Sound Ray Correction Method for Deep-sea Target Localization in Asynchronous Underwater Acoustic Sensor Networks

The target localization of underwater acoustic sensor networks is mainly based on the geometric principle. The uneven underwater sound speed leads to the bending of sound ray propagation. U sing constant sound speed to calculate the distance between the node and the target will produce a large error. At the same time, the complex and variable underwater environment makes it difficult to achieve strict clock synchronization between the underwater nodes and the target. In this paper, a sound ray correction method for deep-sea target localization is proposed for the case of clock asynchronization between nodes and target and sound ray bending. The method can obtain the accurate horizontal distance between the node and the target when the grazing angle of the node is known, and then improve the target localization accuracy. The sound ray correction method is verified by BELLHOP model and MATLAB simulation. Firstly, the correction effect of the traditional sound ray correction method is simulated when there is an error in the propagation time, and the results show that the traditional sound ray correction method is no longer applicable to the situation of clock asynchronization between node and target. Finally, the sound ray correction method proposed in this paper is simulated, and the results show that the method can significantly improve the accuracy of the target localization.