Performance Analysis of DST-Based Intensity Modulated/Direct Detection (IM/DD) Systems for VLC

Abstract

The dual functionality of assuring ‘illumination’ and “communication” contemporaneously by relying on sustainable and energy-efficient opto-electronic devices like light emitting diodes (LEDs) has enabled visible light communication to garner the attraction of research era. This paper proposes a discrete sine transform (DST)-based optical orthogonal frequency division multiplexing (OFDM) system bestowing as the simplest and alternative multicarrier scheme complying the requirements of intensity modulated and direct detection systems. Moreover, this paper addresses the most vital issue like peak to average power ratio (PAPR) that emerges principally due to the limited dynamic range of LEDs when exploiting DC-biased optical OFDM (DCO-OFDM). Therefore, this paper imparts DST spreading to DST-based DCO-OFDM (DST-S-DCO-OFDM), and consequently, the PAPR performance is compared with other PAPR reduction schemes for the same system. Furthermore, in order to serve multiple subscribers with high-data rates as well as to significantly reduce the amount of PAPR of the multicarrier system, this work investigates a DST-based single carrier frequency division multiple access (DST-SC-FDMA) and derives the mathematical analysis of the time-domain signal formats for different subcarrier mapping strategies like DST-based optical interleaved frequency division multiple access (DST-OIFDMA) and optical localized frequency division multiple access (DST-OLFDMA). The simulated results evidences that the reduction in PAPR for DST-S-DCO-OFDM is more predominant when compared with other PAPR reduction schemes and among the multiple access schemes, the DST-OIFDMA is more power efficient upon comparison with DST-OLFDMA. However, both the schemes exhibit a significant reduction in PAPR when compared with DST-based optical OFDM (DST-OOFDMA).