中文摘要：

MAC协议决定了水声信道的使用方式,作为水声网络的关键技术之一,它越来越受到人们的普遍关注,它的研究对水声传感器网络的发展具有至关重要的作用.经过分析比较现有的陆上无线通信协议,选取其中性能较适用于水声信道的TDMA、802.11和S-MAC协议进行研究分析,对三者的各方面性能进行比较,并针对水声信道特点提出改进方案：利用TDMA的时延,交错设置帧周期;使IEEE802.11协议一次握手传输多个数据并采用周期性睡眠机制;对SMAC协议采用事先预测网络流量,动态调整占空比.设计了水声信道MAC层协议的仿真方法,通过修改NS2中已有无线通信协议的物理层和链路管理相关代码,实现了水下通信环境的模拟。

英文摘要：

MAC protocol determines the way of using multipath underwater acoustic channel. As one of the key technology of underwater acoustic networks,it gets more and more attention of people. The MAC protocol research plays the vital role in the development of underwater acoustic sensor networks. Through the analysis and comparison of the existing land wireless communication protocol,this paper chooses and analyzes the performance of TDMA,802. 11 and S-MAC protocol which is suitable for underwater acoustic channel. By comparing the performance of the three protocols and combined with the characteristics of underwater acoustic channel,improvements are suggested： Using TDMA time delay,the frame period can be setted; Transmitting more data in a handshake and using the periodic sleep mechanism in IEEE802. 11protocol; Predicting network traffic in advance,and adjusting the duty ratio dynamically in the SMAC protocol. Thesis designs the simulation method of MAC layer protocol in underwater acoustic channel. By modifying the existing wireless communication protocol and link management related code in NS2,this paper realizes the simulation of physical in underwater communication environment.