Underwater Wireless Optical Communications: From the Lab Tank to the Real Sea

Underwater wireless optical communication (UWOC) is a competitive candidate for ocean information transmission due to its high bandwidth and low latency. UWOC has already achieved transmission distances of more than hundreds of meters with data rates of several hundred Mbps, showing great potential in applications such as high-definition video transmission and sensor network data collection. In this paper, we review the recent progress in transceivers and signal processing techniques to build long-distance UWOC systems. Besides, solutions to the turbulence and misalignment are introduced to illustrate the robustness of UWOC in dynamic channels. Recent sea trials are highlighted and summarized to provide references for the development of UWOC sea trial prototypes. We also propose a cost-effective implementation scheme for UWOC sea trials and report the first sea trial of a multi-hop UWOC system using this scheme. With future work in device innovation and optimization of sea trial implementation, practical UWOC systems are expected to be widely applied in ocean scientific research and ocean resource exploration.