【作者】 张卫平；

【导师】 朱树人； 肖晓丽；

【作者基本信息】 长沙理工大学 ， 计算机应用技术， 2008， 硕士

【摘要】 无线Mesh网络(Wireless Mesh Network)简称WMN,是一种新型的无线通信网络。无线Mesh网络具有自组织性和自愈的特点,并具有有效的移动用户管理和跟踪机制,是一种多跳的宽带无线网络,也是一种高容量、高速率的分布式网络。路由协议是无线Mesh网络的关键技术之一,而路由尺度是影响路由协议性能的关键参数。其中基于何种尺度进行路由选择是提高网络性能的关键。因此路由尺度问题的研究一直以来都是无线Mesh网络路由协议研究领域的热点问题。本文首先阐述了无线Mesh网络的体系结构,对无线Mesh网络中典型的路由尺度进行了研究与分析,并重点研究了近期提出的期望吞吐量尺度-ETP。针对ETP尺度所存在的缺陷,本文考虑了链路的干扰范围,同时提出了Mesh网络中节点负载的定义,并将这两者与ETP尺度相结合,提出了改进的期望吞吐量尺度-METPLB。其次对动态源路由协议DSR中的路由建立过程进行了修改,利用RREQ报文中的保留字段建立了路由尺度表,并将本文所提出的METPLB尺度应用于DSR协议中,详细描述了基于METPLB尺度的DSR协议的工作过程,并将ETP与METPLB尺度的路径选择过程进行了比较。最后,通过仿真实验研究了METPLB尺度中权值系数β的取值对网络性能的影响,并分析比较了ETP和METPLB尺度的性能。实验证明:在数据流量较大,网络负载较重的多射频多信道无线Mesh网络中,与ETP相比,METPLB尺度更倾向于选择那些运行在相同信道上的链路间干扰较小且更加独立的路径来作为路由路径,从而提高了网络吞吐量,降低了数据包端到端延迟,有效地实现了网络的负载平衡。更多还原

【Abstract】 The Wireless Mesh Network (WMN) is a new type of wireless communication network. WMN has features of self-organization and self-healing, as well as its capability of mobile user management and tracing. It is a multi-hop broad bandwidth distributing wireless network with high capacity and high transmission rate. Routing protocol is one of the key technologies in WMN, while routing metrics is an important parameter that influences the performance of routing protocol. The routing selection based on which metrics is the key issue of improving the performance of network. Therefore, the research of routing metrics is a hot spot in the area of routing protocol research all the way.Firstly, the dissertation describes the structure of wireless mesh network, then it studies and analyses the typical routing metrics, especially the expected throughput metric proposed recently. To the limitation of ETP, the interference range of link is taken into account, and a definition of node’s loading is proposed at the same time, then the METPLB metric is proposed by incorporating them into ETP metric in this paper. Secondly, the process of route foundation of DSR protocol is modified and the routing metrics table is established by making use of the reserved bit of RREQ datagram, then the METPLB metric is applied in DSR protocol, the process of DSR protocol based on METPLB metric is described in detail, METPLB and ETP metrics are compared. Finally, the impact ofβvalue to network is studied through simulating experiment, the performance of ETP and METPLB is analyzed and compared. The experiment proves that: comparing with ETP, METPLB metric is preferable to choose the path which is more disjoint and the interference of link is smaller when running on the same channel as its routing path in mutil-radio and multi-channel wireless Mesh network with heavy traffic and loading, thus to improve the throughput and reduce the end-to-end delay as well as to achieve the loading balance of network effectively.更多还原