An advanced A-law companding algorithm in VLC-OFDM

In visible light communication (VLC) systems, the employing of orthogonal frequency division multiplexing (OFDM) may produce nonlinear distortion, due to the nonlinear characteristics of LEDs and the high peak to average power ratio (PAPR) of OFDM. Moreover, the clipping block deteriorates the distortion. In this paper, an advanced A-law algorithm for alleviating such distortion in VLC-OFDM systems is proposed. Simulation result shows that the BER of VLC-OFDM systems can be obviously reduced by employing the advanced A-law algorithm with suitable companding parameters, compared with the original VLC-OFDM process.