Hybrid NOMA-Based ACO-FBMC/OQAM for Next-Generation Indoor Optical Wireless Communications Using LiFi Technology

Abstract The light fidelity (LiFi) has been successfully used to achieve high data transfer rates, high security, great availability, and low interference. In this paper, we propose a LiFi system consisting of a combination of non-orthogonal multi-access (NOMA), asymmetrically-clipped optical (ACO) and filter bank multicarrier (FBMC) techniques combined with offset quadrature amplitude modulation (OQAM). The paper also applies a $\mu$-law companding approach for a high peak to average power ratio (PAPR) reduction of the FBMC/OQAM scheme. The combination of NOMA, ACO-FBMC/OQAM, and $\mu$-law companding allows a significant increase in throughput and a significant reduction in non-served users. An appropriate algorithm is developed considering two scenarios, maximize the throughput and minimize the number of blocked (non-served) users. The results show that the throughput of the system can be increased by $1.8$ compared to FBMC and OFDM. Furthermore, the proposed system reduces the number of blocked users below $10\%$, while the system can provide $30\%$ or $60\%$ in case only the FBMC or OFDM is used, respectively.