Internet of Underwater Things Infrastructure: A Shared Underwater Acoustic Communication Layer Scheme for Real-World Underwater Acoustic Experiments

The advancement of underwater acoustic communication (UAC) holds great promise for the Internet of Underwater Things (IoUT). However, a critical challenge to the development of UAC technology is the difficulty of obtaining sea trial data, such difficulty makes the emerging algorithms inconvenient to evaluate. In this article, we propose a shared UAC layer (SUACL) to collect underwater acoustic signals, the proposed SUACL is founded on the IoUT, and users are allowed to remotely access the system to arrange underwater acoustic data transmission and reception via Internet. The SUACL system aims to enable the remote operation of communication units that are deployed in designated sea areas. The merit of the proposed SUACL is that the sea trial data can be obtained without risky and high expense, and the emerging underwater acoustic technologies can be evaluated in time. The SUACL is composed of the nonunderwater part, which includes the application layer and fusion layer, and the above/underwater part including the communication layer on which we focus. We provide a detailed description of the communication layer of the proposed SUACL system, such as the preamplifier with reconfigurable gain, the analog-to-digital converter with reconfigurable sampling rates, the reconfigurable transducers with different frequency bands, and the reconfigurable number of hydrophones. The SUACL's reconfigurability options make it a versatile tool that can meet the diverse experimental needs for underwater communication research. In addition, we also describe the mechanisms of how experimental data are exchanged through the SUACL. Our experimental results demonstrate the feasibility and effectiveness of the proposed SUACL in a shallow-water environment.