Real-Time Localization of Magnetic Target Using Second-Order Scalar Magnetic Gradients

Area of Science:

• Geophysics
• Applied Magnetism
• Signal Processing

Background:

• Magnetic anomaly detection is crucial for various applications.
• Accurate real-time localization of magnetic targets remains a challenge, especially for mobile systems.
• Existing methods often rely on iterative optimization, limiting real-time applicability.

Purpose of the Study:

• To propose a novel real-time magnetic target localization method.
• To leverage second-order scalar magnetic gradients at the closest point of approach (CPA) for enhanced accuracy.
• To develop a method that avoids computationally intensive iterative global optimization.

Main Methods:

• Exploiting the geometric symmetry of magnetic anomaly fields at the CPA.
• Deriving closed-form expressions for target position and magnetic moment from second-order spatial derivatives.
• Constructing a residual-based error index for automatic CPA determination during platform motion.

Main Results:

• The proposed error index accurately identifies the CPA point on the trajectory.
• Localization accuracy is significantly improved near the CPA.
• Experimental validation shows low relative errors for estimated distances (0.89%, 1.0%), angles (0.38%, 0.52%), and magnetic moment magnitude (4.85%).

Conclusions:

• The developed method enables real-time, accurate magnetic target localization.
• The approach offers significant advantages over iterative methods, particularly for mobile systems.
• This technique holds substantial value for enhancing the capabilities of mobile magnetic anomaly detection systems.