Pedram Yazdanbakhsh1, Andreas Bitz2, Stephan Orzada2, Oliver Kraff2, Mark E. Ladd2, Klaus Solbach1
1High Frequency Technique, University Duisburg-Essen, Duisburg, NRW, Germany; 2Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen, Germany
Butler Matrix is used to drive the individual rungs of the DBC (Degenerate Birdcage Coil) in linear combinations to form the uniform birdcage mode as well as higher gradient modes. The advantage of using the modes of a birdcage coil excited by a Butler Matrix is that they form naturally decoupled orthogonal modes that do not require decoupling strategies. The Butler Matrix can also provide reflection coefficients that are insensitive to the load. In this work a novel reduced-size 8×8 high-power Butler Matrix has been designed and fabricated at 300 MHz to excite a coil array in 7T MRI.