Resource allocation in visible light communication networks: NOMA vs OFDMA transmission techniques

Abstract

Energy-efficiency, high transmission data rates and Quality of Service (QoS) awareness are the major challenges for resource management in the uplink of Visible Light Communication Personal Area Networks (VPANs). This paper investigates the problem of Optical Access Point (OAP) selection and resource allocation in the uplink of VPANs under two different transmission techniques, namely Orthogonal Frequency Division Multiple Access (OFDMA) and Non-Orthogonal Multiple Access (NOMA). Each user is associated with a generic utility function, which represents his perceived satisfaction with respect to the overall resource allocation problem. OAP selection adopts Maximum Gain Selection (MGS) policy, i.e. users select an OAP to connect to based on the highest path gain. A distributed resource allocation problem in VPANs is formulated and solved as an optimization problem. Following this analysis, a decentralized iterative and low-complexity algorithm for determining OAP selection and resource allocation is proposed, while the overall approach’s efficiency is illustrated via modeling and simulation, highlighting and assessing the advantages and drawbacks of each adopted transmission technique, i.e. OFDMA and NOMA.