Bilinear Transform and Butterworth Filters

Hi everyone,
I’ve been spending the latest days implementing a Butterwoth filter that relies on yours Filtering package.
What I had to implement is:

  • Bilinear Transform (should work with every filter, and probably with every LTI system)
  • Butterwoth Designer -> Given a set of input parameters (namely passband corner frequency, stopband corner frequency, passband ripple and stopband attenuation) it returns the minimum required filter order and the cutofff frequency
  • Butterworth coefficients calculator -> Given the order and the cutoff frequency returns a list of IIR coefficients to be used in your online filter.

Since it is a new request, I’d like to discuss with you if these new features they can be by any means useful or not.

Thank you


That would fit perfectly into what I originally had in mind with the Filtering package. Such a contribution would be very welcome, and certainly be useful!