An investigation of alternating impedance microstrip transceiver coil arrays for MRI at 7T

The magnetic field generated from the conventional microstrip resonator (MSR) is inhomogeneous along the resonator axis. It is strong at the centre and weak at the terminating ends. To homogenize the B₁⁺ field, it is required to modify the traditional MSR. Recently, an approach based on alternating impedance MSR has been presented. From this contribution, another configuration of alternating impedance resonator with circular elements is proposed. Electromagnetic (EM) simulations were performed for three types of MSR volume coils (one traditional and two alternating impedance) for MRI at 7T. Results indicate that, the alternating impedance MSR with circular elements is the best coil in terms of the B₁⁺ field homogeneity and the E/B₁⁺ field ratio reduction at 7T.