CAREER: Transforming Underwater Networking with Acoustic Reconfigurable Intelligent Surfaces

Underwater communication is much harder than over-the-air communication. Radio waves do not travel well in water. Underwater systems usually rely on acoustic communication, which uses sound to carry information. However, sound travels much more slowly and can transmit far less information than radio waves, making it difficult for underwater robots, sensors, and vehicles to communicate effectively and reliably. This project studies a new technique called underwater acoustic reconfigurable intelligent surfaces (UA-RIS). These are special panels that can control how sound waves reflect in water, helping signals travel farther and improving the amount of information they can carry. The goal is to build the scientific foundation for smart underwater communication and sensing systems that could support ocean research, environmental monitoring, offshore infrastructure inspection, and maritime security. The project also benefits society by training students, creating open tools and datasets for researchers, and engaging the public through education and outreach activities that encourage interest in ocean technology and engineering. This project aims to develop the theoretical, algorithmic, and experimental foundation of UA-RIS-assisted underwater networks through three tightly integrated research thrusts. First, it designs and models innovative UA-RIS architectures using coupled electromechanical and acoustic methods, including reflector analysis, propagation modeling, and communication-capacity evaluation, together with optimization of reflector structures, quantization levels, and spatial control codebooks. Second, it establishes a localization framework that includes new passive localization methods, modeling of effects of hardware timing jitter on angle estimation errors, bounds on localization accuracy, and integrated passive-active co-localization algorithms. Third, it extends UA-RIS from link-level performance improvement to network-level operation through multi-user optimization, UA-RIS-aware medium access control (MAC) design, and an open-access calibrated simulator. The outcomes include new UA-RIS theory, novel underwater localization methods, analytical bounds on localization errors, optimized architectures and networking protocols, passive-localization hardware and algorithms, and open tools for the underwater networking research community. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2544545 | Program: 01002930DB NSF RESEARCH & RELATED ACTIVIT,01003031DB NSF RESEARCH & RELATED ACTIVIT,01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Lina Pu | Institution: University of Alabama Tuscaloosa, TUSCALOOSA, AL | Award Amount: $357,859 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2544545 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2544545.html