摘要
车载自组织网络可以通过多跳无线广播实现远距离的数据传输,但网络拓扑的快速变化和无线通信质量的不稳定会导致数据传输性能的不稳定.为了应对这些挑战,文中提出了一种适用于城市场景的可靠的、连通度感知的数据分发机制.该机制利用实时收集的交通流量数据,建立路口车辆排队长度变化的马尔可夫模型,并基于此模型估算路段间无线网络连通度的实时变化,以便数据沿最小延迟路径进行转发.该机制还考虑到城市环境对无线信号的干扰,用覆盖消除规则改进了贪心广播算法,通过多候选转发策略增强了路段间数据传输的可靠性.模拟实验结果表明,与基于传染病的数据分发协议、基于静态节点的自适应数据分发协议相比,文中提出的机制能实现高可靠、低延迟的数据分发.
In VANETs（Vehicular Ad-hoc Networks）,data can be transmitted to long-distance targets through multi-hop wireless broadcast,but the rapid changes in network topology and unstable wireless communication quality will cause performance unsteady for data transmission over VANETs.To meet the challenges,a reliable and connectivity-aware data dissemination mechanism which is applicable to urban scenarios is proposed.The proposed mechanism uses the traffic-flow data collected at intersections in realtime to build a Markov model of queue length change of vehicles,and then estimate the real-time varying of connectivity of wireless networks on the roads of two adjacent intersections so as to choose the minimum delay path to forward the data.For reliable data transmission,an improved greedy broadcast algorithm which merges into coverage elimination rule and multi-candidate strategy is also designed to ease the interference of urban environments.The simulation experimental results show that our mechanism can achieve high reliable and low-delay data dissemination in comparison with the epidemic-based protocol and the static-node-assisted adaptive data dissemination protocol.
出处
《计算机学报》
EI
CSCD
北大核心
2013年第4期701-715,共15页
Chinese Journal of Computers
基金
国家自然科学基金(60970027
91124001)资助~~
