Demonstration of a Variably Biased Asymmetrically Clipped Optical OFDM for VLC Systems

Asymmetrically clipped direct current (DC) biased optical orthogonal frequency division multiplexing (ADO-OFDM) is a recently emerged waveform in the visible light communication (VLC) to obtain the optimal solution for the spectral and power efficiency problems. However, in ADO-OFDM, high DC-bias is used to attain unipolar signals, which decreases the power efficiency. In this work, we conceive a novel modulation technique called variably biased asymmetrically clipped optical orthogonal frequency division multiplexing (VAO-OFDM) for VLC systems. In which the bias varies with respect to the amplitude of the specific samples, which results in power efficiency. Further, the performance of the VAO-OFDM system is evaluated using LabView software-based simulations and validated on the experimental setup by the VLC testbed using USRP hardware.