Modeling technology of total field anomaly inversion by magnetic monopole array

Objectives The unmanned aerial vehicles are equipped with total field magnetic sensors to detect the total field anomaly above ships, and it is necessary to establish the corresponding total field anomaly inversion model to evaluate the underwater magnetic signature and airborne far-field magnetic signature of ships.

Methods A ship magnetic field inversion model based on the magnetic monopole array was established by the total field anomaly data measured in the plane above the ships. Based on the total field anomaly measured above the ship, the intensity of the ship’s magnetic monopole array can be obtained, so as to realize the evaluation and analysis of the ship’s three component magnetic field signatures above and below the ship. A validation test of steel ship model was carried out in the laboratory, and the magnetic fields of the ship model were measured from above and from below. By the total field anomaly in the measurement plane above the ship model, the inversion modeling was conducted.

Results The experimental results show that, the high-precision three component magnetic fields can be achieved on the magnetic field evaluation lines above and below the ship, by the total field anomaly inversion of three-dimensional magnetic monopole array distributing on the ship body.

Conclusions The proposed total field anomaly inversion modeling technique provides a certain theoretical and technical basis for the engineering application of unmanned aerial vehicle for measuring ship magnetic fields, and provides a viable alternative for ship magnetic field detection and analysis.