Chirp pulse xy.m
Chirp pulse waveform with a sine bell or quarter sine amplitude envelope in Cartesian coordinates.
The pulse is normalised to achieve an inversion across the band. It can be used either as conventional unidirectional chirp pulse, (wurst or smoothed) or smoothed saltire which is superposition of two counter sweeping chirps, as used in PSYCHE decoupling.
npoints - number of discretization points in the waveform duration - pulse duration, seconds bandwidth - chirp sweep bandwidth around zero frequency, Hz smfactor - smoothing parameter, a real positive number for sine bell smoothing (wurst): normally 1 - 80 for quarter sine smoothing (smoothed and saltire), in percent: should be in the range 0 - 50 chirptype - 'wurst', 'smoothed', or 'saltire'
Cx - real part of the waveform, rad/s Cy - imaginary part of the waveform, rad/s (zeros for saltire pulse)
See shaped_pulse_5.m in examples/nmr_liquids for a common usage case.
Note that pulse amplitudes are given in rad/s. This matches the syntax requirements of shaped_pulse_xy.m function.