Abstract: A method of measuring the flow rate of a fluid includes a first ultrasonic signal being transmitted and received with the flow and a second ultrasonic signal being transmitted and received against the flow on a measurement path obliquely to a direction of flow of the fluid. A first time of flight of the first ultrasonic signal and a second time of flight of the second ultrasonic signal are determined and the flow rate is determined from a time of flight difference. The ultrasonic signals have a plurality of periods of a carrier frequency having an amplitude modulated in accordance with an envelope and a respective reception point in time of an ultrasonic signal is fixed from a selected oscillation of the ultrasonic signal that is selected with reference to the progression of the envelope for the determination of the times of flight.

Abstract: A method for controlling a filling process, wherein a predetermined filling quantity of a medium is filled into a container, the flow rate of the medium flowing into the container is measured as a time series of measured values for the instantaneous flow rate and a filling quantity already filled is estimated from the time series, wherein at least one current measured value of the time series is corrected on the basis of at least one earlier measured value of an earlier time series of measured values of the flow rate of an earlier filling process.

Abstract: A method for controlling a filling process, wherein a predetermined filling quantity of a medium is filled into a container, the flow rate of the medium flowing into the container is measured as a time series of measured values for the instantaneous flow rate and a filling quantity already filled is estimated from the time series, wherein at least one current measured value of the time series is corrected on the basis of at least one earlier measured value of an earlier time series of measured values of the flow rate of an earlier filling process.