ELF Electric Field Detection of Surface Vessel Targets Using a Horizontal Electric Dipole Model

This study presents an ELF electric field detection method for underwater moving targets, modeling the hull corrosion current-induced field source as a Horizontal Electric Dipole (HED) within a three-layer marine electromagnetic framework. Theoretical analysis and shallow-sea experiments (48–56 m water depth) using self-developed broadband seabed-mounted electric field detectors validate the HED model's effectiveness, showing high consistency between measured and simulated electric field distributions. Experimental results highlight distinct harmonic features in ELF signals, enabling target detection via time-frequency analysis: the fundamental frequency reception window, combined with vessel speed, yields a maximum detection distance of 534 m. These findings confirm the feasibility of ELF -based electric field detection and the HED model's applicability in shallow-sea environments, offering essential technical support for the development of engineering-level detection systems.