Journal of Innovation in Electronics and Communication Engineering

In this paper, an analytical approach is made for direct line of sight (LOS) underwater optical link configuration's performance. The performance is evaluated simulating the bit error rate (BER) of a single channel underwater wireless optical communication (UWOC) system deploying various modulation techniques. To ensure minimum attenuation, 532nm is selected as transmission wavelength. From the performance comparison among different avalanche photodiode (APD) receiver, Si APD is used in the receiver section to serve the purpose of optoelectronic conversion. The BER performance of direct line of sight (LOS) link configuration in underwater is observed for different water types e.g., pure sea water, clear ocean water, and coastal ocean water. In this analysis, the best performance is offered by 4-QAM technique in pure sea water. 4-QAM also allows maximum transmitter-receiver misalignment in pure sea water.