Vehicle Internet of Things Broadcast Relay Selection Method, System, Device and Storage Medium

Abstract

The present invention discloses a method, system, device and storage medium for vehicle networking broadcast relay selection. The method includes: respectively constructing a candidate relay vehicle set with security guarantee through a relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle; constructing a candidate relay vehicle set with reliability guarantee through a reliability evaluation function based on the candidate relay vehicle set with security guarantee; constructing a candidate relay vehicle set with high-efficiency guarantee through a propagation efficiency evaluation function based on the candidate relay vehicle set with reliability guarantee; respectively calculating the broadcast waiting duration corresponding to each candidate broadcast relay vehicle through a waiting time formula; and determining the next-hop broadcast relay vehicle according to the broadcast waiting duration. The present invention obtains multiple candidate broadcast relay vehicles through a security evaluation function, a reliability evaluation function and a propagation efficiency evaluation function, and then realizes safe, reliable and efficient vehicle networking broadcast relay selection according to the broadcast waiting duration and the broadcast response result.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle networking, and particularly to a method, system, device and storage medium for vehicle networking broadcast relay selection. Background Art

[0002] Vehicle networking is a typical application of the Internet of Things and an important part of modern intelligent transportation. In vehicle networking, broadcasting is a good way to disseminate messages, especially effective for the rapid dissemination of emergency messages (such as road collapses and vehicle rear-end collisions). Vehicles usually collect basic safety messages broadcast by other vehicles within their transmission range of each other to learn about the surrounding road conditions and vehicle information. Vehicles then determine which vehicles are suitable as relays. Based on different relay selection methods, current multi-hop broadcast strategies can be divided into two categories, namely sender-based and receiver-based strategies. The main difference between these two strategies lies in whether the next-hop relay is determined by the current relay vehicle.

[0003] The sender-based strategy features high real-time performance, which is very beneficial for the dissemination of emergency messages. In this approach, the current relay vehicle selects certain nodes as candidate relay nodes in a centralized manner according to several metrics, such as distance, link quality, etc. If a candidate relay vehicle does not receive the same emergency message during the waiting period, it will be upgraded to the current relay vehicle and immediately broadcast the received emergency message. Otherwise, the candidate relay vehicle will cancel the broadcast plan to avoid broadcast storms. However, candidate relays may be very close to each other, so it is easy to send broadcast messages simultaneously, resulting in transmission conflicts and even broadcast storms.

[0004] The above content is only used to assist in understanding the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of the present invention is to provide a method, system, device and storage medium for vehicle networking broadcast relay selection, aiming to solve the technical problem of how to achieve safe, reliable and efficient vehicle networking broadcast relay selection.

[0006] To achieve the above objective, the present invention provides a method for vehicle networking broadcast relay selection, the vehicle networking broadcast relay selection method comprising:

[0007] Determining relay information corresponding to each communication vehicle on the current road according to the current broadcast relay vehicle;

[0008] Constructing a set of candidate relay vehicles with security guarantees through a relay vehicle safety evaluation function according to the relay information corresponding to each communication vehicle;

[0009] The set of candidate relay vehicles based on the security guarantee constructs a set of candidate relay vehicles with reliability guarantee through a reliability evaluation function;

[0010] The set of candidate relay vehicles with reliability guarantee constructs a set of candidate relay vehicles with high-efficiency guarantee through a propagation efficiency evaluation function, and the set of candidate relay vehicles with high-efficiency guarantee includes multiple candidate broadcast relay vehicles;

[0011] Calculate the broadcast waiting duration corresponding to each candidate broadcast relay vehicle respectively through the waiting time formula;

[0012] Determine the next-hop broadcast relay vehicle according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle.

[0013] Optionally, the step of constructing a set of candidate relay vehicles with security guarantee respectively through a relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle includes:

[0014] Determine the historical credibility, self-reported credibility and third-party credibility corresponding to each communication vehicle according to the relay information corresponding to each communication vehicle;

[0015] Calculate the security evaluation function value corresponding to each communication vehicle respectively through the relay vehicle security evaluation function according to the historical credibility, the self-reported credibility and the third-party credibility;

[0016] The relay vehicle security evaluation function is:

[0017] S i =αS history +βS self +γS other

[0018] α + β + γ = 1

[0019]

[0020] When there is no untrustworthy record for any communication vehicle:

[0021] S history =S self =S n =1

[0022] When there is an untrustworthy record for any communication vehicle:

[0023]

[0024] In the formula, S i is the security evaluation function value of vehicle i, S history is the historical credibility, S self is the self-reported credibility, Sother Let \(T\) be the third - party credibility, \(\alpha\) be the historical credibility weight, \(\beta\) be the self - reported credibility weight, \(\gamma\) be the third - party credibility weight, \(x\) be the number of days after the candidate relay vehicle has an untrustworthy record, and \(S\) n be the credibility of a single vehicle \(n\) with respect to vehicle \(i\);

[0025] Select a plurality of candidate relay vehicles from a plurality of communication vehicles according to the safety evaluation function value;

[0026] Form a candidate relay vehicle set for safety guarantee based on the plurality of candidate relay vehicles.

