Performance Evaluation of Multipath VLC Links for Different Transmitter Configurations

Visible light communication (VLC) is an optical wireless communication technology in which light-emitting diodes (LEDs) used for illumination are also used for communication. Due to its numerous advantages, it is being actively researched for implementation in 5G cellular systems. In VLC, signals from transmitter panels can reach the receiver through numerous paths because of the reflections from walls. Consequently, these signals suffer from time dispersion, thereby imposing an upper limit on the achievable data rate. This time dispersion depends on a number of factors like wall reflectivity, receiver location, transmitter position, detector area, LED semiangle etc. So, there is a need to include the effect of multiple reflections (occurring in the practical indoor environment) in the performance evaluation of indoor VLC link. We obtain various channel parameters like mean excess delay, RMS delay, coherence bandwidth etc. by simulations in MATLAB to characterize the multipath channel for different transmitter configurations. We also study the error performance of the multipath VLC system in the presence of inter symbol interference (ISI). Moreover, we analyze the effect of LED semiangle on the channel characterization and error performance of multipath VLC links.