Michal Janosek | Searcharxiv

arXiv2019

Precise calibration method for triaxial magnetometers not requiring Earth's field compensation

A calibration procedure for calibrations of triaxial magnetometers is presented. The procedure uses a triaxial Helmholtz coil system and an Overhauser scalar magnetometer and is performed in the Earth's field range. The triaxial coils are first calibrated with the Overhauser magnetometer, and subsequently, a triaxial magnetometer calibration is performed. As opposed to other calibration approaches, neither Earth's field nulling system nor movements of the magnetometer are needed. A real calibration test was carried out-the extended calibration uncertainty was better than 430 ppm in sensitivity and 0.06° in orthogonality.

physics.ins-det↗

arXiv2019

Magnetic Calibration System With Interference Compensation

This paper describes a novel method for calibrating dc-precise magnetometers in the low field range (100 uT), which gives acceptable results even in laboratory conditions with significant magnetic interference. By introducing a closely mounted reference magnetometer and a specific calibration procedure, it is possible to compensate for the external magnetic field disturbances caused, e.g., by the local transportation operated with dc power supplies. The field compensation occurs only shortly after the calibrating coils are energized. In this case, the leakage of the coil's magnetic flux to the reference sensor due to the cancellation of the time-varying compensating field was negligible. When using 60 cm coils and reference sensor in 2.5 m distance, we were able to calculate magnetometer gains with a standard deviation of 91 ppm. We show that an overall uncertainty of 0.1% can be achieved.

physics.ins-det↗