Abstract: In order to localize the underwater sound source in deep sea,the arrival structure characteristics of active signals radiated by near-surface sources are analyzed.The approximate expressions of the amplitudes and the arrival times of cluster signals are given.Generally,the arrival signal at the receiver is in a cluster structure when the source and the receiver are near the sea surface.On the basis of extraction of the arrival time and the amplitude of each cluster signal,a method of localizing the underwater sound source by matching the characteristic parameters of cluster signals is proposed.The characteristics of cluster signals at different ranges and depths are analyzed by simulation.The effectiveness of the approach is preliminarily verified by using the experimental data achieved in the non-full deep sea area of the South China Sea.The results show that the characteristic parameters such as arrival time and amplitude corresponding to each cluster signal can be used to localize the underwater sound source.The range estimation results of underwater acoustic sources obtained by a single hydrophone are in good agreement with the measured results.The estimated errors for the range between 2.0 km and 90.4 km are less than 8%.