Enabling real-life deployment of piggyback-VLC via light emission composition

Abstract

Whereas the increasing popularity of both commercial light-emitting diode (LED) lighting and mobile devices certainly creates opportunity for real-life deployment of visible light communication (VLC) systems, reaching the high throughput promised by lab experiments still faces major obstacles. In particular, lacking the sophisticated hardware and software support under experimental conditions, real-life systems are challenged in many aspects, especially low signal-to-noise ratio, low operation frequency, uncontrollable LED nonlinearity, and illumination requirements. Nonetheless, deployments tapping commercial infrastructure are critical to gain market penetration for VLC-enabled wireless applications, so boosting the performance of these real-life systems becomes imperative. In this article, we consider the multiple LED chips and/or light sources nature of indoor commercial lighting infrastructure, and propose a spatial modulation that composes the cooperative light emissions (transmissions) from multiple LEDs. In addition to gaining a higher spectral efficiency, this scheme utilizes the multiple-LED nature of commercial lighting to overcome LED nonlinearity with a novel yet simplified hardware construction. We present two typical designs adopting this special modulation under different infrastructural constraints, and provide an introduction on its potential contribution to the standardization of VLC. Finally, we discuss potential extensions to further improve performance.