Abstract: Marine information technology (MarineIT) involves marine information gathering, transmission, processing, and fusion. Traditionally, this topic has been referred to in the context of acoustic, optical, and electromagnetic sensing of the ocean environment, most notably sonar/radar processing and satellite remote sensing. As its embodiment becomes enriched and its scope extends, particularly accompanied by the advancements in cabled or wireless ocean observation networks, it is fair to refer to MarineIT as a dedicated discipline of information technologies. MarineIT plays an important role in many applications, such as marine science research, environmental exploration, resource exploitation, and security and defense. Owing to its specific application domain, it has also become a trending topic of the information technology research.
Like other branches of information science, the development of marine information technology over the last 30 years has benefited significantly from advances and achievements in general information theory. However, the manner in which it highlights the close bonding among propagation physics, signal processing, and the marine environment is seldom seen in other areas. As such, direct applications of general information methods to ocean environments do not usually work well, and MarineIT presents many features different from its terrestrial counterparts. For example, the ocean volume is seemingly transparent to sound, and thus acoustic waves are used as the main information carrier for underwater sensing and communications. Long-range sound propagation is subject to a so-called waveguide effect, spatially bounded by the sea surface and bottom, and temporally experiencing dramatic variation due to ocean dynamics. While the matched filter concept can still be applied, the signal replica used for matching is no longer a free field solution. Instead, a full-field solution has to be modeled, computed numerically, and even tracked for the given channel. In other words, propagation physical modeling and signal processing should match the ocean environment.
We have witnessed significant progress in MarineIT in recent years due to field-specific developments in signal and information processing, propagation physics modeling, and oceanographic data collection. The use of new observation platforms, such as underwater and surface vehicles, seafloor observatories, and wireless networks, offers important new opportunities. This special issue assembles eight peer-reviewed articles on underwater acoustic signal processing and communication, optical image processing, remote sensing, and application of unmanned underwater vehicles. This effort is intended to enlighten the research community about the recent progress in the field of MarineIT. It may also offer some insights into identifying important scientific issues to be addressed in the future.

海洋信息技术：最好的时代即将来临

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[10]Zhang RX, Ma XL, Wang DQ, et al., 2018. Underwater video transceiver designs based on channel state information and video content. Front Inform Technol Electron Eng, 19(8):984-998.