ACO-OTFS and ADO-OTFS for Indoor Relay-Assisted Visible Light Communication

Orthogonal time frequency space (OTFS) is a promising two-dimensional modulation scheme outperforming orthogonal frequency division multiplexing (OFDM) on both dynamic and static multipath channels. However, there are still few efforts for optical OTFS and its performance evaluation in visible light communication (VLC). In this paper, we propose asymmetrically-clipped optical OTFS (ACO-OTFS) scheme for VLC. Based on ACO-OTFS and existing direct current biased optical OTFS (DCO-OTFS), we further propose asymmetrically clipped direct current biased optical OTFS (ADO-OTFS). We evaluate the bit error rate (BER) performance of both proposed schemes and the influencing factors of ADO-OTFS on relay-assisted multipath channels. Numerical results have shown that the BER performance of ACO-OTFS is much better than that of DCO-OTFS and the power efficiency of ADO-OTFS is higher than that of DCO-OTFS at high data transmission rates. Therefore, ADO-OTFS is more suitable for high data rate transmission scenarios by appropriate parameter setting.