User-centric quality of experience optimized resource allocation algorithm in VLC network with multi-color LED.

Visible light communication (VLC) can provide indoor illumination while achieving high network throughput. In order to mitigate the performance degradation caused by inter-cell interference (ICI) and support multiple users, this paper utilizes the white LED synthesized by multi-color light sources as indoor illumination and signal transmissions. Compared with ordinary LEDs, multi-color LEDs not only has excellent color rendering index, but also realize multi-channel parallel transmission, which greatly improves the transmission speed of VLC. Meanwhile, we propose a user-centric (UC) quality of experience (QoE) optimization scheduling scheme for the VLC down-link system. In contrast to the traditional network-centric (NC) design, the UC scheme is based on the user-centric dynamic construction and adjustment of the network model. Furthermore, in order to further analyze the performances of the illuminations and signal transmissions of the VLC system with multi-color LED, we consider the system model under two scenarios of 3-color and 4-color synthetic white LEDs. For these two different LED composition and optimization problems, we design a new greedy algorithm to allocate optical bandwidth, and dynamically searched for the optimal access point user equipment (AP-UE) link based on optimization of the UEs' QoE values. In order to analyze the robustness of the algorithm, we further consider the influences of UEs on the transmission performance under different UEs' spatial distributions, e.g., uniform and Poisson distributions. The simulation results illustrate that the proposed scheme guarantees the UEs' QoE while offering illumination quality. Meanwhile, compared to ordinary LEDs and the traditional network-centric (NC) design, our proposed scheme can schedules more UEs.