Critical Design and Characterization Methodology for a Homemade Three-Axis Fluxgate Magnetometer Measuring Ultra-Low...

Area of Science:

• Geophysics and Space Physics
• Instrumentation and Measurement

Background:

• Accurate measurement of ultra-low magnetic fields is essential for diverse scientific and technological applications.
• Existing magnetometers may face limitations in sensitivity, stability, or cost for specific ultra-low field applications.

Purpose of the Study:

• To design, fabricate, and characterize a homemade tri-axial fluxgate magnetometer for ultra-low magnetic field measurements.
• To achieve high sensitivity and stability in the developed magnetometer.
• To provide a detailed understanding of the sensor's performance and calibration.

Main Methods:

• Detailed design and fabrication process, including material selection and sensor geometry optimization.
• Comprehensive characterization including zero-field voltage, scale factor, resolution, noise, bias, cross-field effects, temperature dependency, and bandwidth.
• Development of a matrix-form model function to relate output voltage to magnetic field, accounting for temperature and cross-field effects.

Main Results:

• Achieved a minimum detectable magnetic field resolution of 2.2 nT.
• Demonstrated a noise level of 1.1 nT/√Hz at 1 Hz.
• Minimized temperature dependency impact through calibration to less than 5 nT over a 60 °C range.

Conclusions:

• The developed tri-axial fluxgate magnetometer offers high sensitivity and stability for ultra-low magnetic field measurements.
• Meticulous calibration and optimization are critical for achieving reliable performance in fluxgate magnetometers.
• The sensor is suitable for various applications, including space exploration and biomedical diagnostics.