Research on underwater sound velocity calculation, error correction and positioning algorithms

In this paper, the principle and algorithm of acoustic velocity calculation, sound velocity error correction and underwater acoustic positioning are presented. The acoustic velocity of sea water is calculated by the indirect methods, that is, the velocity of sound is calculated according to the depth, temperature and salinity. Acoustic velocity empirical models including Dell Grosso, Leroy, Mackenzie and other 6 models are introduced and compared. In this paper, we calculate the sound speed and make a numerical analysis based on the real-time observation data of China Argo buoy. A weighted average method for sound velocity error correction is used. An error calculation model for simulation data is proposed based on the principle of the sound velocity error amplification with the increase of propagation distance. The theory and algorithm of underwater positioning are introduced. The feasibility and stability of the under positioning software are verified by simulating data. The results showed that using the weighted average velocity correction, the sound velocity positioning accuracy can reach sub-decimeter level in x direction and decimeter level in the y and z directions.