Application of Expurgated PPM to Indoor Visible Light Communications-Part I: Single-User Systems

作者：Noshad Mohammad^*; Brandt Pearce Maite

来源：Journal of Lightwave Technology, 2014, 32(5): 875-882.

DOI：10.1109/JLT.2013.2293341

• Expurgated pulse position modulation (EPPM)
• indoor optical wireless communications
• optical networks
• visible light communications

Visible light communications (VLC) in indoor environments suffer from the limited bandwidth of LEDs as well as from the inter-symbol interference (ISI) imposed by multipath. In this work, transmission schemes to improve the performance of indoor optical wireless communication (OWC) systems are introduced. Expurgated pulse-positionmodulation (EPPM) is proposed for this application since it can provide a wide range of peak to average power ratios (PAPR) needed for dimming of the indoor illumination. A correlation decoder used at the receiver is shown to be optimal for indoor VLC systems, which are shot noise and background-light limited. Interleaving applied on EPPM in order to decrease the ISI effect in dispersive VLC channels can significantly decrease the error probability. The proposed interleaving technique makes EPPM a better modulation option compared to PPM for VLC systems or any other dispersive OWC system. An overlapped EPPM pulse technique is proposed to increase the transmission rate when bandwidth-limited white LEDs are used as sources.

• 出版日期2014-3-1