I have a transfer function coefficients as following:
[b,a] = ellip(4,.2,40,[.41 .47]);
I'd like to factor this system into its PFE using
[r,p,k] = residue(b,a). Then, I'd like to implement a filter which uses a parallel combination of second-order subsections. To do this, I need to combine each complex pole with its complex conjugate so that the overall second order subsections will have real valued coefficients. Hence; I selected four pairs of first order terms and recombined them into second order subsections using "residue" function. How can I store the coefficients of the resulting second-order subsections in the matrices c and d so that each row corresponds to one second order system?
I tried to do this but I don't know whether it's correct or not?
[c1 d1]=residue([r(1) r(2)],[p(1) p(2)],0); [c2 d2]=residue([r(3) r(4)],[p(3) p(4)],0); [c3 d3]=residue([r(5) r(6)],[p(5) p(6)],0); [c4 d4]=residue([r(7) r(8)],[p(7) p(8)],k); [c d]=[c1 c2 c3 c4 d1 d2 d3 d4]
Can anybody please give me an idea? Any help would be appreciated