Method for determining the fill level and fill level meter

摘要

A method for determining the fill level of a process medium arranged in a container using a TDR fill level meter having at least one signal line for guiding an electromagnetic signal, a signal line head and an electronics unit, the signal line extending into the process medium, the method having at least the steps of generating a pulsed transmitter signal with the electronics unit, wherein the transmission signal propagates along the signal line as measuring signal with changing amplitude, detecting and evaluating at least one reflection signal with the electronics unit, wherein the reflection signal is a reflection of the measuring signal on an interface between a first and a second medium having different impedances, the relative permittivity of the second medium is determined at least in dependence on the amplitude of the measuring signal transmitted through the first medium and the amplitude of the reflection signal.