiment of the present invention;

[0064] Figure 3 shows a hierarchical structure diagram for obtaining the communication quality level of a relay point vehicle according to an embodiment of the present invention;

[0065] Figure 4 shows a schematic diagram of blocked formation communication in a vehicle-to-everything (V2X) network according to an embodiment of the present invention;

[0066] Figure 5 shows a schematic diagram of an optimal relay point communication link according to an embodiment of the present invention. Detailed implementation manners

[0067] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0068] As Figure 1 shown, an embodiment of the present invention provides a relay point selection method for cooperative formation driving of connected vehicles in a complex communication environment. When the communication quality of vehicle cooperative formation deteriorates or communication is interrupted, the following steps are performed:

[0069] Step S10: Use the analytic hierarchy process to score and rank several communication metrics of all connected vehicles except the formation vehicles in the current scenario of vehicle cooperative formation.

[0070] Step S20: Rank all connected vehicles in the vehicle cooperative formation from high to low according to the scores, and select the top three as relay point vehicles.

[0071] Step S30: Arbitrarily select at least one from the 3 relay point vehicles for permutation and combination to obtain 7 relay communication links.

[0072] Step S40: Obtain the communication quality levels of all relay communication links through an evaluation function.

[0073] Determine whether the communication quality level of at least one of the seven relay communication links meets a preset condition.

[0074] If so, execute step S501 to integrate the corresponding relay communication link into the vehicle networking architecture.

[0075] Otherwise, execute step S502 to select the cloud platform as the communication relay point.

[0076] Among them, several communication metrics include: penetration, multipath propagation ability, latency, propagation distance, and bandwidth.

[0077] In this embodiment, first, it is necessary to detect the communication status of the vehicle networking formation through the cloud platform. When it is detected that the vehicle networking communication between the formation vehicles is interfered, the cloud platform obtains the position information, speed, and direction of the vehicles and analyzes the operating environment of the vehicles. Then, based on the environment where the vehicle is located, the cloud considers factors such as transmission distance, latency, bandwidth, multipath propagation ability, and penetration, and assigns different weights to each index. The cloud scores different relay point vehicles through the Analytic Hierarchy Process (AHP), and preferentially selects three relay point vehicles m1, m2, m3, and uses the combination formula to obtain seven communication links: m1, m2, m3, m1 - m2, m1 - m3, m2 - m3, m1 - m2 - m3, and then uses the Analytic Hierarchy Process to evaluate the communication quality of the relay link. Then, the transmission quality of different types of information of the formation vehicles under relay communication is evaluated through an evaluation function. If the relay communication link with the highest score meets the requirements of the vehicle - to - vehicle / vehicle - to - cloud selection mechanism in a complex environment, then this relay communication link is integrated into the vehicle networking, otherwise, the cloud platform is selected as the communication relay point.

[0078] The embodiment of the present invention provides a method for selecting a relay point for cooperative formation driving of networked vehicles in a complex communication environment. By adopting the Analytic Hierarchy Algorithm and introducing a relay point selection criterion, factors such as transmission distance, latency, bandwidth, and multipath propagation ability are comprehensively considered to achieve more accurate and efficient relay point selection.

[0079] As an optional implementation manner, the judgment conditions for the communication quality of vehicle cooperative formation to decline or communication to be interrupted include:

[0080] The cloud platform evaluates the communication quality of the vehicle cooperative formation according to the vehicle communication signal strength, communication delay, and packet loss rate of the vehicle cooperative formation:

[0081] When any one of the networked vehicles in the vehicle cooperative formation meets any of the following conditions: the vehicle communication signal strength drops to a preset signal strength value, the communication delay reaches a preset delay value, and the packet loss rate reaches a preset ratio;

[0082] It is determined that the current communication quality of the vehicle cooperative formation has declined; and / or,

[0083] The cloud platform obtains the operating environment of all connected vehicles in the vehicle cooperative formation based on the real-time positions, real-time driving speeds, and real-time driving directions of all connected vehicles in the vehicle cooperative formation, and combines with the map.

[0084] Judge whether there is signal shielding in the vehicle cooperative formation according to the operating environment.

