Underwater source range and depth estimation using a vertical dual-hydrophone configuration in a deep sea bottom bounce areaa).

This paper addresses the challenge of pulse source localization in a deep sea bottom bounce area using multipath time differences via a vertical dual-hydrophone configuration. By analyzing the variation trends of multipath time-delay differences with respect to source range and depth in deep sea bottom bounce area, a set of analytical expressions relating multipath time-delay differences to source range and depth is derived based on geometric relationships. Furthermore, by integrating ray tracing technology with simulated annealing and Bayesian inversion methods, source localization within the range-depth two-dimensional plane is achieved. Simulation results indicate that the source positions calculated using the geometric analytical expressions can provide starting values for the other two methods. The Bayesian inversion approach demonstrates higher accuracy in estimating source range compared to simulated annealing. However, simulated annealing yields better depth estimation results with higher concentration. Sea trial results confirm the effectiveness of both methods in localizing cooperative sources under high signal-to-noise ratio conditions.