Road Side Units(RSUs)are the essential component of vehicular communication for the objective of improving safety and mobility in the road transportation.RSUs are generally deployed at the roadside and more specifical...Road Side Units(RSUs)are the essential component of vehicular communication for the objective of improving safety and mobility in the road transportation.RSUs are generally deployed at the roadside and more specifically at the intersections in order to collect traffic information from the vehicles and disseminate alarms and messages in emergency situations to the neighborhood vehicles cooperating with the network.However,the development of a predominant RSUs placement algorithm for ensuring competent communication in VANETs is a challenging issue due to the hindrance of obstacles like water bodies,trees and buildings.In this paper,Ruppert’s Delaunay Triangulation Refinement Scheme(RDTRS)for optimal RSUs placement is proposed for accurately estimating the optimal number of RSUs that has the possibility of enhancing the area of coverage during data communication.This RDTRS is proposed by considering the maximum number of factors such as global coverage,intersection popularity,vehicle density and obstacles present in the map for optimal RSUs placement,which is considered as the core improvement over the existing RSUs optimal placement strategies.It is contributed for deploying requisite RSUs with essential transmission range for maximal coverage in the convex map such that each position of the map could be effectively covered by at least one RSU in the presence of obstacles.The simulation experiments of the proposed RDTRS are conducted with complex road traffic environments.The results of this proposed RDTRS confirmed its predominance in reducing the end-to-end delay by 21.32%,packet loss by 9.38%with improved packet delivery rate of 10.68%,compared to the benchmarked schemes.展开更多
Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need ...Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need for optimising the flow of vehicles at different intersections and reducing the waiting time is a critical challenge.Conventional traffic lights have been used to control traffic flow at different intersections and have been improved to become more efficient by using different algorithms,sensors and cameras.However,they also face some challenges,such as high-cost installation,operation,and maintenance issues.This paper develops a new system based on the Virtual Traffic Light(VTL)technology to improve traffic flow at different intersections and reduce the encountered loss of time and vehicles’travel time.Additionally,it reduces the costs of installation,maintenance and operation over various conventional traffic light systems.Consequently,the system proposes algorithms for traffic scheduling and lane identification by using vehicle ID,priority and time of arrival.To evaluate the system,four scenarios were presented where each scenario uses a different number of vehicles consisting of three types(emergency vehicles,public buses and private vehicles),each given a different priority.The proposed system is evaluated by integrating two simulators,namely,(OMNeT++)and(SUMO),and two frameworks,namely,(VEINS)and(INET)to prepare an appropriate working environment.the results prove that an improvement in the average travel time for several vehicles reaches 44.43%–49.76%compared with conventional traffic lights.Further,it is proven from the obtained results that the average waiting time for emergency vehicles is enhanced by 96.63%–97.63%,while the average waiting time for public buses is improved by 94.81%–97.23%.On the other hand,the waiting time for private vehicles‘improved by 87.14%to 89.71%’.展开更多
基于路侧感知的可变车道智能网联车路协同系统是将可变车道控制系统与智能网联车路协同系统深度融合组网,其原理是在路口部署路侧感知设备来检测目标路段车流量,在其上游路口部署可变车道交通控制系统,感知设备通过识别当前道路排队长...基于路侧感知的可变车道智能网联车路协同系统是将可变车道控制系统与智能网联车路协同系统深度融合组网,其原理是在路口部署路侧感知设备来检测目标路段车流量,在其上游路口部署可变车道交通控制系统,感知设备通过识别当前道路排队长度和平均车速综合判断当前该段道路是否拥堵,然后通过车路协同系统控制上游可变车道电子标牌允许行驶方向,从而控制目标道路的驶入车流量,达到缓解该路段的交通压力的目的。同时,在车路协同C-V2X(Cellular-Vehicle to Everything 蜂窝车联网)方面,根据可变车道控制的变化规律,制作多个对应的V2X MAP导入云控平台或RSU,然后系统各单元根据相关指令设置联动下发机制,保证车路协同系统信息(MAP、SPAT)和可变车道控制系统信息(电子标牌变更指令、信号机灯组变更指令)同步对应下发,保证车路协同系统V2I红绿灯场景实现及消息的准确性和稳定性。展开更多
车载自组网(vehicular ad?hoc networks,VANETs)已经成为智能交通(intelligent transportation system,ITS)的重要组成部分。在高速动态的城市环境下,为使道路车辆尽快选择到传输信息的最佳路线,提出一种基于Nakagami?m信道模型的V2X通...车载自组网(vehicular ad?hoc networks,VANETs)已经成为智能交通(intelligent transportation system,ITS)的重要组成部分。在高速动态的城市环境下,为使道路车辆尽快选择到传输信息的最佳路线,提出一种基于Nakagami?m信道模型的V2X通信协议(V2X communication protocol based on Nakagami?m channel model,VCNCM),来提高数据传输率(packet delivery ratio,PDR)和降低平均端到端延迟(average?end?to?end?delay,AE2ED)。本协议采用路边基础单元(road side units,RSUs)辅助通信系统来寻找最佳的通信路径。同时,本协议还使用考虑车辆速度和密度的动态广播机制来提高路由决策的准确性。仿真实验采用SUMO处理哈尔滨的市区地图,其中NS3的仿真结果表明VCNCM在PDR和AE2ED方面具有较大的优势。展开更多
