Optimization of Channel Assignment and Access Point Transmit Power for Minimizing Contention in Wireless LANs

We study the problem of optimizing AP configuration in wireless LANs. In particular, we address the issue of simultaneous planning and optimization of access point (AP) transmit power and channel assignment in the network. We aim at improving network performance in terms of reduced contention in the network by controlling the coverage range of APs and minimizing adjacent channel interference. One of the advantages of our model is that it is not limited to a case when only non-overlapping channels are considered but allows us to deal with any channel set that may also include overlapping adjacent channels. By our model, a higher priority is given to solutions in which neighboring APs with large overlapping coverage areas have larger channel distance. Numerical solutions are compared to a reference network configuration with fixed uniform AP power levels and a channel assignment minimizing coverage overlap of APs operating on the same channel. Our numerical experiments demonstrate that AP transmit power control jointly optimized with the channel assignment can significantly improve network performance in terms os contention and interference distribution.