水声网络MAC协议综述

Summary of MAC Protocol of Underwater Acoustic Network

无线电信号与光信号在水下通信过程中衰减严重,因此,水下主要通过声信号来进行通信。水声网络具有高能耗、高拓扑移动性、低可用带宽等固有特性,这些特点给水下MAC协议的设计带来了一定的挑战。本文对水声网络MAC协议进行综述,介绍水声信道特点与衰减。除此之外,阐述水声网络中存在的隐藏终端、暴露终端等五种问题给MAC协议的设计所带来的困难;分析水声网络MAC协议的分类及相应的优缺点;比较近年来典型水声网络MAC协议的性能。目前有许多优秀MAC协议解决了隐藏终端等问题,但实际水下环境中存在的拓扑移动性和时间同步问题仍是水声网络MAC协议设计的难点,未来着力研究并解决实际水下环境中存在的拓扑移动性和时间同步问题。

Radio signals and optical signals are seriously attenuated during underwater communication.Therefore,underwater communication is mainly carried out through acoustic signals.Underwater acoustic networks have inherent characteristics such as high energy consumption,high topology mobility,and low available bandwidth,etc.These characteristics have brought certain challenges to the design of underwater MAC protocols.This article reviews the MAC protocol of the underwater acoustic network,and introduces the characteristics and attenuation of the underwater acoustic channel.In addition,it explains the difficulties in the design of MAC protocol caused by the five problems of hidden terminals and exposed terminals in the underwater acoustic network;analyzes the classification of the underwater acoustic network MAC protocol and the corresponding advantages and disadvantages;compares the performance of the underwater acoustic network MAC protocol of typical recent years.At present,there are many excellent MAC protocols that solve the problems of hidden terminals,but the topological mobility and time synchronization problems in the actual underwater environment are still difficult points in the design of the MAC protocol of the underwater acoustic network.In the future,we will strive to study and solve the topological mobility and time synchronization problems existing in the actual underwater environment.