Using dolphin clicks to achieve high-speed bio-inspired covert underwater acoustic communication

Covert communication among underwater equipment is crucial for ensuring the secure transmission of information. A bio-inspired covert underwater acoustic communication scheme that uses biological signals as camouflage to evade detection is presented in this study. In contrast with the conventional methods, this approach employs broadband dolphin clicks as information carriers and embeds messages via click phase variations. This method not only supports high-speed communication but also maintains high biomimetic fidelity. Real-time image transmission experiments were conducted in shallow underwater acoustic channels with low signal-to-noise ratios. The results demonstrated that the communication performance of the proposed method could reach 10.209 kbps km, which is two orders of magnitude greater than the 0.72 kbps km achieved by the existing bio-inspired covert communication methods. Furthermore, this technique is flexible, enabling the use of various biological signals that are present in local ocean environments as signal carriers. It provides a viable solution for achieving high-speed covert communication between various underwater devices, such as buoys, divers, and unmanned underwater vehicles.