节点文献
一种浅海水声通信网络通信协议的设计
The Design of Communication Protocols of the Shallow Water Acoustic Networks
【作者】 魏俊博；
【导师】 周东辉；
【作者基本信息】 中国海洋大学 ， 通信与信息系统， 2007， 硕士
【摘要】 本文主要对水声通信网络通信协议进行了研究与设计。通过设计模拟一个小规模水声通信网络,研究水下信道传输带宽窄、多径衰落严重和延时大等特性对通信的影响,探讨水声通信网络通信协议的描述和实现方法。主要工作如下:首先,探讨了水声通信网络的研究意义,概述了国内外水声通信网络(包括水声传感器网络拓扑及协议部分)的研究成果,提出了本文的研究内容和研究方法。其次,分析了海洋水声信道的特性,包括海水中的声传播速度、水声信道的有限带宽性、空变、时变、随机性、多径传播以及衰落特性等,研究了上述特性对水声通信的影响。再次,探讨了水声通信网络的组成结构以及通信协议各层的任务、功能以及主要技术。在以上研究工作的基础上,选择了一个以多径传输为主要模拟对象的简化的浅海水声信道模型。通过定量分析,选择了多跳式的网络拓扑。通过比较水声通信网络各种协议的实现算法,设计了适合于浅海水声信道的通信协议集。其中物理层的调制方式为2FSK;数据链路层的信道共享协议为基于停等ARQ的改进式MACA协议,同时使用基于频分双工的DS-CDMA对信道进行复用;网络层使用固定的路由树,在初始化之后,网络重建之前,路由不变。然后,在仿真软件中搭建了一个由6个节点组成的浅海水声通信网络模型后,选取了合适的统计量对设计的网络进行了仿真。仿真结果表明,该网络在浅海环境下,端到端时延较长,围绕65s上下波动,同时头节点的功率消耗随着时间而呈现增加变缓的趋势。最后,对所作的工作进行了总结,对以后的研究做出了展望。
【Abstract】 This paper mainly studies the communication protocols of underwater acoustic networks. Via simulation, a shallow-water acoustic network is designed. After researching the characteristics of underwater channel, the characterization and realization of communication protocols which are befitting underwater are discussed. The main aspects of this paper are:At first, the significance and the research focus of underwater acoustic networks are discussed. Based on the summarizing the present research states which is in-country and overseas, the main idea of the paper is put forward.Secondly, this paper analyzes the characteristics of underwater acoustic channel, and studies the influence.Thirdly, the architecture of underwater acoustic networks and function and main technologies of the different layers of communication protocol are discussed.Fourthly, based on the study above, a simple shallow-water acoustic channel model is chosen to mainly simulate the multi-path underwater. Afterwards, the different protocols of different layers are compared to design a suitable protocol stack for underwater channel. The modulation schemes of physical layer is 2FSK; the Media Access Protocol is improved MACA based on stop-and-wait ARQ, at the same time, DS-CDMA is used; fixed routing tree is used, it will fixedness between initialization and rebuilding.Afterwards, an Opnet model is built to analyze the performance of the network designed via choosing befitting measurement. As result, the end-to-end delay is long, and the average is about 65s; the increment of battery consumption of master node is decreased as a function of timeAt last, the paper summarizes the content of this paper.