Research On UAV Path Planning And Strategy Base On Age Of Information

With the continuous maturity of UAV technology,its advantages of high mobility and low maintenance cost have promoted the vigorous development of UAV relay technology.In scenarios where the signal coverage of the base station is incomplete,such as mountains or forests,the UAV can be used as a fast air relay platform to collect the sensing data of the ground sensors and forward it to the base station for subsequent processing.Due to the limited endurance of unmanned aerial vehicles,the current research on unmanned aerial vehicles mainly focuses on the flight path planning with the best energy efficiency.With the emergence of real-time detection applications,the base station has become increasingly demanding on the timeliness of data collected by sensors.Therefore,based on the concept of information age,this paper studies UAV trajectory planning and relay strategies aiming at optimizing the timeliness of information.On the one hand,due to the limited energy of the ground sensor node,its transmission range is limited.How to design the optimal time-effective UAV relay strategy and flight trajectory according to the remaining energy of the node while ensuring the information collection integrity of each node is a question worth studying.On the other hand,due to the mutually restrictive relationship between UAV flight energy consumption and relay information timeliness,how to accurately characterize the trade-off relationship between UAV relay energy consumption and information timeliness,based on actual system parameters choosing the best cost-effective trajectory is a question worth studying.In order to solve the above two key issues,the main contributions of this article are as follows:(1)Aiming at the problem of information relay in the case of multiple ground nodes,this paper takes the timeliness of the relayed information as the optimization goal.Consider the energy constraints of the ground nodes and the constraints of the minimum amount of information transmitted by the nodes,and jointly optimizes the UAV flight trajectory and Information relay strategy.First,this paper considers three modes of relay strategy,namely hover strategy,flight strategy and hybrid strategy.In this paper,based on the energy of the ground nodes and the limitation of the amount of information transmitted,a two-dimensional search algorithm is used to select the UAV information relay mode with the best timeliness,and the flight speed and hover time during the UAV relay process are solved.Furthermore,when the relay strategy at each node is known,based on the dynamic programming algorithm,the flight path of the drone in multiple nodes with the best timeliness is solved.Simulation results show that the trajectory based on information timeliness can greatly improve the timeliness of information compared to the trajectory based on minimum flight energy.The simulation results also show that under the condition of node energy constraints,the timeliness of relay information can be further improved by optimizing the UAV information relay strategy.(2)Considering the mutual constraint between the UAV flight energy consumption and the timeliness of relay information,for the information relay problem in a single-node scenario,this paper derives the UAV flight energy consumption and relay under straight and circular trajectories.Find the Pareto relationship between the timeliness of the information,and then the Pareto boundary value under the given node spacing,and obtain the optimal flight trajectory and flight speed for energy efficiency and timeliness.According to the obtained Pareto curve,the timeliness of the optimal information can be obtained based on the flight power range,and the minimum flight energy required can be obtained based on the timeliness requirements.The simulation results also show that,based on the deduced Pareto relationship between the UAV flight energy consumption and the timeliness of relay information,it is possible to optimize the timeliness of relay information by optimizing the flight path and flight speed of the UAV.At the same time,the energy consumption of the UAV is minimized,thereby further improving the performance of the UAV relay system.