# High-Precision Aeromagnetic Compensation Method Under the Influence of the Geomagnetic Field

## TL;DR

This paper introduces a new method to improve aeromagnetic surveys by reducing interference from the Earth's magnetic field.

## Contribution

The novel GF-Based method uses Gaussian-process-regression to isolate geomagnetic influence and improve calibration accuracy.

## Key findings

- The GF-Based method effectively isolates geomagnetic interference during aeromagnetic compensation.
- Airborne experiments show the proposed method improves the improved ratio (IR) compared to existing methods.
- Gaussian-process-regression combined with measurement data enhances calibration fidelity.

## Abstract

Aeromagnetic surveys play an important role in geophysical exploration and many other fields. In many applications, magnetometers are installed aboard an aircraft to survey large areas. Due to its composition, an aircraft has its own magnetic field, which degrades the reliability of the measurements, and thus a technique (named aeromagnetic compensation) that reduces the effect of magnetic interference is required. Commonly, based on a figure-of-merit (FOM) flight, this issue is solved as a linear regression problem. However, the influence of the geomagnetic field, which refers to the magnetic interference introduced by the non-uniform magnetic field in the region, creates accuracy problems when estimating the model coefficients. The analysis in this study indicates that the geomagnetic field can be obtained by a data processing method based on Gaussian-process-regression (GPR) combined with the measurement process. Accordingly, we propose a high-precision compensation method, designated as the Geomagnetic Field-Based (GF-Based) method, which isolates geomagnetic influence to enhance calibration fidelity. This method restricts the impact of the geomagnetic field and improves the precision of the calibration. Compared with the existing methods which considered the geomagnetic field, the proposed method improves the improved ratio (IR), which is verified by a set of airborne experiments.