Optimized DFT-spread OFDM based visible light communications with multiple lighting sources.

Discrete Fourier transform spread orthogonal frequency-division multiplexing (DFT-S-OFDM) has demonstrated its capability in reducing peak to average ratio (PAPR), while maintaining reliable transmissions. This paper investigates the application of DFT-S-OFDM technology in visible light communications (VLC), and reveals the mechanism on how a multiple lighting distributed layout affects its performance. In addition, an optimization approach of lighting layout is proposed through making a trade-off between the strong interfered areas and the maximum delay spread inside. Eventually, a Gbit/s DFT-S-OFDM based multiple lighting VLC downlink prototype is achieved for the first time in the form of real-time baseband modem and compact size components.