Electronic method for suppressing output instability of GMI sensors caused by the orientation

Abstract

Magnetic sensors based on the giant magneto-impedance effect (GMI sensors) have a promising application prospect in the field of magnetic anomaly detection for their high resolution. However, they are highly sensitive to its orientation without any magnetic shielding. A method that automatically adjusts the bias magnetic field to make it always work on its initial value is proposed in order to suppress output instability of GMI sensors caused by the orientation. The analog circuit implementing the method is designed according to the principle of feedback control. The experimental results demonstrated the effectiveness of the proposed method.