A New Decoupling Method for Quadrature Coils in Magnetic Resonance Imaging

Abstract

A powerful decoupling method is introduced to obtain decoupled signal voltages from quadrature coils in magnetic resonance imaging (MRI). The new method uses the knowledge of the position of the signal source in MRI, the active slice, to define a new mutual impedance which accurately quantifies the coupling voltages and enables them to be removed almost completely. Results show that by using the new decoupling method, the percentage errors in the decoupled voltages are of the order of 10(-7) % and isolations between two coils are more than 170 dB.

Mutual Coupling Compensation for Direction-of-Arrival Estimations Using the Receiving-Mutual-Impedance Method

“…In addition to theoretical studies, we have recently demonstrated experimentally that the RMIM can be used for mutual coupling compensation [28]. The RMIM has also been applied to mutual coupling compensation of DOA estimations using circular array [29] and phase array in Magnetic Resonance Imaging (MRI) [30][31][32]. Recently, the RMI has been adopted to model the mutual coupling effect of Multiple-Input Multiple-Output (MIMO) system and new models for channel capacities of the MIMO systems have been developed [33,34].…”

A Review on Mutual Coupling in Antenna Arrays and Decoupling Methods in MRI Antenna Arrays

“…Hence the position information of the active slice is available and can be used to define the receiving mutual impedance for MRI phased arrays in a very accurate manner. Studies using this method to decouple the array signals have been found in MRI surface coil arrays and MRI quadrature coils [23][24]. It was shown that mutual coupling could be almost totally removed and nearly coupling-free array signals can be obtained.…”

Mutual coupling compensation for direction finding using receiving mutual impedance

“…The receiving mutual impedance (RMI) has been used for decoupling in adaptive nulling [15] and direction finding [13] applications, resulted in better estimation accuracies comparing to the case when conventional mutual impedance is used for decoupling. The RMIM has also been applied to near-field imaging application such as magnetic resonance imaging [18].…”