Interconnecting L/C components for decoupling and its application to low-field open MRI array

Abstract

Interconnecting L/C components are often applied to decouple the array elements for parallel imaging. Although it has been recognized that interconnecting capacitors and inductors can both be employed for decoupling, quantitative study of this decoupling technique has not yet been presented. In this study, a theoretical analysis for the interconnecting L/C decoupling circuit is provided. The analysis reveals that the required decoupling capacitance decreases with the resonant frequency, whereas the decoupling inductance is independent of the frequency. The inductive decoupling scheme is applied in the design of a four-channel knee coil for 0.5 T open MRI with vertical magnetic field. Experimental results show that good isolations (−19 dB ∼ −45 dB) between coil elements can be achieved and only 5% ∼ 11% degeneration of Q is caused by this decoupling method.