High-Speed Bio-Inspired Covert Underwater Acoustic Communication Technology for Underwater Internet of Things

The secure transmission of sensitive data within the underwater internet of things (UIoT) is crucial. Bio-inspired covert underwater acoustic communication (BCUAC) employs marine biological acoustic signals as camouflaged carriers for data transmission, enabling adversaries to mistake communication signals for biological sounds, thereby achieving covert communication. However, existing BCUAC methods suffer from very low transmission rates, rendering them unsuitable for the high data capacity demands of the UIoT. In this paper, we propose a high-speed BCUAC method based on dolphin clicks and phase rotation modulation (ClickPRM), which transmits information via phase variations of the clicks. Both theoretical analysis and experimental validation confirm the method’s camouflaging effectiveness. Utilizing ClickPRM, we achieved real-time image transmission between two UIoT nodes in shallow water, with a communication distance of 405 meters and a rate of 11.22 kbps, demonstrating communication performance an order of magnitude higher than that of existing BCUAC methods. Furthermore, this technology offers flexible camouflage carrier switching, providing a viable solution for secure data transmission across various UIoT scenarios.