[0085] If there is signal shielding, it is judged that the communication of the vehicle cooperative formation is interrupted.

[0086] As an optional implementation manner, step S10 includes:

[0087] Take all connected vehicles as the target layer;

[0088] Take several communication metrics as the criterion conditions of the criterion layer, score all connected vehicles, and sort them according to the scores from high to low;

[0089] Sort all connected vehicles in the vehicle cooperative formation from high to low according to the scores, and select the top three as the relay point vehicles, including:

[0090] Take the top three connected vehicles in the sorting as the output of the measure layer to obtain the relay point vehicles.

[0091] As Figure 2 shown, in the two cases of vehicle-to-vehicle communication interruption caused by the dynamic movement of vehicles and vehicle-to-vehicle communication interruption caused by signal shielding in the vehicle formation, different weights are assigned to the five relay point evaluation metrics of transmission distance, delay, bandwidth, multipath propagation ability, and penetration. The 1-9 scale is used to represent the relative importance degree between factors. The analytic hierarchy process is used to calculate the scores of each candidate relay point vehicle. The higher the score of the relay point vehicle, the higher the priority.

[0092] In the specific implementation manner, determine the hierarchical structure. Take selecting the optimal relay point vehicle as the target layer of the hierarchical structure, take transmission distance, delay, bandwidth, multipath propagation ability, and penetration as the criterion layer in the hierarchical structure, and take the selectable relay point vehicle m j around the formation as the measure layer of the hierarchical structure.

[0093] Respectively take the criterion layer metrics of transmission distance, delay, bandwidth, multipath propagation ability, and penetration as the measurement factors to construct a judgment matrix of relative importance between each other, and calculate the weight corresponding to each communication metric. According to the parameters corresponding to the 5 types of communication metrics of the relay point vehicle m j in the measure layer, construct a comparison matrix.

[0094] Combine the weights corresponding to each communication metric in the criterion layer with the communication metric parameters of the vehicles in the measure layer to obtain the scores of the connected vehicles.

[0095] As an alternative implementation, step S10 further includes:

[0096] Based on the current communication requirements, construct a judgment matrix according to the importance between pairwise communication metrics;

[0097] Calculate the weight value corresponding to each communication metric according to the judgment matrix, which is used to represent the importance of each communication metric;

[0098] Construct a parameter matrix according to the communication metric parameters of all connected vehicles;

[0099] Normalize the elements of the same type in the parameter matrix according to the communication metric type to obtain the index reference value of the communication metric parameters corresponding to each connected vehicle;

[0100] Sum the products of all index reference values of the same connected vehicle multiplied by the corresponding communication metric weight values to obtain the score of the corresponding connected vehicle;

[0101] Wherein, if the communication metric is a negative index, the corresponding index reference value is negated.

[0102] In this embodiment, there are 5 communication metrics, and a 5×5 judgment matrix is constructed, where each element is the relative importance between pairwise communication metrics. The root method is used to calculate the weight vector of the judgment matrix. First, calculate the product of each row and then take the nth root to obtain an n-dimensional vector, realizing dimensionality reduction. The calculation formula is as follows:

[0103]

[0104] The subscript i is used for the element belonging to the i-th communication metric type, n represents the vector dimension, n = 5, and a iq represents the element in the i-th row and q-th column in matrix A. Assuming the first row is the transmission distance, a 1q is the q-th element in the first row, representing the relative importance degree of the transmission distance with respect to all communication metrics. is a 1×5 matrix, that is, a 5-dimensional vector.

[0105] Normalize the weight vector to convert it into the form of the ratio of an individual to the whole. The calculation formula is as follows:

[0106]

[0107] Wherein, ∑w i = 1, and the larger the value of w i , the higher the importance degree of the corresponding communication metric.

[0108] According to the various communication index parameters of connected vehicles, a parameter matrix is constructed. After normalizing the communication index parameters of the same type, if the communication index is a negative index, the value obtained by normalization is negated. The score calculation formula for connected vehicles is:

[0109] Score(m j )=∑w i b ji

[0110]

[0111]

[0112] In the formula, taking b 11 ~b 15 as an example, it represents the normalized values of 5 communication index parameters corresponding to the vehicle numbered m1, multiplied by the corresponding weights and then summed to obtain the score of vehicle m1.

