Research On UAV Data Transmission Technology Based On Energy Optimization

UAV has the advantages of mobility and flexible trajectory control,which can greatly improve the communication efficiency and have a larger coverage.Non-orthogonal multiple access is a popular technology in future wireless communication.It can stack user signals in power domain to serve multiple users on the same time-frequency resource.The combination of UAV Communication and noma technology,making full use of the advantages of both,can improve the efficiency of communication system.However,due to its small size and limited energy,the endurance of UAV is greatly affected by its energy consumption.The energy consumption of UAV is the bottleneck of the development of UAV-NOMA system,so it is of great significance to study how to effectively use the limited airborne energy in UAV Communication.Aiming at the energy limitation of UAV-NOMA communication system,the paper focuses on the energy consumption schemes of UAV data transmission technology based on NOMA technology in different scenarios,including the following two aspects:Aiming at the static UAV-NOMA communication scenario,based on the minimum transmit power problem of the user error rate limit,the article proposes a NPM(NOMA Power Minimization)algorithm to solve the optimal transmit power of the UAV.Based on imperfect SIC conditions,the article studies the optimal UAV transmission power that meets the bit error rate requirements of two users,and analyzes the optimal power allocation factor for the two users.Next,the article proposes the NPM algorithm to analyze the optimal solution of the model.The simulation results show that the UAV transmission power obtained by the NPM algorithm is much smaller than the transmission power obtained in the fixed two-user power allocation factor scheme.Compared with the weak users of NOMA,the bit error rate requirements of strong users have a greater impact on the minimum transmission power of UAVs.Considering the dynamic UAV-NOMA communication scenario,aiming at the problem of maximizing the minimum user energy efficiency,the paper studies the optimal flight trajectory and user scheduling scheme of UAV to meet the requirements of UAV position,speed and acceleration.Based on the block coordinate descent method and continuous convex approximation technique,an efficient iterative algorithm is proposed to obtain the optimal trajectory and user scheduling function of UAV.The simulation results show that the flight trajectory of UAV is consistent with the theoretical analysis.Compared with the UAV trajectory obtained by maximizing the minimum user throughput,the ground users can achieve better energy efficiency in the same flight time.