Abstract:The magnetoimpedance effect has the evenorder nonlinearity. To solve this problem, a selfbalanced detection method is proposed. By applying AC bias field and using phase sensitive detection, the output of sensor has the feature of odd symmetry. The direction of external field can be detected without DC bias. Then, a proportionalintegral (PI) controller is utilized to form a closedloop detection system. When the system reaches the steady state, the feedback field and the external field are counteracted with each other. And the selfbalanced detection will be implemented. In this way, the nonlinearity of the sensor is eliminated. Experiments are implemented on a thinfilminductive magnetic sensor. Results show that the output of the selfbalanced detection method has good linearity, and the nonlinearity is only 082%. The measurement range is enlarged double. Even under different AC bias, the output characteristics is consistent and the correlation coefficients are all larger than 0999 9. The selfbalanced detection with AC bias is suitable for all nonlinear magnetic sensors. Different kinds of nonlinear characteristic can be eliminated by the proposed method and the highlinear output can be achieved.