DC signal magnitude in simulation (a), spherical phantom experiment (b), head experiment (c,e), and breath-held cardiac experiment (d,f). Measurement with a miscentered trajectory causes reduced signal level and large signal fluctuations (red traces). Trajectory estimation based on phase correction alone moderately increases signal level and reduces but does not eliminate signal fluctuations (blue traces). Trajectory estimation with the additional iterative application of GROG further increases signal level and reduces signal fluctuations (green traces).