Research On Trajectory Optimization Technology For UAV Collaborative Deployment

In recent years,with the development of Unmanned Aerial Vehicle(UAV)in terms of endurance time and intelligent control,and the characteristics of UAV with mobility,flexibility,high controllability,and establishment of good line-of-sight links,the network service provided by UAV base stations for ground users has become a research hotspot at home and abroad.For example,UAVs are used as aerial base stations to expand the coverage of existing wireless networks,increase capacity,and communication reliability.It can also be used as mobile terminals in cellular networks to perform tasks such as item transportation,data collection,and video surveillance.In these application scenarios,the realization of UAV location deployment and trajectory optimization is one of the key technical issues that need to be urgently solved in the field of wireless communications.Therefore,in this context,this paper studies the location deployment and trajectory optimization of UAV base stations in the field of wireless communication.In the UAV base station communication problem,the air-to-ground channel model research is the basis of other problems,so this paper first summarizes the air-to-ground channel model.This paper studies the radio model in low-altitude flight platform and the method of establishing the radio model,and summarizes and simulates the model used in this study,which can be used as the theoretical support for the channel model in the deployment and trajectory optimization of UAV base station.Secondly,in order to ensure user service quality and solve the problem of static multi-UAV base stations covering the same number of users with minimum transmit power,an optimized deployment method for UAV base stations based on minimum encircling circle and improved K-means algorithm is proposed.Based on the greedy algorithm,the deployment problem is decoupled into the vertical and horizontal minimum encircling circle problems,and the three-dimensional deployment position of the UAV base station is determined by solving the optimality separately.Use clustering methods to build user clusters and optimize the deployment location of UAV base stations.With the goal of minimizing communication energy consumption,the UAV base station communication model and its solution method are used to determine the optimal flying height of the UAV.Simulation results show that the optimization method proposed in this paper can significantly reduce the transmitting power of UAV base stations.The problem of UAV base station trajectory optimization in the ground equipment moving scenario is further studied,and proposes an energy-saving communication trajectory optimization method for UAV base station based on the optimal transmission theory.Taking the reduction of the total transmission power of the device as a constraint,the K-means algorithm is used to perform cluster analysis on the ground equipment.Update the optimal service location of the UAV base station according to the clustering result of the device,to achieve the minimum transmission power of the device after each update.Finally,the optimal transmission theory method is used to optimize the trajectory between discrete UAV base station positions to achieve the purpose of energy-saving mobile UAV.Simulation results show that the dynamic deployment method can effectively reduce the transmit power of the device by 70%.