Research On Capacity Of Scale-Free Wireless Network Based On Unmanned Aerial Vehicle

Unmanned Aerial Vehicle(UAV)technology has been considerably developed in the past decade and has received extensive attention from the market.Drone technology and 5th generation mobile communication technology(5G)are further combined,so that drone wireless networks have become one of the important applications in the industry.A network regularly consists of hundreds or thousands of drones.This results in a particularly large network scale,showing a certain scale-free characteristic.This paper mainly analyzes the scale-free wireless network capacity based on drones,and specifically focus the following:1)First of all,the modeling and the theoretical throughput capacity of 3D scale-free wireless network,of which nodes transmit in a point-to-point format,is studied.Due to the mobility of drones,the network is generally distributed in a three-dimensional space.This paper utilizes the wireless network scaling-law to divide the unit cube space into cubic grids for setting up the routing scheme and the transmission mechanism.Meanwhile,multiple parameters are used to describe the power-law characteristic of wireless scale-free networks:? is the parameter for the source node to construct the transmission community,as well as ? is the communication probability parameter for the internal node.The selection of these two target nodes follows the inverse proportionality of the power-law with the distance from the source node.? represents the parameter of the actual topology connectivity,reflecting the degree of sparsity of the network.Then,this article divides the nodes into two categories according to the connectivity degree of the node community:the nodes with a high connectivity degree are scale-free nodes,and other nodes are ordinary nodes.Moreover,the average hops of these two types of nodes and asymptotical boundaries of network capacity are obtained respectively.2)Next,a three-dimensional scale-free wireless network generation algorithm,which is based on the BA scale-free algorithm,is proposed.New nodes are connected to the network preferentially according to the community's connectivity.The topology of the network is constantly changing over time,for the network is random.This algorithm innovatively generates a transient communication topology to achieve the purpose of Monte Carlo experiments on time-average hops and throughput.Corresponding simulations verify the correctness of the theoretical analysis.3)Finally,a hybrid network with cellular infrastructure is considered.The capacity of pure ad hoc networks is limited by the number of nodes.Therefore,cellular base stations are introduced to further increase the capacity of the UAV network.Nodes can choose two transmission fashions,using threshold L of multi-hop count as the division.If the hop count is smaller than L,the flow consumes ad hoc resources,or else cellular resources are used.The analysis proves that the size of L affects whether the transmission flow is dominated by scale-free nodes or ordinary nodes.Besides,for different power-law parameters,there are different optimal L ranges,forming the highest network capacity bound.In the end,the main work of this paper is summarized,and future research directions are prospected.