Receiver-Oriented Spatial Modulation in Visible Light Communication System

In this paper, we propose a receiver orientation model for spatial modulation (SM) in a visible light communication (VLC) system with line-of-sight (LOS) characteristics. The proposed technique efficiently mitigates the optical channel correlations across the multiple light-emitting diodes (LEDs), which are utilized in the SM system transmitter by altering the orientations of a photodiode (PD). Specifically, we express the LOS channel coefficients in the form of a PD normal vector and solve the optimization problems to obtain the optimal PD normal vectors. The bit error rate (BER) and channel capacity performances are also presented to validate the advantages of the proposed methods. The results demonstrate that the proposed designs offer a relatively low BER and high channel capacity in various LOS locations.