A Fast Electromagnetic Field and Radio Frequency Circuit Co-Simulation Approach for Strongly Coupled Coil Array in Magnetic Resonance Imaging

Electromagnetic (EM) coupling between radio frequency (RF) coils is a common cause of coil performance degradation and must be sufficiently reduced in the design of RF coils. The EM field simulation is a primary tool in analyzing the coupling condition and optimizing the decoupling method. A theoretical analysis of co-simulation under the conditions of strongly coupled RF coils is proposed in this paper. The proposed co-simulation method is evaluated through the comparison with the conventional simulation methods in terms of the efficiency and of the EM fields and specific absorption rate (SAR) of a two-channel strongly coupled coil array. The results demonstrate that the proposed co-simulation method saves approximately 94.5% of the total simulation time for strongly coupled coil arrays while the EM field and SAR variation is less than 4%. As a method demonstration, the proposed co-simulation method was used to analyze the capacitance decoupling of adjacent coils with the scattering matrix and saves about 95.78% of the total simulation time for the optimization of decoupling capacitors.