Internet of vehicles broadcast relay selection method, system and device and storage medium

Abstract

The invention discloses an Internet of Vehicles broadcast relay selection method, system and device, and a storage medium. The method comprises the following steps: according to relay information corresponding to each communication vehicle, constructing a safety-guaranteed candidate relay vehicle set through a relay vehicle safety evaluation function; constructing a reliability-guaranteed candidate relay vehicle set through a reliability evaluation function based on the safety-guaranteed candidate relay vehicle set; based on the reliability-guaranteed candidate relay vehicle set, constructing a high-efficiency-guaranteed candidate relay vehicle set through a propagation efficiency evaluation function; respectively calculating broadcast waiting duration corresponding to each candidate broadcast relay vehicle through a waiting time formula; and determining a next hop broadcast relay vehicle according to the broadcast waiting duration. According to the method, the plurality of candidate broadcast relay vehicles are obtained through the safety evaluation function, the reliability evaluation function and the propagation efficiency evaluation function, and then safe, reliable and efficient Internet of Vehicles broadcast relay selection is realized according to the broadcast waiting duration and the broadcast reaction result.

Description

Technical Field

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

[0002] The Internet of Vehicles is a typical application of the Internet of Things and an important part of modern intelligent transportation. In the Internet of Vehicles, broadcasting is a good way to spread messages, especially for the rapid spread of emergency messages (such as road collapse and vehicle rear-end collisions). Vehicles usually learn about the surrounding road conditions and vehicle information by collecting basic safety messages broadcast by other vehicles within the transmission range of each other. Vehicles can then determine which vehicles are suitable as relays. Based on the different relay selection methods, the 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 is whether the next-hop relay is determined by the current relay vehicle.

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

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

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

[0006] To achieve the above object, the present invention provides a method for selecting a broadcast relay in an Internet of Vehicles, the method comprising:

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

[0008] 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;

[0009] 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;

[0010] 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;

[0011] The broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated by the waiting time formula;

[0012] The next-hop broadcast relay vehicle is determined according to the broadcast waiting time corresponding to each candidate broadcast relay vehicle.

[0013] Optionally, the step of constructing a set of candidate relay vehicles with safety assurance by using a relay vehicle safety evaluation function according to the relay information corresponding to each communication vehicle comprises:

[0014] 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;

[0015] 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;

[0016] The relay vehicle safety evaluation function is:

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

[0018] α+β+γ=1

[0019]

[0020] When there is no untrusted record in any of the communicating vehicles:

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

[0022] When an untrustworthy record appears in any communication vehicle:

[0023]

[0024] 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, Sother 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;

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

[0026] A safety-guaranteed candidate relay vehicle set is formed based on a plurality of candidate relay vehicles.

[0027] Optionally, the step of constructing a set of candidate relay vehicles with reliability assurance based on the set of candidate relay vehicles with safety assurance by using a reliability evaluation function comprises:

[0028] 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;

[0029] 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.

[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 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.

[0035] Optionally, 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:

[0036] 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;

[0037] A set of candidate relay vehicles with high efficiency guarantee is determined according to the transmission efficiency evaluation function value.

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

[0039] X i =p×D i +q×E i

[0040]

[0041]

[0042] 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.

[0043] Optionally, the step of calculating the broadcast waiting time corresponding to each candidate broadcast relay vehicle by using a waiting time formula includes:

[0044] 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;

[0045] 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;

[0046] According to the time interval rule, the broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated by the waiting time formula;

[0047] The waiting time formula is:

[0048]

[0049] Where, Ti is the broadcast waiting time 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 candidate relay vehicle set 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-mentioned purpose, the present invention also proposes a vehicle networking broadcast relay selection system, the vehicle networking broadcast relay selection system comprising:

[0051] 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;

[0052] 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;

[0053] 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;

[0054] 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;

[0055] 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;

[0056] 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.

