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arXiv · 1309.0750

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

Mohammad Noshad·Maite Brandt-Pearce
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Abstract

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-position modulation (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.

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Mohammad Noshad, Maite Brandt-Pearce. 2013-09-03. Application of Expurgated PPM to Indoor Visible Light Communications - Part I: Single-User Systems. https://doi.org/10.1109/jlt.2013.2293341

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