Joint Optimization of Spectrum Resource Management and Position Placement for UAV Base Station Networks

Algorithm 2

BR-based position placement algorithm.

Initialization:

 (1) Initialize the UAV position as

 (2) Set iteration times and max iteration times

While:

 (3) Update

 (4) Execute Algorithm 1 within position strategy , then receive the corresponding the UAV-user association and channel selection strategy , where

 (5) Randomly select a UAV . Calculate UAV ’s payoff according to formula (19)

 (6) UAV explores 8 positions near the position

  (a) The current position explored is denoted as where , , and

  (b) Execute Algorithm 1 within position strategy , then receive the corresponding the UAV-user association and channel selection strategy

  (c) Calculate UAV ’s payoff according to formula (19)

  (d) If , update and jump to step (9), else keep exploring other locations

 (7) Randomly select a position throughout the mission area, do the same process as step (4) and (5), then calculate the payoff

 (8) If , update

 (9) Update

End loop.

is the exploration step size of the UAV and becomes shorter as the iteration increases.