无线自组网多径路由算法研究

【作者】 张媛媛；

【导师】 郭伟；

【作者基本信息】 电子科技大学 ， 通信与信息系统， 2009， 硕士

【摘要】 无线自组网(Ad hoc Network)由一组带有无线通信收发装置的移动终端节点组成,是一个多跳的、临时性无中心网络,不需要基础网络设施的支持,网中每个节点可以自由移动。在这种环境下,由于终端的无线覆盖范围的有限,一个移动主机可以借助于其他节点将分组转发至目的节点,所以每个节点可以说既是终端也是路由器。Ad Hoc网络的应用范围也从军事应用逐渐转向民事应用,其应用范围越来越广泛,例如:突发事件的恢复、人群控制、寻找和救援等。Ad Hoc网络具有很多其他网络所不具备的优势。但是,由于Ad Hoc网络的节点能够任意移动,路由随时都有中断的可能,从而导致了路由具有不可靠、不稳定的特性。因此,路由技术成为了研究Ad Hoc网络的关键。多径路由(Multi—path)是在路由建立过程中同时建立和维护多条预留路径。多径路由无论在路由延迟、容错性、可靠性等相比于单径路由都有更好的性能,特别是在动态拓扑变化频繁的网络中。另外多径路由也应用于网络负载平衡。因此,在Ad Hoc网络中,多径路由备受关注。本文第一章介绍了Ad Hoc网络,包括了Ad Hoc网络的定义、特点、应用领域及关键技术等。第二章对当前Ad Hoc网络的路由技术研究现状作了分析,并对相应的路由协议进行了比较。第三章对当前Ad Hoc网络多径路由技术研究现状作了分析,并对相应的路由协议进行了比较。第四章结合多径路由的思想,提出了一种新的AODV路由改进算法CLLB—AODV。该算法采用MAC层非空闲带宽估计节点负载,并根据路径负载来决定路由的选择。第五章是在AODV路由算法的基础上提出了一种节点不相交多径距离向量算法AODV—NDMR,实现了源节点到目的节点的多条节点不相交路由的建立、维护和传输控制机制。第六章首先介绍了仿真系统,并在OPNET平台上分别对CLLB—AODV和AODV、AODV—NDMR和AODV进行了仿真。通过仿真比较了AODV路由算法和CLLB—AODV路由算法、AODV路由算法和AODV—NDMR路由算法的性能。仿真结果表明,本文所提出两种路由算法CLLB—AODV和AODV—NDMR比AODV路由算法有性能改进。更多还原

【Abstract】 Ad hoc network consists of a set of mobile nodes with wireless communication transceivers.It’s a multi-hop temporary network without centralized control or fixed network infrastructure.And each node in the network can move freely.In such an environment,it may be necessary for one mobile host to seek the aid of others in forwarding a packet to its destination,due to the limited propagation range of each mobile host’s wireless transmissions.Thus each node acts as router as well as a terminal. With development of ad hoc network changing from military to civilian use,more and more applications are jointed into mobile ad hoc network,such as:disaster recovery, crowd control,search and rescue,etc.In many ways,Ad Hoc network is better than many other networks.But,nodes Varese able to move,routing may be lost at any time.Router losing makes the routing unreliable and instable.To overcome of these difficulties becomes the key of ad hoc network study.Multi—path route protocol computes and maintains alternative Multi—paths in routing finding process.Multi—path has better performance than single path routing protocol whenever in delay,error tolerance reliability.Any more,Multi—path routing protocol is used in load balance of ad hoc network too.So Multi—path routing protocol is focused in ad hoc network.Ad hoc network is introduced in chapter one,including the definition, characteristic,application fields and key technologies of ad hoc network.The analysis of research actuality of network route technology is conducted in chapter two.In chapter three,we introduce the backgrounds of the Multi—path routing protocol.Then some existing routing protocols are compared and researched in features and performance.A new improved AODV Multi—path routing algorithm,named CLLB—AODV, is addressed in chapter four.The traffic of MAC layer to estimate node’s load and choose paths according to path’s load.In chapter five,we introduce an AODV-based node-disjoint distance-vector multi-path routing protocol——AODV—NDMR, that establishes and maintains multiple node-disjoint paths for data transmissions.In chapter six,we introduce simulation system.We use OPNET to simulate the protocols of CLLB—AODV、AODV—NDMR and AODV.The simulation results have confirmed that CLLB—AODV and AODV—NDMR routing protocol have a better performance in data packet delivery ratio,end-to-end delay and throughput compared with the routing AODV protocol.更多还原