Going beyond 4 Gbps data rate by employing RGB laser diodes for visible light communication

Abstract

With increasing interest in visible light communication, the laser diode (LD) provides an attractive alternative, with higher efficiency, shorter linewidth and larger bandwidth for high-speed visible light communication (VLC). Previously, more than 3 Gbps data rate was demonstrated using LED. By using LDs and spectral-efficient orthogonal frequency division multiplexing encoding scheme, significantly higher data rates has been achieved in this work. Using 16-QAM modulation scheme, in conjunction with red, blue and green LDs, data rates of 4.4 Gbps, 4 Gbps and 4 Gbps, with the corresponding BER/SNR/EVM of 3.3 × 10⁻³/15.3/17.9, 1.4 × 10⁻³/16.3/15.4 and 2.8 × 10⁻³/15.5/16.7were obtained over transmission distance of ~20 cm. We also simultaneously demonstrated white light emission using red, blue and green LDs, after passing through a commercially available diffuser element. Our work highlighted that a tradeoff exists in operating the blue LDs at optimum bias condition while maintaining good color temperature. The best results were obtained when encoding red LDs which gave both the strongest received signal amplitude and white light with CCT value of 5835K.

32 Gigabit-per-second Visible Light Communication Link with InGaN/GaN MQW Micro-photodetector

“…Various modulation techniques have been investigated in VLC links, such as on-off keying (OOK) and orthogonal frequency-division multiplexing (OFDM) [10, [33][34][35][36][37][38]. OFDM has attracted attentions due to its robustness against inter-symbol interference (ISI) and frequency selective fading.…”

2 Gbit/s data transmission from an unfiltered laser-based phosphor-converted white lighting communication system

“…High-speed blue LDs can potentially be suitable for plastic optical fibers (POFs) based low-speed and shortdistance communications [23]. In addition to the modulation speed, a narrow emission spectrum of 2~3 nm allows wavelength-division multiplexing (WDM) as well as OFDM in red-green-blue (RGB) lasers for white light communication [24,25].…”

First demonstration of orange-yellow light emitter devices in InGaP/InAlGaP laser structure using strain-induced quantum well intermixing technique

“…2 Allowing multiple wavelengths to be used will increase VLC bandwidth and visible lasers with GHz modulation bandwidth can replace the slow modulation rate of LED technology.…”