交通路口场景下基于802.11p的车队通信性能分析模型

编队策略作为无人驾驶的关键技术之一已经受到广泛的研究与实际的测试了.车队经过红绿灯管制的交通路口场景时,会受到红绿灯时间、队内(外)间距、速度和前进方向等参数的影响,此时因为车队通信网络复杂多变,所以难以维持车队行驶的稳定性,因此可能会进一步造成车队中采用802.11p协议通信的车辆不能在规定的时延限制内接收到完整的重...

Performance Analysis Model of 802.11 p Based Platooning Communication at Traffic Intersection

As one of the key technologies of automated driving,platooning strategy has been extensively studied and tested in practice.When platoons pass through the traffic intersection controlled by traffic light,kinetic parameters such as traffic light time,intra/inter-platoon spacing,speed,and moving direction are severely affected.At this time,since the platooning communication connectivity network is complex and variable,the driving stability of platoons is difficult to maintain,thus resulting in that the vehicles in platoons that communicate through 802.11p protocols cannot receive the complete important information within the specified delay limit,which finally leads to road safety issues.To solve this problem,considering the Enhanced Distributed Channel Access(EDCA)mechanism of the 802.11p protocol,which supports data of 4 transmission priorities to access channel,a novel communication performance analysis model for automated driving platoons under traffic intersection scenario is proposed.First,we build a connectivity network of vehicular communication at the traffic intersection and obtain the network communication performance through constructing the platoon moving model.Then,the classic Markov model that describes the 802.11p EDCA mechanism is transformed into a z-domain linear model by utilizing the method of probability generating function,and the platooning communication delay and packet delivery ratio(PDR)analysis model is deduced according to the priority differences of the 4 access categories.Finally,iterative method is used to calculate the platooning communication delay.The simulation results verify the accuracy of the analysis model,and it can be found that when passing through the intersection,the communication delay of platoons is lower than the 100ms specified by the 802.11p protocols and the packet delivery ratio is higher than 0.95,which ensures the timeliness and completeness of the platoon communication.