A Double-Layer VLC System With Low-Complexity ML Detection and Binary Constellation Designs

We consider a double-layer visible light communication system where transmitted data is split into two layers with different priorities and variant transmission rates. High-priority data is assigned to the upper layer with low transmission rate, while low-priority data is assigned to the lower layer with higher transmission rate. For this scenario, we develop a low-complexity maximum likelihood detection algorithm. In addition, several binary constellation designs corresponding to different priority orders are presented. Computer simulations show that maximum likelihood detection detection significantly improves the error-rate performance, compared to sum detection, without compromising the computational complexity of the receiver.