Performance Improvement of White LED-Based VLC Systems Using Blue and Flattening Filters

This paper proposes a means to maximize the data rate supported by a visible light communication (VLC) system. The investigated VLC system uses phosphor-coated white light emitting diodes (LEDs), which are common in existing illumination systems but are also known to limit the communication system's data rate. In this paper, we propose a remedy to such a limitation by adding a response-flattening filter at the receiver's end to mitigate the effect of the slow yellow phosphor spectral component. An experimental study is conducted to evaluate the validity of the proposed remedy. The resulting performance is compared with an existing remedy that involves adding a blue filter at the receiver. Off-the-shelf commercial filters are used in the experiment. Enhanced bit-error-rates (BERs) and signal-to-noise ratios (SNRs) at high data rates are observed. Specifically, our experimental work demonstrates that BER is enhanced by 40% and 15% for data rates up to 12 Mbps when responseflattenina filter and blue filter are adopted, respectively.