Abstract: Sound velocity profile (SVP) is an important parameter of multibeam sounding. However, in the complex area of water, sound velocity profile is often used to encrypt observations or interpolate observations, but there are always varying degrees of refraction errors. In order to enhance the quality of observation data, it is usually corrected by post-processing method. At present, the research tends to focus on acoustic tracking algorithm and how to enhance and invert SVP quality and methods. This paper analyzes the influence of sound velocity on sounding system and deduces how to build the constant gradient equivalent sound velocity model, and puts forward the constant gradient sound velocity profile correction model, which solves the influence of sound velocity substitution error or sound velocity profile inaccuracy well. The experimental results show that the model has better consistency in the topographic edge data of post-processing analytical data, and the quantitative results are better than the traditional sound velocity profile correction algorithm.

Key words: multi-beam sounding system, sound velocity profile correction, multi-layer constant gradient sound velocity profile model, acoustic tracking