摘要
车联网信道资源稀缺及车载节点间的间歇性短暂链接,给车载节点通过无线接入点(AP)接入互联网进行内容下载带来了巨大挑战.AP覆盖范围内的资源分配与Internet链接空洞区域的传输调度相互依赖,共同影响其下载性能,而现有文献往往将二者孤立开来分别进行研究.为了提高下载性能,将二者作为一个整体,从全局优化的角度研究内容下载的效率问题,并将其形式化为下载数据量最大的结合非冲突调度的资源分配问题.但是,在证明该问题是NP-难的基础上,提出结合链接空洞区域的传输调度的资源分配近似算法(JAS)来解决该问题.该算法将整个链接空洞区域节点间链接的时空变化模型化为拓扑图序列,并基于此构建其传输冲突图序列,在AP通信覆盖区域基于图序列计算优化的资源分配节点集进行资源分配,以期达到扩展AP通信范围、填补Internet链接空洞的目的.模拟实验结果表明,JAS算法与现有方法相比显著提高了文件下载量及传输的成功率.此外,还对影响内容下载性能的相关因素进行了分析.
Vehicular content downloading via open WiFi access points （APs） can be challenging due to sparse AP deployment with bounded communication range and the rapid movement of traveling vehicles. For drive-thru networks, resource allocation and scheduling closely interrelate to and interact with each other, collectively affecting the performance of content downloading. However, none of the previous work has tackled this problem as a whole. This paper discusses joint resource allocation and scheduling problem for efficiently content downloading considering channel contention and scarce AP resource utilized effectively. It formalizes optimization selection problem of node set to maximize the total quantity of data downloaded, and proves that it is NP-hard. Further, it presents a solution with a joint resource allocation and scheduling approximate algorithm （JAS）. Theoretical analysis and simulation results both verify that the presented implementation achieves higher throughput and delivery ratio than the existing algorithms.
出处
《软件学报》
EI
CSCD
北大核心
2014年第10期2362-2372,共11页
Journal of Software
基金
国家自然科学基金(60803148
60973124
61300210
61370214)
教育部高校博士点科研基金(20102302110036)
关键词
车联网
车载adhoc网络
无线网络接入点
车间通信
内容下载
drive-thru Intemet
vehicular ad hoc network （VANET）
access points （APs）
vehicle-to-vehicle （V2V）
content downloading
