Research On Time Delay Estimation Method In Multi-source Ocean Acoustic Tomography

The problem of ocean acoustic tomography is to infer the state of the ocean traversed by the sound field from precise measurements of travel time, or of other properties of acoustic propagation. It is one important way to inverse sound velocity profiler by multi-path time delay estimation. The accurate delay information play a significant role in ocean acoustic tomography.To research ocean within limits,need to lay sound sources in different places. By received the sound signals from different directions, the information of time and multi-path are apply to gain the sound speed profile. According to the requirement of OAT,Multi-Source distinguished method and time delay estimation are researched in this paper. It is realized to distinguish the muti-source by using the m sequences.Based on ray theory, proposed a layered medium sound ray search, sound propagation time solving methods and simulation of sound propagation information in different ocean environment. MUSIC algorithm and correlation algorithm are applied to simulate the performance of time delay estimation in muti-source environment with m sequences sinal.Some sea experiment data are computed with the method given in this paper. The results show that, m sequence can effectively distinguish signal from different sound sources, and contribute to multi-path delay information extraction, the MUSIC algorithm is better than the replica correlation in high SNR.