Optimized Multi-Primary Modulation for Visible Light Communication

Multi-primary modulation scheme has the potential to provide robust visible light communication links and mitigate any color fluctuations by providing identical chromaticity modulation alphabets. This work describes constellation optimization technique for multi-primary modulation (MPM), which shows that using different power levels for the primary lights can lead to obtain the same color and, furthermore, enhance the Euclidean distances between data symbols in the multi-dimensional color space. The bit error rate performances of the optimized MPM and the original non-optimized MPM schemes are evaluated considering indoor optical wireless channel models with additive white Gaussian noise. The results show that the optimized MPM provides better spectral efficiency and outperforms the original non-optimized MPM scheme by achieving up to 3.5 dB Signal-to-noise ratio gain for the same spectral efficiency and, therefore, opens doors for implementation of robust visible light communication links exploiting multi-color light sources.