[0027] Optionally, the step of constructing a candidate relay vehicle set for reliability guarantee through a reliability evaluation function based on the candidate relay vehicle set for safety guarantee includes:

[0028] Calculate the reliability evaluation function values corresponding to each candidate relay vehicle in the candidate relay vehicle set for safety guarantee respectively through the reliability evaluation function;

[0029] Determine a candidate relay vehicle set for reliability guarantee according to the reliability evaluation function value, and the candidate relay vehicle set for reliability guarantee includes a plurality of reliability candidate relay vehicles.

[0030] Optionally, the reliability evaluation function is:

[0031] Z i =a×R i +b×U i

[0032]

[0033]

[0034] In the formula, \(Z\) i is the reliability evaluation function value of vehicle \(i\), \(R\) i is the signal - to - noise ratio function of vehicle \(i\), \(a\) is the signal - to - noise ratio weight, \(SNR\) i is the signal - to - noise ratio between vehicle \(i\) and the current broadcast relay vehicle, \(SNR\) max is the theoretical maximum signal - to - noise ratio in the vehicle - to - everything environment, \(U\) i is the historical success rate of vehicle \(i\), \(b\) is the historical success rate weight, is the number of historical successful communications between vehicle \(i\) and the current broadcast relay vehicle, is the total number of historical communications between vehicle \(i\) and the current broadcast relay vehicle.

[0035] Optionally, the step of constructing a candidate relay vehicle set for high - efficiency guarantee through a propagation efficiency evaluation function based on the candidate relay vehicle set for reliability guarantee includes:

[0036] Calculate the propagation efficiency evaluation function values corresponding to multiple reliability candidate relay vehicles in the candidate relay vehicle set for reliability guarantee respectively through the propagation efficiency evaluation function;

[0037] Determine the candidate relay vehicle set for high-efficiency guarantee according to the propagation efficiency evaluation function values.

[0038] Optionally, the propagation efficiency evaluation function is:

[0039] X i = p × D i + q × E i

[0040]

[0041]

[0042] In the formula, X i is the propagation efficiency evaluation function value of vehicle i, D i is the broadcast distance factor of vehicle i, p is the weight of the broadcast distance factor, d i is the distance between vehicle i and the current broadcast relay vehicle, D max is the maximum one-hop communication range of the vehicle, E i is the vehicle density factor, q is the weight of the vehicle density factor, N i is the total number of vehicles that vehicle i can receive periodic vehicle messages, is the theoretical maximum value of the total number of vehicles within the one-hop communication range of the vehicle under the condition of safe distance.

[0043] Optionally, the step of calculating the broadcast waiting duration corresponding to each candidate broadcast relay vehicle respectively through the waiting time formula includes:

[0044] Determine the propagation efficiency evaluation function values corresponding to each candidate broadcast relay vehicle respectively, and perform priority sorting on multiple candidate broadcast relay vehicles according to the propagation efficiency evaluation function values;

[0045] Determine the time interval rules corresponding to each candidate broadcast relay vehicle according to the priority sorting result, and the time interval rules include a high-priority strategy and a low-priority strategy;

[0046] Calculate the broadcast waiting duration corresponding to each candidate broadcast relay vehicle respectively through the waiting time formula according to the time interval rules;

[0047] The waiting time formula is:

[0048]

[0049] In the formula, Ti is the broadcast waiting duration for vehicle i, P i is the priority level of candidate broadcast relay vehicle i, Q 3 is the total number of vehicles within the set of candidate relay vehicles for high-efficiency guarantee, J big is the first time interval, J small is the second time interval, Ω is the basic time interval, and ε is the increment of the basic time interval.

[0050] In addition, to achieve the above object, the present invention also proposes a vehicle-to-everything (V2X) broadcast relay selection system, and the V2X broadcast relay selection system includes:

[0051] A determination module, configured to respectively determine the relay information corresponding to each communication vehicle on the current road according to the current broadcast relay vehicle;

[0052] A calculation module, configured to respectively construct a set of candidate relay vehicles for security guarantee through a relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle;

[0053] The calculation module is further configured to construct a set of candidate relay vehicles for reliability guarantee through a reliability evaluation function based on the set of candidate relay vehicles for security guarantee;

[0054] The calculation module is further configured to construct a set of candidate relay vehicles for high-efficiency guarantee through a propagation efficiency evaluation function based on the set of candidate relay vehicles for reliability guarantee, and the set of candidate relay vehicles for high-efficiency guarantee includes multiple candidate broadcast relay vehicles;

[0055] The calculation module is further configured to respectively calculate the broadcast waiting duration corresponding to each candidate broadcast relay vehicle through a waiting time formula;

[0056] A selection module, configured to determine the next-hop broadcast relay vehicle according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle.

