parfiltr.m

Digital signal processing using Matlab一書之範例程式

function y = parfiltr(C,B,A,x);
% PARALLEL form realization of IIR filters
% ----------------------------------------
%  [y] = parfiltr(C,B,A,x);
%  y = output sequence
%  C = polynomial (FIR) part when M >= N
%  B = K by 2 matrix of real coefficients containing bk's
%  A = K by 3 matrix of real coefficients containing ak's
%  x = input sequence
%
[K,L] = size(B);
N = length(x);
w = zeros(K+1,N);
w(1,:) = filter(C,1,x);
for i = 1:1:K
        w(i+1,:) = filter(B(i,:),A(i,:),x);
end
y = sum(w);