The Performance Analysis on Visible Light Communications Multi-LED Parallel Superposition High Speed Transmission

The transmission rate of visible light communications (VLC) remains low as the low modulation bandwidth performance of light emitting diode (LED). This paper proposes a transmission system consisting of multiple LEDs and a photodiode (PD) to increase the transmission rate. We combines the radio superposition coded modulation (SCM), interleave division multiple access(IDMA) technology with VLC. To fit the driving voltage non-negative characteristics of LED and detect the mixed multi-LED light intensity signals, the VLC multi-LED parallel transmission based on OOK modulation scheme is proposed, which has about K (K is the number LED wicks) times the transmission rate of the traditional ways. Finally, we analyze the number of iterations, the different specific interleaver and the driving voltages that are the factors influence the transmission performance. The simulation also verifies the high speed transmission capability and the anti-nonlinearity performance of the proposed scheme.