Analysis of energy saving ability in dimming VLC systems using LEDs with optimized SAHP

• The potential of LED SAHP oriented system parameters to enhance VLC energy efficiency is investigated.
• Four LED alignments of the same total LEDs are deployed and their performances are compared.
• Types of optimizations are designed to gain better tradeoff between efficiency and SNR variations.
• VLC with narrow SAHP LEDs can save more than 40% energy consumptions compared to the traditional dimming situation.

In this paper, we investigate the energy saving capability of dimming visible light communication (VLC) systems employing SC-4 PPM modulation scheme. We design different optimizations to maximize the energy efficiency according to the different illuminance efficiency with respect to LED's semi-angle at half power (SAHP) for four different LED alignments. Tradeoff between energy efficiency and signal-to-noise ratio (SNR) uniformity are also investigated to achieve better overall performance. The results show that more than 40% energy can be saved over the existing dimmed VLC system employing SC-4 PPM modulation scheme when optimized SAHP LEDs are used.