Underwater Positioning Algorithm Based on SINS/LBL Integrated System

The interactive assistance of a strap-down inertial navigation system (SINS) and a long baseline (LBL) underwater positioning algorithm based on time of arrival is studied, and this algorithm mainly includes a solution algorithm of equivalent sound velocity, 3-D LBL underwater positioning algorithm with aided of SINS. The proposed method can quickly get the ideal equivalent sound velocity to calculate the distance from sound source to hydrophones, and effectively reduce the positioning errors caused by the uneven distribution of underwater sound velocity and sound ray bending, with high flexibility and adaptability. The results of simulation indicate that compared with the traditional algorithm, the improved can correct the cumulative error more directly and effectively, and extend the working hours of autonomous underwater vehicles.