【摘要】 首先介绍了面向智能交通系统(Intelligent Transportation System,ITS)的无线接入网网络结构和主要业务,对车路协同业务和PTT语音业务进行了分析和建模。然后根据不同业务的特点及QoS需求提出具有针对性的调度方案:对于车路协同业务,采用适应车速的动态调度方法;对于PTT语音业务,采用基于状态转换的调度方法;对于视频和其他对时延不敏感的数据业务,采用缓存请求的调度方式。最后在OPNET平台上对调度方法进行仿真,针对各种ITS业务得出延时、丢包率等性能曲线,验证了算法的有效性,这也为ITS接入网的网络设计提供了参考。更多还原

【Abstract】 This paper first described the architecture and the main services of the wireless network oriented ITS(Intelligent Transportation System).The services of Cooperative Vehicle-Infrastructure System and PTT voice were analyzed and modelled.Pointed scheduling schemes were proposed for different services according to their QoS requirements.For the service of Cooperative Vehicle-Infrastructure System,vehicle speed adapted dynamic scheduling is adopted.For the service of PTT voice,scheduling based on state transition is adopted.For the video and other services which are not sensitive to delay,scheduling request is generated based on buffer status.Finally,the scheduling schemes were simulated on OPNET,from which the availability was verified with performance curve of delay and packet loss rate.This also provides reference for ITS access network design.更多还原