Unidirectional Visible Light Communication and Illumination With LEDs

Visible light communication (VLC) with light emitting diodes (LEDs) has attracted interest for interactive and networked lighting control, and consumer infotainment applications. In this paper, we propose an LED system for jointly achieving unidirectional VLC while providing flicker-free illumination. At the transmitter, a redundant run-length limited encoding scheme and multi-level dimming is considered for data transmission, with a wide dimming range. The receiver uses ON-OFF keying and uses the OFF periods for VLC reception. It is allowed to be asynchronous to the transmitter, with a phase offset within a preset range. A key feature of the proposed system is that no dedicated devices are used for transmission/reception, with the LEDs used for these functions. We design a functional prototype of this system and evaluate the communication bit error rate and illumination flicker performance experimentally.