(EN) The invention relates to a method of measuring the flow in a dielectric pipe (18) and to a flow meter. Two microwave signals at different frequencies and modulated and/or polarized in different ways are transmitted at measurement points via at least two transmitter antennae (12 to 13) through the dielectric pipe (18) and a flowing material (19). The distance between the measurement points is known. The signals (20 to 21) that have passed through are received by receiver antennae (14 to 15) and signal cross correlation is formed by a correlator (17), the flow rate being determined on the basis of the best correlation result. The measurement result is improved by filtering and/or directing the signals (20 to 21).