Research into range errors in hydroacoustic positioning systems

Ranging algorithm is one of the key technologies of hydroacoustic positioning technology in ocean mapping, in which time delay estimation and sound speed are the key factors to determine the ranging accuracy. In this paper, a hydroacoustic signal ranging processing method is designed for the influence of time delay estimation and sound speed error on ranging accuracy. The method integrates orthogonal demodulation algorithm, carrier synchronization algorithm and matched filtering and other algorithms. The simulation results show that under the conditions of different signal-to-noise ratios, the mean absolute value of the experimental ranging error is 0.328m, which exhibits good ranging accuracy and stability, and maintains a good ranging performance. Through the tests at different distances in the pool, the average ranging error of each group of tests is no more than 0.5m, which verifies that the ranging accuracy of the algorithm can reach the decimeter level and can effectively improve the positioning accuracy of the hydroacoustic system. The study shows that, although the time delay estimation method and the sound speed parameter have certain errors, the algorithm can still maintain a more ideal accuracy for the system ranging, help the hydroacoustic positioning system to carry out ranging, and effectively support the oceanographic mapping and geographic information applications in related fields.