Ashraf ABUELHAIJA, Sana SALAMH, Osama NASHWAN

Decoupling network for Tx/Rx body coil for 7T MRI

The parallel imaging technique is widely used in 7T MRI scanners. It employs multichannel RF coil arraysto apply a concurrent excitation and acquisition method. Concurrent excitation faces significant challenges in terms ofelectromagnetic coupling between the RF coil elements. In order to prevent interference between the RF coil elements’exciters, several decoupling methods have been developed to compensate for coupling and to permit independent workfor the exciters. This paper studies the coupling between meander coils arranged in two different geometrical setups andinvestigates the isolation performance between the coils by applying two different decoupling networks depending on thegeometrical setup of the coils. These two decoupling networks in addition to a T-shaped decoupling network have beenintegrated into a Tx/Rx body coil for 7 T to compensate for mutual coupling between array coil elements. The resultshave been obtained by using CST Microwave Studio (CST AG, Darmstadt, Germany).

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