文摘Road Side Units(RSUs)are the essential component of vehicular communication for the objective of improving safety and mobility in the road transportation.RSUs are generally deployed at the roadside and more specifically at the intersections in order to collect traffic information from the vehicles and disseminate alarms and messages in emergency situations to the neighborhood vehicles cooperating with the network.However,the development of a predominant RSUs placement algorithm for ensuring competent communication in VANETs is a challenging issue due to the hindrance of obstacles like water bodies,trees and buildings.In this paper,Ruppert’s Delaunay Triangulation Refinement Scheme(RDTRS)for optimal RSUs placement is proposed for accurately estimating the optimal number of RSUs that has the possibility of enhancing the area of coverage during data communication.This RDTRS is proposed by considering the maximum number of factors such as global coverage,intersection popularity,vehicle density and obstacles present in the map for optimal RSUs placement,which is considered as the core improvement over the existing RSUs optimal placement strategies.It is contributed for deploying requisite RSUs with essential transmission range for maximal coverage in the convex map such that each position of the map could be effectively covered by at least one RSU in the presence of obstacles.The simulation experiments of the proposed RDTRS are conducted with complex road traffic environments.The results of this proposed RDTRS confirmed its predominance in reducing the end-to-end delay by 21.32%,packet loss by 9.38%with improved packet delivery rate of 10.68%,compared to the benchmarked schemes.
文摘Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need for optimising the flow of vehicles at different intersections and reducing the waiting time is a critical challenge.Conventional traffic lights have been used to control traffic flow at different intersections and have been improved to become more efficient by using different algorithms,sensors and cameras.However,they also face some challenges,such as high-cost installation,operation,and maintenance issues.This paper develops a new system based on the Virtual Traffic Light(VTL)technology to improve traffic flow at different intersections and reduce the encountered loss of time and vehicles’travel time.Additionally,it reduces the costs of installation,maintenance and operation over various conventional traffic light systems.Consequently,the system proposes algorithms for traffic scheduling and lane identification by using vehicle ID,priority and time of arrival.To evaluate the system,four scenarios were presented where each scenario uses a different number of vehicles consisting of three types(emergency vehicles,public buses and private vehicles),each given a different priority.The proposed system is evaluated by integrating two simulators,namely,(OMNeT++)and(SUMO),and two frameworks,namely,(VEINS)and(INET)to prepare an appropriate working environment.the results prove that an improvement in the average travel time for several vehicles reaches 44.43%–49.76%compared with conventional traffic lights.Further,it is proven from the obtained results that the average waiting time for emergency vehicles is enhanced by 96.63%–97.63%,while the average waiting time for public buses is improved by 94.81%–97.23%.On the other hand,the waiting time for private vehicles‘improved by 87.14%to 89.71%’.
文摘基于路侧感知的可变车道智能网联车路协同系统是将可变车道控制系统与智能网联车路协同系统深度融合组网,其原理是在路口部署路侧感知设备来检测目标路段车流量,在其上游路口部署可变车道交通控制系统,感知设备通过识别当前道路排队长度和平均车速综合判断当前该段道路是否拥堵,然后通过车路协同系统控制上游可变车道电子标牌允许行驶方向,从而控制目标道路的驶入车流量,达到缓解该路段的交通压力的目的。同时,在车路协同C-V2X(Cellular-Vehicle to Everything 蜂窝车联网)方面,根据可变车道控制的变化规律,制作多个对应的V2X MAP导入云控平台或RSU,然后系统各单元根据相关指令设置联动下发机制,保证车路协同系统信息(MAP、SPAT)和可变车道控制系统信息(电子标牌变更指令、信号机灯组变更指令)同步对应下发,保证车路协同系统V2I红绿灯场景实现及消息的准确性和稳定性。
文摘车载自组网(vehicular ad?hoc networks,VANETs)已经成为智能交通(intelligent transportation system,ITS)的重要组成部分。在高速动态的城市环境下,为使道路车辆尽快选择到传输信息的最佳路线,提出一种基于Nakagami?m信道模型的V2X通信协议(V2X communication protocol based on Nakagami?m channel model,VCNCM),来提高数据传输率(packet delivery ratio,PDR)和降低平均端到端延迟(average?end?to?end?delay,AE2ED)。本协议采用路边基础单元(road side units,RSUs)辅助通信系统来寻找最佳的通信路径。同时,本协议还使用考虑车辆速度和密度的动态广播机制来提高路由决策的准确性。仿真实验采用SUMO处理哈尔滨的市区地图,其中NS3的仿真结果表明VCNCM在PDR和AE2ED方面具有较大的优势。
