xatax1
Newbie level 2
I want to design a digital butterworth lowpass filter of nth order, with only freedom of choice to user being order of the filter and the cut off frequency, i already have a 1st order low pass.
This is a very basic lowpass PT1 filter, i take the state space matrix, descrtize it and apply it to my signal. now i want to extend my library to butterworth. I am trying to use as many minimal matlab commands as possible. So i thought it's better to derive in hand before implementing it. i wanted to know how to deal with damping ratio as the order is progressed.
When i was searching for answer, i came across wiki of butter worth filter:
I can just hard code this, but have they considered damping ratio and how do i covert this to state space.
Any help would be greatfull
Code:
T = 1/(2*pi*this.fc);
this.A = -1/T;
this.B = 1/T;
this.C = 1;
this.D = 0;
This is a very basic lowpass PT1 filter, i take the state space matrix, descrtize it and apply it to my signal. now i want to extend my library to butterworth. I am trying to use as many minimal matlab commands as possible. So i thought it's better to derive in hand before implementing it. i wanted to know how to deal with damping ratio as the order is progressed.
When i was searching for answer, i came across wiki of butter worth filter:
I can just hard code this, but have they considered damping ratio and how do i covert this to state space.
Any help would be greatfull