16 Gbps visible light communication using a high-fidelity illumination white light source based on RGBY four-wavelength division multiplexing

In this paper, we present a high-speed visible light communication (VLC) system utilizing a high-fidelity white light source based on red, green, blue, and yellow (RGBY) four-wavelength division multiplexing (WDM). The proposed white light source integrates red, green, and blue laser diodes (RGB LDs) with a yellow diode-pumped solid-state laser (Y-DPSSL) to achieve simultaneous illumination and data transmission. A total transmission capacity of 16 Gbps is achieved by encoding the RGB LDs via 16 quadrature amplitude modulation discrete multitone modulation (16-QAM DMT) data. The received bit error rates (BERs) are 1.6 × 10^-4 for the red LD, 1.1 × 10^-4 for the green LD and 2.9 × 10^-3 for the blue LD, all of which are less than the forward error correction (FEC) threshold of 3.8 × 10^-3. To address the demand for high-fidelity illumination, the Y-DPSSL in the white light source is switched on to provide yellow-orange luminescence and then fill the red-green spectral gap. By adjusting the power ratio of RGBY lasers, a white light with a correlated color temperature (CCT) of 4195 K, a color rendering index (CRI) of 82.4 and Commission Internationale de l'Eclairage (CIE) coordinates of (0.3784, 0.3976) is obtained. These values are superior to the currently reported tricolor-laser-based white light source for illumination. This work paves the way toward the technological development of high-fidelity white light illumination while simultaneously achieving high-speed VLC.