Title: The characteristic of sound propagation in deep water and underwater source localization in the direct zone

Author(s): WANG Mengyuan; LI Zhenglin; WU Shuanglin; QIN Jixing; YU Yanxin

Affiliation(s): State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences; University of Chinese Academy of Sciences

Abstract: The multiple-path sound propagation in deep water is conducive to source localization of an underwater target. The transmission losses (TLs) and broadband pulse multiple-path propagation characteristics from a deep receiver is analyzed by using the experimental data from deep water area in the South China Sea (SCS). The results indicate that the width of the direct zone near the bottom of 4300 m water depth is about 30 km. The TLs in the direct zone near the bottom are much less than those in the shadow zone. It is meaningful for underwater sound source detection. Moreover, the time delay between the direct path and the bottom-surface-reflected path for a receiver near the bottom decreases monotonically with the source range. According to the linear relationship between the time delay of multipath and source range, a source localization method is presented to estimate the range of underwater target. The experimental results show that the estimated ranges are consistent with the global position system (GPS) measurements, and the mean square error of the estimation results is less than 0.28 km.