Key technologies of parametric array sub-bottom profiling and the application for real data

In recent years, parametric array sub-bottom profiling has been increasingly applied in the field of seabed shallow sub-bottom detection for the convenience and high-resolution imaging capability at shallow sub-bottom. However, during data acquisition, it is influenced by the acquisition environment and instruments, resulting in blurred reflection phase axes and unbalanced energy in the data. Although techniques such as Hilbert transform and energy balancing are commonly used to improve data resolution, the results are not always satisfactory. Based on conventional technology, we introduced a main frequency band zero-phase filtering correction method and an amplitude gain control method based on the Hilbert transform, which further resolved the issues of phase axis blurring and energy imbalance in parametric array sub-bottom profile with higher data resolution. The resultant profile exhibited a high signal-to-noise ratio, continuous and clear phase axes, balanced energy between traces, and distinct wave group characteristics, thereby providing a data support for the detection of seabed topography and shallow subsurface geological structure in the survey area.