Hybrid Control Method Based on Dual-Coil for Improving Uniformity and Stability of Magnetic Field for MEG Measurement

The magnetoencephalography (MEG) measurement is important for diagnosing and treating brain functional diseases. MEG measurement based on the atomic magnetometer requires highly uniform and stable magnetic field environment, which is usually achieved by combining magnetic shielding room (MSR) and biplanar coils control system. However, the control effect heavily relies on the performance of the MSR. A hybrid control method based on dual-coil is proposed in this study, which reduces the dependence of the control effect on the MSR by actively adjusting the magnetic field distribution in the MSR and ensures high control accuracy based on the Rayleigh model relationship between the compensation coils and the MSR, better results can be achieved compared with the biplanar coils control system. The proposed method can provide certain reference for developing the active and passive combined magnetic shielding system with low cost and high performance for the MEG.