Efficient resource allocation scheme for dually connected non-orthogonal multiple access based LIFI-RF networks

Light fidelity (LiFi) is a pioneering technology that incorporates high-speed wireless communication and illumination by using light-emitting diodes. Despite the fact that LiFi technology cannot replace radio frequency (RF) communication completely, it is preferable for indoor networks because of its high data rates, minimal RF interference, and low implementation costs. Although RF technology is known for its slow data transmission speeds, its access points can effectively cover a large area. Therefore, it is of utmost importance to integrate both RF and LiFi technologies to fully leverage the advantages of each, resulting in an enhanced system performance. A novel solution to integrate LiFi and RF access points is presented in this paper, which aims to improve users' data rates by setting access point selection criteria and the ability for users to switch to alternate access points. One of the crucial factors for selecting access points for users is the signal to noise and interference ratio (SINR). If a user's SINR falls below a specified threshold, they are allowed to switch immediately to alternative access points. This criterion ensures that the users experience minimal interference and noise, leading to improved data transmission rates. The performance of the dual system is analyzed using MATLAB Monte Carlo iterations, and the simulation results indicate that the proposed approach achieves a total sum rate of 2.2x109\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$2.2 \times 10<^>{9}$$\end{document} bps, which is higher than the sum rates of individual LiFi and RF systems at 1.9x109\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$1.9 \times 10<^>{9}$$\end{document} bps and 0.6x109\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$0.6 \times 10<^>{9}$$\end{document} bps respectively. In conclusion, the proposed approach exhibits a substantial improvement in the total sum rate, increasing it by 72.2% from individual RF and by 13% from individual LiFi. This indicates that the combined system achieves significantly elevated data transmission rates, thereby increasing overall efficiency and providing better service to end-users. The results of the study demonstrate the effectiveness of the integration of LiFi and RF access points, which can have a significant impact on the future of wireless communication and networking.