Energy-Efficient Adaptive MIMO-VLC Technique for Indoor LiFi Applications

A simple adaptive method is proposed for multiple-input-multiple-output (MIMO) visible light communication (VLC) to increase the energy efficiency. Based on channel conditions, the desired spectral efficiency and a target error rate, the MIMO technique is chosen from three possible choices: repetition coding (RC), spatial multiplexing (SMP) and a modified version of spatial modulation (SM). At each location, the MIMO technique with a smaller input energy requirement is chosen, and thus the energy consumption is reduced. Such an adaptive method can be significantly beneficial in applications such as Internet-of-things (IoT) where energy consumption is a critical factor.