1 / 2018-03-17 09:18:52

Optical Sigle Carier-Interleaved Frequency Division multiplexing for Visible Light Communication System

SC-IFDMA; PAPR; visible light communications

Abstract: In this paper, a novel optical single carrier- interleaved frequency division multiplexing (OSC-IFDM) signaling scheme for intensity modulation and direct detection (IM/DD) based visible light communications (VLC) system is presented. The OSC-IFDM significantly improves the peak to average power ratio (PAPR) of the DC-biased optical orthogonal frequency division multiplexing (DCO-OFDM). The reduction in the PAPR value is achieved by exploiting the symmetrical characteristics of the single carrier-interleaved frequency division multiple access (SC-IFDMA) time domain symbol whereby the imaginary and real parts of the SC-IFDMA samples are separated and transmitted through two sub-symbols. Simulation results show that the PAPR of the proposed scheme is 10 dB lower than that of the DC-OFDM scheme. Unlike the traditional DCO-OFDM scheme, the first subcarrier in OSC-IFDM is non zero and can be affected by the DC-bias, which will subsequently affect all OSC-IFDM samples in the time domain. However, a simple estimation algorithm is used in this work to remove the effect of the DC-bias at the cost of the required signal to noise ratio (SNR).