Joint Optimization of Placement and Coverage of Access Points for IEEE 802.11 Networks

Although many efforts have been devoted to the access point (AP) placement problem in IEEE 802.11 networks, most of them assumed that the positions of users are fixed and formulated it as a deterministic optimization problem. In this paper, with the time-varying nature of users' positions taken into account, we establish a stochastic optimization framework to jointly optimize the positions and coverage radius of APs. The aim is to maximize the average network throughput under an outage probability constraint. With both the objective and constraint functions in the form of expectation, a novel algorithm is developed based on the recently proposed cooperative stochastic approximation (CSA). Simulation results show that the proposed algorithm can significantly improve the average network throughput, especially when the outage constraint becomes loose or the aggregation degree of users increases.