Optimal Power Allocation Scheme Based on Multi-Factor Control in Indoor NOMA-VLC Systems

Abstract

In order to overcome the limitation of narrow modulation bandwidth on the performance in the visible light communication (VLC) systems, non-orthogonal multiple access (NOMA) is applied to the downlink VLC networks in this paper to improve the sum rate performance effectively. We first propose an optimal power allocation strategy which is based on the multi-factor control (MFOPA), aiming to maximize the total system capacity subject to ensuring all users' quality of service (Qos) and fairness, as well as illumination requirements. The analytical results indicate that the proposed MFOPA could provide higher system sum rate and better user fairness as well as guarantee the Qos and eye safety of each user at the same time when compared with the static power allocation (SPA) and gain ratio power allocation (GRPA) schemes, especially in high demand for signal-to-interference-plus-noise ratio (SINR). What is more, considering the residual interference may exist during the successive interference cancellation (SIC) at the receiver, namely imperfect SIC, the interference cancellation factor is also taken into account in MFOPA strategy. The numerical results are shown to demonstrate the robustness and effectiveness of the MFOPA in NOMA-VLC when the residual interference remains. INDEX TERMS Visible light communication (VLC), non-orthogonal multiple access (NOMA), power allocation, multiple factors, imperfect successive interference cancellation (SIC).

A Survey of NOMA for VLC Systems: Research Challenges and Future Trends

“…The sum rate performance of the proposed multifactor control optimal power allocation (MFOPA) outperforms FPA and GRPA [66] 4 VLC AP + K users KKT conditions for optimality Sum rate…”

Performance analysis of a low-complexity nonorthogonal multiple access scheme in visible light communication downlinks using pulse modulations

“…Fu et al proposed an enhanced power allocation algorithm to maximize the sum of data rates and minimize the subcarrier loss rate of the system by considering user-and subcarrier-level power allocation in OFDM-based NOMA-VLC systems [18] . Li et al proposed an optimal power allocation strategy based on multi-factor control for an indoor NOMA-VLC scenario with multiple users, aiming to maximize the total system capacity subject to the Quality of Service (QoS) requirement, fairness, and eye security of each user simultaneously [19] . By taking the power line as a backbone feed for VLC systems, Feng et al proposed a joint PLC-VLC power allocation strategy to maximize the sum throughput of a PLC-VLC network [20] .…”

On The Selection of Power Allocation Strategy in Power Domain Non‐Orthogonal Multiple Access (PD‐NOMA) for 6G and Beyond

“…45 In literature, few works compared DPA numerical search methods with DPA strategic design methods and FPA techniques. For example, FTPA was compared with iterative gradient-based power allocation in the work of Zhang et al 46 In the works of Liu et al 47 and Li et al, 48 GRPA and arbitrary FPA were compared with power allocation based on the Lagrange multipliers method and power allocation based on the standard interior point method, respectively.…”