Gradient system characterization by impulse response measurements with a dynamic field camera

摘要: This work demonstrates a fast, sensitive method of characterizing the dynamic performance MR gradient systems. The accuracy time-courses is often compromised by field imperfections various causes, including eddy currents and mechanical oscillations. Characterizing these perturbations instrumental for corrections pre-emphasis or post hoc signal processing. Herein, chain treated as linear time-invariant system, whose impulse response function determined measuring responses to known inputs. Triangular inputs are used probe system measurements performed with camera consisting NMR probes. In experiments on whole-body it shown that proposed yields functions high temporal spectral resolution. Besides basic properties such bandwidth delay, also captures subtle features mechanically induced For validation, measured were predict evolutions, which was achieved an error below 0.2%. records spatial orders simultaneously, rendering suitable studying cross-responses shim It thus holds promise range applications, optimization, quality assurance, image reconstruction.