Patent ID: 8843329

Claim:
A computer-implemented echo transit time based method of measuring a filling level of a fill material in a container, comprising the following steps executed by a processor: generating an echo curve; and analyzing the echo curve using at least one analysis method selected from the group of analysis methods comprising (a) analyzing the echo curve using at least two parallel tasks executed in parallel; wherein at least one of the two parallel tasks includes an evaluation task; wherein at least one of the two parallel tasks includes a measurement task; wherein the evaluation task includes determining, from a plurality of received reflections as recorded by the echo curve, an approximate echo position of the fill material surface; wherein the measurement task includes refining said approximate echo position by determining a distance between the echo position and a reference echo; and (b) analyzing the echo curve by subtracting from a determined carrier-frequency amplitude-modulated echo profile a carrier-frequency amplitude-modulated spurious profile that does not represent a filling level, the spurious profile being previously determined while no fill material is present in the container.