Magnetic Sensor Calibration Based on Multi-frequency Signal

Magnetic sensor is widely used in electromagnetic field to get the real weak magnetic field intensity. Because the sensor outputs voltage and the parameter applied in electromagnetic in fact is magnetic field intensity, it should to be known precisely relationship between output voltage of the sensor and the magnetic field, that is to say, the sensor should be calibrated before applied in electromagnetic. When the sensor was calibrated in the past, the exciting signal origin from calibration system was usually sine wave or square wave. In this paper, we bring up a kind of calibration method that the exciting signal is multi-frequency signal. There are some advantages by using the method: First, the exciting signal can be produced easily. Second, the frequency of the exciting signal can be set low as far as possible. Thirdly, the calibration efficiency is improved significantly without effecting calibration precision because of all useful frequency point energy occupying most of total energy of the exciting signal. The result of experiment proves that this calibration method is feasible and high efficiency.