Autocalibration of Field Monitoring Arrays by Reference Tones

David Otto Brunner¹, Christoph Barmet¹, Maximilian Haeberlin¹, Bertram Jacob Wilm¹, Klaas Paul Pruessmann¹

Monitoring of gradient waveforms significantly enhances the quality of reconstructed MR images especially in case of fast read-out schemes. For this the geometrical positions of the sensors have to be calibrated, which is typically done in a dedicated preparation. This becomes unmanageable if the probe positions are changing during scanning. Here we propose a novel approach that uses small signal tones on the gradients occupying portions of the FM spectrum that are otherwise unused in order to autocalibrate the monitoring setup during acquisition. These tones have marginal influence on the trajectory and no impact on the sequence.