Self-localization by eavesdropping in acoustic underwater sensor networks

Localization is a common problem in underwater sensor networks. Since global navigation satellite systems do not work underwater, geo-referencing of underwater sensors requires other technologies. In this paper, we present an novel localization approach for nodes in an acoustic underwater sensor network. By combining pressure sensors with the functionality of modern acoustic USBL modems, the nodes are able to self-localize their position inside the network. This can be done in a passive manner, just by listening to the transmitted messages of other network nodes, thereby saving energy and sparing the communication channel from additional traffic. In order to evaluate the performance of the method, experiments have been conducted in simulation and under real conditions in the Middle Atlantic Ocean.