An effective compensation method for the mutual coupling effect in phased arrays for magnetic resonance imaging

An effective compensation method to compensate for the mutual coupling effect in magnetic resonance imaging (MRI) phased arrays is introduced. This method uses the knowledge of the position of the signal source in MRI, i.e., the active slice, to define a new mutual impedance that accurately quantifies the coupled voltages and enables them to be removed from the terminal voltages almost completely. Numerical results using the method of moments show that the percentage errors in the compensated voltage are at least on the order of 10/sup -5/% and the isolations between two coils are more than 120 dB even at a low-field case of 0.5 T (f/sub 0/=21.3 MHz). This method can be implemented by either software or hardware.

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