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Hybrid space-frequency domain pre-equalization for DC-biased optical orthogonal frequency division multiplexing based imaging multiple-input multiple-output visible light communication systems

Abstract. We propose a hybrid space-frequency domain pre-equalization technique for indoor multiple-input multiple-output visible light communication (MIMO-VLC) systems using DC-biased optical orthogonal frequency division multiplexing with an imaging receiver. The proposed hybrid space-frequency domain pre-equalization is jointly performed in both space and frequency domains for the purpose of achieving comparable signal-to-noise ratio performances of different channels in an imaging MIMO-VLC system. It is shown by the simulation results that a four-channel imaging MIMO-VLC system with a raw data rate of 1.2  Gb/s using hybrid space-frequency domain pre-equalization achieves significantly improved bit error rate performance than the system using only frequency domain pre-equalization, resulting in up to 52.6% improvement in communication coverage area at a target BER of 10–3.