Performance analysis of MIMO-NOMA-Based Indoor Visible Light Communication in Single Reflection Environment

This paper examines the performance of multiple-input-multiple-output (MIMO) non-orthogonal multiple access (NOMA) based indoor visible light communication (VLC) in a single-reflection environment. The VLC system is equipped with two light-emitting diodes (LEDs) transmitter and multi-user receiver, and each user consists of two photodiodes (PDs) working as a NOMA pair. In this paper, a single reflection scenario is considered, and the corresponding delay spread is calculated which is the function of room dimensions. The proposed approach uses two efficient power allocation methods namely normalized gain difference power allocation (NGDPA) and gain ratio power allocation (GRPA). Later, the measurable data rate and channel delay spread in MIMO with NOMA based VLC system is investigated using these methods. The result shows that NGDPA with NOMA has a percentage gain of sum rate up to 18.22 as compared to GRPA with NOMA. Furthermore, the numerical values of maximum channel delay spread are 10.89 ns and 11.14 ns in GRPA and NGDPA, respectively for two users.