Decoupling capabilities of mushroom-type high-impedance metasurfaces in 7T MRI applications

Abstract

In this work we experimentally revise electromagnetic bandgap properties of high-impedance metasurfaces of the mushroom type and study their capabilities in decoupling elements of body-array coils for 7T MRI. We numerically optimize unit-cell parameters in order to improve isolation of densely packed dipole-type antennas operating at 298 MHz. We demonstrate by measurements, how the reachable isolation level depends on the distance to a phantom, the equivalent of human body tissues. The use of mushroom-type metasurface samples can potentially reduce SAR of prospective body-array coils due to reduction of inter-element coupling.