Patent ID: 11906335
Assignee: ENDRESS+HAUSER FLOWTEC AG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 31:
32. The method of claim 15, wherein the method is performed using a measuring system adapted to perform the method, the measuring system comprising:
a tube arrangement comprising a lumen defining the first portion of the flow path, the second portion of the flow path disposed in a flow direction downstream of the first portion, and the third portion of the flow path disposed in the flow direction downstream of the second portion and a tube wall surrounding the lumen;
the flow obstruction arranged within the tube arrangement in the second portion of the flow path, the flow obstruction configured to effect a disturbance in the flowing fluid, the disturbance dependent on the at least one measurement variable and/or serving as a measurable effect dependent on the at least one measurement variable;
a first sensor arrangement configured to generate a first sensor signal having a first frequency spectrum influenced by the fluid flowing within the first portion;
a second sensor arrangement configured to generate a second sensor signal having a second frequency spectrum influenced by the fluid flowing within the third portion, the second frequency spectrum deviating from the first frequency spectrum and/or including at least one wanted component, the at least one wanted component including a spectral signal component influenced by the at least one measurement variable as regards at least one signal parameter; and
a transmitter electronics including a microprocessor and configured to:
receive the first sensor signal and convert such into a first sensor signal sampling sequence approximating the first sensor signal, the first sensor signal sampling sequence including a first sequence of digital sampled values, defined by SD1[m]=SD1[tm·fs1], using a first sampling rate, defined by fs1=1/(tm+1-tm)=1/Ts1, from the first sensor signal at different sampling points in time, given by tn=n·Ts1;
receive the second sensor signal and convert such into a second sensor signal sampling sequence approximating the second sensor signal, the second sensor signal sampling sequence including a second sequence of digital sampled values, defined by SD2[n]=SD2[tn·fs2] using a second sampling rate, defined by fs2=1/(tn+1-tn)=1/Ts2, from the second sensor signal at different sampling points in time, given by tn=n·Ts2, such that the second sensor signal sampling sequence approximates at least one wanted spectral signal component of the second sensor signal influenced by the at least one measurement variable;
using a digital adaptive filter, ascertain from the first sensor signal sampling sequence a wanted signal filter coefficients set including a set of N filter coefficients;
using the wanted signal filter coefficients set, generate a first z-transfer function of a wanted signal filter, defined as:, G
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wherein wk are the filter coefficients, the wanted signal filter being a digital filter adapted to filter the second sensor signal sampling sequence such that the first z-transfer function of the wanted signal filter is determined by the wanted signal filter coefficients set;
generate a wanted signal sequence, using the wanted signal filter and the second sensor signal sampling sequence, the wanted signal sequence being a sequence of digital function values defined by:, S
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to generate from the wanted signal sequence a measured values sequence, being a sequence of digital measured values representing the at least one measurement variable and following one after the other in time.