[0057] In addition, to achieve the above object, the present invention also proposes a V2X broadcast relay selection device, and the device includes: a memory, a processor, and a V2X broadcast relay selection program stored on the memory and executable on the processor, and the V2X broadcast relay selection program is configured to implement the steps of the V2X broadcast relay selection method as described above.

[0058] In addition, to achieve the above object, the present invention also proposes a storage medium, and a V2X broadcast relay selection program is stored on the storage medium, and when the V2X broadcast relay selection program is executed by a processor, the steps of the V2X broadcast relay selection method as described above are implemented.

[0059] The present invention first determines the relay information corresponding to each communication vehicle on the current road according to the current broadcast relay vehicle, then constructs a candidate relay vehicle set for security guarantee through a relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle, then constructs a candidate relay vehicle set for reliability guarantee through a reliability evaluation function based on the candidate relay vehicle set for security guarantee, and constructs a candidate relay vehicle set for high-efficiency guarantee through a propagation efficiency evaluation function based on the candidate relay vehicle set for reliability guarantee. The candidate relay vehicle set for high-efficiency guarantee includes multiple candidate broadcast relay vehicles. Finally, the broadcast waiting duration corresponding to each candidate broadcast relay vehicle is calculated through a waiting time formula, and the next-hop broadcast relay vehicle is determined according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle. The present invention obtains multiple candidate broadcast relay vehicles through a security evaluation function, a reliability evaluation function, and a propagation efficiency evaluation function, and then realizes safe, reliable, and efficient vehicle-to-everything (V2X) broadcast relay selection according to the broadcast waiting duration and the broadcast response result. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 is a schematic structural diagram of a vehicle-to-everything (V2X) broadcast relay selection device in a hardware operating environment related to the solution of an embodiment of the present invention;

[0061] Figure 2 is a schematic flowchart of a first embodiment of the vehicle-to-everything (V2X) broadcast relay selection method of the present invention;

[0062] Figure 3 is a schematic diagram of a vehicle-to-everything (V2X) message broadcast scenario in a first embodiment of the vehicle-to-everything (V2X) broadcast relay selection method of the present invention;

[0063] Figure 4 is a schematic diagram of the allocation of time intervals in a first embodiment of the vehicle-to-everything (V2X) broadcast relay selection method of the present invention;

[0064] Figure 5 is a schematic block diagram of a first embodiment of the vehicle-to-everything (V2X) broadcast relay selection system of the present invention.

[0065] The implementation, functional features, and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0066] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0067] Refer to Figure 1 , Figure 1 is a schematic structural diagram of a vehicle-to-everything (V2X) broadcast relay selection device in a hardware operating environment related to the solution of an embodiment of the present invention.

[0068] As Figure 1As shown in the figure, the vehicle networking broadcast relay selection device may include: a processor 1001, such as a Central Processing Unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to implement the connection and communication between these components. The user interface 1003 may include a display screen (Display) and an input unit such as a keyboard (Keyboard). Optionally, the user interface 1003 may further include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed Random Access Memory (RAM) or a stable Non-Volatile Memory (NVM), such as a disk memory. Optionally, the memory 1005 may also be a storage system independent of the aforementioned processor 1001.

[0069] Those skilled in the art can understand that Figure 1 the structure shown in the figure does not constitute a limitation on the vehicle networking broadcast relay selection device, and it may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0070] As Figure 1 shown, the memory 1005, as a storage medium, may include an operating system, a network communication module, a user interface module, and a vehicle networking broadcast relay selection program.

[0071] In Figure 1 the vehicle networking broadcast relay selection device shown in the figure, the network interface 1004 is mainly used for data communication with a network server; the user interface 1003 is mainly used for data interaction with a user; the processor 1001 and the memory 1005 in the vehicle networking broadcast relay selection device of the present invention may be provided in the vehicle networking broadcast relay selection device. The vehicle networking broadcast relay selection device calls the vehicle networking broadcast relay selection program stored in the memory 1005 through the processor 1001 and executes the vehicle networking broadcast relay selection method provided by the embodiments of the present invention.

[0072] The embodiments of the present invention provide a vehicle networking broadcast relay selection method. Referring to Figure 2 , Figure 2 it is a schematic flowchart of the first embodiment of the vehicle networking broadcast relay selection method of the present invention.

[0073] In this embodiment, the vehicle networking broadcast relay selection method includes the following steps:

[0074] Step S10: Determine the relay information corresponding to each communication vehicle on the current road based on the current broadcast relay vehicle.

[0075] It is easy to understand that the execution subject of this embodiment can be a vehicle - to - everything (V2X) broadcast relay selection system with functions such as data processing, network communication, and program operation, or other computer devices with similar functions. This embodiment does not impose any restrictions.

[0076] It should be noted that, referring to Figure 3 , Figure 3 is a schematic diagram of the V2X message broadcast scenario in the first embodiment of the V2X broadcast relay selection method of the present invention. The current broadcast relay vehicle is the relay vehicle that sends broadcast information instructions on the current road.

