User-Centric Cell Formation for Blind Interference Alignment in Optical Wireless Networks

Visible light communication (VLC) is considered a promising technology for providing high data rates in indoor environments. In this sense, each optical access point (AP) in a VLC network can be managed as a small cell usually referred to as attocell. Therefore, the received signal is subject to both multi-user interference (MUI) and inter-cell interference (ICI). In this work, we propose a user centric (UC) cell formation approach jointly with the use of blind interference alignment (BIA) in order to manage the interference. We formulate an optimization problem based on maximizing the sum utility of users rates for the sake of jointly finding the optimal cell formation and minimizing the limitations of BIA, i.e., the noise enhancement and the required coherence time given by the mobility of the users. This problem can be solved through exhaustive research, which involves an unpractical complexity. After that, we decouple the main problem into two sub-problems that may be solved separately. The simulation results show that the proposed schemes are more suitable for VLC networks than the considered benchmark schemes.