A method of controlling a radar system by: receiving a radar return signal from a target and generating a range-Doppler target image signature of the target; selecting a spectral line within the range-Doppler target image signature from a modulation feature on the target which includes an effective point scatterer; providing a range profile for the spectral line; obtaining a reference range profile of a reference point scatterer; and determining a difference between a power at a range shorter than a peak corresponding to the modulation feature in the range profile and a power at a corresponding range of the reference range profile. The method may further include controlling provision of the range-Doppler target image signature based on the difference.