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

[0058] In addition, to achieve the above-mentioned purpose, the present invention also proposes a storage medium, on which a vehicle network broadcast relay selection program is stored. When the vehicle network broadcast relay selection program is executed by a processor, the steps of the vehicle network broadcast relay selection method 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, and then constructs a candidate relay vehicle set with safety assurance through the relay vehicle safety evaluation function according to the relay information corresponding to each communication vehicle, and then constructs a candidate relay vehicle set with reliability assurance through the reliability evaluation function based on the candidate relay vehicle set with safety assurance, and constructs a candidate relay vehicle set with high efficiency assurance through the propagation efficiency evaluation function based on the candidate relay vehicle set with reliability assurance. The candidate relay vehicle set with high efficiency assurance includes multiple candidate broadcast relay vehicles, and finally calculates the broadcast waiting time corresponding to each candidate broadcast relay vehicle through the waiting time formula, and determines the next-hop broadcast relay vehicle according to the broadcast waiting time corresponding to each candidate broadcast relay vehicle. The present invention obtains multiple candidate broadcast relay vehicles through the safety evaluation function, the reliability evaluation function and the propagation efficiency evaluation function, and then realizes safe, reliable and efficient vehicle network broadcast relay selection according to the broadcast waiting time and the broadcast response result. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a structural diagram of a vehicle networking broadcast relay selection device in a hardware operating environment involved in an embodiment of the present invention;

[0061] Figure 2 It is a flowchart of the first embodiment of the vehicle networking broadcast relay selection method of the present invention;

[0062] Figure 3 A schematic diagram of a vehicle networking message broadcasting scenario according to a first embodiment of a vehicle networking broadcast relay selection method of the present invention;

[0063] Figure 4 A schematic diagram of the allocation of time intervals of the first embodiment of the vehicle networking broadcast relay selection method of the present invention;

[0064] Figure 5 This is a structural block diagram of the first embodiment of the vehicle networking broadcast relay selection system of the present invention.

[0065] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[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] Reference Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle networking broadcast relay selection device in the hardware operating environment involved in the embodiment of the present invention.

[0068] like Figure 1As shown, 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 realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the optional user interface 1003 may also 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 (Wireless-Fidelity, Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM), or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk storage. The memory 1005 may also be a storage system independent of the aforementioned processor 1001.

[0069] Those skilled in the art will understand that Figure 1 The structure shown in does not constitute a limitation on the Internet of Vehicles broadcast relay selection device, and may include more or fewer components than shown in the figure, or a combination of certain components, or a different arrangement of components.

[0070] like Figure 1 As 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] exist Figure 1 In the shown vehicle networking broadcast relay selection device, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the vehicle networking broadcast relay selection device of the present invention can be set in the vehicle networking broadcast relay selection device, and 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 in the embodiment of the present invention.

[0072] The embodiment of the present invention provides a method for selecting a broadcast relay in a vehicle network, referring to Figure 2 , Figure 2 This is a flow chart 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 according to the current broadcast relay vehicle.

[0075] It is easy to understand that the execution subject of this embodiment can be a vehicle network broadcast relay selection system with functions such as data processing, network communication and program running, or it can be other computer equipment with similar functions, etc., and this embodiment is not limited.

[0076] It should be noted that the reference Figure 3 , Figure 3 This is a schematic diagram of the vehicle networking message broadcast scenario of the first embodiment of the vehicle networking broadcast relay selection method of the present invention. The current broadcast relay vehicle is the relay vehicle that sends the broadcast information instruction on the current road.

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

[0078] Step S20: constructing a set of candidate relay vehicles with safety assurance according to the relay information corresponding to each communication vehicle through a relay vehicle safety evaluation function.

[0079] Furthermore, according to the relay information corresponding to each communication vehicle, the safety evaluation function value corresponding to each communication vehicle is calculated by the relay vehicle safety evaluation function, and according to the safety evaluation function value, multiple candidate relay vehicles are selected from multiple communication vehicles, and a candidate relay vehicle set for safety assurance is formed based on the multiple candidate relay vehicles.

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

[0081] The relay vehicle safety 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 of the communicating vehicles:

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

[0087] When an untrustworthy record appears in any communication vehicle:

[0088]

[0089] In the formula, 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 vehicles stored by the current relay vehicle, S self is the self-reported credibility, which refers to the credibility provided by the candidate relay vehicle. other is the third-party credibility, which refers to the average credibility of the candidate relay vehicle sent by the other N vehicles communicating with the current relay vehicle, α is the historical credibility weight, β is the self-reported credibility weight, γ is the third-party credibility weight, S n is the credibility of a single vehicle n to vehicle i, which belongs to the third-party credibility. x is the number of days after the candidate relay vehicle has an untrustworthy record. x = 0, that is, on the same day, the credibility is 0. When x is large enough, the credibility is close to 1.

[0090] It should also be noted that it is recommended that α=0.5,β=γ=0.25,S history and S other If not present, its value is 0.

[0091] In this embodiment, the communication vehicles can be sorted from large to small according to the safety evaluation function values ​​corresponding to the communication vehicles, and then Q can be selected in order from large to small according to the sorting results. 1 A number of vehicles (for example, 15) constitute a candidate relay vehicle set Set 1 for safety assurance.

