Fig. 3

Various forms of the navigator signal extracted from the magnitude of the k-space center before (blue) and after (red) filtering. The black dashed lines and the green dashed line indicate the detected cardiac and respiratory onsets, respectively. Also shown are the respiration windows within which all data are discarded and excluded from image reconstruction. Displayed is the navigator signal in (a) over three respiratory cycles, in (b) from different time points during the 2 h measurement (left to right) and in (c) with ADC delay and z-spoiling (top), with ADC delay and no z-spoiling (middle) and without ADC delay and no z-spoiling (bottom)