Comparative analysis of DIPPM scheme for Visible Light Communications

Visible Light Communications (VLC) uses solid-state light sources for data transmission in addition to its primary function of illumination. The dual functionality of light source provokes some challenges for VLC including dimming control and perceivable flicker mitigation. These challenges can be achieved by an appropriate modulation scheme. Double Inverse Pulse Position Modulation (DIPPM) scheme allows for both dimming control and flicker mitigation. This scheme modifies the symbol structure of Inverse Pulse Position Modulation (IPPM) scheme to obtain the symbol of DIPPM. The modification in IPPM symbol structure to obtain DIPPM symbol is explained with the mathematical model in this paper. Furthermore, the 2-DIPPM scheme is analyzed in terms of required power with respect to dimming factor and normalized bit rate respectively. Also, the required power for DIPPM is compared with VPPM.