Underwater Localization and Tracking of Physical Systems

In this paper, the authors investigate the problem of localizing an underwater sensor node based on message broadcasting from multiple surface nodes. With the time-of-arrival measurements from a DSP-based multicarrier modem, each sensor node localizes itself based on the travel time differences among multiple senders to the receiver. Using one-way message passing, such a solution can scale to accommodate a large number of nodes in a network. They consider the issue from not only the physical layer, but also at the node processing layer by incorporating a tracking solution. They present simulation results, testing results in a swimming pool featuring both stationary and moving receivers, and results from a lake test with a mobile receiver.