butterworth coefficients

[kyra]

how to calculate the butterworth coefficients for IIR filter? and what is the equation to calculate  the coefficients from the butterworth coefficients .vi?

[Barp]

kyra,

Some people don't realize that, but we have a whole "book" in analysis and signal processing that ships with LabVIEW.

Depending of the version of LabVIEW, it is in PDF format or is included in Help.

In PDF, it is available in ...\National Instruments\LabVIEW <version>\manuals and it is called "analcon.pdf". There you can navegate to chapter 3 - Digital Filtering and look into IIR Filters.

In Help format, you can access opening the LabVIEW help and going to Concepts>>Fundamentals>>Signal Processing and Analysis>>Digital Filtering.

Notice that there, you have IIR Filters that answer some of your questions (at least how the equations) and it has an example on how to use.

Hope this helps!

[kyra]

thanks, but i'm looking the butterworth coefficients.vi function. and how the operation in the library function (Ivanlys.dll). and i want to know the algorithm for calculating the coefficients. the analcon.pdf and the LabVIEW help are not giving the specific details. sorry for my english.