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Enhancing the bit error rate of indoor visible light communication systems using adaptive channel estimation algorithm

In this study, the authors propose an adaptive channel estimation algorithm for asymmetrically clipped optical orthogonal frequency-division multiplexing visible light communication (VLC) systems and analyse its optimal signal-to-noise ratio (SNR) threshold through the simulation experiments. The novel estimation scheme combines the advantages of orthogonal matching pursuit algorithm and least-square discrete Fourier transform algorithm. It is robust to the changes in channel distribution and SNR range. The performance for a VLC system using 16-quadrature amplitude modulation is presented in terms of mean square error (MSE) and uncoded bit error rate. In the high SNR range, the proposed scheme improves the MSE up to more than 10 dB.