berndporr / iir1

Dear Dr. Porr,

I have checked the custom class but havn't quite understand it, is it possible for it to realize the following three filters with it?

Thank you very much.
Sincerely,
Qingwei Liu, AIST, Japan

Dear Dr. Porr,

My understanding is I can realize H2 with TwoPole,

iir1/iir/Custom.h

Line 76 in dd0124b

{

,
what I am confused is about H3, and also SOSCascade for H1.

Thank you very much.
Sincerely,
Qingwei Liu, AIST, Japan

These are all analogue filters in Laplace space. You need to transform that to z-space with the matched z transform or bilinar transform. Then factor them out as a chain of 2nd order digital filters (SOS). Then use the CustomSOS function to set the coefficients. I'd recommend you learn first how to translate an analogue filter into a digital one and do it with pen/paper or you can also use python functions to achieve that which can also generate the 2nd order chain. My teaching videos are here: https://www.youtube.com/user/DSPcourse/playlists?view=50&sort=dd&shelf_id=27

custom filter