Method for measuring a filling level

A method for radar-based measurement of a filling level of a filling material in a container, the method comprising the following steps, which are repeated in successive measuring cycles:

• emitting a microwave signal in a direction of the filling material;
• receiving a receive signal generated after reflection of the microwave signal inside the container;
• generating an evaluation curve based on at least the receive signal;
• progressively storing the current evaluation curve in each measuring cycle;
• calculating a first difference curve based on the evaluation curve of a current measuring cycle and a stored evaluation curve of a preceding measuring cycle;
• and
• determining the filling level based on a maximum of the current, first difference curve.

A radar-based filling-level measurement device for determining a filling level of a filling material in a container, the device comprising:

• a signal-generation unit configured to emit a microwave signal in a direction of the filling material in each case in successive measuring cycles;
• a receiving unit configured to receive a corresponding receive signal generated after reflection of the microwave signal inside the container;
• an evaluation unit configured to:
• generate an evaluation curve in each measuring cycle based on at least the receive signal;
• progressively store the respective current evaluation curve;
• calculate a first difference curve by subtracting the evaluation curve of the current measuring cycle and the evaluation curve of a preceding measuring cycle;
• and
• determine the filling level based on the first difference curve.