Fast-adaptive color-collaborative constellation designs for multicolor multiple-input multiple-output visible light communications systems.

A fast-adaptive color-collaborative signal constellation (CCSC) is proposed for chromaticity-changeable multicolor multiple-input multiple-output (MIMO) visible light communications (VLC) systems. The design of CCSC aims at developing the constellation to minimize the average optical power with shaping-based lattice code. For multicolor VLC signals, we arrive at the fact that the optimum shape of the constellation bounding region is an inequilateral N-D simplex.

Efficient signal design and optimal power allocation for visible light communication attocell systems.

In this paper, we investigate visible light communication (VLC) attocell systems in which any two neighboring attocells overlap. An efficient signal design for VLC called time superposition reuse (TSR) is proposed to mitigate interference and improve spectral efficiency. In the scheme, two neighboring cells are allocated with two time slots that have superposition in the time domain.