School of Communications Engineering;
Army Engineering University of PLA;
Nanjing 210007;
China;
School of Electronic and Information Engineering;
Nanjing University of Aeronautics and Astronautics;
Nanjing 210016;
China;
Outage probability; Primal-dual subgradient; Proactive optimization; Successive convex approximation; Unmanned Aerial Vehicle(UAV)relay;