无线多跳通信网络中基于贝叶斯概率模型的消息转发机制研究

Research on Message Forwarding Mechanism Based on Bayesian Probability Model in Wireless Multihop Communication Network

摘要:

无线多跳通信网络依赖多节点中继实现信息传输，因不需要依赖预先架设的基础设施而成为军用及民用领域等特殊应用场景下的重要通信方式。为了能在复杂及恶劣环境下组网，信源节点往往采用全网广播路由请求分组RREQ的泛洪方法，以提高多跳转发路径构建成功率。然而，全网泛洪广播产生消息的冗余转发和重叠效应引起节点能耗的上升和信道利用率的下降，导致分组碰撞与网络拥塞概率的上升，严重时可能造成网络瘫痪而失去效用。本文基于贝叶斯概率论设计了无线多跳通信网络的消息转发模型，通过计算节点密度和后验概率在保证网络连通性的条件下减少不必要的消息转发。基于NS2的仿真结果表明，本文所提出的基于贝叶斯概率模型的消息转发机制能够有效减小广播分组的重播次数。相比于同类算法，在基本保证网络吞吐量的前提下，可以有效降低能量消耗、路由开销，并提高分组成功交付率，从而为未来广域大规模动态多跳网络部署提供技术支撑。

Abstract:

Wireless multihop communication network relies on multi node relay to realize information transmission without the support of infrastructure so as to become an important communication mode in military and civil fields. RREQ flooding in the whole network is always adopted for networking in complex and harsh environment. However, the redundant forwarding and overlapping effects of messages generated by the whole network flooding broadcast will cause the increase of node energy consumption and channel collision probability to decrease of channel utilization. A new message forwarding mechanism is proposed based on Bayesian probability model. The unnecessary forwarding overhead will be reduced by calculating the node density and posteriori probability. Simulation results based on NS2 show that the repeated broadcasting times can be greatly reduced by the Bayesian probability model based forwarding mechanism proposed in this paper. Compared with similar algorithms, the proposed mechanism can reduce the energy consumption, routing overhead, and improve packet success delivery rate effectively on the premise of basically ensuring network throughput, thus providing technical support for the future wide area large-scale multihop network deployment.