The main limitation of visible light communication (VLC) is the narrow modulation bandwidth, which reduces the achievable data rates. In this letter, we apply the nonorthogonal multiple access (NOMA) scheme to enhance the achievable throughput in high-rate VLC downlink networks. We first propose a novel gain ratio power allocation (GRPA) strategy that considers the users' channel conditions to ensure efficient and fair power allocation. Our results indicate that the GRPA significantly enhances the system performance compared with the static power allocation. We also study the effect of tuning the transmission angles of the light emitting diodes and the field of views of the receivers, and demonstrate that these parameters can offer new degrees of freedom to boost the NOMA performance. The simulation results reveal that NOMA is a promising multiple access scheme for the downlink of VLC networks. Index Terms-Multiple access, NOMA, power allocation, power domain multiple access, visible light communication.
For multiple APs, the work in REF proposes a gain ratio power allocation (GRPA) method and compares it with the fixed power allocation method, when the users' movement model follows the random walk model.
Non-Orthogonal Multiple Access for Visible Light Communications
IEEE Photonics Technology Letters
IEEE Photonics Technology Letters
Physics Computer Science Mathematics