Research On Indoor Visible Light Communication System Based On OFDM

The visible light communication (VLC) is a kind of optical wireless communication that uses the white LEDs. In VLC system, white LEDs are used not only as the illuminator in the rooms, but also as the source of the communication system. Thus it offers a novel broadband access way.In this paper, we analyze the channel characteristics of visible light communication at first, using Monte Carlo ray-tracing algorithms for the calculation of the impulse response on VLC channel, and present the simulation results. For the multipath dispersion in indoor diffuse optical wireless links, we investigate OFDM to reduce the intersymbol interference (ISI). In addition, the wireless optical channel is selectivity fading in frequency domain, so we investigate adaptive OFDM in our system. It can adaptively allocate appropriate modulation mode to each subcarrier according to sub-band quality, increasing the aggregate throughput. From the result of computer simulation, we can find that this approach is feasible for utilizing resource of the frequency band and improving whole performance of the system.In order to give a reference, we provide a hardware design plan at the end.