[0113] In a specific embodiment, as Figure 3 shown, the relay communication link also uses the analytic hierarchy process to perform scoring and ranking first, and preferentially evaluates the communication quality level of the relay communication links ranked higher:

[0114] Analyze the relay point link selection scheme. Taking the optimal link k p as the target layer, transmission distance, delay, bandwidth, multipath propagation ability, and penetration ability as the criterion layer, and the relay point link selection scheme as the measure layer, construct an analytic hierarchy model, and use the AHP algorithm to evaluate the communication quality of each link. Respectively taking the criterion layer indicators of transmission distance, delay, bandwidth, multipath propagation ability, and penetration ability as the measurement factors, construct 5 weight matrices for the relay point links in the measure layer, and calculate the matrix weight vector and the total score to evaluate the communication quality of each relay link. The higher the score of the relay vehicle link, the higher the priority of the link.

[0115] As an optional implementation method, it further includes:

[0116] Judge the communication interruption type of vehicle cooperative formation;

[0117] If the communication interruption is caused by the dynamic movement of connected vehicles, then use penetration ability as the most important indicator to construct a judgment matrix;

[0118] If the communication interruption is caused by signal shielding, then use bandwidth as the most important indicator to construct a judgment matrix.

[0119] In this embodiment, in combination with the weight table of evaluation indicators for formation vehicles in different environments, the relative importance of the selectable relay points in the criterion layer is compared pairwise, and judgment matrices are constructed respectively for the case of vehicle formation vehicle-to-vehicle communication interruption, as shown in Table 1 and Table 2.

[0120] Table 1 Judgment matrix for communication interruption caused by the dynamic movement of vehicles

[0121] Transmission distance Delay Bandwidth Multipath propagation ability Penetration ability Transmission distance 1 3 5 7 9 Delay 0.33 1 3 5 7 Bandwidth 0.2 0.33 1 3 5 Multipath propagation ability 0.14 0.2 0.33 1 3 Penetration ability 0.11 0.14 0.2 0.33 1

[0122] Table 2 Judgment matrix for communication interruption caused by signal shielding

[0123] Penetration ability Multipath propagation ability Delay Transmission distance Bandwidth Penetration ability 1 3 5 7 9 Multipath propagation ability 0.33 1 3 5 7 Delay 0.2 0.33 1 3 5 Propagation distance 0.14 0.2 0.33 1 3 Bandwidth 0.11 0.14 0.2 0.33 1

[0124] The judgment matrix A is:

[0125]

[0126] As an alternative implementation, after constructing the judgment matrix based on several communication indicators, it further includes:

[0127] Conduct a consistency test on the judgment matrix;

[0128] If the consistency test is passed, proceed to the next calculation;

[0129] If the consistency test is not passed, adjust the corresponding element values until the consistency test is passed.

[0130] Taking the judgment matrix in Table 1 as an example, for transmission distance for delay for bandwidth for multipath propagation ability for penetration The normalized weight of transmission distance w1 = 0.51, the normalized weight of delay w2 = 0.26, the normalized weight of bandwidth w3 = 0.12, the normalized weight of multipath propagation ability w4 = 0.097, and the normalized weight of penetration w5 = 0.03.

[0131] Combining the judgment matrix A with the normalized weight vector W = [w1, w2, w3, w4, w5], solve for the maximum eigenvalue of the weight matrix, and its formula is:

[0132]

[0133] where n is the number of dimensions, and in this embodiment n = 5; AW is the judgment matrix × the normalized weight, and then the cumulative value by row.

[0134] AW = [2.4 1.5 0.75 0.35 0.18]

[0135] λmax = 5.27

[0136]

[0137] When the matrix is of order 5, the random consistency index R.I. is 1.12. Calculate C.R. to judge whether its consistency passes. The calculation formula is as follows:

[0138] C.R. = (C.I.) / (R.I.) = 0.0607

[0139] C.R. < 0.1 indicates that the consistency degree of the judgment matrix A is considered to be within the allowable range. At this time, the eigenvector of A can be used to calculate the weight vector.

