Dynamic Clustering And Opportunity Routing Research In UAV Ad-hoc Network

In the modern information warfare,UAVs have played an important role of information delivery.Flexible,efficient and strong anti-destroying UAV ad hoc network made up of UAV formation not only can guarantee UAV formation to collaborate to complete combat missions,but also can adopt the way of wireless "hot zone" to cover the combat area in order to achieve efficient coordination of information,tactics and firepower between combat units.In this paper,considering the characteristics of UAV formation's flight and dynamic changes of network topology,the advantages of network clustering and inter-cluster opportunity routing in UAV ad hoc network are deeply analyzed.We explore the network clustering algorithm based on the UAV path planning and the method of inter-cluster opportunistic routing protocol based on the available bandwidth of the link.The research results provide technical support and reserve for the development of UAV network data link system.The main innovations are as follows:(1)Weighted efficient clustering methods based on path planning of UAV ad hoc network are proposed.In combat,UAV ground control station uses the path planning algorithm to preset UAV formation's flight path that the optimal path from the initial position to the target position in dangerous region is presented.In terms of this,we first adopt particle swarm optimization algorithm to realize UAV path planning in the region with danger zones.Then two weighted efficient clustering method based on path planning of UAV ad hoc network(WHEA-P and WCAA-P)are proposed.Both algorithms take account of the stability of cluster based on path planning,the distribution of nodes and the remaining energy of nodes as the clustering weighting factors.WHEA-P algorithm aims at the stability of cluster-head,while WCAA-P algorithm focus on the stability of cluster member.Fully considering the influence of UAV formation's topology changes,the simulation results show that compared with the traditional the least ID cluster algorithm and WCA,both two algorithms have less clustering maintenance overhead,more the stability of clustering,and the better network lifetime performance.(2)Available bandwidth estimation based opportunistic routing protocol are proposed.Inter-cluster routing protocol is the key to guarantee the performance of clustered UAV ad hoc network.If we adopt the traditional routing protocol,the cluster-head re-election,the dynamic changes of the network topology and the long-distance wireless link's rupture will lead to a new route discovery process and consume a lot of wireless links transmission resources during the flight of UAVformation.In contrast,the opportunistic routing protocol does not need the node to maintain the routing table,and adopts the method of inter-node's competition to determine the forwarding node in next hop until the data packet reaches the destination node.This paper assumes that the UAV node's data link layer adopts carrier sense multiple access/collision detection(CSMA / CA).Firstly,making use of the available bandwidth prediction method of UAV in high dynamic environment,an opportunistic routing protocol based on the available bandwidth of link is proposed.Based on the available bandwidth and forwarding distance of the node's current link,the protocol calculates the priorities of the relay nodes and determines the next-hop routing.The simulation results prove the superiority of the protocol.