[0077] The communication vehicle is a vehicle that can receive the broadcast information instructions sent by the current broadcast relay vehicle. The relay information includes historical credibility, self - reported credibility, and third - party credibility. The historical credibility refers to the credibility of the candidate relay vehicle stored by the current broadcast relay vehicle. The self - reported credibility refers to the credibility provided by the candidate relay vehicle itself. The third - party credibility refers to the average value of the credibility of the candidate relay vehicle sent by N other vehicles communicating with the current broadcast relay vehicle.

[0078] Step S20: Construct a set of candidate relay vehicles for security guarantee through the relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle.

[0079] Further, calculate the security evaluation function values corresponding to each communication vehicle through the relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle, select multiple candidate relay vehicles from multiple communication vehicles according to the security evaluation function values, and form a set of candidate relay vehicles for security guarantee based on the multiple candidate relay vehicles.

[0080] Further, the processing method of calculating the security evaluation function values corresponding to each communication vehicle through the relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle is to determine the historical credibility, self - reported credibility, and third - party credibility corresponding to each communication vehicle according to the relay information corresponding to each communication vehicle; calculate the security evaluation function values corresponding to each communication vehicle through the relay vehicle security evaluation function according to the historical credibility, self - reported credibility, and third - party credibility;

[0081] The relay vehicle security evaluation function is:

[0082] S i =αS history +βS self +γS other

[0083] α + β + γ = 1

[0084]

[0085] When there is no untrusted record in any communication vehicle:

[0086] S history = S self = S n = 1

[0087] When there is an untrusted record in any communication vehicle:

[0088]

[0089] Wherein, S i is the safety evaluation function value of vehicle i, S history is the historical credibility, which refers to the credibility of the candidate relay vehicle stored in the current relay vehicle, S self is the self-reported credibility, which refers to the credibility of the candidate relay vehicle provided by itself, S other is the third-party credibility, which refers to the average value of the credibility of the candidate relay vehicle sent by the other N vehicles communicating with the current relay vehicle. α is the weight of the historical credibility, β is the weight of the self-reported credibility, γ is the weight of the third-party credibility, S n is the credibility of a single vehicle n for vehicle i, which belongs to the third-party credibility. x is the number of days after the candidate relay vehicle has an untrusted record. When x = 0, that is, on the same day, the credibility is 0. When x is large enough, the credibility approaches 1.

[0090] It should also be noted that it is recommended that α = 0.5, β = γ = 0.25. When S history and S other do not exist, their values are 0.

[0091] In this embodiment, the communication vehicles can be sorted from large to small according to the safety evaluation function values corresponding to each communication vehicle, and then Q 1 vehicles (for example, 15 vehicles) are selected in order from large to small according to the sorting result to form a candidate relay vehicle set Set 1 for safety guarantee.

[0092] It should be understood that the number of Q 1 can be user-defined, and this embodiment does not limit it.

[0093] Step S30: Based on the candidate relay vehicle set for safety guarantee, construct a candidate relay vehicle set for reliability guarantee through a reliability evaluation function.

[0094] Further, the reliability evaluation function values corresponding to each candidate relay vehicle in the candidate relay vehicle set for safety guarantee are calculated respectively, and the candidate relay vehicle set for reliability guarantee is determined according to the reliability evaluation function values. The candidate relay vehicle set for reliability guarantee includes multiple candidate relay vehicles for reliability.

[0095] In a specific implementation, the reliability evaluation function is:

[0096] Z i = a × R i + b × U i

[0097]

[0098]

[0099] In the formula, Z i is the reliability evaluation function value of vehicle i, R i is the signal-to-noise ratio function of vehicle i, a is the signal-to-noise ratio weight, SNR i is the signal-to-noise ratio between vehicle i and the current broadcast relay vehicle, SNR max is the theoretical maximum signal-to-noise ratio in the vehicle networking environment, U i is the historical success rate of vehicle i, b is the historical success rate weight, is the number of historical successful communications between vehicle i and the current broadcast relay vehicle, is the total number of historical communications between vehicle i and the current broadcast relay vehicle.

[0100] It should also be understood that a + b = 1. It is recommended that a = 0.6 and b = 0.4.

[0101] In this embodiment, each candidate relay vehicle is sorted from large to small according to the corresponding reliability evaluation function value, and then according to the sorting result, Q 2 vehicles (for example, 10 vehicles) are sequentially selected from the candidate relay vehicle set Set 1 for safety guarantee from large to small to form the candidate relay vehicle set Set 2 for reliability guarantee.

[0102] Q 2 The quantity can be user-defined, and this embodiment does not impose any restrictions.

[0103] Step S40: Based on the candidate relay vehicle set for reliability guarantee, a candidate relay vehicle set for high-efficiency guarantee is constructed through a propagation efficiency evaluation function. The candidate relay vehicle set for high-efficiency guarantee includes multiple candidate broadcast relay vehicles.

