Single sensor source localization in a range-dependent environment

Source localization with a single sensor explores the time spread of the received signal as it travels from the emitter to the receiver. In shallow water, and for ranges larger than a few times the water depth, the received signal typically exhibits a large number of closely spaced arrivals. However, not all the arrivals are equally important for estimating the source position since a number of them convey redundant information. Theoretically, identifying the non-redundant arrivals is feasible in a isovelocity range independent waveguide. In previous work, the number of nonredundant arrivals and the dimension of the data sample signal subspace have been related in a range-independent case. This paper addresses the problem of determining the number of significant arrivals for localizing a sound source over a range-dependent environment off the West coast of Portugal during the INTIMATE'96 sea trial.