3D Acoustic Model for Geometrically Constrained Environments

The goal of this work is to demonstrate and validate a 3D acoustic propagation model for use in constrained environments such as harbors. The 3D model will be used to model system performance for 1) passive sonar, 2) active sonar, and 3) acoustic communications networks. This latter application is of primary importance in this Phase II Extended proposal. To accomplish these goals are sequence of field tests has been proposed in diverse sites including harbors and estuaries. In these field tests a variety of measurements will be made. The environment, especially bathymetry will be measured using specialized autonomous systems called Jetyaks. The ocean propagation conditions will also be measured using the Jetyaks as receivers to record the echo pattern in the channel due to a towed source. Finally, the Woods Hole acoustic communications group will measure modem performance in these same conditions. By analyzing all this data we hope to demonstrate a reliable predictive capability for modem performance in such constrained environments. This in turn will enable modem networks to be optimized for other constrained environments in terms of network geometry as well as modem parameters such as data rate and modulation scheme.