[0104] Calculate the propagation efficiency evaluation function values corresponding to multiple reliability candidate relay vehicles in the candidate relay vehicle set for reliability guarantee respectively through the propagation efficiency evaluation function, and determine the candidate relay vehicle set for high-efficiency guarantee according to the propagation efficiency evaluation function values.

[0105] It should also be noted that the propagation efficiency is judged according to the broadcast distance factor and the vehicle density factor. The farther the broadcast distance, the higher the propagation efficiency. The greater the vehicle density, the more vehicles receive the message, and the higher the effectiveness of continued broadcasting.

[0106] The propagation efficiency evaluation function is:

[0107] X i = p×D i + q×E i

[0108]

[0109]

[0110] In the formula, X i is the propagation efficiency evaluation function value of vehicle i, D i is the broadcast distance factor of vehicle i, p is the weight of the broadcast distance factor, d i is the distance between vehicle i and the current broadcast relay vehicle, D max is the one-hop maximum communication range of the vehicle, E i is the vehicle density factor, q is the weight of the vehicle density factor, N i is the total number of vehicles that vehicle i can receive periodic vehicle messages, is the theoretical maximum value of the total number of vehicles within the one-hop communication range of the vehicle under the condition of safe distance.

[0111] It should be understood that p + q = 1, and it is recommended that a = 0.5, b = 0.5.

[0112] In this embodiment, sort the reliability candidate relay vehicles from largest to smallest according to the propagation efficiency evaluation function values corresponding to multiple reliability candidate relay vehicles in the candidate relay vehicle set for reliability guarantee, and then select Q 3 vehicles (for example, 6 vehicles) in order from largest to smallest from the candidate relay vehicle set Set2 for reliability guarantee to form a candidate relay set for high-efficiency guarantee, that is, the candidate relay vehicle set Set 3 for high-efficiency guarantee.

[0113] Step S50: Calculate the broadcast waiting duration corresponding to each candidate broadcast relay vehicle respectively through the waiting time formula.

[0114] Determine the time interval rules corresponding to each candidate broadcast relay vehicle respectively, and calculate the broadcast waiting duration corresponding to each candidate broadcast relay vehicle respectively according to the time interval rules through the waiting time formula.

[0115] Furthermore, the processing method for determining the time interval rules corresponding to each candidate broadcast relay vehicle respectively is to determine the propagation efficiency evaluation function values corresponding to each candidate broadcast relay vehicle respectively, and perform priority sorting on multiple candidate broadcast relay vehicles according to the propagation efficiency evaluation function values; determine the time interval rules corresponding to each candidate broadcast relay vehicle according to the priority sorting result, and the time interval rules include a high-priority strategy and a low-priority strategy.

[0116] It should also be understood that the first time interval formula corresponds to the high-priority strategy, and the second time interval formula corresponds to the low-priority strategy.

[0117] In specific implementation, after each candidate broadcast relay vehicle node receives the broadcast message of the current broadcast relay vehicle, each waits for a certain time to make a response, that is, to broadcast the message or abandon broadcasting the message. If the waiting time arrives but the message is not broadcast by other vehicles, then broadcast the message, otherwise abandon broadcasting. In order to eliminate transmission conflicts, the waiting times of each vehicle must be different, and there must be a basic interval for the waiting times of adjacent candidate broadcast relay vehicles, which includes 4 parts: the propagation delay between two relays, the idle channel evaluation time T CCA , the switching time T phy for antenna transmission and reception, and the transmission time T trans of the message. This basic time interval Ω can be expressed as:

[0118]

[0119] D max is the maximum one-hop communication distance of the vehicle, usually taken as 300m, C is the speed of light, T phy is 2μs, T CCA is 8μs, here, T trans is set to the transmission time of the message to be broadcast.

[0120] It should also be noted that the time interval rules corresponding to each candidate broadcast relay vehicle are respectively used for different situations.

[0121] Second time interval formula:

[0122] J small = Ω

[0123] First time interval formula:

[0124] J bi g = Ω + ε

[0125] Where ε is the increment of the basic time interval Ω, for example, ε = 0.2Ω.

[0126] It should also be noted that with reference to Figure 4 , Figure 4 FIG. is a schematic diagram of the time interval allocation of the first embodiment of the vehicle networking broadcast relay selection method of the present invention. The broadcast waiting duration corresponding to each candidate broadcast relay vehicle depends on its priority. It is necessary to determine half of the number corresponding to the set of candidate relay vehicles that need to be efficiently guaranteed. When the rank value of the candidate broadcast relay vehicle is less than or equal to half of the number corresponding to the set of candidate relay vehicles that need to be efficiently guaranteed, the broadcast waiting duration corresponding to the candidate broadcast relay vehicle is calculated by the first time interval formula; when the rank value of the candidate broadcast relay vehicle is greater than half of the number corresponding to the set of candidate relay vehicles that need to be efficiently guaranteed, the broadcast waiting duration corresponding to the candidate broadcast relay vehicle is calculated by the combination of the first time interval formula and the second time interval formula.

