A fast and simple algorithm for designing time-optimal waveforms is presented. The algorithm accepts a given arbitrary multi-dimensional k-space trajectory as the input and outputs the time-optimal gradient waveform that traverses k-space along that path in minimum time. The algorithm is non-iterative, and its run time is independent of the complexity of the curve, i.e. the number of switches between slew-rate limited acceleration, slew-rate limited deceleration and gradient amplitude limited regions. The key in the method is that the gradient amplitude is designed as a function of arc length along the k-space trajectory, rather than as a function of time. Several trajectory design examples are presented.
Michael Lustig, Seung-Jean Kim, John M. Pauly