Analysis on the performance of normalised gain difference power allocation for MIMO-NOMA-based VLC

Abstract

In this study, we build a 4 × 4 multiple-input multiple-output (MIMO) non-orthogonal multiple access (NOMA) based visible light communication (VLC) system. The main goal of this study is to optimise the power consumption on the indoor VLC system by using normalised gain difference power allocation (NGDPA) to ensure the same achievable sum rate even for users on the system borders. The proposed system is simulated to serve 2, 3, and up to 4 users. The obtained results were compared with 4 × 4 MIMO using NOMA without applying NGDPA. It was found that the proposed system shows an almost constant achievable sum rate for all users regardless of their current position within the system coverage area. The results show that users on the system edge can share up to 97.32% of the maximum achievable sum rate. The relation between normalised offset and sum rate gain for 2, 3, and 4 users' scenarios is also discussed. The findings revealed that the system using NOMA with NGDPA scheme can utilise more sum rate gain with increasing the number of users. Through this study, it can be deduced that the 4 × 4 MIMO-NOMA-VLC system with NGDPA scheme has been performance.