一种面向车辆自组织网络的分布式成簇算法

Distributed Clustering Algorithm for Vehicular Ad Hoc Network

在车辆自组织网络(VANET,Vehicular Ad Hoc Network)中,由于车辆之间速度大小、移动方向的差异,车辆间的通信链路十分脆弱.采用基于层次结构的成簇机制是提高车辆自组织网络的通信质量的重要方法之一.然而目前大多数成簇算法的设计是基于高速路场景,并不适用于车辆行驶速度、行驶方向变化频繁的城市环境.针对上述问题,提出一种基于通信链路稳定性的分布式成簇算法,考虑车辆节点在城市环境中更易改变运动方向的移动特性,根据节点及其邻居节点的当前移动方向,估算节点选择不同运动方向的概率,同时结合节点相对位置和速度大小,预测车辆间的通信时长,评估车辆间的稳定性以形成稳定的簇团.仿真结果表明,本文提出的成簇算法在簇团结构稳定性、簇团划分效果等方面均优于其他比较算法.

In vehicular ad hoc network （VANET）, due to the differences of speed and moving direction between vehicles, the communication links are extremely weak. To improve communication quality in VANET, the hierarchical structure of clustering nodes into groups is proposed as one of important techniques, while most existing clustering methods are designed for highway environment, which are not suitable for urban scenario where vehicles frequently change their moving speeds and directions. This work proposes a distributed, communication link-stability based clustering algorithm for VANET, which considers the mobility feature of VANET in the urban environment that vehicle nodes are much easier to change its moving direction. According to the current moving directions of the node and its neighbors, this proposed algorithm estimates the node selection probability of moving in different directions and then forms stable clusters by combining with the node relative position and speed to predicate the communication link time between vehicles and evaluate link stability of vehicles. The results of the simulation indicate that this proposed clustering scheme achieves better network performance in terms of cluster stability, cluster partition result when compared to other clustering algorithms.