Channel equalization based on QR decomposition in indoor visible light communication

In this paper, we propose a QR decomposition based channel equalizer in visible light communication (VLC) systems for indoor broadband wireless access to overcome the bandwidth limitation of phosphor-coated white light emitting diodes (LEDs). The effectiveness of the proposed QR decomposition based channel equalizer is experimentally investigated in a 400-Mb/s VLC system over 1.6-m air transmission with discrete multi-tones (DMT) modulations and discrete Fourier transform (DFT) spreading. Compared with conventional channel equalizers for DMT modulations, the QR decomposition based channel equalizer can combat the limited bandwidth of phosphor-coated white LEDs and achieve much better transmission performances.