[0092] It should be understood that Q 1 The quantity can be customized by the user and is not limited in this embodiment.

[0093] Step S30: constructing 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.

[0094] Furthermore, the reliability evaluation function is used to calculate the reliability evaluation function value corresponding to each candidate relay vehicle in the candidate relay vehicle set for safety assurance, and the candidate relay vehicle set for reliability assurance is determined according to the reliability evaluation function value. The candidate relay vehicle set for reliability assurance includes multiple reliability candidate relay vehicles.

[0095] In the 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 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.

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

[0101] In this embodiment, the candidate relay vehicles are sorted from large to small according to the reliability evaluation function value corresponding to each candidate relay vehicle, and then Q is selected from the candidate relay vehicle set Set 1 with security assurance in order from large to small according to the sorting result. 2 A number of vehicles (for example, 10) constitute a candidate relay vehicle set Set 2 for reliability assurance.

[0102] Q 2 The quantity can be customized by the user and is not limited in this embodiment.

[0103] Step S40: constructing 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.

[0104] The propagation efficiency evaluation function is used to calculate the propagation efficiency evaluation function values ​​corresponding to multiple reliability candidate relay vehicles in the reliability guaranteed candidate relay vehicle set, and the high efficiency guaranteed candidate relay vehicle set is determined according to the propagation efficiency evaluation function values.

[0105] It should also be noted that the transmission efficiency is determined by the broadcast distance factor and the vehicle density factor. The longer the broadcast distance, the higher the transmission efficiency. The greater the vehicle density, the more vehicles will receive the message, and the more effective the continued broadcast will be.

[0106] The propagation efficiency evaluation function is:

[0107] X i =p×D i +q×E i

[0108]

[0109]

[0110] 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.

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

[0112] In this embodiment, the reliability candidate relay vehicles are sorted from large to small according to the transmission efficiency evaluation function values ​​corresponding to the multiple reliability candidate relay vehicles in the reliability guaranteed candidate relay vehicle set, and then Q is selected from the reliability guaranteed candidate relay vehicle set Set2 in order from large to small according to the sorting results. 3 A number of vehicles (for example, 6) constitute a high-efficiency guaranteed candidate relay set, namely, a high-efficiency guaranteed candidate relay vehicle set Set 3.

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

[0114] The time interval rules corresponding to each candidate broadcast relay vehicle are determined respectively, and the broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated respectively by using the waiting time formula according to the time interval rules.

[0115] Furthermore, the processing method for respectively determining the time interval rule corresponding to each candidate broadcast relay vehicle is to respectively determine the propagation efficiency evaluation function value corresponding to each candidate broadcast relay vehicle, and prioritize multiple 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 ranking result, and the time interval rule includes a high priority strategy and a low priority strategy.

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

[0117] In the specific implementation, after each candidate broadcast relay vehicle node receives the broadcast message of the current broadcast relay vehicle, it waits for a certain period of time to respond, that is, broadcast the message or give up broadcasting the message. If the waiting time is reached but no other vehicle broadcasts the message, the message is broadcast, otherwise the broadcast is abandoned. In order to eliminate transmission conflicts, the waiting time of each vehicle must be different, and the waiting time of adjacent candidate broadcast relay vehicles must have a basic interval, which includes 4 parts: the propagation delay between the two relays, the idle channel evaluation time T CCA , Antenna transmission and reception switching time T phy , message transmission time T trans The basic time interval Ω can be expressed as:

[0118]

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

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

[0121] The second time interval formula:

[0122] J small =Ω

[0123] First time interval formula:

[0124] J bi g=Ω+ε

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

[0126] It should also be noted that the reference Figure 4 , Figure 4 This is a schematic diagram of the allocation of time intervals for the first embodiment of the vehicle network broadcast relay selection method of the present invention. The broadcast waiting time corresponding to each candidate broadcast relay vehicle depends on its priority. It is necessary to determine half of the number of candidate relay vehicles corresponding to the set of high-efficiency guaranteed vehicles. When the level value of the candidate broadcast relay vehicle is less than or equal to half of the number of candidate relay vehicles corresponding to the set of high-efficiency guaranteed vehicles, the broadcast waiting time corresponding to the candidate broadcast relay vehicle is calculated by the first time interval formula; when the level value of the candidate broadcast relay vehicle is greater than half of the number of candidate relay vehicles corresponding to the set of high-efficiency guaranteed vehicles, the broadcast waiting time corresponding to the candidate broadcast relay vehicle is calculated by combining the first time interval formula and the second time interval formula.

