M-CSK moduled flip-OFDM communication systems in visible light communications

In this paper, it is proposed to use M-level color shift keying (M-CSK) modulation without vibration problem in Flip-OFDM waveform, which is an efficient unipolar version of OFDM for optical wireless communication systems. The performance of the proposed scheme is compared with the M-QAM modulated Flip-OFDM and M-CSK-modulated VLC OFDM methods based on the criteria of bit-error-rate (BER) and peak average power ratio (PAPR). The BER performance has also been analyzed, firstly by using uncoded proposed scheme then two channel coding techniques i.e.Reed-Solomon (RS) channel encoder and Convolutional Codes (CC) by using two channels i.e. AWGN and optical LOS channel. The entire channel coding techniques is carried out using QAM modulation. The simulation results show that, the proposed M-CSK Flip-OFDM method achieves good performance at high SNR values for both AWGN channel and optical LOS channel and also with applying RS and CC, the BER performance is also improved.