Investigation of the resonance behavior of a MR-birdcage applying a 3-D-FEM code

For NIR-imaging processes, high precision in the homogeneity of the static magnetic field (B) over right arrow (0) and of the high frequency transvers al field (B) over right arrow (1) is extremely important. Investigations on the behavior of the field (B) over right arrow (1). in a widely used birdc age resonator type consisting of twelve rods are presented in this paper. O n coil systems for (B) over right arrow (0)-fields of 1.5 T and of 4.0 T th e field requirements at resonance will be discussed. Special attention is p aid to the influence of necessary RF-shields. The numerical simulations of the resonators are done using a 3D finite element code, based on an edge el ement formulation.