1. A method for producing a computed distribution of speeds of scatterers in a target volume, the method being run on a processor, comprising: a) providing an estimate distribution of speeds at which scatterers would move in said target volume, b) converting said estimate distribution to a candidate autocorrelation function, hereinafter candidate ACF, that represents autocorrelation data points that a pulse radar would measure by remotely sensing said target volume if the distribution of speeds of scatterers within the target volume would equal said estimate distribution, c) measuring the fit of said candidate ACF to a measured ACF that comprises data points that a pulse radar measured by remotely sensing an actual target volume where actual scatterers had an actual distribution of speeds, d) making a decision that involves d1) accepting the estimate distribution if the fit measured at c) fulfils a predefined acceptance criterion, or d2) modifying the estimate distribution, and repeating steps b) to d) until the decision at step d) involves d1), and e) outputting the accepted estimate distribution as a computed distribution of speeds that describes said actual distribution of speeds.