Method and implementation for calculating speed distributions with multi-pri and smprf radars

An arrangement for producing a computed distribution of speeds of scatterers in a target volume (1701), comprising:

• a distribution storage (1717) configured to store an estimate distribution of speeds at which scatterers would move in said target volume,
• an autocorrelation function calculator (1718) configured to convert estimate distributions to candidate autocorrelation functions, hereinafter candidate ACFs, that represent autocorrelation data points that a pulse radar would measure by remotely sensing said target volume (1701) if the distribution of speeds of scatterers within the target volume (1701) would equal a current estimate distribution,
• a measuring unit (1718) configured to measure the fit of a 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,
• a decision maker (1718) configured to make a decision that involves
• accepting the estimate distribution if a measured fit fulfils a predefined acceptance criterion, or
• modifying a current estimate distribution, and returning processing to the conversion of the modified estimate distribution to an ACF,
• and
• an output part configured to output an accepted estimate distribution as a computed distribution of speeds that describes said actual distribution of speeds.

A computer program product comprising machine-readable instructions that, when executed on a processor, make the processor to produce a computed distribution of speeds of scatterers in a target volume, through:

• a) providing (1201) an estimate distribution of speeds at which scatterers would move in said target volume,
• b) converting (1202) 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 (1203) 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 (1204) a decision that involves
• d1) accepting the estimate distribution if the fit measured at c) fulfils a predefined acceptance criterion, or
• d2) modifying (1205) the estimate distribution, and repeating steps b) to d) until the decision at step d) involves d1),
• and
• e) outputting (1206) the accepted estimate distribution as a computed distribution of speeds that describes said actual distribution of speeds.