Research On Routing Protocols For UAV Ad Hoc Networks

In recent years,with the rapid development of various high-tech and various new auxiliary equipment,the performance of UAVs has been continuously improved,and they are playing an increasingly important role in both military and civilian fields.Clustered UAVs have ability to fly collaboratively and can form multi-hop,centerless,autonomous UAV ad hoc networks.In this networking mode,each UAV node does not depend on the infrastructure and completes the interaction of information through multi-hop routing,which can theoretically break the limitation of distance and greatly enhance the information collection capability.However,the characteristics of UAVs,such as high-speed mobility,limited energy and limited bandwidth,can lead to frequent changes in the topology of UAV ad hoc networks,and the established routes are highly susceptible to be crack,which seriously affects the performance of UAV ad hoc networks.Therefore,this thesis presents an in-depth study of UAV ad hoc networks from the perspective of designing stable and efficient routing protocol.The main work can be summarized as follows:Firstly,to slove the characteristics of frequent topology changes of UAV ad hoc networks,the thesis proposes an AODV routing protocol based on mobility prediction.This protocol is based on the AODV protocol with the following three main improvements:(1)predicting the motion trajectory of UAVs based on Gate Recurrent Unit(GRU)network and dividing the stability domain and setting the concept of stability for the nodes;(2)improving the routing algorithm to take the stability of links as the basis for route selection;(3)improving the HELLO message packet mechanism to be better used in the route discovery and route maintenance phases.The simulation results show that the protocol has better network performance compared with AODV.Secondly,considering the business requirements of UAV ad hoc networks,based on the above research,the thesis proposes an AODV routing protocol based on link quality.This routing protocol takes the stability of the link,the available bandwidth of the nodes,the residual energy and the queue length into account,and defines the routing quality of the whole route,which is used as the basis for the route discovery and route maintenance.Simulation results show that the protocol not only takes the Quality of Service(Qo S)requirements into account,but also can establish reliable routing.The protocol performs well in both high mobility and high load scenarios.