Color Space and Multi-stream Spatial Modulation based Indoor Visible Light Communication

Abstract

In this paper, we propose a color space and multi-stream spatial modulation (CS-MSM) based visible light communication (VLC) system to improve both the system spectral efficiency and the symbol error rate (SER), which exploits the color index and also the spatial index of the quad-LED (QLED) to convey information bits. We first take the multi-stream spatial modulation (MSM) scheme to select the QLED indexes based on the channel correlation. Then, spatial modulation (SM) is further employed in the color index selection for each QLED to increase the information bit rate of the VLC system. Finally, an analytical SER upper bound of the proposed CS-MSM scheme is derived. Numerical results and analysis verify that the CS-MSM based VLC system outperforms the other SM based VLC systems significantly. Moreover, the effect of the half-power semi-angle of the QLEDs on the system performance has also been discussed.