Ocean acoustic tomography based on travel time inversion relies upon the assumption that geometrical optics is appropriate and that acoustic rays can be resolved and identified. In the deep ocean, it has been shown that the acoustic arrivals are stable; however, acoustic transmission in shallow water, sound speed typically decreases with depth so that ray paths are refracted downwards and propagation to moderate ranges necessarily involving bottom bounces. Identifying the arrivals with particular ray paths becomes more difficult.
In order to overcome all above mentioned difficulty in shallow water, hydroacoustic transceiver have designed and developed to carry out test experiment on water area for measuring current speed and temperature with POI FEBRAS (Russia).
Localization is one of the most important issues associated with underwater acoustic sensor networks (UASNs), especially when sensor nodes are randomly deployed. In addition, all the information collected by sensor nodes may be useless unless the location of each sensor node is known. However, although various localization algorithms have been proposed for UASNs, it is still stating point of the research. In this project, we propose a new localization scheme and analyze the performance for UASNs considering various oceanographic data for improving localization accuracy.
