摘要
在Ad Hoc网络的仿真研究中,节点移动模型的选择会严重影响到网络的拓扑结构和通信协议的性能.然而,现有移动模型大多是为理想环境设计的,不能适用于真实环境.在理想移动模型RWP(Random Waypoint)的基础上,提出了具有多出入口区域的RWP节点移动模型(RWP with entrances,RWPWE).在该模型中,区域出入口是节点进出区域的必经之地,节点在区域内的移动符合RWP节点移动模型,通过引入域内停留概率来完成节点在区域内外移动的转移,并从节点移动速度、移动时间、移动路程和空间分布概率等几个方面研究了区域出入口的影响.理论分析和实验仿真的结果表明,由于出入口的存在,与RWP模型相比节点的移动更加复杂,节点的空间分布也显著不同,这些差别将会影响到网络的拓扑性能和对网络协议的评价.
In simulation of ad hoc networks, the choice of underlying mobility models has a great influence on the network topology and performance of protocols. However, most of the existing mobility models that are designed for idealistic cases can not provide realistic movement scenarios. On the basis of RWP （Random Waypoint） mobility model, a novel realistic mobility model, RWP with entrances in the terrain （RWPWE）, is proposed. In the proposed model, 1） There is at least one entrance on the edge of or in the terrain; 2） The movement pattern in a terrain can be described by RWP model; and 3） The node transfer from inside the terrain to outside through entrances is decided by the probability staying inside the terrain. The influence of entrances on the node mobility is characterized by the attributes of nodal velocity, transition time, transition length and spatial distribution in the terrain. Theoretical analysis and simulation show that due to the existence of terrain entrances the node mobility is more complex and nodal spatial distribution is greatly different from that of RWP model. Moreover, these differences have a significant impact on ad hoc network topology and the performance of protocols eventually.
出处
《计算机研究与发展》
EI
CSCD
北大核心
2008年第3期428-435,共8页
Journal of Computer Research and Development
基金
综合业务网理论与关键技术国家重点实验室基金项目(00JS63.2.1.DZ01)