[0127] It should be understood that the Q 3 candidate broadcast relay vehicles are sorted according to the propagation efficiency evaluation function values of each candidate broadcast relay vehicle. The larger the propagation efficiency evaluation function value, the higher the ranking, that is, the higher the priority. The priority is set to the first level (highest priority) P i = 1, the second level P i = 2, the third level P i = 3, ….

[0128] The waiting time formula is:

[0129]

[0130] J small = Ω

[0131] J big = Ω + ε

[0132] In the formula, T i is the broadcast waiting duration of vehicle i, P i is the priority level of candidate broadcast relay vehicle i, Q 3 is the total number of vehicles in the set of candidate relay vehicles that need to be efficiently guaranteed, J big is the first time interval, J small is the second time interval, Ω is the basic time interval, and v is the increment of the basic time interval.

[0133] represents the ceiling of half of the members in Set 3.

[0134] In a specific implementation, for the first half of the members (high-priority members) in Set 3, the first time interval formula is adopted. This is beneficial to reducing broadcast conflicts and improving reliability. For the second half of the members (low-priority members) in Set 3, the second time interval formula is adopted. This is beneficial to reducing waiting time and improving propagation efficiency.

[0135] For example, the number of members Q in Set 3 3 = 6, J small = 0.1 second, J big = 0.12 second, then the actual waiting times of each vehicle are: T 1 = 0 second, T 2 = 0.12 second, T 3 = 0.24 second, T 4 = 0.34 second, T 5 = 0.44 second, T 6 = 0.54 second.

[0136] Step S60: Determine the next-hop broadcast relay vehicle according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle.

[0137] When the current broadcast relay vehicle sends the broadcast information to each candidate broadcast relay vehicle, determine the next-hop broadcast relay vehicle based on the broadcast waiting duration and the broadcast response result corresponding to each candidate broadcast relay vehicle.

[0138] The broadcast response result can be understood as that the candidate broadcast relay vehicle plays or cancels the waiting when the broadcast waiting duration arrives.

[0139] In this embodiment, the current broadcast relay vehicle sends instructions to each candidate broadcast relay vehicle, and the instructions include the broadcast waiting duration and the broadcast information of each candidate broadcast relay vehicle. Each candidate broadcast relay vehicle makes a response according to the allocated broadcast waiting duration. That is, if the same broadcast message is received from a neighbor vehicle before the broadcast waiting duration arrives, the waiting is cancelled, that is, giving up becoming a broadcast relay. If the same broadcast message is not received from a neighbor vehicle when the broadcast waiting duration arrives, it becomes a broadcast relay by itself, that is, the next-hop broadcast relay vehicle, and immediately broadcasts the previously received broadcast message.

[0140] In this embodiment, first, the relay information corresponding to each communication vehicle on the current road is determined according to the current broadcast relay vehicle. Then, based on the relay information corresponding to each communication vehicle, a candidate relay vehicle set for security guarantee is constructed through a relay vehicle security evaluation function. After that, based on the candidate relay vehicle set for security guarantee, a candidate relay vehicle set for reliability guarantee is constructed through a reliability evaluation function. And based on the candidate relay vehicle set for reliability guarantee, a candidate relay vehicle set for high-efficiency guarantee is constructed through a propagation efficiency evaluation function. The candidate relay vehicle set for high-efficiency guarantee includes multiple candidate broadcast relay vehicles. Finally, the broadcast waiting duration corresponding to each candidate broadcast relay vehicle is calculated respectively through a waiting time formula, and the next-hop broadcast relay vehicle is determined according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle. Compared with the traditional method in the prior art, it is difficult to find a suitable weight, resulting in a certain performance not meeting the requirements. For example, the selected relay node may have high reliability and high propagation efficiency, but its security cannot be guaranteed. Moreover, the traditional vehicle relay method based on the sender is prone to transmission conflicts and even broadcast storms. In this embodiment, the relay vehicles are screened in order of importance. First, the nodes with high security are screened out, then the nodes with high reliability are screened out within this range, and then the nodes with high propagation efficiency are screened out on this basis. It is achieved by sorting the candidate nodes and setting different waiting times, and there is a sufficient time interval between different waiting times to avoid transmission conflicts.

[0141] Refer to Figure 5 , Figure 5 is the structural block diagram of the first embodiment of the vehicle networking broadcast relay selection system of the present invention.

