Visible-Light Multi-Gb/s Transmission Based on Resonant Cavity LED With Optical Energy Feed

Abstract

Multi-Gb/s visible-light communication is demonstrated using a commercial off-the-shelf resonant-cavity light emitting diode (LED), which is originally rated for 150 Mb/s. By applying analog frequency response equalization and multi-carrier modulation schemes, a transmission capacity of up to 4.3 Gb/s is obtained over a single wavelength in a close-proximity scenario. Nyquist-shaped multi-band modulation and orthogonal-frequency-division multiplexing are applied with high spectral sub-carrier efficiencies of up to 8 b/symbol. The transmission rate is experimentally investigated as a function of the loss budget and further related to link reach based on free-space measurements under clear weather conditions. Analog signal transmission is also validated using real-time signal (de-)modulation with a high-definition video payload. We further demonstrate that on/off keying in combination with simpler baseband modulation can be facilitated for data rates of up to 750 Mb/s. This proves that commercially available LEDs can serve as a versatile low-cost transmitter. Finally, the joint transmission of energy and data has been validated. A power feed with an irradiance of 240 W/m2 is experimentally shown to enable a remotely supplied optical burst receiver for periodic access to Gb/s data rates.