Patent ID: 7053615
Filing Date: 2006-05-30
Classification: G01R

Abstract:
1. A magnetic resonance system comprising: a basic field magnet that generates a homogenous, static basic magnetic field in an examination volume; a gradient system operable to superimpose at least one gradient magnetic field on said basic magnetic field in said examination volume; a primary RF transmitting antenna operable with an excitation current to generate an RF excitation field in said examination volume; a secondary RF transmitting antenna operable with an excitation current to generate an RF excitation field in said examination volume; an RF receiving antenna operable to receive magnetic resonance signals from said examination volume produced by magnetic resonance in an examination subject adapted to be disposed in said examination volume; a control element electrically connected to one of said primary and secondary RF transmitting antennas allowing setting of at least one of an amplitude ratio and a phase offset of the respective excitation currents in the primary and secondary transmitting antennas; and a control and evaluation unit connected to said gradient system, said primary and secondary RF transmitting antennas, and said RF receiving antenna, for operating said gradient system to generate said gradient magnetic fields and for operating said primary and secondary RF transmitting antennas, and said at least one control element, to generate the respective excitation currents in the primary and secondary RF transmitting antennas, and for evaluating the magnetic resonance signals received by said RF receiving antenna, said control and evaluation unit causing the excitation current in the secondary RF transmitting antenna to have a smaller amplitude than the excitation current in the primary RF transmitting antenna, for causing the RF excitation field generated by the secondary RF transmitting antenna to exhibit a smaller spatial extent than the RF excitation field generated by the primary RF transmitting antenna.