[0140] As an alternative implementation, step S40 includes:

[0141] Taking the communication delay, packet loss rate, and bandwidth as independent variables, and setting evaluation functions from four evaluation directions respectively;

[0142] Judging the communication quality level of the corresponding relay communication link as excellent, good, or poor according to the results of the evaluation functions;

[0143] Among them, the evaluation functions for the four evaluation directions include: real-time control information transmission quality evaluation function, vehicle information and entertainment information transmission quality evaluation function, vehicle remote detection and diagnosis information transmission quality evaluation function, and intelligent transportation information transmission quality evaluation function.

[0144] As an alternative implementation, the real-time control information transmission quality evaluation function includes:

[0145]

[0146] The vehicle information and entertainment information transmission quality evaluation function includes:

[0147]

[0148] The vehicle remote detection and diagnosis information transmission quality evaluation function includes:

[0149]

[0150] The intelligent transportation information transmission quality evaluation function includes:

[0151]

[0152] Among them, D represents the time delay during information transmission between platooning vehicles, B represents the bandwidth during information transmission between platooning vehicles, and P represents the packet loss rate during information transmission between platooning vehicles. f(D) is an evaluation function for information time delay, f(B) is an evaluation function for information bandwidth, f(P) is an evaluation function for information packet loss rate, and F(D, B, P) is an evaluation function for information transmission quality.

[0153] As an optional implementation manner, the preset conditions include:

[0154] Judge whether there are differences in the communication quality levels corresponding to the four evaluation functions;

[0155] If there are, select the cloud platform as the communication relay point;

[0156] If not, continue to judge whether there are two or more excellences in the communication quality levels corresponding to the four evaluation functions;

[0157] If so, integrate the corresponding relay communication link into the vehicle networking architecture; otherwise, select the cloud platform as the communication relay point.

[0158] Table 3 Judgment conditions for excellent information transmission quality

[0159]

[0160] If the values of the evaluation functions simultaneously satisfy the values of f(D), f(B), f(P), and F(D, B, P) in Table 3, it is determined that the transmission quality of this type of information under the relay point communication link is excellent.

[0161] Table 4 Judgment conditions for poor information transmission quality

[0162]

[0163] If any one of the values of the evaluation functions satisfies the values of f(D), f(B), f(P), and F(D, B, P) in Table 4, it is determined that the transmission quality of this type of information under the relay point communication link is poor.

[0164] In a specific implementation manner, when a communication interruption occurs as Figure 4 shown, through the above implementation manner, a communication relay link as Figure 5 shown is obtained.

[0165] This embodiment provides a vehicle platooning communication quality evaluation function with time delay, bandwidth, and packet loss rate as independent variables, and constructs a selection mechanism for vehicle-to-vehicle / vehicle-to-cloud relay communication in a complex environment. In addition, the relay point selection is realized by using the combination formula and the analytic hierarchy process, so that the data between connected vehicles can be kept transmitted, thus ensuring the communication quality and stability.

[0166] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment, characterized in that: include: When the communication quality of the vehicle cooperative formation decreases or the communication is interrupted, the analytic hierarchy process is used to score and sort several communication indicators of all connected vehicles except the formation vehicles in the current scene of the vehicle cooperative formation; Sort all the networked vehicles by score from high to low, and select the top three vehicles as relay point vehicles; At least one of the three relay point vehicles is randomly selected for permutation and combination to obtain seven relay communication links; Obtaining the communication quality level of all the relay communication links through an evaluation function; If the communication quality level of at least one of the seven relay communication links meets the preset conditions, the corresponding relay communication link is integrated into the vehicle networking architecture; Otherwise, choose the cloud platform as the communication relay point; Among them, some of the communication indicators include: penetration, multipath propagation, delay, propagation distance and bandwidth; The communication quality levels of all the relay communication links are obtained through an evaluation function, including: The communication delay, packet loss rate and bandwidth are used as independent variables, and the evaluation functions are set from four evaluation directions respectively; Determining, according to the result of the evaluation function, whether the communication quality level corresponding to the relay communication link is excellent, good or poor; Among them, the evaluation functions of the four evaluation directions include: real-time control information transmission quality evaluation function, vehicle information and entertainment information transmission quality evaluation function, vehicle remote detection and diagnosis information transmission quality evaluation function and intelligent traffic information transmission quality evaluation function; The preset conditions include: Determine whether there is a difference in the communication quality levels corresponding to the four evaluation functions; If it exists, the cloud platform is selected as the communication relay point; If not, continue to determine whether two or more communication quality levels corresponding to the four evaluation functions are excellent; If so, the corresponding relay communication link is integrated into the Internet of Vehicles architecture; otherwise, the cloud platform is selected as the communication relay point.

