Research on high-precision detection technology for micro targets in shallow seabed of shallow sea

Due to small in size and shallow in burial depth, micro targets at shallow seabed are generally hard to detect precisely by available underwater acoustic detection methods. By applying seismic acoustic numerical simulation, we achieved high-precision detection of small targets at a shallow seabed by multi-channel seismic acoustic detection. First, the high-order staggered grid finite difference method based on wave theory was used to realize the forward modeling of small targets, to explore the seismic acoustic propagation response characteristics of shallow sea micro targets under different main frequencies, different seabed morphologies, and different burial conditions, and to summarize the propagation laws of small targets under different conditions. Furthermore, the reverse time migration technology with higher imaging accuracy was applied, from which high-precision imaging of the position and morphology of small targets was realized. The trial results of different shallow water micro targets models show that the multi-channel seismic acoustic detection method achieved high-precision detection of micro target objects at shallow water with accurate imaging positioning and good shape characterization.