Convex Optimization Approach to Multi-Level Modulation for Dimmable Visible Light Communications under LED Efficiency Droop Lee, Sang Hyun; Park, Il-Kyu; Kwon, Jae Kyun;
This paper deals with a design method and capacity loss of an efficient multi-level modulation scheme for dimmable visible light communications (VLC) systems that use light-emitting diodes (LEDs) with efficiency droop. To this end, the impact of such an impairment on dimmable VLC is addressed with respect to multi-level modulations based on pulse-amplitude modulation (PAM) via data-rate optimization formulation.
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