CNiIIRCascadeFilter parameters?

[Heuristics]

Hello,

we want to use the class CNiIIRCascadeFilter.
Question: when we add low cutoff Bessel filter (ie Bessel(double fs, double fl, double fh)), which is the correct cutoff parameter, fs or fl. if it is fs, what given in fl: same as fs or 0.

Thanks for your answer,
Alain

[Jason F.]

Here is the explanation of CNiIIRCascadeFilter::Bessel as quoted from the Measurement Studio Reference:

CNiIIRCascadeFilter::Bessel()

Public Function Declared in: NiMath.h

Declaration
MathError Bessel(double fs, double fl, double fh);

Description:

Generates the set of cascade filter coefficients to implement the IIR filter as specified by the Bessel filter model.


Parameters

double fs - The sampling frequency in Hertz.

double fl - Lower cutoff frequency in Hertz.

double fh - Upper cutoff frequency in Hertz.

With this information you can see that the lower cutoff frequency is fl.

Jason F.
Applications Engineer
National Instruments
www.ni.com/ask