2. The method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment according to claim 1, characterized in that: The judgment conditions for the degradation of communication quality or interruption of communication of the vehicle cooperative formation include: The cloud platform evaluates the communication quality of the vehicle cooperative formation according to the vehicle communication signal strength, communication delay and packet loss rate of the vehicle cooperative formation: When any of the networked vehicles in the vehicle cooperative formation meets any of the following conditions: the vehicle communication signal strength drops to a preset signal strength value, the communication delay reaches a preset delay value, and the packet loss rate reaches a preset ratio; Determining that the current communication quality of the vehicle cooperative formation has decreased; and / or, The cloud platform obtains the operating environment of all the connected vehicles in the vehicle cooperative formation according to the real-time position, real-time driving speed and real-time driving direction of all the connected vehicles in the vehicle cooperative formation in combination with the map; Determining whether there is signal shielding in the vehicle cooperative formation according to the operating environment; If there is signal shielding, it is determined that the communication of the vehicle cooperative formation is interrupted.

3. The method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment according to claim 2, characterized in that: The analytic hierarchy process is used to score and rank several communication indicators of all connected vehicles except the platoon vehicles in the current scenario of the vehicle cooperative platoon, including: Taking all the networked vehicles as the target layer; Using the plurality of communication indicators as criteria of the criteria layer, scoring all the networked vehicles, and sorting them according to the scores; All the networked vehicles are sorted from high to low by score, and the top three are selected as relay point vehicles, including: The top three connected vehicles are used as the output of the measure layer to obtain the relay point vehicles.

4. The method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment according to claim 3, characterized in that: The analytic hierarchy process is used to score and sort several communication indicators of all connected vehicles except the platoon vehicles in the current scenario of the vehicle cooperative platoon, including: Based on the current communication needs, a judgment matrix is ​​constructed according to the importance between the communication indicators; Calculate the weight values ​​of all communication indicators one by one according to the judgment matrix to characterize the importance of each communication indicator; Constructing a parameter matrix according to the communication index parameters of all the networked vehicles; Normalizing the same type of elements of the parameter matrix according to the communication index type to obtain an index reference value of the communication index parameter corresponding to each of the networked vehicles; Multiply all the index reference values ​​of the same connected vehicle by the corresponding communication index weight value and then sum them up to obtain a score corresponding to the connected vehicle; If the communication indicator is a negative indicator, the corresponding indicator reference value is negatively processed.

5. The method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment according to claim 4, characterized in that: Also includes: Determining a communication interruption type of the vehicle cooperative formation; If the communication interruption is caused by the dynamic movement of the connected vehicle, the penetration is used as the most important indicator to construct the judgment matrix; If the communication interruption is caused by signal shielding, the bandwidth is taken as the most important indicator to construct the judgment matrix.

6. The method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment according to claim 4, characterized in that: After constructing the judgment matrix based on the communication indicators, the method further includes: Performing a consistency check on the judgment matrix; If the consistency check is passed, the next step of calculation will be entered; If the consistency check fails, the corresponding element value is adjusted until the consistency check passes.

7. The method for selecting relay points for cooperative platooning of networked vehicles in a complex communication environment according to claim 1, characterized in that: The real-time control information transmission quality evaluation function includes: The vehicle information and entertainment information transmission quality evaluation function includes: The vehicle remote detection and diagnosis information transmission quality evaluation function includes: The intelligent traffic information transmission quality evaluation function includes: Among them, D represents the delay of information transmission between platoon vehicles, B represents the bandwidth of information transmission between platoon vehicles, and P represents the packet loss rate of information transmission between platoon vehicles.

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