Performance of Non-Line-of-Sight Underwater Optical Wireless Communications

Underwater optical wireless communications (UOWC) offers higher data rates, lower latency and high bandwidths for underwater communications. However, UOWC systems suffer from significant scattering and absorption introduced by the channel and may also be blocked by countless obstructions and obstacles under the water. Thus, in this paper, the characteristics of a non-line-of-sight (NLOS) UOWC link with multiple scattering based on Monte Carlo simulation is considered. We address the channel response with different channel modulation schemes, include variation in the receiver field of view (FOV) and then proceed to evaluate the bit error rate (BER) and throughput of the system. In addition to a range of modulation methods, variation in the receiver bandwidth is also included. It is seen that distances over 80 meters are possible, providing BER values of 10−4 or better and throughput of 2.1 Mbps. This demonstrates that NLOS-UOWC offers a route to transmission at higher speeds than incumbent technologies in areas such as inshore environmental monitoring or oil exploration.