[0142] As Figure 5 shown, the vehicle networking broadcast relay selection system proposed in the embodiment of the present invention includes:

[0143] A determination module 5001, configured to determine the relay information corresponding to each communication vehicle on the current road according to the current broadcast relay vehicle;

[0144] A calculation module 5002, configured to construct a candidate relay vehicle set for security guarantee through a relay vehicle security evaluation function according to the relay information corresponding to each communication vehicle;

[0145] The calculation module 5002 is further configured to construct a candidate relay vehicle set for reliability guarantee through a reliability evaluation function based on the candidate relay vehicle set for security guarantee;

[0146] The calculation module 5002 is further configured to construct a candidate relay vehicle set for high-efficiency guarantee through a propagation efficiency evaluation function based on the candidate relay vehicle set for reliability guarantee. The candidate relay vehicle set for high-efficiency guarantee includes multiple candidate broadcast relay vehicles;

[0147] The calculation module 5002 is further configured to calculate the broadcast waiting duration corresponding to each candidate broadcast relay vehicle respectively through a waiting time formula;

[0148] The selection module 5003 is configured to determine the next-hop broadcast relay vehicle according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle.

[0149] In this embodiment, first, the relay information corresponding to each communication vehicle on the current road is determined respectively according to the current broadcast relay vehicle, then, based on the relay information corresponding to each communication vehicle, a candidate relay vehicle set with security guarantee is constructed through a relay vehicle security evaluation function, then, based on the candidate relay vehicle set with security guarantee, a candidate relay vehicle set with reliability guarantee is constructed through a reliability evaluation function, and based on the candidate relay vehicle set with reliability guarantee, a candidate relay vehicle set with high-efficiency guarantee is constructed through a propagation efficiency evaluation function. The candidate relay vehicle set with high-efficiency guarantee includes multiple candidate broadcast relay vehicles. Finally, the broadcast waiting duration corresponding to each candidate broadcast relay vehicle is calculated respectively through the waiting time formula, and the next-hop broadcast relay vehicle is determined according to the broadcast waiting duration corresponding to each candidate broadcast relay vehicle. Compared with the prior art, it is difficult to find a suitable weight in the traditional method, resulting in a certain performance not meeting the requirements. For example, the selected relay node may have high reliability and high propagation efficiency, but the security cannot be guaranteed, and the traditional vehicle relay method based on the sender is prone to transmission conflicts and even broadcast storms. However, in this embodiment, the relay vehicles are screened in order of importance. First, the nodes with high security are screened out, then the nodes with high reliability are screened out within this range, and then the nodes with high propagation efficiency are screened out on this basis. It is achieved by sorting the candidate nodes and setting different waiting times, and there is a sufficient time interval between different waiting times to avoid transmission conflicts.

[0150] For other embodiments or specific implementation manners of the vehicle-to-everything (V2X) broadcast relay selection system of the present invention, reference may be made to the above method embodiments, which will not be elaborated herein.

[0151] It should be noted that, in this article, the terms "include", "comprise" or any other variant thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or system including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the process, method, article or system including the element.

[0152] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0153] Through the description of the above embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as a read-only memory / random access memory, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of the present invention.

[0154] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A method for selecting a broadcast relay in a vehicle network, characterized in that: The vehicle networking broadcast relay selection method comprises the following steps: Determine the relay information corresponding to each communication vehicle on the current road according to the current broadcast relay vehicle; According to the relay information corresponding to each communication vehicle, a set of candidate relay vehicles with safety assurance is constructed through the relay vehicle safety evaluation function; Based on the candidate relay vehicle set with safety assurance, a candidate relay vehicle set with reliability assurance is constructed through a reliability evaluation function; Based on the reliability-guaranteed candidate relay vehicle set, a high-efficiency-guaranteed candidate relay vehicle set is constructed through a propagation efficiency evaluation function, wherein the high-efficiency-guaranteed candidate relay vehicle set includes a plurality of candidate broadcast relay vehicles; The broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated by the waiting time formula; The next-hop broadcast relay vehicle is determined according to the broadcast waiting time corresponding to each candidate broadcast relay vehicle.

2. The method according to claim 1, characterized in that The step of constructing a set of candidate relay vehicles with safety assurance through a relay vehicle safety evaluation function according to the relay information corresponding to each communication vehicle comprises: Determine the historical credibility, self-reported credibility and third-party credibility of each communication vehicle according to the relay information corresponding to each communication vehicle; Calculate the safety evaluation function value corresponding to each communication vehicle respectively through the relay vehicle safety evaluation function according to the historical credibility, the self-reported credibility and the third-party credibility; The relay vehicle safety evaluation function is: S i =αS history +βS self +γS other α+β+γ=1 When there is no untrusted record in any of the communicating vehicles: S history =S self =S n =1 When an untrustworthy record appears in any communication vehicle: In the formula, S i is the safety evaluation function value of vehicle i, S history is the historical credibility, S self is the self-reported credibility, S other is the third-party credibility, α is the historical credibility weight, β is the self-reported credibility weight, γ is the third-party credibility weight, x is the number of days after the candidate relay vehicle has an untrustworthy record, S n is the credibility of a single vehicle n to vehicle i; Selecting a plurality of candidate relay vehicles from a plurality of communication vehicles according to the safety evaluation function value; A safety-guaranteed candidate relay vehicle set is formed based on a plurality of candidate relay vehicles.

