High-Flux VLC Emitters with Spectrally Tailored LED Drive in Support of Simple Baseband Signaling

Visible light communication (VLC) is an attractive way to integrate data exchange in systems that are merely dedicated to lighting. As the arguably most abundant luminaire, the light emitting diode (LED) can contribute to this challenge as a low-cost light emitter. A multi-faceted approach is evaluated to overcome its intrinsic bandwidth/flux trade-off, including analogue equalization, spectral stitching and incoherent beam combining. An optical link budget of 33 dB is found to be compatible at 100 Mb/s data rate, as it is evidenced through low-latency Ethernet-over-VLC transmission over medium- and high-flux (>50 lm) LEDs, proving further that a sub-20 lm LED can cater for the real-time point-cloud transmission over a 100-m out-door VLC link. The migration to Gb/s-class VLC rates is accomplished through laser-based emitters and a strongly pre-equalized LED drive. The results reveal that broadband modulation with simple data coding still prevails over distortion-sensitive modulation, while analogue pre-equalization techniques for 1-Gb/s transmission over low-complexity LED emitters are required to enter a costly trade-off between wideband support and a highly reduced optical link budget.