Abstract:

An improved bathymetry method based on sector-divided deconvolution and target echo interval determination is proposed to address the issue of V-shaped deep-water multibeam echo sounder (MBES) receiving beam width being wider than that of T-shaped sonar with the same scale, leading to poor bathymetry effect in the mirror echo region of seabed. This method improves the bathymetry accuracy and resolution of the mirror echo region of the seabed by processing the conventional beamforming (CBF) output through the sector-divided deconvolution algorithm, resulting in a reduction of the receiving beam-width and sidelobe level. Additionally, the high computing load caused by the sector-divided deconvolution algorithm is decreased by using the multi-detection algorithm to determine the target echo interval of the transmitted sector based on the CBF output. The simulation results demonstrate that, in comparison to conventional bathymetry methods, the proposed method enhances bathymetry resolution and yields more distinct shapes and images of submarine targets. On the other hand, in various scenarios of seabed terrain, the accuracy of bathymetry is enhanced, with on improvement of exceeding 70% when compared to conventional bathymetry methods. The calculation efficiency is significantly increased by using multiple detection algorithms to determine the target echo interval beforehand. In various scenarios involving seabed terrain, the calculation time increase rate exceeds 96%, making the method convenient for subsequent real-time application. The sea test data also demonstrates the viability of the proposed method in real-world engineering applications, and it improves sounding accuracy over the conventional bathymetry method by 37.66%.

Key words: multibeam echo sounder (MBES), V-shaped installation, bathymetry method, sector-divided deconvolution, target echo interval determination