Analysis and Experimental Verification of Low-Frequency Electromagnetic Scattering of Underwater Metal Targets Using the Method of Moments

Currently, electromagnetic scattering from various targets is widely utilized in high-frequency domains, particularly for aerial and terrestrial targets such as radar detection, nondestructive testing, communication, and remote sensing. However, the application of low-frequency electromagnetic scattering insubsurface and underwater environments remains relatively limited, despite its potential to detect unexploded ordnance, underwater objects, and buried seabed metals. Traditional methods for electromagnetic scattering computation often approximate the target as one or more dipoles and other auxiliary sources. While these methods offer a fast computational speed, they tend to introduce relatively large errors. To address this issue, this work employs the Method of Moments (MoM), a highly accurate numerical method, to model and simulate the low-frequency active electromagnetic scattering characteristics of underwater complex metal targets. We selected a typical large underwater unmanned vehicle (UUV) as the metal target for case analysis. The large UUV's comprehensive complex geometry is preserved through detailed CAD modeling and meshing. We simulated the scattering characteristics of the UUV under varying parameters using MoM and conducted the experimental verifications in an open lake environment. Comparisons between simulation and experimental results indicate a high degree of computational accuracy, validating the proposed approach for practical engineering applications.