Patent ID: 7426443

Claim:
A device for determining and/or monitoring volume flow and/or mass flow of a medium flowing through a pipeline in a stream direction comprising: at least two ultrasonic transducers, which emit ultrasonic measuring signals into the pipeline and receive ultrasonic measuring signals from the pipeline; and a control/evaluation unit, which ascertains the volume-flow and/or mass-flow of the medium in the pipeline on the basis of the travel-time difference of the ultrasonic measuring signals in the stream direction (S; Up) and counter to the stream direction, wherein: said control/evaluation unit ascertains a plurality of sampled values (a i with i=1, 2, 3, . . . ) of a received measuring signal at defined points in time (t) of a predetermined time range, interpolates the predetermined time range of the measuring signal by a continuous function (f(t)), the continuous function (f(t)) being formed by a sum of a predetermined number (n ∈ N) of wavelets (W), wherein each wavelet (W) corresponds to the product of a sampled value with a sine function ( sin ⁡ ( x ) x ) and with a Gaussian bell curve (e −αx 2 ,α ∈ R).