Abstract: Disclosed is a method for the radar-based measurement of a filling level, in which method a difference curve is adjusted iteratively in successive measurement cycles to suppress interfering echoes. The iterative adjustment is accomplished by: calculating a difference curve from the evaluation curve and a predefined reference curve; determining the filling level from the evaluation curve within a selection region; checking if the difference curve satisfies a predefined criterion at at least one location; redefining the selection region at said location in the subsequent measurement cycle when the difference curve satisfies the criterion; and set the evaluation curve as a new reference curve when the difference curve satisfies the criterion. The iterative adjustment provides the advantage that the search region of the filling level maximum in the evaluation curve is limited on one side, and slowly changing interfering echoes can also be detected.