Effect of Variable LED Rise Time on High Speed OOK Underwater Visible Light Communication System

Underwater visible light communication (UVLC) system emerges as an optimistic technique to improve the capacity of underwater wireless communication networks for future generation. In emerging underwater visible light communication system, Light-emitting diodes (LEDs) are broadly used for information transmission. In this paper, we investigate the effect of rise time of LED that limit the bandwidth and cause non-linearities in the light output of highly efficient LEDs. In this paper, performance comparison among wide range of rise time of LED in UVLC system is presented for PIN and Avalanche photodiode. The effect of using variable LED rise time on the bit-error rate, signal-to-noise ratio, communication link distance is also studied. OptiSystem is used to implement the UVLC system. Finally, it is shown in the paper that as the rise time of LED decreases, performance of high speed underwater visible light communication system increases.