magnetic field control

The developed sensors enable the detection of magnetic field variation billions times smaller than the ambient field, which naturally may fluctuate by 0.1%. To detect variation million times weaker than the natural field fluctuations, special techniques are required to shield or stabilize the environmental field. 

We opted to face the challenging method of avoiding shieldingW and developed high-performance stabilization methodologies.

We built a setup to actively compensate for the common-mode magnetic disturbances on a multisensor device devoted to differential measurements. The system uses an FPGA card, and operates in conjunction with a high-sensitivity magnetometer: compensating the common mode of magnetic disturbances results in a relevant reduction of the difference-mode noise. The digital nature of the compensation system enables an automatically adjustment of the feedback-loop filter, which leads to a common-mode-disturbance attenuation exceeding 50 dB.