A compact electromagnetic bandgap structure based on multi-layer technology for 7-Tesla magnetic resonance imaging applications

A compact electromagnetic bandgap (EBG) structure based on multi-layer technology for 7-Tesla magnetic resonance imaging (MRI) applications is presented. The proposed structure introduces an additional floating metallic layer between the top surface and the ground plane of the conventional single-layer uni-planar EBG structures, which provides more capacitive coupling between the adjacent unit cells. Thus, for the desired operating frequency (300 MHz), a miniaturized dimension of the unit cell, about 2.6% of the free-space wavelength, is achieved. The proposed structure is characterized by the reflection phase and the stop-band properties. The full-wave simulations and experimental results show a good agreement.