Abstract: Unmanned Aerial Vehicles (UAVs) plays an important role in wireless networks due to the advantages of high mobility and high line-of-sight communication probability.Therefore,joint optimization of UAV 3-D position and transmit powers for throughput maximization (JPTM) algorithm is proposed in this paper.In JPTM,joint optimization problem of 3-D placement and transmit power of UAV was established to maximize the throughput.The problem was a nonconvex optimization problem,and the problem is divided into two optimization problem.The first optimization problem is solved by Mean-shift algorithm and the optimal horizontal locations of UAVs are calculated.The second optimization problem are decomposed by divide-and-conquer strategy,and the sub-problem are approximated by first-order Taylor expansion.The sub-problem is formed to be standard convexity problem,which is solved by CVX tool.Simulation results have demonstrated that JPTM results in throughput performance as compared to Circle Packing Theorem-based Deployment (CPTD) of UAVs and Energy-Efficient Variable simultaneous Deployment (EEVD) algorithm.

Key words: UAV communication, 3-D deployment, Transmit power optimization, Mean-shift algorithm, First-order taylor expansion