Research And Simulation Of Underwater Acoustic Communication And Networking Protocol

The ocean is the most dominant part of the earth,which occupies 70% of the global surface area.With the progress of human society,the development of terrestrial wireless communication technology and the advent of the 6G era,people's activities in the ocean are becoming more and more frequent,and the need for underwater communication is becoming more and more urgent.People have tried to migrate many mature and efficient terrestrial network protocols and related algorithms to hydroacoustic communication.However,many mature and efficient terrestrial network protocols and related algorithms cannot be well adapted to the underwater network environment because of the distinctive features of hydroacoustic communication such as transmission delay,narrow frequency band,low bandwidth,limited power and multipath effect,and the physical simulation in the ocean is extremely expensive and the simulation period is long.Therefore,it becomes extremely important to conduct research on communication network protocols and hydroacoustic communication simulation platforms specifically for underwater.Under this background,this thesis carries out research on the structure of hydroacoustic communication networks and the characteristics of hydroacoustic channels,proposes a MAC negotiation strategy(DMMAC)based on energy cross-layer optimization,designs and implements a hydroacoustic communication simulation platform,simulates a real marine environment,demonstrates the process of underwater information transmission,and overcomes the characteristics of long physical simulation cycle,high overhead and restricted conditions.1.This thesis studies the structure of hydroacoustic communication network and the characteristics of hydroacoustic channel,analyzes the overall protocol stack structure of hydroacoustic communication network,and focuses on the protocol of MAC layer.Through the study of Slotted FAMA design process and main workflow,it is clear that the main purpose of protocol design in this thesis is to reduce the collision rate of underwater transmission data and improve the lifetime of communication network.This thesis also studies the recent hydroacoustic communication simulation platforms,and analyzes and summarizes their advantages and shortcomings.Meanwhile,the network framework and module operation mechanism of NS-3 and Aqua-SIM-NG network simulation simulators are studied to provide the theoretical basis for the design and implementation of the hydroacoustic communication simulation platform in this thesis.2.This thesis proposes an energy-based cross-layer optimization MAC negotiation strategy(DMMAC).The protocol calculates the optimal transmission packet size by the distance between nodes,thus reducing the transmission collision probability;meanwhile,the residual energy of nodes is considered when selecting the transmission path,and the utilization of nodes is improved by optimizing the transmission path in order to improve the lifetime of communication networks.The model and algorithm are implemented in C++,and the superiority of DMMAC protocol is verified by simulating and comparing with RTS/CTS and Slotted FAMA protocols.3.In this thesis,a hydroacoustic communication simulation platform based on NS-3 and Aqua-SIM-NG simulators is designed and implemented.In addition to retain NS-3 and Aqua-SIM-NG basis functions,the simulation environment is reasonably configured and the overall framework and software architecture of the simulation platform is designed.Simulation experiments are conducted through test cases,and the results show that the hydroacoustic communication simulation platform supports more than 2 typical channel transmission models and 3D topologies,supports link layer and network layer protocol performance statistics and evaluation,reduces experimental costs,improves experimental accuracy,flexibility and experimental efficiency.