3. The method according to claim 1 or 2, characterized in that The step of constructing a reliability-guaranteed candidate relay vehicle set based on the safety-guaranteed candidate relay vehicle set by using a reliability evaluation function comprises: Calculate the reliability evaluation function value corresponding to each candidate relay vehicle in the candidate relay vehicle set for safety assurance by using the reliability evaluation function; A set of candidate relay vehicles with reliability assurance is determined according to the reliability evaluation function value, and the set of candidate relay vehicles with reliability assurance includes a plurality of reliability candidate relay vehicles.

4. The method according to claim 3, characterized in that The reliability evaluation function is: WITH i =a×R i +b×U i In the formula, Z i is the reliability evaluation function value of vehicle i, R i is the signal-to-noise ratio function of vehicle i, a is the signal-to-noise ratio weight, SNR i is the signal-to-noise ratio between vehicle i and the current broadcast relay vehicle, SNR max is the theoretical maximum signal-to-noise ratio in the Internet of Vehicles environment, U i is the historical success rate of vehicle i, b is the weight of the historical success rate, is the number of historical successful communications between vehicle i and the current broadcast relay vehicle, is the total number of historical communications between vehicle i and the current broadcast relay vehicle.

5. The method according to claim 4, characterized in that The step of constructing a high-efficiency guaranteed candidate relay vehicle set based on the reliability-guaranteed candidate relay vehicle set by using a propagation efficiency evaluation function comprises: Calculate the propagation efficiency evaluation function values ​​corresponding to the multiple reliability candidate relay vehicles in the candidate relay vehicle set of the reliability guarantee respectively by using the propagation efficiency evaluation function; A set of candidate relay vehicles with high efficiency guarantee is determined according to the transmission efficiency evaluation function value.

6. The method according to claim 5, characterized in that The propagation efficiency evaluation function is: X i =p×D i +q×E i Where, X i is the transmission efficiency evaluation function value of vehicle i, D i is the broadcast distance factor of vehicle i, p is the broadcast distance factor weight, d i is the distance between vehicle i and the current broadcast relay vehicle, D max is the maximum communication range of one hop of the vehicle, E i is the vehicle density factor, q is the vehicle density factor weight, N i is the total number of vehicles from which vehicle i can receive periodic vehicle messages, It is the theoretical maximum number of vehicles within one-hop communication range under safe distance conditions.

7. The method according to claim 6, characterized in that The step of respectively calculating the broadcast waiting time corresponding to each candidate broadcast relay vehicle by using the waiting time formula comprises: Determining the propagation efficiency evaluation function value corresponding to each candidate broadcast relay vehicle respectively, and prioritizing the plurality of candidate broadcast relay vehicles according to the propagation efficiency evaluation function value; Determine the time interval rule corresponding to each candidate broadcast relay vehicle according to the priority sorting result, wherein the time interval rule includes a high priority strategy and a low priority strategy; According to the time interval rule, the broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated by the waiting time formula; The waiting time formula is: J small =Oh J big =Ω+ε Where, T i is the broadcast waiting time of vehicle i, P i is the priority level of candidate broadcast relay vehicle i, Q3 is the total number of vehicles in the candidate relay vehicle set with high efficiency guarantee, J big is the first time interval, J small is the second time interval, Ω is the basic time interval, and ε is the increment of the basic time interval.

8. A vehicle networking broadcast relay selection system, characterized in that: The vehicle networking broadcast relay selection system includes: A determination module, used to determine the relay information corresponding to each communication vehicle on the current road according to the current broadcast relay vehicle; A calculation module, used to construct a candidate relay vehicle set with safety assurance according to the relay information corresponding to each communication vehicle through a relay vehicle safety evaluation function; The calculation module is further used to construct a set of candidate relay vehicles with reliability assurance based on the set of candidate relay vehicles with safety assurance through a reliability evaluation function; The calculation module is further used to construct a high-efficiency guaranteed candidate relay vehicle set based on the reliability-guaranteed candidate relay vehicle set through a propagation efficiency evaluation function, wherein the high-efficiency guaranteed candidate relay vehicle set includes a plurality of candidate broadcast relay vehicles; The calculation module is further used to calculate the broadcast waiting time corresponding to each candidate broadcast relay vehicle by using a waiting time formula; The selection module is used to determine the next-hop broadcast relay vehicle according to the broadcast waiting time corresponding to each candidate broadcast relay vehicle.

9. A vehicle networking broadcast relay selection device, characterized in that: The device includes: a memory, a processor, and a vehicle network broadcast relay selection program stored in the memory and executable on the processor, wherein the vehicle network broadcast relay selection program is configured to implement the steps of the vehicle network broadcast relay selection method as described in any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium stores a vehicle networking broadcast relay selection program, and when the vehicle networking broadcast relay selection program is executed by the processor, the steps of the vehicle networking broadcast relay selection method as described in any one of claims 1 to 7 are implemented.

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