The objective of this research is to address one of the greatest challenges that hinder the development of underwater sensor networks into practical systems: How to ensure data reliability and delivery efficiency over unreliable acoustic links with large error rates, low available bandwidth, and long propagation delays. The project proposes an integrated coding approach, seamlessly combining digital fountain, and network and channel coding schemes with complementary strengths, across the application, network, and physical layers.
The intellectual merit of this project lies in the rigorous study of the underwater network limits and a systematic design of powerful fountain and network coding schemes to address the challenging issues facing underwater sensor networks. The project outcomes will include physical layer network coding theoretical results, novel non-binary fountain codes, sparse linear network codes, and physical-layer network coding schemes for underwater channels, as well as networking protocols for underwater unicast scenarios. The theoretical results, coding, and protocol designs will be evaluated through real world experiments.
The broader impact of this project is reflected in two aspects. First, this project is expected to accelerate the development of emerging underwater sensor networks, which will have major impact on scientific communities, national security, and the society as a whole. Second, this project will expose graduate students to new challenging research problems, fostering them to become leading experts in the fast-growing field of underwater acoustic networks. It will also support undergraduates, women and other under-represented groups, allowing them to participate in advanced research and its practical applications.
Underwater channels have long propagation delays, and fast variation. Such characteristics pose great challenges for communication modem design. The objective of this research is to address one of the greatest challenges that hinder the development of underwater sensor networks into practical systems: How to ensure data reliability and delivery efficiency over unreliable acoustic links with large error rates, low available bandwidth, and long propagation delays. The project has studied some fundamental theoretical limits in wireless and underwater networking systems. The effect of interference is quantified through various theoretical tools. These results are fundamental in nature and they will be important for designing network systems where interference is the main performance limiting factor. The research also provided a novel physical layer perspective on uncoordinated and non-exclusive random access in an underwater network. The derived expresssions for the interference distribution, outage probabilities, and ergodic capacities provide useful guidelines on the design of underwater network transmissions, and theoretical performance limits. This project is expected to accelerate the development of emerging underwater sensor networks, which will have major impact on scientific communities, national security, and the society as a whole. This project has also exposed graduate students to new challenging research problems, fostering them to become leading experts in the fast-growing field of underwater acoustic networks. It has also supported undergraduates, including women students allowing them to participate in advanced research and its practical applications.
