Design of a 7 T Spiral Resonator-Based Filter for MRI Planar Array Coupling Reduction

The design of a filter for the decoupling of a 7 T RF MRI planar array by using miniaturized spiral resonators is presented. First, we introduce the filter design guidelines and, then, we perform full-wave simulations on an arrangement of three adjacent MRI RF rectangular loops. The numerical results demonstrate that the proposed solution achieves excellent decoupling levels both between strictly adjacent and next-neighbors coils couples (better than -20 dB), while avoiding the use of additional lossy decoupling lumped elements connected into the coil array, hence accomplishing a mechanically robust and versatile design.