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

[0128] The waiting time formula is:

[0129]

[0130] J small =Ω

[0131] J big =Ω+ε

[0132] Where, T i is the broadcast waiting time 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 candidate relay vehicle set 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 v is the increment of the basic time interval.

[0133] Indicates that half of the members in Set 3 are rounded up.

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

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

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

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

[0138] The broadcast reaction result can be understood as the candidate broadcast relay vehicle playing or canceling the waiting time when the broadcast waiting time is reached.

[0139] In this embodiment, the current broadcast relay vehicle sends instructions to each candidate broadcast relay vehicle, and the instructions include the broadcast waiting time and broadcast information of each candidate broadcast relay vehicle. Each candidate broadcast relay vehicle responds according to the allocated broadcast waiting time. That is, if the same broadcast message is received from a neighboring vehicle before the broadcast waiting time expires, the waiting is canceled, that is, the broadcast relay is abandoned. If the same broadcast message is not received from a neighboring vehicle when the broadcast waiting time expires, the candidate broadcast relay vehicle becomes a broadcast relay, that is, the next-hop broadcast relay vehicle, and immediately broadcasts the previously received broadcast message.

[0140] In this embodiment, firstly, the relay information corresponding to each communication vehicle on the current road is determined according to the current broadcast relay vehicle, and then the candidate relay vehicle set with safety guarantee is constructed through the relay vehicle safety evaluation function according to the relay information corresponding to each communication vehicle, and then the candidate relay vehicle set with reliability guarantee is constructed through the reliability evaluation function based on the candidate relay vehicle set with safety guarantee, and the candidate relay vehicle set with high efficiency guarantee is constructed through the transmission efficiency evaluation function based on the candidate relay vehicle set with reliability guarantee. The candidate relay vehicle set with high efficiency guarantee includes multiple candidate broadcast relay vehicles, and finally the broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated through the waiting time formula, and the next hop broadcast relay vehicle is determined according to the broadcast waiting time 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 nodes may have high reliability and high transmission efficiency, but their security cannot be guaranteed. The traditional vehicle relay method based on the sender is prone to transmission conflicts and even broadcast storms. The present embodiment screens the relay vehicles in order of importance, first screening out nodes with high security, then screening out nodes with high reliability within this range, and then screening out nodes with high transmission efficiency on this basis. This is achieved by sorting the candidate nodes and setting different waiting times, and there is enough time interval between different waiting times to avoid transmission conflicts.

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

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

[0143] Determination module 5001, used 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 is 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;

[0145] The calculation module 5002 is further used to construct a candidate relay vehicle set with reliability assurance through a reliability evaluation function based on the candidate relay vehicle set with safety assurance;

[0146] The calculation module 5002 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;

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

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

[0149] In this embodiment, firstly, the relay information corresponding to each communication vehicle on the current road is determined according to the current broadcast relay vehicle, and then the candidate relay vehicle set with safety guarantee is constructed through the relay vehicle safety evaluation function according to the relay information corresponding to each communication vehicle, and then the candidate relay vehicle set with reliability guarantee is constructed through the reliability evaluation function based on the candidate relay vehicle set with safety guarantee, and the candidate relay vehicle set with high efficiency guarantee is constructed through the transmission efficiency evaluation function based on the candidate relay vehicle set with reliability guarantee. The candidate relay vehicle set with high efficiency guarantee includes multiple candidate broadcast relay vehicles, and finally the broadcast waiting time corresponding to each candidate broadcast relay vehicle is calculated through the waiting time formula, and the next hop broadcast relay vehicle is determined according to the broadcast waiting time 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 nodes may have high reliability and high transmission efficiency, but their security cannot be guaranteed. The traditional vehicle relay method based on the sender is prone to transmission conflicts and even broadcast storms. The present embodiment screens the relay vehicles in order of importance, first screening out nodes with high security, then screening out nodes with high reliability within this range, and then screening out nodes with high transmission efficiency on this basis. This is achieved by sorting the candidate nodes and setting different waiting times, and there is enough time interval between different waiting times to avoid transmission conflicts.

[0150] Other embodiments or specific implementation methods of the vehicle networking broadcast relay selection system of the present invention can refer to the above-mentioned method embodiments and will not be repeated here.

[0151] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements 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 implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0154] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also 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, Ω3 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.

Images