Multi-band orthogonal circulant matrix transform precoding over visible light communications

摘要

We propose and experimentally demonstrate a novel channel-independent multi-band orthogonal circulant matrix transform (MB-OCT) precoding, to efficiently combat the severe frequency-selective fading induced by the limited modulation bandwidth of visible light communication (VLC). The proposed MB-OCT precoding exhibits ladder-like signal-to-noise-ratio (SNR) profile, thus significant BER reduction can be achieved by applying different quadrature amplitude modulation (QAM) level to different sub-band. The impacts of sub-band number and system bandwidth on bit error rate (BER) of the VLC system are investigated. Experimental results show that for ~700-Mb/s VLC system with 2-m transmission distance, the BER performance can be improved from 1.53×10-2 to 1.17×10-4 by using the proposed MB-OCT precoding.